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04-26-2012, 03:51 PM   #46
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QuoteOriginally posted by Anvh Quote
Jump from the K20d to k7 was even less, they uses the same sensor...

I didn't even bought the K20D because of his sensor, so k7 wasn't an option either.

I won't get a k3 just for the 24mp but for the manual video control and the "fixed" AF.
Do yuo use K-5 video a lot? I've taken probably 2 short videos with my K-5. for taking memory videos of the dogs, etc I use my little Sony TX-5 Qulaity is great and it continually autofocus. no messing about.

I'd like the K-5 AF to be fixed of course, but not buying 2 new bodies just for that.

04-26-2012, 04:32 PM   #47
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I've posted this in other threads, but for those of you who are against more pixels...

1. Sony may not have enough (or any) 16MP sensors to commit to a full product run by Pentax

2. Pentax needs to compete on specs in order to attract new buyers

3. By the time Pentax is ready to ship the K-5 successor, there may already have been a small revision to the current 24MP sensor, resulting in better measurables.
04-27-2012, 01:50 AM   #48
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QuoteOriginally posted by luftfluss Quote
By the time Pentax is ready to ship the K-5 successor, there may already have been a small revision to the current 24MP sensor, resulting in better measurables.
It is probable already here- the new 24Mpx FF Nikon D600 on the rumour site.. vs 24Mpx APS-C sensor...
04-27-2012, 03:04 AM   #49
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QuoteOriginally posted by Bestzoom Quote
It is probable already here- the new 24Mpx FF Nikon D600 on the rumour site.. vs 24Mpx APS-C sensor...
That's a different sensor though so how can it be an update/upgrade?

04-27-2012, 04:01 AM   #50
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QuoteOriginally posted by Anvh Quote
Noise per pixel goes up but you also have more pixels so average noise actually stays the same roughly, you can check the sensor on DXO and it's very decent sensor the 24mp.
Not exactly true. Smaller pixels means there are less light photons reaching each individual pixel (or technically, the sub-pixels). Less photons means higher noise, all other things being equal. It does not matter that there are more pixels, unless you are averaging pixels together to remove noise (smoothing), in which case you lose the advantage of having smaller (and more) pixels in the first place. So there is a point of diminishing returns as pixels get smaller. With current technology, the limit is roughly where we are today, that is 16-18 Mpix in APS-C size format. A 24 Mpix APS-C is going to be a downgrade in almost every way compared to a well-executed 16Mpix APS-C design, like in K-5. Only under ideal lab conditions with good lighting will the 24Mpix APS-C outperform a 16Mpix APS-C, and it will take very good glass to do it. It will lose compared to 16Mpix when lighting is low or higher ISO is needed.

I work in medical X-ray imaging and have intimate knowledge of this stuff as an engineer, we have very much the same issues. Both X-ray and light are dealing with photons, and how to best capture them to create an image with good fidelity while keeping noise to an acceptable value. One significant difference is that in medical imaging, higher noise can be tolerable because we are not trying to create esthetic images, as in photography. Plus we are concerned only with capturing one "color", so there is no RGB Bayer type sensor structure.
04-27-2012, 04:22 AM   #51
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QuoteOriginally posted by cbope Quote
A 24 Mpix APS-C is going to be a downgrade in almost every way compared to a well-executed 16Mpix APS-C design, like in K-5.
The DXOMark results are equalized to 8 mp resolution. If you compare the Sony NEX7 to the NEX5n, you will see that your theory doesn't hold up in practice. The noise results are the same for both cameras. The K-5 beats both by a slight margin, but that's only because Pentax does a better job with Sony sensors than Sony does. (K-5 and NEX5n have the same sensor).

Why are you so sure that 16-18 is the peak for APS-C? I read a very convincing argument once that claimed APS-C will max out at about 35mp, and we are on our way there. I wish I'd bookmarked it, because I haven't been able to find the page since then.
04-27-2012, 04:26 AM   #52
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QuoteOriginally posted by Smeggypants Quote
Do yuo use K-5 video a lot? I've taken probably 2 short videos with my K-5. for taking memory videos of the dogs, etc I use my little Sony TX-5 Qulaity is great and it continually autofocus. no messing about.

I'd like the K-5 AF to be fixed of course, but not buying 2 new bodies just for that.
I'm using video more and more.
I'm actually considering the BMC at the moment if video really do get off.

For now the K5 is enough and while K-01 manual controls are nice it's not a deal breaker. I use a grey card and fix exposure and white balance on that so overal lighting between scenes is even enough for what i'm doing now.
04-27-2012, 04:29 AM   #53
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To me videography is a separate hobby, not one I have interest in.

