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10-27-2007, 12:26 PM   #46
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Not A Valid Test Of AF Speed

QuoteOriginally posted by RiceHigh Quote
I found this experiment to be quite interesting and the results and conclusion are rather disappointing (snip)

First, perhaps RiceHigh should have noticed the "tester" quoted on his blog used firmware update 1.20, while only firmware 1.30 adds support for SDM lenses.

Second, RiceHigh makes a big deal on his blog about SDM not being "faster." Pentax said SDM would be fast, accurate, and quiet. Obviously, "fast" does not mean "faster" to anyone with any reasonable level of reading comprehension. And, of course, nothing in his blog proved anything one way or the other regarding AF speed (see next paragraph).

Finally, RiceHigh linked to a discussion in another forum where he claims a "tester" demonstrated that AF is slower. Of course, that is not at all what the "tester" showed. Instead, the "tester" left the lens cap on to simply see how fast the motor turns. Since motor speed is not an indicator of how fast a lens finds proper focus, this is not a valid test of auto focus speed. Further, any test with the lens cap on is clearly not a realistic test of anything in real world conditions.

Sadly, RiceHigh's subject line ("K10D + SDM = ... ") will be prominently displayed in the thread list indefinitely for all to read, while any responses will lay buried under that subject line.


stewart


Last edited by stewart_photo; 10-27-2007 at 01:44 PM. Reason: clarification
10-27-2007, 01:56 PM   #47
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QuoteOriginally posted by stewart_photo Quote
First, perhaps RiceHigh should have noticed the "tester" quoted on his blog used firmware update 1.20, while only firmware 1.30 adds support for SDM lenses.
test with the lens cap on is clearly not a realistic test of anything in real world conditions.
It's the only way to do it. Maybe you should read the test again.

Anyhow, there are many who agrees that the current SDM lenses aren't particularly fast. So regardless how many faults one can find in this test the fact remains, they aren't very fast. And strange as it may seem, it isn't RHs fault.
10-27-2007, 03:11 PM   #48
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QuoteOriginally posted by Gimbal Quote
It's the only way to do it. Maybe you should read the test again. (snip)

Yes, read that and don't necessarily agree. Regardless, it doesn't change the fact that motor speed does indicate how fast a lens finds proper focus, hence is not really a valid test of auto focus speed. Yet this is the very focus of RiceHigh's blog. And this is what I'm disputing, not the speed, or lack thereof, of SDM lenses.


QuoteQuote:
Anyhow, there are many who agrees that the current SDM lenses aren't particularly fast. (snip)

If you read my comments again, you'll see I never said otherwise. I'm not defending the speed of SDM lenses. Instead, I objecting to the flawed interpretation of a test.


QuoteQuote:
(snip) it isn't RHs fault.

Never even suggested otherwise.

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10-27-2007, 04:47 PM   #49
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I am still awaiting an answer to my question - "How much slower is the Pentax Autofocus than canons?" seriously are we talking seconds, milliseconds or nanoseconds?

To ChrisA, Benjikan and the others staking the high moral ground here with Ricehigh - you have never experienced just how nasty this guy can get - I have admitted he has really polished up his act since his early days and plays the smiling well mannered assassin perfectly - it is a pity you can't see some of his early DPR posts and compare them to todays - It is like a totally different person. He also never used to claim to be a photographer - now he claims to have been a photographer for 30 years.

In his early days he at least had his own wacky experiments that he conducted now he simply combs the net looking for little gems of anti pentax sentiment and puts them on a Blog that initially comes across as an informative site on Pentax but every article is about bashing the Pentax brand.

To those whinging and whining Pentax doesn't have a pro model here is my advice, if you are a pro then buy the camera that is going to make it easier for you to make money, it is a tool if you aren't comfortable with it buy another.
If you are an enthusiastic amateur that simply has to have the latest, well Nikon & Canon have exactly what you require buy it and be happy.

As for me I may be rude but I am very happy with my *istDS and I still think the whole Ricehigh blog is very suspicious.

10-27-2007, 05:32 PM   #50
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QuoteOriginally posted by NaClH2O Quote
Why should it cause a problem for me? If you want a $2k camera than why don't you buy an expensive Canon or Nikon rather than pissing and moaning that Pentax doesn't sell one?
Possibly because like me he may have tens of thousands of dollars tied up in Pentax glass that he respects and wishes to use and a only a second rate body on which to use it. We're not all the same hence don't have the same requirements, simple really.

Last edited by distudio; 10-27-2007 at 05:55 PM.
10-27-2007, 05:58 PM   #51
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QuoteOriginally posted by ChrisA Quote
I'm neither defending, nor attacking RH. I don't find his posts irritating, since I'm able to take from them the content I find interesting, and disregard what I do not.

But I find the typical swarm of nasty responses most unpleasant, and its apparent acceptability equally so.
Yes it's pretty sad to see. Unfortunately it seems these days that the way marketeers have pushed personalizing brands has borne a distinct "defend till the death" attitude in the brand's ardent followers. Often any slight towards their brand is perceived as a personal affront, there is now no room for discussion or debate on negative aspects of ones brand.

