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04-01-2007, 07:59 PM   #46
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Oh thanks, I hadn't realized that I had phrased that question poorly, yet, you answered what I wanted anyway.

I should've phrased it "Could this issue affect the K100?"

Thanks for the answer.

04-01-2007, 08:30 PM   #47
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There must be some kind of way out of here...

Both Dylan and Hendrix; but the reference is to something much more recent...

Trolling really; for like minded people.

The signature doesn't allow a proper phrasing which involves 4 of something then a fifth and a very leading cliff-hanger video image and the entire song set to an excellent ethereal sound track.

Read the signature like four voices:

There must be some kind of way out of here

...Said the joker to the thief

. . . There's too much confusion

. . . I can't get no relief...


And it helps if you hum the missing music when you reach the end of the text.

And that is just to damn big a hint!
04-01-2007, 09:23 PM   #48
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Issues

The problem with V/HPN (or FF/BB issues or any of the banding threads) may actually be the internet.

Front focus and back focus are terms used by large format photographers for an entirely different matter.

Some careful searching turns up a lowly Canon user with a customer service complaint that involves some perceived mis-focusing issue, bad repair response, a slew of snailmail exchanges, an escalation of the situation, some back slapping and glad handing, that damn focusing chart and the users willingness to spill all the dirty laundry into the public domain of the internet.

That was Pandora's box for the FF/BF issue and every half-baked wannabe engineer started experimenting (I use this term very loosely) with auto-focus on their own cameras and the rest is tortured history.

The truth with FF/BF is that one must operate the camera significantly outside normal conditions for auto-focus and metering, employ a chart that violates many of the 'auto-focus fails here' rules listed in the manual, and have a pretty poor understanding of optics and light to 'see' that failure.

I won't comment further, regardless of who comes screaming--that's the way those that 'see' the issue deal with those that don't or who don't have problems and state same. They shout them down with disparaging labels like fanboy etc. I can ignore them.

Banding in the larger sense, as in wide bands of improperly converted data has been addressed and probably was a manufacturing shortfall---it's solved, so what??? Hey, snot happens!

V/HPN issues are the latest matter. I'm not about to spend good money chasing the IEEE papers that detail the condition. And that's for two reasons: I don't see the problem and I've underexposed/overdeveloped several hundred digital images in the last few days to prove I don't see it. I've had three other dSLR users-P,C & N shoot an extra 300+ images for cross comparison too-they don't have it either!!! A full gamut of subjects, pushes from 1 to 5 stops.

And frankly, I know Push/pull techniques of photography: and I have approximately 50,000 film images (B&W, slide and color PRINT-about 7500 published) to prove it! Home developed for the majority, carefully noted in several dozen spiral bounds.

And the second reason: The IEEE papers have a synopsis that one reads to determine paper content. We, as users don't have access to the specs for the chips-namely voltage and current values. All the 'public' numbers in these papers speak in relative terms-specifically a -60db difference between the optical signal and the chip bias current. Without knowledge of the actual operating voltage/current it would be a guess as to weather the V/HPN effect occurs in the range of voltages/currents of normal image signals generated by normal operation of the camera. Or if extra-normal pushed(underexposed) capture works in the range or the problem area.

Heck, we don't even know for certain if the problem chips are actually making it into the camera--they could have been superseded before production even started!!!!

From empirical testing, I would tentatively say there is no correlation between the V/HPN of the engineers and what we as photographers see. Or more succinctly: some people need to learn proper exposure and RAW conversion along with more mainstream editing techniques; they are mucking-up their own photos from ham-handed editing.

I could go on and on and on, for instance the yellow light metering problem. That one is almost too easy: yellow light isn't quality light-it's all one small band of emissions/frequencies, at low intensity; why would anyone expect the meter to function properly in such a region?

This will be my last post in 'technical' areas like those discussed above. I'm probably qualified to understand and capable of doing such technical things but I'm not fully up to speed with the pentax cameras--I don't work for Pentax. And I don't want to be unless they have some spare cash around to pay for my services.

Read your manuals, use your camera(s). If you find something that doesn't work properly, and you have tried to make it work properly ( to your best understanding) but it doesn't, call Pentax and discuss it with a real technician. I for one won't be around to 'consult' through any forum on such matters[--I'll still help with photography.]

Do threads like this help and/or should we have a spokesperson voice our concerns: NO and NO! The reasons are stated and obvious!

We're photographers, we take photographs; we should continue to do that until something actually happens to SIGNIFICANTLY impede that task.
04-01-2007, 09:28 PM   #49
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QuoteQuote:
My native color setting in ACR is Photolab, so is my color space in PS. The results since doing so have been outstanding. I could not believe the improvement in rendition on all levels. I was surprised as I expected a subtle difference, but not at all. I keep everything in 16 bits right up to the end of the PP process.
Ben in ACR CS3 Beta (CS2 also) I have four choices in color space:

AdobeRGB
ColorMatch
ProPhoto RGB
sRGB.IEC61966-2.1

Is Photolab and ProPhoto one in the same?