04-27-2012, 04:29 AM   #54
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QuoteOriginally posted by cbope Quote
Not exactly true. Smaller pixels means there are less light photons reaching each individual pixel (or technically, the sub-pixels). Less photons means higher noise, all other things being equal. It does not matter that there are more pixels, unless you are averaging pixels together to remove noise (smoothing), in which case you lose the advantage of having smaller (and more) pixels in the first place. So there is a point of diminishing returns as pixels get smaller. With current technology, the limit is roughly where we are today, that is 16-18 Mpix in APS-C size format. A 24 Mpix APS-C is going to be a downgrade in almost every way compared to a well-executed 16Mpix APS-C design, like in K-5. Only under ideal lab conditions with good lighting will the 24Mpix APS-C outperform a 16Mpix APS-C, and it will take very good glass to do it. It will lose compared to 16Mpix when lighting is low or higher ISO is needed.

I work in medical X-ray imaging and have intimate knowledge of this stuff as an engineer, we have very much the same issues. Both X-ray and light are dealing with photons, and how to best capture them to create an image with good fidelity while keeping noise to an acceptable value. One significant difference is that in medical imaging, higher noise can be tolerable because we are not trying to create esthetic images, as in photography. Plus we are concerned only with capturing one "color", so there is no RGB Bayer type sensor structure.
Yes if you look per pixel but the same amount of light falls on an APS-C sensor as on an ASP-C sensor right, regardless the amount of pixels.
So if you for example look at full screen or print then the difference would be gone, or at least very close.

About the glass, most of my glass out resolve the sensor so that isn't a problem.

Even the kit lens could out resolve 16mp.
04-27-2012, 04:34 AM   #55
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QuoteOriginally posted by audiobomber Quote

Why are you so sure that 16-18 is the peak for APS-C? I read a very convincing argument once that claimed APS-C will max out at about 35mp, and we are on our way there. I wish I'd bookmarked it, because I haven't been able to find the page since then.
Please re-read my comments. I didn't say APS-C will max out at 16-18 Mpix, period. I said "with current technology". In other words, the sensors that are available today and have actually been used in cameras. Sensor technology can and will improve, and light gathering (photon collecting) will also improve. I did not intend to imply that more Mpix will never be possible with APS-C, that is not what I wrote. Please don't read into my comments, take them exactly as they are written

Last edited by cbope; 04-27-2012 at 04:43 AM.
04-27-2012, 04:44 AM   #56
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QuoteOriginally posted by cbope Quote
and light gathering (photon collecting) will also improve.
How will you do that is then my question?
You can't collect more Photons if there only land so many on the sensor, how will you increase that number?


You can actually proof more pixels is actually better.
Take the Q for example and crop the image of the K5 so that it get the same sensor size (in length not pixels).
Wanna bet the Q will out preform the K5 in any way.
04-27-2012, 04:48 AM   #57
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QuoteOriginally posted by Anvh Quote
Yes if you look per pixel but the same amount of light falls on an APS-C sensor as on an ASP-C sensor right, regardless the amount of pixels.
So if you for example look at full screen or print then the difference would be gone, or at least very close.

About the glass, most of my glass out resolve the sensor so that isn't a problem.

Even the kit lens could out resolve 16mp.
If you are viewing the images at 100% (crop or pixel peeping) without any downsizing, the difference will be visible. On images that are downsized, then the noise tends to average out somewhat depending on the amount of downsizing. The more downsizing, the less apparent the noise will be.

Glad to hear you have good glass. I'm still in GAS mode.
04-27-2012, 04:50 AM   #58
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QuoteOriginally posted by Anvh Quote
How will you do that is then my question?
You can't collect more Photons if there only land so many on the sensor, how will you increase that number?
You can't increase the number of photons collected per pixel, but you can collect them more efficiently and with less noise. This is one of the major design points when designing a sensor.
04-27-2012, 05:09 AM   #59
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QuoteOriginally posted by cbope Quote
You can't increase the number of photons collected per pixel, but you can collect them more efficiently and with less noise. This is one of the major design points when designing a sensor.
Do you've any numbers how many photons they collect now, so a percentage.
I thought they pretty much nailed it these days.

But that doesn't change that you're saying that more pixels means more noise in the end result.
04-27-2012, 05:11 AM   #60
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QuoteOriginally posted by cbope Quote
If you are viewing the images at 100% (crop or pixel peeping) without any downsizing, the difference will be visible. On images that are downsized, then the noise tends to average out somewhat depending on the amount of downsizing. The more downsizing, the less apparent the noise will be.
You can make a print without downsizing only difference is that the PPI will be lower with the lower pixel counted sensor.

Look here for example, it's hard to say which one is really better for prints
16mp vs 24mp
http://www.dxomark.com/index.php/Cameras/Compare-Camera-Sensors/Compare-came.../(brand2)/Sony
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