Where is Pentax and what's next?

jeffkrol · 09-11-2007, 08:00 AM

Originally posted by RiceHigh

Any direct link to be provided?

The vacation is a nice one except I was busy enough to visit so many people and places. Hawaii is a good and beautiful place and everywhere are clean. It's so relaxing. People are nice too.

Well, for the first time, I haven't brought any Pentax gear. And as such, there was nothing to be rambled about :-)

Btw, in the below link are two of the pictures taken from my Hawaii trip. Just look at the two pictures and forget about my article, so as to keep everything good! ;-D LOL..

RiceHigh's Pentax Blog: Underexposure Tendency of K10D and K100D

Deflect and change subject.....Quite a pattern.
ALSO, all you have to do is take your 5d and k100 and take 1 set of photos, 5d w/ FAKE iso and at 0 EV. K10 at REAL iso value and +1/2 EV..............

Last edited by jeffkrol; 09-11-2007 at 08:17 AM.

Maxington · 09-11-2007, 03:46 PM

Originally posted by codiac2600

The 40D is more professional than the 5D IMO because the focus is accurate and much faster than the 5D, weather sealed (like K10D from a year ago),

Just like to say, the 40D isn't weathersealed like the K10D, its just got a bit of sealing around card and battery if I recall, nothing around the buttons and so on. Its nowhere near weather resistant.

vinzer · 09-11-2007, 05:02 PM

Thanks for the laughs RH. You really can't hold a proper debate even if your life depended on it. You could probably make a good scam online dealer, since you're very much into bait and switch tactics. You start off comparing Pentax with the other camera brands (including your beloved Canon), and then a few posts ago you tell jeffkrol to forget about Canon first? Well, sorry, most of us here already are savvy with your posts.

It's a great honor that the K10D's still being mentioned alongside the next generation of DSLRs. Don't gripe that the K10D did a clean sweep of the major camera awards, honors given by people who really *know* what a good camera is (unlike you who's easily swayed by what's popular in the market). With Canon upgrading bodies every year, your camp is bound to win one, eventually. Then again, it's looking like Nikon would win sooner, so why not upgrade your P&S to a D3?

Baffle · 09-12-2007, 01:12 AM

Im sick of seeing this bloke put Pentax down, he must be getting paid to do it!
Have a look at his Quality shots taken
RiceHigh/Eastern Australia - Photobucket - Video and Image Hosting
They might improve now he has a p&s 5d

B051LjKo · 09-12-2007, 03:18 AM

Originally posted by Baffle

RiceHigh/Eastern Australia - Photobucket - Video and Image Hosting
They might improve now he has a p&s 5d

Nice pictures there RH, now I can totally understand why Pentax gear disappoints you. Its performance is just to crappy and it is definitly limiting your skill&performance...

RiceHigh · 09-12-2007, 08:28 AM

Originally posted by jeffkrol

Deflect and change subject.....Quite a pattern.
ALSO, all you have to do is take your 5d and k100 and take 1 set of photos, 5d w/ FAKE iso and at 0 EV. K10 at REAL iso value and +1/2 EV..............

Did the Pentax user manuals tell us that we need to apply a +1/2EV exposure compensation all the time in order to get properly exposed pictures???

Re-read the ANSI formula, know about the formula, then knowing what is the K factor. Note that the K factor is not a universal constant and can be changed by the camera manufacturer for its value as desired!

I know that you are still unwilling to read (since years ago when I told you to do so at DPR, even after I repeatedly provided you the formula). I know you read Doug Kerr's articles and got some of his viewpoints. But you seems to be yet unable to read and understand the ANSI formula up till now, which is again existent in his articles. Sad, really..

Well, whilst it is believed and told that the K factor used by Canon is at a value of 12.5, what is the value used by Pentax (as generally told by certain people who know it)? Do you know??

vinzer · 09-12-2007, 03:34 PM

Originally posted by RiceHigh

Did the Pentax user manuals tell us that we need to apply a +1/2EV exposure compensation all the time in order to get properly exposed pictures???

My manual certainly didn't, because I also don't need to. You make a gross assumption that the only properly exposed pictures that are acceptable are the ones that YOU think are properly exposed.

Don't be so pompous. The world doesn't revolve around you alone. I doubt you've even gone into the photos section of this forum where you can see perfectly-exposed photos without any EV applied.

There is no perfect formula for proper exposure. It's all subjective. You don't like Pentax's default metering? Fine, but don't dictate to us that we *all* need your proposed +1/2 EV adjustment.

Besides, that's why there's an EV compensation (if you wanna get technical, which is what you think you are, the exposure in "EV exposure compensation" is already redundant) - because not all people have the same ideas about proper exposure.

Seriously, go back to a point-and-shoot where everything is taken care of for you. The 5D is still too much camera for what you want, and for what you can handle.

jeffkrol · 09-12-2007, 04:10 PM

Originally posted by RiceHigh

Did the Pentax user manuals tell us that we need to apply a +1/2EV exposure compensation all the time in order to get properly exposed pictures???

Re-read the ANSI formula, know about the formula, then knowing what is the K factor. Note that the K factor is not a universal constant and can be changed by the camera manufacturer for its value as desired!

I know that you are still unwilling to read (since years ago when I told you to do so at DPR, even after I repeatedly provided you the formula). I know you read Doug Kerr's articles and got some of his viewpoints. But you seems to be yet unable to read and understand the ANSI formula up till now, which is again existent in his articles. Sad, really..

Well, whilst it is believed and told that the K factor used by Canon is at a value of 12.5, what is the value used by Pentax (as generally told by certain people who know it)? Do you know??

And you cannot read a simple statement by mr. Kerr:
3. The implication of this is that the camera in metered operation will provide an exposure on the sensor about 0.4 stop "hot" compared to what is contemplated by the ISO standards.
What more really needs to be said..........
Tell me in your own words what those words mean to you. To me this means Canon fudged the iso in order to make it easy for people like you. Simple. I realize, after years of being wrong in your assumption, you must defend your weak position (afterall to be wrong you would look quite foolish

), but come on, I'm giving you an opening to recant.......
BTW: The manual never tells you to expose the moon as if it was daylight. Nor to get a polar bear in a snowstorm pure white you need a +2 ev, ECT.
And Kodak apparently stopped puttting the "meter off this card and add 1/2ev to their greycard to get a proper exposure"... Read the back of some cards... You need counseling........
I've told you for years that, unlike Canon, Pentax just adhered stricter to the standard. If thats a problem for you fine. It's not a problem for me or a host of other people. AND there is a 1/2 stop fudge factor built in anyways. As you can see from the Kerr papers.
I never said one was "globally" better than the other (as you rant over and over and over and over and...) only if you understand the Pentax logic (the one you insist is "broke") you can deal with it. I mentioned before that a LOT of Canon "expert" shots have negative EV dialed in. Baronlindas EXCELLENT bird shots rarely had oEV and NONE that I remember had a plus EV. Almost all were negative EV. From that I could go around Yelling that Canon overexposes, but since I know their ISO is FAKED and eliminates the "headroom" for blowouts, I could deal with it and add EV values AS I DEEM fit..
Does the Canon manual tell you to underexpose birds???? EV is a tool to use when you understand what the meter does.
Your logic is going down hill fast...........And who really gives a rats as* what K factor Pentax uses, only thing you need to know is "is it consistent" and to deal with it.
AND my favorite quote:
'The exposure meter is calibrated to some clearly defined standards and the user needs to adjust his working method and his subject matter to these values. It does not help to suppose all kinds of assumptions that do not exist.'
Erwin Puts
Too bad I don't favor banning you, would end my amusement, but it would make you 3 out of 4 or so.....

