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11-20-2009, 04:28 PM   #61
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QuoteOriginally posted by pcarfan Quote
You got me wrong...I was just talking about the iso performance. I am not going to give up my camera which is better for 99% of my shooting for another that does better just for 1% of the shots I will ever take....No, I am thrilled with my K-7.

Sorry pcarfan, I guess I really got you wrong

11-20-2009, 08:10 PM   #62
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One very specific thing I am noticing with the K7 high ISO pictures is that the details are well preserved.
Is this me or if the details can be saved, even at high ISO, and given that the pics were done in RAW, then this noise thing could be somewhat lessened while opening the RAW file via ACR?
I would imagine that most details would be kept and that this noise would be diminished as well, no?
Any thoughts on that?
JP
11-20-2009, 09:24 PM   #63
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QuoteOriginally posted by jpzk Quote
One very specific thing I am noticing with the K7 high ISO pictures is that the details are well preserved.
Is this me or if the details can be saved, even at high ISO, and given that the pics were done in RAW, then this noise thing could be somewhat lessened while opening the RAW file via ACR?
I would imagine that most details would be kept and that this noise would be diminished as well, no?
Any thoughts on that?
JP
Yep, that's exactly the intended approach. The K-7 defaults to fairly minimal noise reduction for JPEG in the interests of preserving detail, and also provides good scope for noise removal in Raw processing while retaining image detail.
11-21-2009, 01:19 AM   #64
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QuoteOriginally posted by pcarfan Quote
That iso 12800 shot was shot at 1/500" at F4, and that is a bright scene where that iso performance is not that impressive.
Sure, whatever you say. I expect he went from shooing the action to shooting the ref without changing ISO.
He was shooting at an indoor pool lit by whatever lights they use at indoor pools. The light would have been exactly the same as the light for the ISO 6400 shot.

BTW, what does the light level have to do with ISO performance, pray tell?

Brian and I compared files from my K7 to his 7D today, looking specifically at noise reduction.
The Canon is about two stops better than the Pentax.

11-21-2009, 01:43 AM   #65
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Is it about two stops more expensive too?
11-21-2009, 05:17 AM   #66
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QuoteOriginally posted by Wheatfield Quote
Sure, whatever you say. I expect he went from shooing the action to shooting the ref without changing ISO.
He was shooting at an indoor pool lit by whatever lights they use at indoor pools. The light would have been exactly the same as the light for the ISO 6400 shot.

BTW, what does the light level have to do with ISO performance, pray tell?

Brian and I compared files from my K7 to his 7D today, looking specifically at noise reduction.
The Canon is about two stops better than the Pentax.


I was just pointing out the fact that it is a bright scene, but you seem to take it personally....Let me try to answer this with the same tone you are using to communicate..............



Let me quote DPR when they compared RAW noise of the k-7 vs the 7D....." The 50D produces more chroma noise than the EOS 7D at higher ISOs. The Pentax K-7 is still slightly worse than the Nikon and EOS 7D at very high ISOs but the gap is smaller in RAW. At high ISOs the the 7D and its closest rival, the Nikon D300S, are more or less level in terms of chroma noise".............'slightly worse' is a two stop advantage for you and Brain, hah!...what ever you say.....

What difference does a bright vs dark scene make?....Don't you have a camera, and another to boot with your buddy Brian, why don't you take that apparatus and try and see for yourself.....sheesh! If f5.6, iso 6400 and 1/320 is the same light as f4, iso12,800 and 1/500, I don't know what you and Brian will come up with, but it will be fun to see.........so, if you also say two stops, than I guess it is two stops ????


P.S: Do you enjoy reading such tones ? I don't and I sure don't writing it either.

Last edited by pcarfan; 11-21-2009 at 05:48 AM.
11-21-2009, 05:19 AM   #67
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QuoteOriginally posted by jpzk Quote
One very specific thing I am noticing with the K7 high ISO pictures is that the details are well preserved.
Is this me or if the details can be saved, even at high ISO, and given that the pics were done in RAW, then this noise thing could be somewhat lessened while opening the RAW file via ACR?
I would imagine that most details would be kept and that this noise would be diminished as well, no?
Any thoughts on that?
JP
This seems to be the approach that Pentax is taking and has been taking with it's cameras.

It is a huge difference between shooting in Raw and processing vs straight jpeg. With Jpeg the camera is good up to iso 400, not much more.
11-21-2009, 05:43 AM   #68
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I have to say that I think that high iso is abused by novice photographers. Just because you can shoot at iso 3200 doesn't mean that you should. Unless your camera is amazing, your performance in dynamic range is going to drop considerably as you go to higher isos. Sure, there are places where it can and should be used, but in so many places, the photographer could use some bounce flash, open up his lens a stop to shoot at lower iso.

