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04-26-2009, 02:29 PM   #31
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Max usable ISO is 800???

kristoffon: - First off, I was a bit disappointed by high iso noise. After all the praise for the K20D's sensor and since it has iso 3200 I expected cleaner high iso but it appears to be about the same as the K200D - max useable is 800,.......




K20d, no noise reduction, F9, ISO 1250, 1/1000th, spot metered. I had to resample for the forum, but even the full size is amazingly free of noise.


Last edited by Jewelltrail; 09-25-2009 at 09:08 AM.
04-26-2009, 03:08 PM   #32
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I really try to stay away from subjective discussions such as this one. Jeweltrail, I agree with you all the way on this one. For my uses the K20D's high ISO performance is a gift from heaven but if someone else's experience differs there is not much we can do to change their minds.
Now, I've never shot the K200D but I still have my K10D (and I still use it) and for my applications and uses the K20D is light years ahead of the K10D at high ISO settings. My DA* 300/4 is living on the K20D, usually at ISO800.
04-26-2009, 05:03 PM   #33
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QuoteOriginally posted by Jewelltrail Quote
F9, ISO 1250, 1/1000th
If you're going to keep on this "defend the K20D's high ISO performance at all costs" crusade, you should know that the problem with using images like this as evidence is that they tend to have little bearing on real-world situations. Nobody is going to intentionally shoot a well-lit flower with those settings. A sample that isn't contrived would be more useful. Describing the technique used along with it would even be helpful.
04-26-2009, 09:05 PM   #34
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QuoteQuote:
Quension: If you're going to keep on this "defend the K20D's high ISO performance at all costs" crusade, you should know that the problem with using images like this as evidence is that they tend to have little bearing on real-world situations. Nobody is going to intentionally shoot a well-lit flower with those settings. A sample that isn't contrived would be more useful. Describing the technique used along with it would even be helpful

It was windy in this shoot. I had to get shutter speed up in the 1/1000th range in order to freeze as much motion as possible, while maintaining small aperture for DOF. Even then, I waited a long time to fire the remote in order to get a usable shot. There was nothing contrived here. Can we say S K E P T I C A L everybody???


A picture says a thousand words, indeed.

04-26-2009, 09:23 PM   #35
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QuoteQuote:
Quension: Describing the technique used along with it would even be helpful.
Honestly. nothing contrived about this shot. I truly worked to produce the best possible picture I could given the conditions at the time--this is always my goal.

My technique is limited because I do not have flash. Flash. for Macro in particular, is very needed at times. I was close to the flower, and only taking light from its inside. The wind was blowing & gusting. Yes, it was sunny, but not sunny enough to afford me a small aperture and fast shutter speed (1/1000th range).

I kept trying various combinations of ISO, aperture and shutter speed, hoping to go home with at least one keepsake. So, the technique is simple and straightforward--not contrived--honestly.

I love my K20d and, like Eaglerapids, see its High ISO performance as a "gift from Heaven." My reason for visiting this thread is to try and enable all those who are unhappy with K20 high ISO, to discover a way to maximize its performance, thus becoming happy with the camera. That has been my goal throughout my visit here--I am not here to crusade or argue.

This is an awesome forum, one in which each and everyone of us can learn---but your mind must be open! I guess this is all so ironic, because when I first took a couple of high ISO shots with my K20, over a year ago, I thought--Wow-- this is not good.

But I came to this forum and learned, then went out and practiced. I now can not believe just how awesome the K20's high ISO is. I am hoping that this transformation of perspective and attitude is something which your consciousness makes possible for yourself--Best of luck to you.

Ernest
04-27-2009, 04:06 AM   #36
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Noise tolerance (of people) is very subjective, (visible, noticable) noise showing up in pictures from the same camera at same ISO value varies from picture to picture - so discussions like this are really useless.

Yesterday I downloaded the latest pics from my camera and reviewed them. These were quick snapshots, all at ISO 1250-1600 (couldn't use flash as its batteries were being charged), taken within 1 hour at the same place so roughly under same lightning conditions. Still, some of the pics look great with minimal noise, others look horrible (to me). So even the same person with the same camera can take/have good, acceptable and horribly noisy pictures. It depends on too many things...
04-27-2009, 04:28 AM   #37
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I think that there is no doubt but that you can use up to iso 2000 on the K20 without problem. I personally set the noise reduction in camera to weak. Prior to doing that, there was obvious noise in the darker parts of my pictures.

We need to understand that at high isos, noise reduction will need to happen somewhere. Pentax allows you to make the decision -- do I want to apply it in the camera, or do I want to apply it in post processing? I guess the third option is to have some graininess to your photos. Truthfully, it isn't bad -- I've seen a lot worse when I was using iso 800 film in the "old days," but since digital has arrived, my tolerance for noise is a lot less than it used to be.
04-27-2009, 04:43 AM   #38
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QuoteOriginally posted by Rondec Quote
I've seen a lot worse when I was using iso 800 film in the "old days," but since digital has arrived, my tolerance for noise is a lot less than it used to be.
There it is in a nutshell. We are spoiled now with noise that is so low, compared with film days, we can use extraordinary ISO settings...and still we want more. (Heck, I know I do!)