And just for fun, I'll throw in Mr. Hogan's paper, which you so blithly dismiss, might as well throw Nikon in the mix:
So all you have to do is take your Pentax and Canon. Find a scene, metr off a grey card w/ both at +1/2 EV and see what it looks like oh Mr. measurebator........
Meters Don't See 18% Gray by Thom Hogan
1. Does Nikon calibrate its meters to ANSI standards? (My previous conversations with Nikon engineers leads me to believe the answer is yes.)
2. Would you need a 12% gray card to get the correct exposure using an ANSI calibrated meter (i.e., is the luminance setting for ANSI really equivalent to 12% reflectance?)? (I believe the answer is again yes, but we can make do with 18% gray cards. Simply take a reading with the card angled between the lens axis and light source, then open up 1/2 stop.)
You'll note that some recent Kodak gray cards have had a somewhat cryptic message on them about using compensation to get correct results. There have been several threads on photo.net discussing this issue without resolution:

photo.net Forum: Why does Kodak say to compensate their graycard?! photo.net Forum: grey card

But don't take the vacillation in photo.net posts to mean that that 12% isn't a fact. Former Shutterbug editor Bob Shell co-authored a book with Martin Silverman and Jim Zuckerman that goes into great detail about the issue (The Hand Exposure Meter Book).
...................
For example, Sekonic's web page mentions 14% and claims Minolta uses a higher setting, while Minolta's English pages claim yet a different value.)

ANSI standards (which, unfortunately, are not publically published--you have to pay big bucks to have access to them), calibrate meters using luminance, not reflection. For an ANSI calibrated meter, the most commonly published information I've seen is that the luminance value used translates into a reflectance of 12%. I've also seen 12.5% and 13% (so where the heck does Sekonic's 14% come from?), but 12% seems to be correct--one half stop lighter than 18%, by the way. I haven't seen anyone claim that ANSI calibration translates into a reflectance of 18%.

MORE stuff........
http://www.adobeforums.com/cgi-bin/webx?14@@.3bb5bcf7/37
You can check the calibration of your meter. If it is calibrated correctly for the equivalent of 12% reflectance, a reading from a Kodak 18% gray card exposed with +0.5 EV compensation should give a pixel value of 118 (118/110 what the difference but it is NOT 127) in sRGB. This is calculated from the sRGB equation, where pixel value = (1.055*reflectance^(1/2.4)-0.055)*255. For my own camera (Nikon D70) I get a value very close to this. As you go further from the midpoint, the tone curve applied by the camera or raw converter will increasingly depart from the calculated result.

If you want to place the highlight, it is best to perform a series of test shots with bracketing and use the ISO that gives the desired results.

And just a related link for fun:
Adobe Forums - Exposure to the right and tone placement
Oh to put a face on it, in your words............
Read the EV meter's reading. Then first dial in that particular EV into your DSLR in Manual mode. To set the Av and Tv, you should note that EV 1 is 1 second at f/1, EV 2 is 1/2 second at f/1 or 1 second at f/1.4 and so on, regardless of the ISO sensitivity setting. Assuming that your DSLR's sensor has been calibrated to comply the 18% standard and the exposure control of your DSLR is accurate, you should be able to get a peak somewhere close enough to the 128 at the centre in the camera's histogram, like this:-

4348.jpg Furthermore, you can see the dark and the bright "peaks" as well.
RiceHigh's (Pentax) DSLR and Lens Measurbation Page on Exposure Accuracy and More..
WRONG,WRONG, WRONG..............
and your 43 f1.9 WAS SPOT ON or maybe slightly overexposed.

And your Canon was .5 stop OVEREXPOSED..... Actually .7 over to be precise w/ pattern metering.....
Your FAJ sucked but almost all others were spot on in CW metering. Don't even bring up "matrix" metering, we've been down that road before.
About the only true anomoly is why is the spot meter so low.... THAT is not so much an issue (it is what it is) as a question. One I personally don't need answered but I darn well know what to do with it.
Take ALL your exposure data and add 1/2 stop and then talk to me............actually forget it.......

equinox · 09-12-2007, 04:55 PM

[QUOTE=RiceHigh;94658]Did the Pentax user manuals tell us that we need to apply a +1/2EV exposure compensation all the time in order to get properly exposed pictures???
QUOTE]

My Pentax does not require full time + 1/2EV, nor my Canon or my Olympus. Of course their are times you have to dial in EV either way to correct exposure on any camera. Photography course 101; I suggest you learn before posting such mistruths as you have no photography knowledge. A poor tradesman always blames their tools,and you consistantly blame something that is a defect of your own making.

May I suggest you take up finger painting to get proper exposure, although I bet you would either blame Pentax or screw this up too!

RiceHigh · 09-12-2007, 07:53 PM

Originally posted by jeffkrol

And you cannot read a simple statement by mr. Kerr:
3. The implication of this is that the camera in metered operation will provide an exposure on the sensor about 0.4 stop "hot" compared to what is contemplated by the ISO standards.

. . . SNIPPED . . .

What more really needs to be said..........Take ALL your exposure data and add 1/2 stop and then talk to me............actually forget it.......

I know what Kerr is talking about and I do understand what he talks (which is what you have kept referrring to) but I'm afraid his conclusion has been drawn up too fast. So, I've hinted you to back to the basic, which is the ANSI formula which Doug Kerr has written down for it in his essay.

So, let's review the two key points as presented by Doug Kerr:

1. Canon's ISO speed is actually 1/3 stop faster than the true ISO standard, as rated (well, Phil Askey has measured and said the same too);

2. Doug *believes* that the K factor used by Canon is 12.5 because he measured a value of 12.7 by measuring the Exposure Value and then calculate back the K factor by assuming the value of another "constant";

For those others who read here but haven't come across Doug Kerr's excellent articles, I provide the source links below:

http://doug.kerr.home.att.net/pumpkin/Exposure_Calibration.pdf

http://doug.kerr.home.att.net/pumpkin/Scene_Reflectance.pdf

Now, what Doug has *assumed* is that his 300D is exposing like film as it *should* be. However, I would think one-step more deeper. If Canon just wish to make a brighter exposure, what they just need to do is to adjust the K factor of their camera's reflective light meter. They need not to keep 12.5 and also need not to raise the actual ISO sensitivity (which requires tweaking to the hardware amplifier for the CMOS sensor). So, the complicated action done is highly questionable.