Over the 10+ years that I've been participating in brand specific fora I've recognized this effect becoming more prevalent. It's a pity indeed.
10-27-2007, 06:06 PM   #52
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QuoteOriginally posted by distudio Quote
Possibly because like me he may have tens of thousands of dollars tied up in Pentax glass that he respects and wishes to use and a only a second rate body on which to use it. Simple really.
Second rate in what way?

The K10D a camera that has been out for a year has proven itself a match for the new 40D from Canon (Canons flagship for non FF) and the D200 from Nikon and very strong indications of new bodies to match or even surpass the Nikon D300. Now it is a probable given that Pentax are not going to get into the FF market in the short to medium term.


So I would suggest if you are a pro your choices are to either store your Pentax glass for a day when Pentax produce a body that meets your standards (whatever they may be) or sell your Pentax glass cut your losses buy what ever camera suits you; make lots of money and be very happy.
As I am sure there will be many Pentax owners who will be happy to buy your glass and use it on their second rate cameras, you may even turn a profit on the sale of your glass.
10-27-2007, 06:19 PM   #53
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QuoteOriginally posted by Falcons Quote
Second rate in what way?

The K10D a camera that has been out for a year has proven itself a match for the new 40D from Canon (Canons flagship for non FF) and the D200 from Nikon and very strong indications of new bodies to match or even surpass the Nikon D300. Now it is a probable given that Pentax are not going to get into the FF market in the short to medium term.


So I would suggest if you are a pro your choices are to either store your Pentax glass for a day when Pentax produce a body that meets your standards (whatever they may be) or sell your Pentax glass cut your losses buy what ever camera suits you; make lots of money and be very happy.
As I am sure there will be many Pentax owners who will be happy to buy your glass and use it on their second rate cameras, you may even turn a profit on the sale of your glass.
Firstly the K10D is not the camera I want, it's just the only one that's available that basically covers my needs. I don't really care how it compares to 40D, D200 or D300 even if it's better. Also why would you assume that any of those cameras would suite me either, particularly given that I indicated that I have Pentax glass? There are a lot of things I don't like about the concept of the K10D and a lot I do, but its main advantage to me is that it has a K-mount, let's just let it rest at that.

Secondly I really hate people telling me what I should do, particularly when it pertains to my finances. I haven't given you advice about your Pentax camera ownership so why do you think it's pertinent for you to do so for me?

It's always easy to tell someone else to "cut their losses" isn't it.

10-27-2007, 06:21 PM   #54
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QuoteOriginally posted by distudio Quote
Yes it's pretty sad to see. Unfortunately it seems these days that the way marketeers have pushed personalizing brands has borne a distinct "defend till the death" attitude in the brand's ardent followers. Often any slight towards their brand is perceived as a personal affront, there is now no room for discussion or debate on negative aspects of ones brand.

Over the 10+ years that I've been participating in brand specific fora I've recognized this effect becoming more prevalent. It's a pity indeed.

You misunderstand (at least me anyway) i am not defending the Pentax Brand I am stating that Pentax at the moment produces cameras specifically for me. The Canon and Nikon entry level DSLR cameras are too expensive for me, the Pentax AF system is perfectly adequate for me and I don't need a machine gun. And the SDM lenses do exactly what Pentax state - they are fast and quiet - and as I stated perhaps not faster than others.

Now if Pentax don't make a camera for you YET - BAD LUCK- go and buy one that makes you happy. From my business experience I will say Pentax can not go toe to toe or dollar for dollar against the Canikon duopoly but they are doing the right thing - producing well built and featured cameras for the consumer market that are priced competitively. If they sell lots of cameras then maybe they will explore the higher level camera market.

Just look at canon I guarantee you that their camera sales in DSLR is shaped like a pyramid with a large strong foundation created from the phenomonal sales of the Rebel/350D without those sales you would not have any high level cameras.
10-27-2007, 07:17 PM   #55
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Tsk..tsk...