I have been using AdobeRGB as the K10D captures in this color profile. I have never been particularly fond of AdobeRGB because it shifts the images to far red. For my tastes sRGB actually retains a better color fidelity. I have been interested in the CIE RGB profile as this is an old printing standard that was set up in France in the late 1920's. CIE RGB has a wider gamut than AdobeRGB but retains much better color fidelity.

I would love to work straight from ACR using CIE RGB. My general question to anyone that may be able to answer it how can you get ACR to give the option to work in CIE RGB or any other icc profile for that matter other than the ones listed above.

As for VPN I do believe it is a direct result of underexposure and pushing the file beyond it's limits. Proper exposure is key to excellent results. There is one quick easy and fast way to get rid of VPN HPN color noise in general: Convert to B&W.

04-01-2007, 09:32 PM   #50
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Well Said, John!

Well said, John. Hear, hear!

QuoteOriginally posted by jfdavis58 Quote
The problem with V/HPN (or FF/BB issues or any of the banding threads) may actually be the internet.

Front focus and back focus are terms used by large format photographers for an entirely different matter.

Some careful searching turns up a lowly Canon user with a customer service complaint that involves some perceived mis-focusing issue, bad repair response, a slew of snailmail exchanges, an escalation of the situation, some back slapping and glad handing, that damn focusing chart and the users willingness to spill all the dirty laundry into the public domain of the internet.

That was Pandora's box for the FF/BF issue and every half-baked wannabe engineer started experimenting (I use this term very loosely) with auto-focus on their own cameras and the rest is tortured history.

The truth with FF/BF is that one must operate the camera significantly outside normal conditions for auto-focus and metering, employ a chart that violates many of the 'auto-focus fails here' rules listed in the manual, and have a pretty poor understanding of optics and light to 'see' that failure.

I won't comment further, regardless of who comes screaming--that's the way those that 'see' the issue deal with those that don't or who don't have problems and state same. They shout them down with disparaging labels like fanboy etc. I can ignore them.

Banding in the larger sense, as in wide bands of improperly converted data has been addressed and probably was a manufacturing shortfall---it's solved, so what??? Hey, snot happens!

V/HPN issues are the latest matter. I'm not about to spend good money chasing the IEEE papers that detail the condition. And that's for two reasons: I don't see the problem and I've underexposed/overdeveloped several hundred digital images in the last few days to prove I don't see it. I've had three other dSLR users-P,C & N shoot an extra 300+ images for cross comparison too-they don't have it either!!! A full gamut of subjects, pushes from 1 to 5 stops.

And frankly, I know Push/pull techniques of photography: and I have approximately 50,000 film images (B&W, slide and color PRINT-about 7500 published) to prove it! Home developed for the majority, carefully noted in several dozen spiral bounds.

And the second reason: The IEEE papers have a synopsis that one reads to determine paper content. We, as users don't have access to the specs for the chips-namely voltage and current values. All the 'public' numbers in these papers speak in relative terms-specifically a -60db difference between the optical signal and the chip bias current. Without knowledge of the actual operating voltage/current it would be a guess as to weather the V/HPN effect occurs in the range of voltages/currents of normal image signals generated by normal operation of the camera. Or if extra-normal pushed(underexposed) capture works in the range or the problem area.

Heck, we don't even know for certain if the problem chips are actually making it into the camera--they could have been superseded before production even started!!!!

From empirical testing, I would tentatively say there is no correlation between the V/HPN of the engineers and what we as photographers see. Or more succinctly: some people need to learn proper exposure and RAW conversion along with more mainstream editing techniques; they are mucking-up their own photos from ham-handed editing.

I could go on and on and on, for instance the yellow light metering problem. That one is almost too easy: yellow light isn't quality light-it's all one small band of emissions/frequencies, at low intensity; why would anyone expect the meter to function properly in such a region?

This will be my last post in 'technical' areas like those discussed above. I'm probably qualified to understand and capable of doing such technical things but I'm not fully up to speed with the pentax cameras--I don't work for Pentax. And I don't want to be unless they have some spare cash around to pay for my services.

Read your manuals, use your camera(s). If you find something that doesn't work properly, and you have tried to make it work properly ( to your best understanding) but it doesn't, call Pentax and discuss it with a real technician. I for one won't be around to 'consult' through any forum on such matters[--I'll still help with photography.]

Do threads like this help and/or should we have a spokesperson voice our concerns: NO and NO! The reasons are stated and obvious!