And, in the old film days, Minolta and Pentax used a K factor of 14 (I verify this in the Minolta pro light meter's user manual - link contained in my homepage but now deleted by the KM already, but I shall provide my direct homepage link for the relevant paragraph below) and Canon and Nikon uses a value of 12.5. A value of 14 means the exposure results will be brighter as the EV and the K are put in inverse positions in the ANSI formula.

So, my (maybe wild) guess to this somehow strange phenomenon and design arrangement is that Canon intentionally overexpose the image by +1/3 stop (expose to the right) and then compress the image by underexpose by -1/3 by the DIGIC processor. By doing so, it will always improve S/N ratio of the image and thus less visible noise.

So, people will then ask then this would result in highlight overblown? Remember there is a +1/2 headroom for th highlight already with a K factor of 12.5 (which is again smaller than the maximum value ANSI recommended, i.e., 13.6)? So, there is still a 1/6EV "cushion" left. My this proposition explains also why Canon DSLRs are more vulnerable for highlight blowing, just because the cushion has now been set smaller, i.e., from 1/2EV to 1/6EV. But still there is a *margin* here. As long as the Canon metering and exposure system is highly accurate (my experience is), this "risky" design can work.

As for Thom's article, he did in fact over-simplify the case and I had addressed about Thom's article long ago with reference to the ANSI's formula. Despite that you had kept refusing to read my this simple paragraph, I will post the link for others' reading and digestion:

RiceHigh's (Pentax) DSLR and Lens Measurbation Page on Exposure Accuracy and More..

So, the basic is all about the ANSI formula, which we should read about.

Besides, regarding where the mid-grey is: 110 or 118 (both you have told us) or 128 are not really that important. If you believe my determination of 128 as mid-grey and proper exposure is incorrect, then everyone can read my test results with a 110 lower value in mind as correct to see if the Pentax DSLR system's exposure is consistent or accurate, or not:-

RiceHigh's (Pentax) DSLR and Lens Measurbation Page on Exposure Accuracy and More..

Finally, I still wish to remind you that K factor is not equal to reflectance! K=12.5% does NOT imply a light meter calibrated for a scene reflectance of 12.5% - PLS DO re-read the ANSI formula.

P.S. I really don't understand why you still cannot discuss on the topic in accordance to the ANSI formula but first reading and understood it before went and go further into the discussion - for so many years!

P.S. 2: Doug, Thom, RiceHigh and Anyone can be wrong in assuming anything inside the DSLR black boxes are doing. But, the ANSI formula cannot be wrong!

jeffkrol · 09-12-2007, 09:49 PM

Originally posted by RiceHigh

I know what Kerr is talking about and I do understand what he talks (which is what you have kept referrring to) but I'm afraid his conclusion has been drawn up too fast. So, I've hinted you to back to the basic, which is the ANSI formula which Doug Kerr has written down for it in his essay.

So, let's review the two key points as presented by Doug Kerr:

1. Canon's ISO speed is actually 1/3 stop faster than the true ISO standard, as rated (well, Phil Askey has measured and said the same too);

2. Doug *believes* that the K factor used by Canon is 12.5 because he measured a value of 12.7 by measuring the Exposure Value and then calculate back the K factor by assuming the value of another "constant";

For those others who read here but haven't come across Doug Kerr's excellent articles, I provide the source links below:

http://doug.kerr.home.att.net/pumpkin/Exposure_Calibration.pdf

http://doug.kerr.home.att.net/pumpkin/Scene_Reflectance.pdf

Now, what Doug has *assumed* is that his 300D is exposing like film as it *should* be. However, I would think one-step more deeper. If Canon just wish to make a brighter exposure, what they just need to do is to adjust the K factor of their camera's reflective light meter.

And their meter would no longer match anyone elses. That has already been eluded to.
6. They could have done this by adopting a hotter "calibration" of the exposure metering system than called for by the ISO stadanrd. But if they did, then a photographer who used an external exposure meter (calibrated in accordance with the ISO standard) would get a different exposure recomendation than for the metering system in the camera. This would have caused a lot of consternation.

Originally posted by RiceHigh

They need not to keep 12.5 and also need not to raise the actual ISO sensitivity (which requires tweaking to the hardware amplifier for the CMOS sensor). So, the complicated action done is highly questionable.
And, in the old film days, Minolta and Pentax used a K factor of 14 (I verify this in the Minolta pro light meter's user manual - link contained in my homepage but now deleted by the KM already, but I shall provide my direct homepage link for the relevant paragraph below) and Canon and Nikon uses a value of 12.5. A value of 14 means the exposure results will be brighter as the EV and the K are put in inverse positions in the ANSI formula.
So, my (maybe wild) guess to this somehow strange phenomenon and design arrangement is that Canon intentionally overexpose the image by +1/3 stop (expose to the right) and then compress the image by underexpose by -1/3 by the DIGIC processor. By doing so, it will always improve S/N ratio of the image and thus less visible noise.

Guesses are just guesses and worthless in this discussion. Where do you get the idea that they de-expose the image w/ the DIGIC??? THAT my friend is the goofiest thing I ever heard from you. The images are overexposed in A METER SENSE, period. NO "correction" in the DIGIC.....fantasy and wishful thinking is all I'm reading here.

Originally posted by RiceHigh

So, people will then ask then this would result in highlight overblown? Remember there is a +1/2 headroom for th highlight already with a K factor of 12.5 (which is again smaller than the maximum value ANSI recommended, i.e., 13.6)? So, there is still a 1/6EV "cushion" left. My this proposition explains also why Canon DSLRs are more vulnerable for highlight blowing, just because the cushion has now been set smaller, i.e., from 1/2EV to 1/6EV. But still there is a *margin* here. As long as the Canon metering and exposure system is highly accurate (my experience is), this "risky" design can work.
As for Thom's article, he did in fact over-simplify the case and I had addressed about Thom's article long ago with reference to the ANSI's formula. Despite that you had kept refusing to read my this simple paragraph, I will post the link for others' reading and digestion:

RiceHigh's (Pentax) DSLR and Lens Measurbation Page on Exposure Accuracy and More..

So, the basic is all about the ANSI formula, which we should read about.

Originally posted by RiceHigh

Besides, regarding where the mid-grey is: 110 or 118 (both you have told us) or 128 are not really that important. If you believe my determination of 128 as mid-grey and proper exposure is incorrect, then everyone can read my test results with a 110 lower value in mind as correct to see if the Pentax DSLR system's exposure is consistent or accurate, or not:-

EXCUSE ME, Just correct your own erronious data. You based a lot of broad conclusions based on your mistaken belief in 126. You incessently argued the fact for YEARS. Now you change your statements? Nothing worse than erroneous facts and FUD.

Originally posted by RiceHigh

Finally, I still wish to remind you that K factor is not equal to reflectance! K=12.5% does NOT imply a light meter calibrated for a scene reflectance of 12.5% - PLS DO re-read the ANSI formula.