Shame on you all, RH is ONLY trying to HELP Pentax. Can't you see that? By continually looking for the smallest and largest flaws he's actually helping ALL OF US who find few or manageable faults w/ our own "gears" to find the error of our ways and to head down the TRUE path of enlightenment and wisdom paved w/ pseudo-science, biased opinions and a dogged stubbornness to NEVER see another point of view. How PURE can you get..
That bit of sarcasm aside I'd like to inject a few opinions of my own.
1) As far as I know Pentax is the ONLY camera manuf that ALLOWS you to even compare a lens w/ 2 seperate drive systems. Maybe if Canon and Nikon had screw drive option's in their lenses we would see the same results. 2) If super duper AF speed is your bag GET a Canon. There system is designed completely different and has some inherent strenths and weaknesses that are just... err.. different. It may be faster but it probably has less to do w/ the motor than the control logic...
Sooo RH show me a test that shows USM motors in Canon are proven faster than a screw drive lens in the same optical cofiguration???????
Get the picture. I think we all have been duped by Canon as to speed...
Give me a Canon white paper on the subject, not hearsay...........
10-27-2007, 09:40 PM   #56
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RH - This is a bit off the topic regarding AF speed but I recently saw your shutter lag testing for various cameras and I have to say that I disagree with the shutter lag times you got. There was professional testing of shutter lag times conducted by an engineer (makes the lightning trigger) and his times for the Pentax cameras even although slower than some top end Canon & Nikon cameras were not far behind. I know this because the lightning trigger relies on shutter lag times in order to capture the lightning and the engineer wouldn't sell me the trigger if the shutter lag time wasn't good enough. Just be careful I guess that if you do testing and then post on the forum your results that later a qualified professional engineer with a lab setup won't tell a different story because it makes your results look a tad strange. Pentax will obviously get new camera bodies in the near future so there's no point in undermining what's out there now when many people love what they already have. I find that for me the Pentax gear is the best buy per $ for those that can't justify spending thousands for the same result. I do landscapes and weddings and I can't tell the difference between photos from my friends Canon 1DS MK11 and a Pentax digital SLR up to sizes greater than A3. The outcome is they pay more for their gear but can't charge anymore for their services. Sometimes the most expensive gear is just overkill. Thats my thoughts for the day.

Tim H
10-28-2007, 05:24 AM   #57
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QuoteOriginally posted by distudio Quote
Possibly because like me he may have tens of thousands of dollars tied up in Pentax glass that he respects and wishes to use and a only a second rate body on which to use it. We're not all the same hence don't have the same requirements, simple really.
Hi,

I'm curious as to which Pentax body ever offered more than the K10 presently does?

Z1-P? I have kept my own all these years but I have to admit the K10 is the better camera for me.

MZ-S? Never tried this one...

?
10-28-2007, 05:50 AM   #58
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QuoteOriginally posted by jeffkrol Quote
Shame on you all, RH is ONLY trying to HELP Pentax. Can't you see that? By continually looking for the smallest and largest flaws he's actually helping ALL OF US who find few or manageable faults w/ our own "gears" to find the error of our ways and to head down the TRUE path of enlightenment and wisdom paved w/ pseudo-science, biased opinions and a dogged stubbornness to NEVER see another point of view. How PURE can you get..
.
Well, he may well be after all...

One thing that I think prompted his scrutiny of the Pentax technology is that he was happy with his previous Pentax cameras (MZ-s I think) and was disappointed by his *istD and then Ds as far as AF and AE were concerned.

One thing he forgot(?) is that, at the same time, the other brands were having the exact same problem:
Try the AF on a Canon D30/D60/10D and even 20D and tell me about accuracy and speed! Try a D70/D100 and tell me about exposure accuracy! Even now, compare the AF speed of a Canon EOS3 with the one of a 5D and be prepared for some deception.

The thing is that in the film days, the strain put on the AF/AE systems was much less.

The precision required to focus with film is much less than for digital, plus, how many tme were you looking at your picture enlarged to the equivalent of 100% view on screen?

ALL brands ran into AF speed/accuracy problems when switching to digital and they are only recovering the same speed their film bodies had. This is also true for Pentax, the K10 is the first to get comparable (better I think) AF speed as Z1P.

For AE, there is no more guy in the minilab (or automatic corrections) to recover less than optimal exposure before printing: you just have to do it yourself.

So basically, RH is right in pointing out that some has been lost in the transition to digital and he is more than welcome to point out the deficiencies of the system but what makes him a bit of a dubious character is that he point ONLY the deficiencies, not the many good things Pentax has to offer.

Another thing I never see him do (not anymore at least) is explain in what way those deficiencies are hampering him, as a photographer, now that would lead to a more constructive argument than "Pentax is lame because they don't have/do this or that like the others".
10-28-2007, 06:01 AM   #59
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Short and Sweet...I hope.

Never had a problem with AF speed shooting fashion in studio or on location...(To Be Sung Loudly) Dah Dah!

10-29-2007, 02:09 AM   #60
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QuoteOriginally posted by ChrisA Quote
I am appalled at the way this forum is so selectively tolerant of offensive language.
A newbie joins up, and people are falling over themselves to say how friendly it is here.
Yet RH posts, and is instantly lynched. The nastiness of the tone in which his respondents post is in my view completely incompatible with a friendly, civilised environment. Yet such lynchings appear to be acceptable to the moderators.
Regardless of how unpopular someone's posts are, they should either be addressed reasonably, or not responded to.
I'm neither defending, nor attacking RH. I don't find his posts irritating, since I'm able to take from them the content I find interesting, and disregard what I do not.
But I find the typical swarm of nasty responses most unpleasant, and its apparent acceptability equally so.
Hey, that's what you get with the attitude he presents.
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