We're photographers, we take photographs; we should continue to do that until something actually happens to SIGNIFICANTLY impede that task.
04-03-2007, 07:15 AM   #51
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thanks for the tip,.... guess I got to change my color work space,
did find an article,....
Color Management for Photographers #006 @Digital Outback Photo

can confirm, that for B&W edits, in 16bit are better,
in the past, some of the plugins I used, did not support 16bit,....

QuoteOriginally posted by benjikan Quote
My native color setting in ACR is Photolab, so is my color space in PS. The results since doing so have been outstanding. I could not believe the improvement in rendition on all levels. I was surprised as I expected a subtle difference, but not at all. I keep everything in 16 bits right up to the end of the PP process.
04-03-2007, 08:53 AM   #52
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Color Space

QuoteOriginally posted by Rico Quote
Ben in ACR CS3 Beta (CS2 also) I have four choices in color space:

AdobeRGB
ColorMatch
ProPhoto RGB
sRGB.IEC61966-2.1

Is Photolab and ProPhoto one in the same?

I have been using AdobeRGB as the K10D captures in this color profile. I have never been particularly fond of AdobeRGB because it shifts the images to far red. For my tastes sRGB actually retains a better color fidelity. I have been interested in the CIE RGB profile as this is an old printing standard that was set up in France in the late 1920's. CIE RGB has a wider gamut than AdobeRGB but retains much better color fidelity.

I would love to work straight from ACR using CIE RGB. My general question to anyone that may be able to answer it how can you get ACR to give the option to work in CIE RGB or any other icc profile for that matter other than the ones listed above.

As for VPN I do believe it is a direct result of underexposure and pushing the file beyond it's limits. Proper exposure is key to excellent results. There is one quick easy and fast way to get rid of VPN HPN color noise in general: Convert to B&W.
Hello Rico;

I work with Adobe RGB in the K10D and in Adobe Camera Raw I use "ProPhoto RGB" The same goes for my color profile in CS2 "ProPhoto RGB"

I hope that answers your question.

Ben
04-03-2007, 09:01 AM   #53
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Yes, Thanks Ben.

04-03-2007, 01:31 PM   #54
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QuoteOriginally posted by jfdavis58 Quote
The problem with V/HPN (or FF/BB issues or any of the banding threads) may actually be the internet.



From empirical testing, I would tentatively say there is no correlation between the V/HPN of the engineers and what we as photographers see. Or more succinctly: some people need to learn proper exposure and RAW conversion along with more mainstream editing techniques; they are mucking-up their own photos from ham-handed editing.

.[/SIZE]
I can understand your frustration and perhaps a little anger (?) on this issue.

And while I respect your 50,000 images let me explain that until you have experienced one form or another of these problems one wouldn't give a rats patutney about the problems....and...perhaps even deny their very existence.

Let me put this issue in perspective here. I know pushing too. I have been doing it for more than 30 years in more exotic films and technical and specialty films than most people even knew existed. I have been a consultant to image capture with Kodak and industrial and medical imaging Corporations . I average well over 1,000 images per day (roughly 10,000,000 in my career) in my specialty and have lectured and consulted on image capture and output for 28 of those 30 years. While I personally had not made the switch to digital until last year, I have watched and engaged digital (as far back as 1994) in my professional imaging work. While I do not personally experience VPN on my K10D I have sure witnessed it in properly exposed images at medium ISO's in other peoples work.

Is it a Pentax problem????...perhaps...perhaps not (to a degree of course) because it may simply be an isolated problem...and no product is perfect. But, ultimately, Pentax has responsibility to investigate these "normal" exposure problems and make right by it. And to their credit...they have and they will continue to do so.

I have experienced HPN (for lack of a better name) and I do know of what I am talking about, what I am seeing, and what I am experiencing. So, the problem is REAL for some people. Furthermore, Pentax knows it is real too. The problem appears idiopathic (of unknown origin) and isolated to be sure but it does exist. Pentax has not been lazy about addressing or investigating it or denying very isolated examples of these phenomenon to those who care to talk with people within the hierarchy of the company.

So, there are problems, they are real though they may be very isolated.

Where you are most correct, however, is that those utilizing the camera (any camera from any camera maker) need to learn the basic mechanics and physics of light and imaging media (sensor in this case and film in standard SLR's) and how to properly expose.
Unfortunately, probably less than 2% of the picture taking public really knows much about, or has been formally educated in photography. To their credit they come to these very forums to learn and put themselves on the line to be judged by their picture taking peers...newbies, wannabe's, semi-pros and pros. I personally feel that those with solid backgrounds and education and those that have learned, by doing, have a responsibility to share their talents and ideas to help others grow and blossom as photographers. Knowledge, or alleged knowledgein some cases, should not be used as an arrogant or antagonistic platform to debase forum members problems or abilities out of hand.