Already been addressed...... "luminance value used translates into a reflectance of 12%." Translates to... not equal. Every reference already either states this or eludes to it...

Originally posted by RiceHigh

P.S. I really don't understand why you still cannot discuss on the topic in accordance to the ANSI formula but first reading and understood it before went and go further into the discussion - for so many years!

Same reason you refuse to admit that a calibrated meter should not peak at 126.....

Originally posted by RiceHigh

P.S. 2: Doug, Thom, RiceHigh and Anyone can be wrong in assuming anything inside the DSLR black boxes are doing. But, the ANSI formula cannot be wrong!

But you sure can be......
Might as well throw Bob Shell et. al., Julia Borg, AND Michael Reichman
("The classic examples of how reflective meters can be lead astray are the examples of a black cat in a coal mine or a white cat in a snow storm. In both cases if you were to trustingly use even the most sophisticated multi-zone matrix metering system you would end up with very badly underexposed and overexposed negatives or transparencies. The reason, of course, is that the meter sees the black cat and coal, or the white cat and snow as being 13% gray. Even the smartest computer algorithms can't (yet) understand what the subject is, and since there is nothing else in the scene they will provide "correct" but inappropriate exposures.)
Understanding-Exposure
in the mix as well. Didn't realize you were Ricey-coyote super genious....
Her's your "bible". Why don't you walk me through your calculations......
step by step.........
http://www.largeformatphotography.info/articles/conrad-meter-cal.pdf

RiceHigh · 09-12-2007, 11:24 PM

Mr. 110,

Have you read the ANSI formula yet then?

Whilst you keep emphasizing the faster ISO speed of Canon DSLRs is a problem, do you think a faster actual ISO of Canon DSLRs will cure the inaccuracy exposure problem of Pentax DSLRs?

They are two totally irrelevant cases afterall. Also, how many of the typical DSLR users will use an external meter to meter instead of using the internal meter? If I could use an external meter, actually the exposure problem of the Pentax DSLRs had been resolved long ago - that what I said in my homepage, as I did mention that the ISO speed of my Pentax DSLRs are accurate, as tested. As for Canon's case, it is not very difficult to tackle even if one use an external meter, just dial in 1/3EV less in the camera or 1/3EV more at the light meter for the ISO rating then case closed, e.g., ISO 160 in camera and ISO 200 at handheld meter.

As for 110, 118 and 126, 127 or 128 as mid-tone, different people say different values. Doug Kerr writes 118 in one of his articles. A search on the net returns quite some results of 128. You insist 110 and 126 for me (which I have never said 126). Remember the "hearsay" theory of yours? Which one should be correct?

And, could you explain to me why 110 should be the mid-grey value?? And why Doug Kerr says 118? You keep saying that 110 = sRGB is meaningless actually. What we need to know is why is that! Any supporting documents which can give us a technical reason for that? (don't give us more "hearsay" links!)

Anyway, a histogram at 0 is total dark and 255 is total white. In the middle of white and dark is the mid-tone and that the histogram is linear as percepted by human eyes. What's wrong with 128 as mid-tone? Pls explain.

Bottom line: most people says 128 - do a web search and you can see all those photo and technical pages and forum posts. But then the majority could still be wrong anyway. And, YOU may be the ONLY ONE who is correct, hopefully.

But since you insist 110, I just try to suggest you (and anyone as well) to try to intrepret my test results in another way. My Pentax DSLRs exposed for the mid-grey (where I metered on) for results that returned the values from 70 something to 130 something, with different lenses and/or different metering modes. And as for the Spot metering, it is often under (less than or far less than 110) But with the Canon DSLR, the results are always close to 128 and well within the 1/3 EV margin.

So, if you like darker pictures which are reverted to 110 for your own preference (as you say) that's fine. However, you still cannot get around the 110 most of the time but something varied from time to time. In my book, this is simply called "inconsistency" and actually inaccuracy.

Yours,
Mr. 128

Chako · 09-13-2007, 04:03 AM

I dare say I know more about photography then you do RH. I teach it after all. I will not get into this measurebating debate that seems so pointless and infantile. I will say however, that you should go out and take more photos. From the few photos I have seen posted above, you could use a few pointers on good composition, eye paths, tonality, and the use of the rule of thirds. Only once you have learned the basics, can you break them to good effects.

Oh and as a Canon user, I have come across a few posts of him complaining about the 5D on other forums. So folks, we have a person who will never be truly satisfied with his/her gear because the equipment must be at fault. It is easier to blame the equipment then to blame a person’s lack of photographic skills.

This is not meant as an insult, although I am sure you must thrive on them by now. Consider it more an honest opinion based upon the few threads I have encountered here and on other forums that I may lurk of a photographic nature.

RiceHigh · 09-13-2007, 04:24 AM

Originally posted by Chako

I dare say I know more about photography then you do RH. I teach it after all. I will not get into this measurebating debate that seems so pointless and infantile. I will say however, that you should go out and take more photos. From the few photos I have seen posted above, you could use a few pointers on good composition, eye paths, tonality, and the use of the rule of thirds. Only once you have learned the basics, can you break them to good effects.

Oh and as a Canon user, I have come across a few posts of him complaining about the 5D on other forums. So folks, we have a person who will never be truly satisfied with his/her gear because the equipment must be at fault. It is easier to blame the equipment then to blame a person’s lack of photographic skills.

This is not meant as an insult, although I am sure you must thrive on them by now. Consider it more an honest opinion based upon the few threads I have encountered here and on other forums that I may lurk of a photographic nature.

This is surely not insult but just a matter of fact.

However, your reply post is totally irrelevant and is actually off-topic. When we are all here at a *gear forum* in talking about our gear, say, features, specs, pros and cons, field performance and accuracy etc. then you just jump out to reply: "your photos are sucking, pls shut up." Then this is a totally irrelevant and off-topic post. Of course, it is useless.

What you are talking about is just what Ken Rockwell had told us long ago: measurbators don't take photos and they wasted all their time in measurbating; and; even they attempt, their photos suck. What's actually new here? Nothing.

RiceHigh · 09-13-2007, 04:31 AM

Originally posted by Chako

I dare say I know more about photography then you do RH. I teach it after all.

And, please show us your excellent photos, our teacher.

09-12-2007, 08:28 AM	#96
RiceHigh Veteran Member Join Date: Nov 2006 Location: Hong Kong Posts: 1,934 Original Poster	When you quote ANSI standard, you should read the formula! Originally posted by jeffkrol Deflect and change subject.....Quite a pattern. ALSO, all you have to do is take your 5d and k100 and take 1 set of photos, 5d w/ FAKE iso and at 0 EV. K10 at REAL iso value and +1/2 EV.............. Did the Pentax user manuals tell us that we need to apply a +1/2EV exposure compensation all the time in order to get properly exposed pictures??? Re-read the ANSI formula, know about the formula, then knowing what is the K factor. Note that the K factor is not a universal constant and can be changed by the camera manufacturer for its value as desired! I know that you are still unwilling to read (since years ago when I told you to do so at DPR, even after I repeatedly provided you the formula). I know you read Doug Kerr's articles and got some of his viewpoints. But you seems to be yet unable to read and understand the ANSI formula up till now, which is again existent in his articles. Sad, really.. Well, whilst it is believed and told that the K factor used by Canon is at a value of 12.5, what is the value used by Pentax (as generally told by certain people who know it)? Do you know??

