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10-17-2010, 12:53 PM   #31
raz
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MAC can you investigate why the K-5 image look more exposed than the K-7 ? Even the wall behind looks brighter ? My guess is the sensors have different sensibilities , I mean iso 200 is not iso 200 for both sensors, even if the display sais so ?

10-17-2010, 01:25 PM - 3 Likes   #32
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QuoteOriginally posted by raz Quote
MAC can you investigate why the K-5 image look more exposed than the K-7 ? Even the wall behind looks brighter ? My guess is the sensors have different sensibilities , I mean iso 200 is not iso 200 for both sensors, even if the display sais so ?
I just did a quick n' dirty comparison.

With the camera in manual at ISO 100, 5 sec., f8 with all camera settings absolutely identical the k-7 image was noticeably darker, as already observed with most of the shots in this thread. The histograms back up what we're observing. I adjusted the k-7 ISO up 1/3 stop at a time until they appeared to match, and at ISO 160 the histograms are nearly identical.

I'm afraid I've run out of time to do any further testing right now.
Hopefully one of the other K-5 owners here can help answer this.
10-17-2010, 02:02 PM   #33
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Thank you MAC for the answer, your work and pictures placed here are appreciated.
10-17-2010, 02:28 PM   #34
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QuoteOriginally posted by MAC Quote
I just did a quick n' dirty comparison..
Hm, my K-7 ISO 3200 does not look as good as yours...

10-17-2010, 02:47 PM   #35
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This is good stuff, thank you for your effort MAC.
10-17-2010, 05:25 PM   #36
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From my observation I'd say the difference is > 1 Stop and < 2.

But did anyone notice the lose of Dynamic Range in K7 high ISO smaples? There's a MASSIVE lose of DR in the shadow areas after 1600, after 3200 there is no hope/ it's not even funny.

That's what made the K7 high ISO shots looked more contrasty - the shades in the shadorw area are all just clipped.

That is shocking!

I think I'm going to upgrade to K5 when it arrives in Australia...

Thank you for your time and effor OP! Really appreciate it.
10-17-2010, 05:47 PM   #37
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QuoteOriginally posted by Katsura Quote
But did anyone notice the lose of Dynamic Range in K7 high ISO smaples? There's a MASSIVE lose of DR in the shadow areas after 1600, after 3200 there is no hope/ it's not even funny.
True, but this is exacerbated by the K-7's darker exposure in the samples.
10-17-2010, 06:58 PM   #38
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QuoteQuote:
True, but this is exacerbated by the K-7's darker exposure in the samples.
Mmm, I'm not so sure the K7's exposure is that that off/ darker.

Looking at the pictures showing the whole scene instead of the crops, and compare the light areas between the K5 and K7, then compare the shaded areas. I'd say the expore is very close/ certainly within 1 stop? The K-7 maybe underexpose by a tiny little bit. (due to variation between real ISO and indicated ISO???) Maybe we need to feed these into PS and observe the histogram for accurate measures.

But the difference certainly should not make for such a HUGH DR clipping in the shadow area.

Or maybe I'm reading this wrong? If so pls enlighten me.


Last edited by Katsura; 10-17-2010 at 07:04 PM.
10-17-2010, 07:03 PM   #39
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Hi what's the band/ corrupt data looking strip on the left and right hand side of K-5's pictures?
10-17-2010, 09:33 PM   #40
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QuoteOriginally posted by Katsura Quote
Hi what's the band/ corrupt data looking strip on the left and right hand side of K-5's pictures?
Those appeared when I opened up the files in PSP Pro X3. It didn't happen to the K-7 files, so if I had to guess I'd say it's a result of editing the files with a program that hasn't been updated to be compatible with the new camera. As far as I could tell, nothing within the image was changed and it just added a 5 pixel wide strip to the left side, and a 15 pixel wide strip to the right. I was able to successfully crop them out of most of the K-5 samples, must've just missed that one.
10-17-2010, 10:42 PM   #41
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To compare noise, we should use UFRAW or DCRAW without NR in settings and PEF files.
And then compare JPEG results from DCRAW converter. It shows us the real noise of sensors.

Any other comparision is not honest.
10-17-2010, 10:46 PM   #42
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QuoteOriginally posted by MAC Quote
Yes. I did everything i could the second time around to avoid NR
can you simply to upload your PEF files to free uploading server?

as for me, K-7 looks sharper, by the way.
10-18-2010, 04:24 AM   #43
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The K7 actually does better at high iso than most people think. The problem is that if you under expose, even a little bit, and have to bring the exposure up, the photos tend to suffer severely. There is just no head room at all. I would hope that the K5 would give a little bit more leeway for post processing.

The other thing that is mentioned is that the K5 seems to keep dynamic range into high iso shots way better than the K7 does. By the time you get to iso 6400, with the K7, you are pretty much better turning them into black and white photos.

By the way, Ogl, I thought you didn't like the K7. Why are you running down the K5 in comparison with it (particularly since you don't own either camera)?
10-18-2010, 04:59 AM   #44
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QuoteOriginally posted by Rondec Quote
By the way, Ogl, I thought you didn't like the K7. Why are you running down the K5 in comparison with it (particularly since you don't own either camera)?
I also stated that the K-7 low ISO photos are sharper. That's not running the K-5 down, it is a personal observation that IMO everyone here should be able to see. The fact that few have commented on it is disappointing. It's clear that high ISO on the K-5 is better by +/- 2 stops. From these samples, it is not clear that low ISO is as good.
10-18-2010, 05:53 AM   #45
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QuoteOriginally posted by audiobomber Quote
I also stated that the K-7 low ISO photos are sharper. That's not running the K-5 down, it is a personal observation that IMO everyone here should be able to see. The fact that few have commented on it is disappointing. It's clear that high ISO on the K-5 is better by +/- 2 stops. From these samples, it is not clear that low ISO is as good.
I don't think much at all is clear from these low iso samples. I'd rather wait to see some high dynamic range scenes to see what the K5 can do. I am really pretty satisfied with my K7 anyway. However, even at low iso, the K7 has limited ability to pull up the shadows.

There are some people who get too excited about new equipment and others who find fault with everything new. Probably the truth lies somewhere between the two. I'm not getting a K5 right away anyway, but it does look pretty good to me.
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