Personally I enjoy the quality of the noise from the K20D. And I'm glad the camera was designed so that noise reduction is left up to my discretion.

04-27-2009, 05:13 AM   #39
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QuoteOriginally posted by palmor Quote
I'm really surprised by this. I find ISO 1600 and 3200 quite usable with the K20. If you are looking at 100% crops you have to remember that the K20 has 40% more pixels so anything at 100% is going to look worse then it really is. Also, even if the high ISO is the same between the two than that is amazing because of that 40% increase in pixels.

....
John
Hi all

I have been shooting yesterday and for the subject (shooting car races - YEAH, Pentax can do it ) I needed, at least 1000 speed and f9 to f11 aperture.
They were faaaaaaaaaaaaaaaast.
My choice was iso 400 and 800. (15h00 with so so sun)
Mode was shutter priority.
(I have iso reduction OFF on my k20d. )

After the shooting I didn't like some of my images because of the grain (I'm very picky even on details when I look at 100% crops/view ). Then I remmember I had it off.
Went to CS3, noiseware was applied and pictures are fine now.

Maybe I will try to print one to check quality.

About printing, this "grainy" images can be print up to ... ?
Can we dream about 60 x 40 cm ?

I agree with many of you concerning the iso quality. "Problem" is that to use them properly we have to get into it and pratice and of course, know the camera. (I'm doing both )

I will go further and try 800/1600 iso range in the next chance.

Thanks all
04-27-2009, 12:41 PM   #40
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Remember when grain was an intrinsic part of pictures and carefully balanced for effect?

The above was taken with my old Pentax film camera on Kodak silvered film. I like Pentax's digital offerings specifically BECAUSE of the "quality" of their noise, not it's absence.
04-27-2009, 01:38 PM   #41
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QuoteOriginally posted by Jewelltrail Quote
My technique is limited because I do not have flash. Flash. for Macro in particular, is very needed at times. I was close to the flower, and only taking light from its inside. The wind was blowing & gusting. Yes, it was sunny, but not sunny enough to afford me a small aperture and fast shutter speed (1/1000th range).
QuoteOriginally posted by Jewelltrail Quote
It was windy in this shoot. I had to get shutter speed up in the 1/1000th range in order to freeze as much motion as possible, while maintaining small aperture for DOF. Even then, I waited a long time to fire the remote in order to get a usable shot. There was nothing contrived here. Can we say S K E P T I C A L everybody???
True, I didn't consider these conditions at all. Most times I use high ISO are because I'm in non-macro low-light conditions. Many of the clean high ISO shots that get posted seem to be well-lit to begin with. There are always a few excellent low-light ones, but no apparent way to consistently get good results.

QuoteQuote:
I kept trying various combinations of ISO, aperture and shutter speed, hoping to go home with at least one keepsake. So, the technique is simple and straightforward--not contrived--honestly.
Manual mode, I gather?

QuoteQuote:
I love my K20d and, like Eaglerapids, see its High ISO performance as a "gift from Heaven." My reason for visiting this thread is to try and enable all those who are unhappy with K20 high ISO, to discover a way to maximize its performance, thus becoming happy with the camera. That has been my goal throughout my visit here--I am not here to crusade or argue.
It would have been nice if you had started with that, instead of just claiming the OP was wrong

QuoteQuote:
when I first took a couple of high ISO shots with my K20, over a year ago, I thought--Wow-- this is not good.
If you recall the conditions and what you did then, what would you do differently to make those same shots work now?

Last edited by Quension; 04-27-2009 at 01:55 PM. Reason: expand a bit
04-27-2009, 08:33 PM   #42
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QuoteQuote:
Quension: Manual mode, I gather?
Yes, I only shoot in manual--it is basic to my philosophy of shooting.

QuoteQuote:
Quension: It would have been nice if you had started with that, instead of just claiming the OP was wrong
To be honest, I did & still do believe the OP was/is wrong. I have over 1400 posts @ our Forum. In several of them I have addressed this issue. I guess, having spent so many keystrokes on non-essentials, I now go right to my point. But the OP, instead of defending their point, digressed into a meaningless discussion over what is 3200/6400 ISO--all this after the OP said "max usable ISO on Pentax cameras is 800. Clearly, max usable ISO is not limited to 800.

I think, if you are going to make a claim like the OP did. you better be prepared to defend it. The OP never even posted any examples, even after they said they would. You asked my reasoning, so here you have it.