09-12-2007, 04:10 PM	#98
jeffkrol Veteran Member Join Date: Sep 2006 Location: Wisconsin USA Photos: Gallery Posts: 8,434	Originally posted by RiceHigh Did the Pentax user manuals tell us that we need to apply a +1/2EV exposure compensation all the time in order to get properly exposed pictures??? Re-read the ANSI formula, know about the formula, then knowing what is the K factor. Note that the K factor is not a universal constant and can be changed by the camera manufacturer for its value as desired! I know that you are still unwilling to read (since years ago when I told you to do so at DPR, even after I repeatedly provided you the formula). I know you read Doug Kerr's articles and got some of his viewpoints. But you seems to be yet unable to read and understand the ANSI formula up till now, which is again existent in his articles. Sad, really.. Well, whilst it is believed and told that the K factor used by Canon is at a value of 12.5, what is the value used by Pentax (as generally told by certain people who know it)? Do you know?? And you cannot read a simple statement by mr. Kerr: 3. The implication of this is that the camera in metered operation will provide an exposure on the sensor about 0.4 stop "hot" compared to what is contemplated by the ISO standards. What more really needs to be said.......... Tell me in your own words what those words mean to you. To me this means Canon fudged the iso in order to make it easy for people like you. Simple. I realize, after years of being wrong in your assumption, you must defend your weak position (afterall to be wrong you would look quite foolish ), but come on, I'm giving you an opening to recant....... BTW: The manual never tells you to expose the moon as if it was daylight. Nor to get a polar bear in a snowstorm pure white you need a +2 ev, ECT. And Kodak apparently stopped puttting the "meter off this card and add 1/2ev to their greycard to get a proper exposure"... Read the back of some cards... You need counseling........ I've told you for years that, unlike Canon, Pentax just adhered stricter to the standard. If thats a problem for you fine. It's not a problem for me or a host of other people. AND there is a 1/2 stop fudge factor built in anyways. As you can see from the Kerr papers. I never said one was "globally" better than the other (as you rant over and over and over and over and...) only if you understand the Pentax logic (the one you insist is "broke") you can deal with it. I mentioned before that a LOT of Canon "expert" shots have negative EV dialed in. Baronlindas EXCELLENT bird shots rarely had oEV and NONE that I remember had a plus EV. Almost all were negative EV. From that I could go around Yelling that Canon overexposes, but since I know their ISO is FAKED and eliminates the "headroom" for blowouts, I could deal with it and add EV values AS I DEEM fit.. Does the Canon manual tell you to underexpose birds???? EV is a tool to use when you understand what the meter does. Your logic is going down hill fast...........And who really gives a rats as* what K factor Pentax uses, only thing you need to know is "is it consistent" and to deal with it. AND my favorite quote: 'The exposure meter is calibrated to some clearly defined standards and the user needs to adjust his working method and his subject matter to these values. It does not help to suppose all kinds of assumptions that do not exist.' Erwin Puts Too bad I don't favor banning you, would end my amusement, but it would make you 3 out of 4 or so..... And just for fun, I'll throw in Mr. Hogan's paper, which you so blithly dismiss, might as well throw Nikon in the mix: So all you have to do is take your Pentax and Canon. Find a scene, metr off a grey card w/ both at +1/2 EV and see what it looks like oh Mr. measurebator........ Meters Don't See 18% Gray by Thom Hogan 1. Does Nikon calibrate its meters to ANSI standards? (My previous conversations with Nikon engineers leads me to believe the answer is yes.) 2. Would you need a 12% gray card to get the correct exposure using an ANSI calibrated meter (i.e., is the luminance setting for ANSI really equivalent to 12% reflectance?)? (I believe the answer is again yes, but we can make do with 18% gray cards. Simply take a reading with the card angled between the lens axis and light source, then open up 1/2 stop.) You'll note that some recent Kodak gray cards have had a somewhat cryptic message on them about using compensation to get correct results. There have been several threads on photo.net discussing this issue without resolution: photo.net Forum: Why does Kodak say to compensate their graycard?! photo.net Forum: grey card But don't take the vacillation in photo.net posts to mean that that 12% isn't a fact. Former Shutterbug editor Bob Shell co-authored a book with Martin Silverman and Jim Zuckerman that goes into great detail about the issue (The Hand Exposure Meter Book). ................... For example, Sekonic's web page mentions 14% and claims Minolta uses a higher setting, while Minolta's English pages claim yet a different value.) ANSI standards (which, unfortunately, are not publically published--you have to pay big bucks to have access to them), calibrate meters using luminance, not reflection. For an ANSI calibrated meter, the most commonly published information I've seen is that the luminance value used translates into a reflectance of 12%. I've also seen 12.5% and 13% (so where the heck does Sekonic's 14% come from?), but 12% seems to be correct--one half stop lighter than 18%, by the way. I haven't seen anyone claim that ANSI calibration translates into a reflectance of 18%. MORE stuff........ http://www.adobeforums.com/cgi-bin/webx?14@@.3bb5bcf7/37 You can check the calibration of your meter. If it is calibrated correctly for the equivalent of 12% reflectance, a reading from a Kodak 18% gray card exposed with +0.5 EV compensation should give a pixel value of 118 (118/110 what the difference but it is NOT 127) in sRGB. This is calculated from the sRGB equation, where pixel value = (1.055reflectance^(1/2.4)-0.055)255. For my own camera (Nikon D70) I get a value very close to this. As you go further from the midpoint, the tone curve applied by the camera or raw converter will increasingly depart from the calculated result. If you want to place the highlight, it is best to perform a series of test shots with bracketing and use the ISO that gives the desired results. And just a related link for fun: Adobe Forums - Exposure to the right and tone placement Oh to put a face on it, in your words............ Read the EV meter's reading. Then first dial in that particular EV into your DSLR in Manual mode. To set the Av and Tv, you should note that EV 1 is 1 second at f/1, EV 2 is 1/2 second at f/1 or 1 second at f/1.4 and so on, regardless of the ISO sensitivity setting. Assuming that your DSLR's sensor has been calibrated to comply the 18% standard and the exposure control of your DSLR is accurate, you should be able to get a peak somewhere close enough to the 128 at the centre in the camera's histogram, like this:- 4348.jpg Furthermore, you can see the dark and the bright "peaks" as well. RiceHigh's (Pentax) DSLR and Lens Measurbation Page on Exposure Accuracy and More.. WRONG,WRONG, WRONG.............. and your 43 f1.9 WAS SPOT ON or maybe slightly overexposed. And your Canon was .5 stop OVEREXPOSED..... Actually .7 over to be precise w/ pattern metering..... Your FAJ sucked but almost all others were spot on in CW metering. Don't even bring up "matrix" metering, we've been down that road before. About the only true anomoly is why is the spot meter so low.... THAT is not so much an issue (it is what it is) as a question. One I personally don't need answered but I darn well know what to do with it. Take ALL your exposure data and add 1/2 stop and then talk to me............actually forget it....... Last edited by jeffkrol; 09-12-2007 at 06:25 PM.

