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08-23-2009, 07:04 AM   #1
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K-7 iso 3200 test shots.

For some reason the exif is intact at Flickr yet is not embedded in the links? I opened it in LR 2.4 transferred as a PSD file to CS2 and used Noiseware pro. for NR. Also, colors are sapped in Flickr.

The exposure is iso 3200, F4, 0.3 sec. , needed 1.7 +EV to expose to the right with no clipping in-camera. (so, fairly dark, at f1.9 it would need a 1/13 shutter). I think this is a fair dark frame test.

Tripod, 2-sec timer.

Full Image before NR


Full Image after NR (To preserve detail)


100% crop before NR



100% crop after NR (To preserve detail)



100% crop after NR(remove noise at the expense of detail like some cameras do)


08-23-2009, 07:13 AM   #2
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The very first shot without NR is actually quite impressive for 3200. Once printed you would really struggle to tell.
08-23-2009, 07:18 AM   #3
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Very, very clean ISO 3200 shots.
But that's just 'cause they're perfectly exposed!
Thanks for sharing these - just confirms how good you can get these high-ISO results, though granted, many images needing high ISO will have to have lots of shadow detail, which the noise will be more obvious in...
08-23-2009, 07:20 AM   #4
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QuoteOriginally posted by Ash Quote
Very, very clean ISO 3200 shots.
But that's just 'cause they're perfectly exposed!
Thanks for sharing these - just confirms how good you can get these high-ISO results, though granted, many images needing high ISO will have to have lots of shadow detail, which the noise will be more obvious in...
The nose and the eyes are the darker areas, the brown fur the midtones. But, it is true, that most of the image has no dark shadows.

08-23-2009, 08:12 AM   #5
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Torture test.

Did another test with darker objects. Iso 3200, F4, 0.8 sec. Uploaded to LR 2.4 and recovered some clipped highlights. +2EV. No clipping in camera, but LR showed some.

Full image before NR


Full Image after NR


100% crop of dark areas


100% crop after moderate NR


Aggressive NR like some cameras do at 100% crop.
08-23-2009, 08:23 AM   #6
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QuoteOriginally posted by pcarfan Quote
Also, colors are sapped in Flickr.
You mean they look pale and washed out?

I suspect you've taken the shots in Adobe RBG and uploaded them to Flickr with that colour profile embedded. You need to convert them to sRGB before uploading them for web based viewing.
08-23-2009, 08:29 AM   #7
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QuoteOriginally posted by Big G Quote
You mean they look pale and washed out?

I suspect you've taken the shots in Adobe RBG and uploaded them to Flickr with that colour profile embedded. You need to convert them to sRGB before uploading them for web based viewing.
The first image on my first post looked more sapped out. I am shooting in sRGB and doing work and transferring in sRGB. So, it is staying at sRGB through out. Flickr also seems to reduce the noise a little bit. May be it is not flickr but the JPEG compression that PS is doing. But not a big problem, just a slight color offset.
08-23-2009, 08:49 AM   #8
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Boosting contrast may deepen the shadows and make noise less obvious too.
Still not a bad result at all, even at 100%.

08-23-2009, 09:11 AM   #9
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QuoteOriginally posted by Ash Quote
Boosting contrast may deepen the shadows and make noise less obvious too.
Still not a bad result at all, even at 100%.
Absolutely. I didn't want to do much PP, other than noiseware. But, PP will render perfect images, especially with masking.

Contrast added to dark areas and light area masked, NO NOISE REDUCTION 100% CROP


NR and some more PP



This is why preserving detail at the expense of noise is so important.
08-23-2009, 09:52 AM   #10
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great shots, these should be on review sites that criticize the K-7 for noise at high ISO. I'd like to see how competitors compare with their aggressive NR. IMO NR is always best saved for the powerhouse PC where there is no processing limit on the quality of NR.
08-23-2009, 12:06 PM   #11
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what is the point of using ISO 3200 if you need +2 EV to make it look right? that's ISO 800
08-23-2009, 12:29 PM   #12
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QuoteOriginally posted by Eruditass Quote
great shots, these should be on review sites that criticize the K-7 for noise at high ISO. I'd like to see how competitors compare with their aggressive NR.
Where to begin...
Pentax K-7 Digital Camera Raw - Full Review - The Imaging Resource!

'Competitors aggressive NR' is, I think, not a real issue when you look at RAW output. It is probably the case for in-camera JPEG NR default options though.
08-23-2009, 12:32 PM   #13
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QuoteOriginally posted by k100d Quote
what is the point of using ISO 3200 if you need +2 EV to make it look right? that's ISO 800
LOL. Excellent point.
08-23-2009, 01:02 PM   #14
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QuoteOriginally posted by k100d Quote
what is the point of using ISO 3200 if you need +2 EV to make it look right? that's ISO 800
LOL, No.

Anytime high iso and exposing to the right comes to play, this always crops up.

The consensus is that proper exposure is more important than the lowest iso and then pulling out the detail.

Also, think of it this way. +EV is totally arbitrary. If I used the spot metering, then it would meter off the darker areas and I may have to dial in -EV. So, EV compensation is totally dependent on my choice of metering. In the extreme, the spot metering can be run to the extreme by either getting the meter reading from the brightest part of the image or the darkest.

So, only thing we can do is to expose by the histogram. This is what I kept mentioning as having no clippings. So, +2 EV is irrelevant, what is important is whether the exposure renders the ideal histogram.

So, if I had 0 EV with the chosen metering, then it would mean underexposing the scene by two stops and using iso 800. This will require +2EV in post processing to get the ideal exposure. It is always better to use a higher iso to get proper exposure which will give the least amount of noise than to underexpose and recover which will show more noise. So, using 800 will be the wrong choice.

I knew the +2EV would throw some off, and thus me mentioning histogram, no clippings etc. Hopefully this clears things up for you.
08-23-2009, 01:38 PM   #15
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my concern is only because you have mentioned that you use ETTR technique, which involves overexposing without clipping and then bringing the exposure back down in post which reduces noise.

it is discouraging that you actually had to use +1.7 EV in (matrix metering?) to get an image that bright.

thanks for the tests, the results do look pretty clean.
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