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03-25-2010, 08:13 PM   #421
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QuoteOriginally posted by audiobomber Quote
I'd have to see some proof of that. I own both but I haven't had time to test. I'm thinking 2/3 stop, maybe a full stop.
Yea you may be onto something with that statement. I've been running trials and results seem to be little trickier to substantiate than I had thought.

The biggest issue is due to the effect noise has on an image. That is to say that a seemingly slight difference between both camera's would become significant at the next ISO stop and so on and so forth.

Having said that, based on my findings, I'd say that the differences between the two units at ISO3200 seems to be about 1/2. Whereas ISO6400 would seem far more significant in that respect.

Having said that, though I was able to clean-up both images(nicely), I found the Kx to retain much more detail than the K20D in the end mainly due to the gentler noise patterns of the Kx. Whereas the K20D noise has already taken hold of edge contrast and other areas of detail throughout the image.

03-26-2010, 04:31 AM   #422
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Pushing the limits

Tried out my Kx at ISO 12,800.
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03-26-2010, 06:06 AM   #423
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Low light @ISO 6400


@ISO 12800


All shoot in raw with NR off, only corrected WB in post processing
03-26-2010, 09:20 AM   #424
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QuoteOriginally posted by audiobomber Quote
Hmm, I see noisier grey but cleaner black and more detail in the stamp in the K20D photos.
Also, if you want apples to apples, you've got to compare *at the same size*. Any image looks noisier the larger you view it.

I've looked at more comparometer images than I care to admit. Even wasted a few minutes a few minutes of my life and some paper *printing* a couple of the images. My take is that the difference between *any* of these cameras is fairly inconsequential in the real world.

03-26-2010, 01:53 PM   #425
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Well, yesterday I was able to REALLY test a K-X at high ISO and there's no question that it's a lot better than my K10d at ISO 800 and 1600. However, there're other things about the K-X that I didn't like.....so I will wait for a "K-5".

Kind regards
.lars
03-26-2010, 09:58 PM   #426
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QuoteQuote:
Marc Sabatella:

Also, if you want apples to apples, you've got to compare *at the same size*. Any image looks noisier the larger you view it.

I've looked at more comparometer images than I care to admit. Even wasted a few minutes a few minutes of my life and some paper *printing* a couple of the images. My take is that the difference between *any* of these cameras is fairly inconsequential in the real world.
I think you are right once again. "Apples to Apples," though sounding real good in theory, it is just that------ theory. Reality is a whole other matter. Yes, the differences between any of these cameras is inconsequential in the real world. + 1 to you Mark!

Also, at the size we are displaying pics here, one could upload high ISO shots from their old Panasonic Point & Shoots (notorious for lousy high ISO) and they would blend right in.
03-27-2010, 05:33 AM   #427
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Picture edited, check further down

Last edited by melander; 03-30-2010 at 11:24 AM.
03-27-2010, 02:46 PM   #428
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I guess I don't shoot concert photos, so I don't ever feel it necessary to push iso up to the same level that some do. I have said before, the issue that I have with high iso is not noise it is reduced dynamic range. If you could take the same photo at iso 100 and iso 3200, even if the noise is about the same, the iso 100 photo will look better (assuming it is a scene that will tolerate a slower shutter speed).

This is my daughter at iso 3200 with the K7 and the DA 70.



03-27-2010, 05:22 PM   #429
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NR "off" ?

QuoteOriginally posted by Jewelltrail Quote
What I love about my K20d, is I can shut off NR, shoot Raw, and then decide for myself if any NR will be applied with 3rd party software, which produce better results anyway. I like some grain in my high ISO shots, especially when more detail is preserved.
Jewel, how do you shut off NR on a K20? I know you can shut it off in the in-camera conversion RAW>TIFF/JPEG but I thought it was only for that process? As far as I know, a set amount of NR is "hard wired" in and it can be minimized in Camera RAW processing, it's always there. Am I wrong?
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03-27-2010, 05:27 PM   #430
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The RAW processing that occurs for RAW at high ISO on all Pentax DSLR's cannot be turned on or off - it's simlpy there, always, if the ISO is high enough. The specific cutoff varies from model to model. Since it's already there in the RAW data, it's there regardless of whether you convert your RAW file with ACR, with PPL, with some other program, or even if you actually shoot JPEG. If someone says they have turned NR off, they mean, the *additional* NR that the camera can optionally do for JPEG if you set the appropriate option. That setting has no effect if you shoot RAW.
03-27-2010, 07:54 PM   #431
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QuoteQuote:
FH Photographer:Jewel, how do you shut off NR on a K20? I know you can shut it off in the in-camera conversion RAW>TIFF/JPEG but I thought it was only for that process? As far as I know, a set amount of NR is "hard wired" in and it can be minimized in Camera RAW processing, it's always there. Am I wrong?
Brian
In my post above I did qualify this with:

QuoteQuote:
Jewelltrail: I shot the image with NR off in the K20d, though I think, automatically, when shooting @ 3200 ISO, the K20d adds a minimal NR anyway.
See pp 80, and, in particular, the "memo" on p78 pf the K20d Manual. These are the words I find most important:

"[I]Noise reduction is set to [Strong] when shooting with a sensitivity of ISO of 3200 or higher, regardless of the [18 . High ISO Noise Reduction] setting 9p.800 in the [C Custom] Menu."

The trouble with the Manual is it is not clear enough, specifically for NR applied to jpg vs. Raw images. There has been some debate concerning this at our forum, especially when the K20 was released. I still have not read anything definitive, from Pentax, on precisely how NR is alocated.

However, there can be no doubt that the amount of auto NR applied in Kx images far exceeds that in K20 images. Another thing which complicates the NR, are the 2 settings ("Auto" & "On") for slow shutter speeds.
QuoteQuote:
Marc Sabatella The RAW processing that occurs for RAW at high ISO on all Pentax DSLR's cannot be turned on or off - it's simlpy there, always, if the ISO is high enough. The specific cutoff varies from model to model. Since it's already there in the RAW data, it's there regardless of whether you convert your RAW file with ACR, with PPL, with some other program, or even if you actually shoot JPEG. If someone says they have turned NR off, they mean, the *additional* NR that the camera can optionally do for JPEG if you set the appropriate option. That setting has no effect if you shoot RAW.
Marc, I have read this before--this is one of the theories, but not the only one. I have not seen this confirmed by Pentax though. I have also read a theory which says Raw files are completely unaffected by NR--which I am also yet to see confirmed. I know when I shoot Raw with NR off in #18 of Custom Settings, my images look very much unaffected by any NR. For example, here is a %100 crop shot with NR set @ "weakest" in #18 of Custom Settings. No other NR applied, just re-sized Raw: ISO 3200



Do you have any sources which can confirm what you have written here? I hope so, it would end a 2-year old mystery for me.

Last edited by Jewelltrail; 03-27-2010 at 08:19 PM. Reason: clarity
03-28-2010, 09:18 AM   #432
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QuoteOriginally posted by Jewelltrail Quote
Marc, I have read this before--this is one of the theories, but not the only one. I have not seen this confirmed by Pentax though. I have also read a theory which says Raw files are completely unaffected by NR--which I am also yet to see confirmed.
I doubt Pentax would confirm that they use NR in their RAW files. But note that RAW files *are* completely unaffected by the NR setting you make in camera - that much *is* true. As I said, the NR that the camera does for RAW at high ISO is independent of the camera settings - it is there always a high ISO.

QuoteQuote:
I know when I shoot Raw with NR off in #18 of Custom Settings, my images look very much unaffected by any NR.
No one ever said it was a *lot* of NR. But if you're looking for eveidence, search dpr for posts on the subject by GordonBGood. He' got his own software for analyzing RAW data and first became of the patterns that way, but since no one else really knows anything about how his programs work, not everyone was convinced at first. More recently, he has taken to posting large histograms (as GIF files, so the file sizes are still small) that show the effect in ways that pretty much anyone can see. This is possible because of another fact: higher ISO's on these cameras are implemented by a simple digital "push" of the ADC output, rather than actually turning up the gain on the amp. Meaning that without NR, you'd see "holes" in the histogram (multiplying all values by 2 to push one stop means no odd numbers in the histogram). Applying NR smooths some of these holes, but still shows the sign of their presence pretty clearly.
03-28-2010, 08:41 PM   #433
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car show ISO 1600

A few pics taken at our local car show. The Fonz (Henry Winkler) was there.
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03-30-2010, 11:25 AM   #434
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Pentax K-X, Iso 12800, Voigtlander 180/4@4 Lightroom 3b2

03-30-2010, 12:41 PM   #435
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Sweet output!

I would LOVE to see what the LR3 Beta RAW processor could do with such an image.
Also... I'd run it through a debanding plugin to see what that does too.
But LR3 ... crazy NR engine in that one... just crazy
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