09-12-2007, 09:49 PM	#101
jeffkrol Veteran Member Join Date: Sep 2006 Location: Wisconsin USA Photos: Gallery Posts: 8,434	Originally posted by RiceHigh I know what Kerr is talking about and I do understand what he talks (which is what you have kept referrring to) but I'm afraid his conclusion has been drawn up too fast. So, I've hinted you to back to the basic, which is the ANSI formula which Doug Kerr has written down for it in his essay. So, let's review the two key points as presented by Doug Kerr: 1. Canon's ISO speed is actually 1/3 stop faster than the true ISO standard, as rated (well, Phil Askey has measured and said the same too); 2. Doug believes that the K factor used by Canon is 12.5 because he measured a value of 12.7 by measuring the Exposure Value and then calculate back the K factor by assuming the value of another "constant"; For those others who read here but haven't come across Doug Kerr's excellent articles, I provide the source links below: http://doug.kerr.home.att.net/pumpkin/Exposure_Calibration.pdf http://doug.kerr.home.att.net/pumpkin/Scene_Reflectance.pdf Now, what Doug has assumed is that his 300D is exposing like film as it should be. However, I would think one-step more deeper. If Canon just wish to make a brighter exposure, what they just need to do is to adjust the K factor of their camera's reflective light meter. And their meter would no longer match anyone elses. That has already been eluded to. 6. They could have done this by adopting a hotter "calibration" of the exposure metering system than called for by the ISO stadanrd. But if they did, then a photographer who used an external exposure meter (calibrated in accordance with the ISO standard) would get a different exposure recomendation than for the metering system in the camera. This would have caused a lot of consternation. Originally posted by RiceHigh They need not to keep 12.5 and also need not to raise the actual ISO sensitivity (which requires tweaking to the hardware amplifier for the CMOS sensor). So, the complicated action done is highly questionable. And, in the old film days, Minolta and Pentax used a K factor of 14 (I verify this in the Minolta pro light meter's user manual - link contained in my homepage but now deleted by the KM already, but I shall provide my direct homepage link for the relevant paragraph below) and Canon and Nikon uses a value of 12.5. A value of 14 means the exposure results will be brighter as the EV and the K are put in inverse positions in the ANSI formula. So, my (maybe wild) guess to this somehow strange phenomenon and design arrangement is that Canon intentionally overexpose the image by +1/3 stop (expose to the right) and then compress the image by underexpose by -1/3 by the DIGIC processor. By doing so, it will always improve S/N ratio of the image and thus less visible noise. Guesses are just guesses and worthless in this discussion. Where do you get the idea that they de-expose the image w/ the DIGIC??? THAT my friend is the goofiest thing I ever heard from you. The images are overexposed in A METER SENSE, period. NO "correction" in the DIGIC.....fantasy and wishful thinking is all I'm reading here. Originally posted by RiceHigh So, people will then ask then this would result in highlight overblown? Remember there is a +1/2 headroom for th highlight already with a K factor of 12.5 (which is again smaller than the maximum value ANSI recommended, i.e., 13.6)? So, there is still a 1/6EV "cushion" left. My this proposition explains also why Canon DSLRs are more vulnerable for highlight blowing, just because the cushion has now been set smaller, i.e., from 1/2EV to 1/6EV. But still there is a margin here. As long as the Canon metering and exposure system is highly accurate (my experience is), this "risky" design can work. As for Thom's article, he did in fact over-simplify the case and I had addressed about Thom's article long ago with reference to the ANSI's formula. Despite that you had kept refusing to read my this simple paragraph, I will post the link for others' reading and digestion: RiceHigh's (Pentax) DSLR and Lens Measurbation Page on Exposure Accuracy and More.. So, the basic is all about the ANSI formula, which we should read about. Originally posted by RiceHigh Besides, regarding where the mid-grey is: 110 or 118 (both you have told us) or 128 are not really that important. If you believe my determination of 128 as mid-grey and proper exposure is incorrect, then everyone can read my test results with a 110 lower value in mind as correct to see if the Pentax DSLR system's exposure is consistent or accurate, or not:- EXCUSE ME, Just correct your own erronious data. You based a lot of broad conclusions based on your mistaken belief in 126. You incessently argued the fact for YEARS. Now you change your statements? Nothing worse than erroneous facts and FUD. Originally posted by RiceHigh Finally, I still wish to remind you that K factor is not equal to reflectance! K=12.5% does NOT imply a light meter calibrated for a scene reflectance of 12.5% - PLS DO re-read the ANSI formula. Already been addressed...... "luminance value used translates into a reflectance of 12%." Translates to... not equal. Every reference already either states this or eludes to it... Originally posted by RiceHigh P.S. I really don't understand why you still cannot discuss on the topic in accordance to the ANSI formula but first reading and understood it before went and go further into the discussion - for so many years! Same reason you refuse to admit that a calibrated meter should not peak at 126..... Originally posted by RiceHigh P.S. 2: Doug, Thom, RiceHigh and Anyone can be wrong in assuming anything inside the DSLR black boxes are doing. But, the ANSI formula cannot be wrong! But you sure can be...... Might as well throw Bob Shell et. al., Julia Borg, AND Michael Reichman ("The classic examples of how reflective meters can be lead astray are the examples of a black cat in a coal mine or a white cat in a snow storm. In both cases if you were to trustingly use even the most sophisticated multi-zone matrix metering system you would end up with very badly underexposed and overexposed negatives or transparencies. The reason, of course, is that the meter sees the black cat and coal, or the white cat and snow as being 13% gray. Even the smartest computer algorithms can't (yet) understand what the subject is, and since there is nothing else in the scene they will provide "correct" but inappropriate exposures.) Understanding-Exposure in the mix as well. Didn't realize you were Ricey-coyote super genious.... Her's your "bible". Why don't you walk me through your calculations...... step by step......... http://www.largeformatphotography.info/articles/conrad-meter-cal.pdf Last edited by jeffkrol; 09-12-2007 at 09:59 PM.