No camera can handle 6 f stops under exposure but a camera should be able to handle the needs of low key imaging. And for the vast majority the K10D will do that well enough. There is no digital camera on the market....none...that can handle gross exposure errors exceeding a latitude of 2.5 stops in any direction off normal and.... even that is being generous. That's why there is such an output parameter like HDR

So, please don't throw the baby out with the bath water. Some people seeking answers here have a legitimate basis for consternation and their frustrations with their purchase.

I look at it this way too: If there were no complaints (real or imagined) what would be the impetus for the evolution and enhancement of a product or for special attention to quality control. None.

So, while you may not have problems (and that's a good thing) others may very well have them. Remember too, that for many the $1K investment in a K10D kit can represent a large part of a persons discretionary spending. Cut them some slack and please try not to lump them as...whatever...simply because they are stirring the cauldron. If it were not for the masses buying this camera those that have training would more than likely not have the K10D in their hands right now.

Just another opinion here.

Stephen

Last edited by SCGushue; 04-03-2007 at 02:36 PM. Reason: text
04-03-2007, 04:50 PM   #55
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Stephen,

That is so-o-o-o nicely and delicately put.

Thank you.
04-03-2007, 04:54 PM   #56
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This is quite a reply John. I wonder if you took the "Sensitivity test" I posted over at DPR?
As your post seem to be a reply to me that would be good to know before commenting.

Here:
Test: Are you VPN sensitive?
Did you see any VPN in any of the pictures?
04-03-2007, 08:31 PM   #57
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QuoteOriginally posted by Rolly Quote
Stephen,

That is so-o-o-o nicely and delicately put.

Thank you.
Rolly,

Thank you very much for such kind and welcomed words.
Appreciated.

Stephen
04-04-2007, 05:38 PM   #58
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One day later and I once again have to ask you John if your post above was a reply to me, or if it was placed there by mistake.
I know you stated that your post should be your last one within this area. Still, it shouldn't be too much to ask to whom you were adressing.
04-05-2007, 09:24 PM   #59
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"No camera can handle 6 f stops under exposure but a camera should be able to handle the needs of low key imaging. "

I have read this "low key" argument with relation to VPN and the K10D several times now, and it seems to me to suggest a fundamental misunderstanding of how to best use the available DR of your camera.

Just because the image consists mostly of tones that are within a limited brightness range, and in the case of "low key" obviously darker tones, does not mean that you have to expose such that they all fall into the "mud" at the low end of the sensor's range.

In fact, exposing this way with any digital SLR just about guarantees that you will have considerable noise in the image, especially at higher ISO settings.

It makes more sense to move the exposure to the right to get more light onto the sensor to get your image into the region where the sensor signal to noise ratio is much better.

You can then adjust the overall levels down in PP to any level you desire, giving you the darker overall "low key" look you want without extra noise.

Of course, I am assuming that "low key" is defined as I described above and that the entire DR of the scene being captured fits well within the DR of the camera, leaving room at the upper end to add exposure without clipping.

So, just because the image is low key does not mean that you have to cram all of image into the bottom 2 - 4 stops of the sensor range. Given this, I fail to see where "low key" shots with the K10D will necessarily have to result in VPN, or that "low key" shots are necessarily limited by the K10D and VPN.

Ray
04-06-2007, 01:40 PM   #60
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[QUOTE=Ray Pulley;44194
So, just because the image is low key does not mean that you have to cram all of image into the bottom 2 - 4 stops of the sensor range. Given this, I fail to see where "low key" shots with the K10D will necessarily have to result in VPN, or that "low key" shots are necessarily limited by the K10D and VPN.

Ray[/QUOTE]

Ray,

If I am reading your statement correctly that is precisely the problem. Low key, to me and most others, does not involve the elimination of midtones or even some highlights. IT does mean, however, that the predominant mood and tones will fall into the sub midtone and visible shadows for delivery of mood and visual impact.

If the minimal midtones and remaining highlights are intact, VPN/HPN should not be present in the shadow. These very real problems are unfortunately encountered by a fair number of forum members.

Contrary to the thoughts of some forum experts, the vast majority of the worlds camera owners do not live in sparkling lands of endless sunshine. Occasionally, we have clients who want moody shots that reflect the ambience of evening, shade or the play between sun and shade. I recently saw a beautiful evening image wherein a major Railway company wanted a beautiful valley shot of their train yards. The light grey colored grain cars, showed clear VPN @ 100 in the normal evening light found in the valley.

Now, granted, maybe these are isolated camera sensors that diverge from the norm, but even on a digital this type of imaging should easily be handled without VPN or HPN.

Stephen
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