While the kx does look good at high iso, it definitely has some serious noise reduction going on at high isos as well. Can you use it? Yes, but I would reserve it for situations where there weren't any other options to get the photo, other than pushing the iso.

11-21-2009, 07:06 AM   #69
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QuoteOriginally posted by Wheatfield Quote
BTW, what does the light level have to do with ISO performance, pray tell?
For the high end of a camera's ISO range, the signal is likely digitally boosted rather than by hardware - everything
On a K-7, I believe its anything beyond ISO1600, on the K-X it may be beyond ISO 6400.

In such cases, the sensor hardware's output gets no further increase - the signal is just boosted X times as a digital calculation.

If you can get more light on the sensor, the signal-to-noise ratio will improve.
11-21-2009, 07:47 AM   #70
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QuoteOriginally posted by Rondec Quote
I have to say that I think that high iso is abused by novice photographers.
This is a point that I made earlier in the thread. Even Heliphoto admitted that his example shot was "just a quick snapshot" (I'm not calling him a NOVICE since I don't know him). It sure seems that far more people complain about camera gear within the context of taking "just a quick snapshot" than they do if they actually try to take a nice picture using appropriate equipment, technique and processing
11-21-2009, 08:56 AM   #71
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QuoteOriginally posted by fejker Quote
Is it about two stops more expensive too?
That's an apology, not a reason. Where I am, the 7D is about 30% more money and adds a host of improvements to the K-7, one of which is stellar high ISO performance.
I didn't realize this thread was about money, I thought it was about high ISO.
11-21-2009, 09:02 AM   #72
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QuoteOriginally posted by pcarfan Quote
I was just pointing out the fact that it is a bright scene, but you seem to take it personally....Let me try to answer this with the same tone you are using to communicate..............



Let me quote DPR when they compared RAW noise of the k-7 vs the 7D....." The 50D produces more chroma noise than the EOS 7D at higher ISOs. The Pentax K-7 is still slightly worse than the Nikon and EOS 7D at very high ISOs but the gap is smaller in RAW. At high ISOs the the 7D and its closest rival, the Nikon D300S, are more or less level in terms of chroma noise".............'slightly worse' is a two stop advantage for you and Brain, hah!...what ever you say.....

What difference does a bright vs dark scene make?....Don't you have a camera, and another to boot with your buddy Brian, why don't you take that apparatus and try and see for yourself.....sheesh! If f5.6, iso 6400 and 1/320 is the same light as f4, iso12,800 and 1/500, I don't know what you and Brian will come up with, but it will be fun to see.........so, if you also say two stops, than I guess it is two stops ????


P.S: Do you enjoy reading such tones ? I don't and I sure don't writing it either.
I'm not even going to try to translate that into English. At least when I'm being acerbic I'm still able to get my point across.
BTW, my "buddy" Brian has about 50 years of photography experience and has been doing digital imaging since Photoshop 1 was new.
We compared his 7D files to my K-7 files yesterday. What I was getting at 1600 was similar in noise to what he was getting at 6400.
11-21-2009, 09:05 AM   #73
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QuoteOriginally posted by kittykat46 Quote
For the high end of a camera's ISO range, the signal is likely digitally boosted rather than by hardware - everything
On a K-7, I believe its anything beyond ISO1600, on the K-X it may be beyond ISO 6400.

In such cases, the sensor hardware's output gets no further increase - the signal is just boosted X times as a digital calculation.

If you can get more light on the sensor, the signal-to-noise ratio will improve.
This still doesn't answer why the scene brightness would have an effect on noise. All it affects is what shutter speed and aperture you are shooting with at any given ISO.
As I said previously, those shots were done at an indoor swimming pool. I don't know how brightly lit it would be, but probably on par with a gymnasium.
11-21-2009, 09:26 AM   #74
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QuoteOriginally posted by Wheatfield Quote
This still doesn't answer why the scene brightness would have an effect on noise. All it affects is what shutter speed and aperture you are shooting with at any given ISO.
As I said previously, those shots were done at an indoor swimming pool. I don't know how brightly lit it would be, but probably on par with a gymnasium.
Have you ever seen noise on properly exposed/well lit scene compared to one that's not, at same ISO value? Try to shoot something at same ISO at middle of the bright day, and then indoor lit by 100W bulb. Then you'll know.
11-21-2009, 10:19 AM   #75
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QuoteOriginally posted by Jadran Quote
Have you ever seen noise on properly exposed/well lit scene compared to one that's not, at same ISO value? Try to shoot something at same ISO at middle of the bright day, and then indoor lit by 100W bulb. Then you'll know.
So you think daylight and tungsten are equivalent spectrums?
I think I'll bow out of this one now. We've had an official apology based on price, and now someone who doesn't understand tungsten vs. daylight.

Enjoy your discussion.
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