09-13-2007, 04:24 AM	#104
RiceHigh Veteran Member Join Date: Nov 2006 Location: Hong Kong Posts: 1,934 Original Poster	Useless.. Originally posted by Chako I dare say I know more about photography then you do RH. I teach it after all. I will not get into this measurebating debate that seems so pointless and infantile. I will say however, that you should go out and take more photos. From the few photos I have seen posted above, you could use a few pointers on good composition, eye paths, tonality, and the use of the rule of thirds. Only once you have learned the basics, can you break them to good effects. Oh and as a Canon user, I have come across a few posts of him complaining about the 5D on other forums. So folks, we have a person who will never be truly satisfied with his/her gear because the equipment must be at fault. It is easier to blame the equipment then to blame a person’s lack of photographic skills. This is not meant as an insult, although I am sure you must thrive on them by now. Consider it more an honest opinion based upon the few threads I have encountered here and on other forums that I may lurk of a photographic nature. This is surely not insult but just a matter of fact. However, your reply post is totally irrelevant and is actually off-topic. When we are all here at a gear forum in talking about our gear, say, features, specs, pros and cons, field performance and accuracy etc. then you just jump out to reply: "your photos are sucking, pls shut up." Then this is a totally irrelevant and off-topic post. Of course, it is useless. What you are talking about is just what Ken Rockwell had told us long ago: measurbators don't take photos and they wasted all their time in measurbating; and; even they attempt, their photos suck. What's actually new here? Nothing.

09-11-2007, 08:00 AM	#91
jeffkrol Veteran Member Join Date: Sep 2006 Location: Wisconsin USA Photos: Gallery Posts: 8,434	Originally posted by RiceHigh Any direct link to be provided? The vacation is a nice one except I was busy enough to visit so many people and places. Hawaii is a good and beautiful place and everywhere are clean. It's so relaxing. People are nice too. Well, for the first time, I haven't brought any Pentax gear. And as such, there was nothing to be rambled about :-) Btw, in the below link are two of the pictures taken from my Hawaii trip. Just look at the two pictures and forget about my article, so as to keep everything good! ;-D LOL.. RiceHigh's Pentax Blog: Underexposure Tendency of K10D and K100D Deflect and change subject.....Quite a pattern. ALSO, all you have to do is take your 5d and k100 and take 1 set of photos, 5d w/ FAKE iso and at 0 EV. K10 at REAL iso value and +1/2 EV.............. Last edited by jeffkrol; 09-11-2007 at 08:17 AM.

09-11-2007, 03:46 PM	#92
Maxington Senior Member Join Date: Sep 2007 Location: Australia Posts: 255	Originally posted by codiac2600 The 40D is more professional than the 5D IMO because the focus is accurate and much faster than the 5D, weather sealed (like K10D from a year ago), Just like to say, the 40D isn't weathersealed like the K10D, its just got a bit of sealing around card and battery if I recall, nothing around the buttons and so on. Its nowhere near weather resistant.

09-11-2007, 05:02 PM	#93
vinzer Veteran Member Join Date: Mar 2007 Location: Philippines Posts: 1,399	Thanks for the laughs RH. You really can't hold a proper debate even if your life depended on it. You could probably make a good scam online dealer, since you're very much into bait and switch tactics. You start off comparing Pentax with the other camera brands (including your beloved Canon), and then a few posts ago you tell jeffkrol to forget about Canon first? Well, sorry, most of us here already are savvy with your posts. It's a great honor that the K10D's still being mentioned alongside the next generation of DSLRs. Don't gripe that the K10D did a clean sweep of the major camera awards, honors given by people who really know what a good camera is (unlike you who's easily swayed by what's popular in the market). With Canon upgrading bodies every year, your camp is bound to win one, eventually. Then again, it's looking like Nikon would win sooner, so why not upgrade your P&S to a D3?

09-12-2007, 01:12 AM	#94
Baffle Inactive Account Join Date: May 2007 Location: Australia Posts: 4	Im sick of seeing this bloke put Pentax down, he must be getting paid to do it! Have a look at his Quality shots taken RiceHigh/Eastern Australia - Photobucket - Video and Image Hosting They might improve now he has a p&s 5d

09-12-2007, 03:18 AM	#95
B051LjKo Junior Member Join Date: Sep 2007 Location: Rijeka, Croatia Posts: 32	Originally posted by Baffle RiceHigh/Eastern Australia - Photobucket - Video and Image Hosting They might improve now he has a p&s 5d Nice pictures there RH, now I can totally understand why Pentax gear disappoints you. Its performance is just to crappy and it is definitly limiting your skill&performance...

09-12-2007, 03:34 PM	#97
vinzer Veteran Member Join Date: Mar 2007 Location: Philippines Posts: 1,399	Originally posted by RiceHigh Did the Pentax user manuals tell us that we need to apply a +1/2EV exposure compensation all the time in order to get properly exposed pictures??? My manual certainly didn't, because I also don't need to. You make a gross assumption that the only properly exposed pictures that are acceptable are the ones that YOU think are properly exposed. Don't be so pompous. The world doesn't revolve around you alone. I doubt you've even gone into the photos section of this forum where you can see perfectly-exposed photos without any EV applied. There is no perfect formula for proper exposure. It's all subjective. You don't like Pentax's default metering? Fine, but don't dictate to us that we all need your proposed +1/2 EV adjustment. Besides, that's why there's an EV compensation (if you wanna get technical, which is what you think you are, the exposure in "EV exposure compensation" is already redundant) - because not all people have the same ideas about proper exposure. Seriously, go back to a point-and-shoot where everything is taken care of for you. The 5D is still too much camera for what you want, and for what you can handle.

09-12-2007, 04:55 PM	#99
equinox Senior Member Join Date: Sep 2006 Location: Canada Posts: 159	[QUOTE=RiceHigh;94658]Did the Pentax user manuals tell us that we need to apply a +1/2EV exposure compensation all the time in order to get properly exposed pictures??? QUOTE] My Pentax does not require full time + 1/2EV, nor my Canon or my Olympus. Of course their are times you have to dial in EV either way to correct exposure on any camera. Photography course 101; I suggest you learn before posting such mistruths as you have no photography knowledge. A poor tradesman always blames their tools,and you consistantly blame something that is a defect of your own making. May I suggest you take up finger painting to get proper exposure, although I bet you would either blame Pentax or screw this up too!