QuoteQuote:
Quension: If you recall the conditions and what you did then, what would you do differently to make those same shots work now?
Actually, I have answered this above: "But I came to this forum and learned, then went out and practiced. I now can not believe just how awesome the K20's high ISO is." I found posts made by Pentaxpoke, and others and read them carefully. That is why I brought back a nearly year-old thread to the forum by PentaxPoke--I hoped it would help the OP to learn--I felt PentaxPoke did a great job explaining his theory. But the OP, instead of acknowledging anything positive in the thread, goes on to argue and hairsplit the definitions of shooting ISO 3200 and 6400. No gratitude whatsoever, never a word that he/she could actually be wrong about their claim, just another argument and digressing discussion of meaningless philosophizing.

Take my pic above and look at its exposure on a histogram. I believe you will see it is exposed very much to the right. There is no real secret--that is all there is to it. The only real trick is balancing the trade off between noise and blown highlights. And, as you have implied already, the strategy works better in some compositions than it others, but IT WORKS.
04-28-2009, 01:06 AM   #43
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QuoteOriginally posted by Jewelltrail Quote
I found posts made by Pentaxpoke, and others and read them carefully. That is why I brought back a nearly year-old thread to the forum by PentaxPoke--I hoped it would help the OP to learn--I felt PentaxPoke did a great job explaining his theory. But the OP, instead of acknowledging anything positive in the thread, goes on to argue and hairsplit the definitions of shooting ISO 3200 and 6400.
No, the OP zeroed in on what PentaxPoke's test was doing, and reached the same conclusions discussed by PentaxPoke himself and others in that thread: if you're adjusting shutter speed or aperture to overexpose at a given ISO, you could just as well reduce ISO instead.

PentaxPoke's initial post started with a film-like mentality, as if ISO was a fixed thing you chose first, which confused people. With digital, normally ISO is the last thing you set and you keep it as low as possible. The discussion that followed clarified that.

QuoteQuote:
Take my pic above and look at its exposure on a histogram. I believe you will see it is exposed very much to the right. There is no real secret--that is all there is to it. The only real trick is balancing the trade off between noise and blown highlights. And, as you have implied already, the strategy works better in some compositions than it others, but IT WORKS.
But you already stated that your shutter speed and aperture were required by the shot, so the only possible way you had to overexpose (so you could pull back in PP, according to the ETTR idea) was to increase ISO beyond appropriate. This is the exact opposite of PentaxPoke's testing approach, and you can't really make any tradeoff between noise and blown highlights, because you increase noise when you increase ISO to overexpose. Assuming you used curves in a way that damped a good section of the left side of the original histogram, ETTR would have benefited your PP technique by having more of the highlight information to spread around, but it wouldn't do much about noise in general.

That doesn't look like an ETTR image to me though, it looks properly exposed to begin with. Either way, as far as I can tell it was the well-lit scene that made it work. That doesn't automatically translate to stellar high ISO performance when many people need it (and therefore test it): for poorly-lit scenes.

EDIT: What I mean by "the ETTR idea" is the technique described here, which requires PP to fix the image afterward. My impression is that you didn't go that far, not that you didn't adjust at all.

Last edited by Quension; 04-28-2009 at 07:13 AM.
04-28-2009, 11:27 AM   #44
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What a sweet image

QuoteOriginally posted by Mister Guy Quote


Remember when grain was an intrinsic part of pictures and carefully balanced for effect?

The above was taken with my old Pentax film camera on Kodak silvered film. I like Pentax's digital offerings specifically BECAUSE of the "quality" of their noise, not it's absence.
Good point. 6 months back, there was a link (perhaps on the dpr site) to a Pentax engineer's discussion about the design goals for the K10. They knew that there would be noise at the higher ISOs, but did some things to make the noise more film like in appearance. At the camera club i belong to, one of the members commented on how nice the grain appearance of some of my pics were, and asked how i did that. I replied that I thought it was just noise, not realizing that Pentax had made an effort to get the noise to have an attractive texture to it, and i have to admit that some noise is not unattractive to me. This guy had a Nikon dslr, if that matters.
04-28-2009, 03:09 PM   #45
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QuoteOriginally posted by Quension Quote
if you're adjusting shutter speed or aperture to overexpose at a given ISO, you could just as well reduce ISO instead.
Not necessarily.

Suppose the camera gives the following exposure readings:

at iso3200: f1.4, 1/100
at iso6400: f1.4, 1/200

Cameras often underexpose and so lets assume that in this case the camera is underexposing by a stop. Underexposed images typically have a lot of noise at high-iso, so both of above shots would have more noise then they should. One option is to give +1EV to iso 6400 shot thus bringing it to a 1/100 exposure, giving it a proper exposure and reducing noise.

This would not be the same as shooting at ISO3200 + 0EV, because the ISO3200 shot at 1/100 would be an underexposed shot, with noise due to underexposure.

A well-exposed higher iso shot is typically cleaner than an under-exposed lower iso shot. Otherwise why would you ever use the higher iso mode.

So yes it is important to expose to the right and give a proper exposure to the image instead of under-exposing it since that induces noise.

Last edited by random; 04-28-2009 at 03:22 PM.
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