09-12-2007, 07:53 PM	#100
RiceHigh Veteran Member Join Date: Nov 2006 Location: Hong Kong Posts: 1,934 Original Poster	Originally posted by jeffkrol And you cannot read a simple statement by mr. Kerr: 3. The implication of this is that the camera in metered operation will provide an exposure on the sensor about 0.4 stop "hot" compared to what is contemplated by the ISO standards. . . . SNIPPED . . . What more really needs to be said..........Take ALL your exposure data and add 1/2 stop and then talk to me............actually forget it....... I know what Kerr is talking about and I do understand what he talks (which is what you have kept referrring to) but I'm afraid his conclusion has been drawn up too fast. So, I've hinted you to back to the basic, which is the ANSI formula which Doug Kerr has written down for it in his essay. So, let's review the two key points as presented by Doug Kerr: 1. Canon's ISO speed is actually 1/3 stop faster than the true ISO standard, as rated (well, Phil Askey has measured and said the same too); 2. Doug believes that the K factor used by Canon is 12.5 because he measured a value of 12.7 by measuring the Exposure Value and then calculate back the K factor by assuming the value of another "constant"; For those others who read here but haven't come across Doug Kerr's excellent articles, I provide the source links below: http://doug.kerr.home.att.net/pumpkin/Exposure_Calibration.pdf http://doug.kerr.home.att.net/pumpkin/Scene_Reflectance.pdf Now, what Doug has assumed is that his 300D is exposing like film as it should be. However, I would think one-step more deeper. If Canon just wish to make a brighter exposure, what they just need to do is to adjust the K factor of their camera's reflective light meter. They need not to keep 12.5 and also need not to raise the actual ISO sensitivity (which requires tweaking to the hardware amplifier for the CMOS sensor). So, the complicated action done is highly questionable. And, in the old film days, Minolta and Pentax used a K factor of 14 (I verify this in the Minolta pro light meter's user manual - link contained in my homepage but now deleted by the KM already, but I shall provide my direct homepage link for the relevant paragraph below) and Canon and Nikon uses a value of 12.5. A value of 14 means the exposure results will be brighter as the EV and the K are put in inverse positions in the ANSI formula. So, my (maybe wild) guess to this somehow strange phenomenon and design arrangement is that Canon intentionally overexpose the image by +1/3 stop (expose to the right) and then compress the image by underexpose by -1/3 by the DIGIC processor. By doing so, it will always improve S/N ratio of the image and thus less visible noise. So, people will then ask then this would result in highlight overblown? Remember there is a +1/2 headroom for th highlight already with a K factor of 12.5 (which is again smaller than the maximum value ANSI recommended, i.e., 13.6)? So, there is still a 1/6EV "cushion" left. My this proposition explains also why Canon DSLRs are more vulnerable for highlight blowing, just because the cushion has now been set smaller, i.e., from 1/2EV to 1/6EV. But still there is a margin here. As long as the Canon metering and exposure system is highly accurate (my experience is), this "risky" design can work. As for Thom's article, he did in fact over-simplify the case and I had addressed about Thom's article long ago with reference to the ANSI's formula. Despite that you had kept refusing to read my this simple paragraph, I will post the link for others' reading and digestion: RiceHigh's (Pentax) DSLR and Lens Measurbation Page on Exposure Accuracy and More.. So, the basic is all about the ANSI formula, which we should read about. Besides, regarding where the mid-grey is: 110 or 118 (both you have told us) or 128 are not really that important. If you believe my determination of 128 as mid-grey and proper exposure is incorrect, then everyone can read my test results with a 110 lower value in mind as correct to see if the Pentax DSLR system's exposure is consistent or accurate, or not:- RiceHigh's (Pentax) DSLR and Lens Measurbation Page on Exposure Accuracy and More.. Finally, I still wish to remind you that K factor is not equal to reflectance! K=12.5% does NOT imply a light meter calibrated for a scene reflectance of 12.5% - PLS DO re-read the ANSI formula. P.S. I really don't understand why you still cannot discuss on the topic in accordance to the ANSI formula but first reading and understood it before went and go further into the discussion - for so many years! P.S. 2: Doug, Thom, RiceHigh and Anyone can be wrong in assuming anything inside the DSLR black boxes are doing. But, the ANSI formula cannot be wrong!

09-12-2007, 11:24 PM	#102
RiceHigh Veteran Member Join Date: Nov 2006 Location: Hong Kong Posts: 1,934 Original Poster	Mr. 110, Have you read the ANSI formula yet then? Whilst you keep emphasizing the faster ISO speed of Canon DSLRs is a problem, do you think a faster actual ISO of Canon DSLRs will cure the inaccuracy exposure problem of Pentax DSLRs? They are two totally irrelevant cases afterall. Also, how many of the typical DSLR users will use an external meter to meter instead of using the internal meter? If I could use an external meter, actually the exposure problem of the Pentax DSLRs had been resolved long ago - that what I said in my homepage, as I did mention that the ISO speed of my Pentax DSLRs are accurate, as tested. As for Canon's case, it is not very difficult to tackle even if one use an external meter, just dial in 1/3EV less in the camera or 1/3EV more at the light meter for the ISO rating then case closed, e.g., ISO 160 in camera and ISO 200 at handheld meter. As for 110, 118 and 126, 127 or 128 as mid-tone, different people say different values. Doug Kerr writes 118 in one of his articles. A search on the net returns quite some results of 128. You insist 110 and 126 for me (which I have never said 126). Remember the "hearsay" theory of yours? Which one should be correct? And, could you explain to me why 110 should be the mid-grey value?? And why Doug Kerr says 118? You keep saying that 110 = sRGB is meaningless actually. What we need to know is why is that! Any supporting documents which can give us a technical reason for that? (don't give us more "hearsay" links!) Anyway, a histogram at 0 is total dark and 255 is total white. In the middle of white and dark is the mid-tone and that the histogram is linear as percepted by human eyes. What's wrong with 128 as mid-tone? Pls explain. Bottom line: most people says 128 - do a web search and you can see all those photo and technical pages and forum posts. But then the majority could still be wrong anyway. And, YOU may be the ONLY ONE who is correct, hopefully. But since you insist 110, I just try to suggest you (and anyone as well) to try to intrepret my test results in another way. My Pentax DSLRs exposed for the mid-grey (where I metered on) for results that returned the values from 70 something to 130 something, with different lenses and/or different metering modes. And as for the Spot metering, it is often under (less than or far less than 110) But with the Canon DSLR, the results are always close to 128 and well within the 1/3 EV margin. So, if you like darker pictures which are reverted to 110 for your own preference (as you say) that's fine. However, you still cannot get around the 110 most of the time but something varied from time to time. In my book, this is simply called "inconsistency" and actually inaccuracy. Yours, Mr. 128

09-13-2007, 04:03 AM	#103
Chako Inactive Account Join Date: Jul 2007 Location: Sault Ste Marie, Ont, Canada. Posts: 563	I dare say I know more about photography then you do RH. I teach it after all. I will not get into this measurebating debate that seems so pointless and infantile. I will say however, that you should go out and take more photos. From the few photos I have seen posted above, you could use a few pointers on good composition, eye paths, tonality, and the use of the rule of thirds. Only once you have learned the basics, can you break them to good effects. Oh and as a Canon user, I have come across a few posts of him complaining about the 5D on other forums. So folks, we have a person who will never be truly satisfied with his/her gear because the equipment must be at fault. It is easier to blame the equipment then to blame a person’s lack of photographic skills. This is not meant as an insult, although I am sure you must thrive on them by now. Consider it more an honest opinion based upon the few threads I have encountered here and on other forums that I may lurk of a photographic nature.

09-13-2007, 04:31 AM	#105
RiceHigh Veteran Member Join Date: Nov 2006 Location: Hong Kong Posts: 1,934 Original Poster	Originally posted by Chako I dare say I know more about photography then you do RH. I teach it after all. And, please show us your excellent photos, our teacher.