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10-19-2010, 06:13 PM   #61
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QuoteOriginally posted by Rondec Quote
They are getting pretty close. Actually, the really high iso shots look like they end up being 30 megapixels. That is pretty big.
Once you ISO 6400/12800, they're pretty much 30 megabytes each (they're still 16 mega-pixels )

10-19-2010, 08:31 PM   #62
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QuoteOriginally posted by secateurs Quote
"Gordon B. Good went a step further and analyzed the raw histogram in the DNG (cf. link above). His conclusion (which can only be preliminary) is that pixel read-out noise (dark noise) is even less than with the Pentax K-x which excels in this regard. He found too that ISO 6400 is created from an ISO 1600 capture then boosting EV by +2 in camera." - from Falk Lumo -- Pentax K-5 hands-on preview
It was the same even at *ist D. But not 6400. 3200.
"Software ISO"
10-19-2010, 10:00 PM   #63
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processor speed? or dual processors?

Thinking out loud here.

Doesn't the 7D use dual processors to handle the higher frame rate per second? Considering the resources high iso pictures take, that could help with the throughput. Obviously that would also add substantially to the price.

Could this also be the reason for the 25 fps video?

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10-20-2010, 01:04 AM   #64
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Dual image processing CPU's etc would clearly improve camera throughput and 'bandwidth'.

But you don't necessarily need to go down that path. A lot of the options to boost camera fps and the efficiency of the buffer seem very much user tuneable - use fast memory cards, shoot at fast shutter speeds, disable image corrections, disable or minimise any in-camera NR, cap your ISO settings to avoid extreme ISO, shoot JPG, adjust your JPG quality settings, adjust your recorded image dimensions, adjust your 12bit/14 bit colour settings etc.

Even the 7D, with it's dual image processors etc, doesn't perform spectacularly better than the K-5 when trying to handle full size RAW at high fps - it's quoted at 8fps with a 15 shot RAW buffer. But just like the D7000 buffer figures, the 7D buffer and fps values are likely calculated on 100 ISO images only. Shoot those RAW's at high ISO and the 7D fps would slow down a lot.

10-20-2010, 04:29 AM   #65
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So how big is the buffer @ iso 100 or iso 80 ?
Is it 8 images, like the specs says ?
And JPG how is it ? Is it 22 like the english version of the japanese site says ? Or 30 like the Japanese version of the japanese site of Pentax says ?
10-20-2010, 05:47 AM   #66
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QuoteOriginally posted by Priyantha Bleeker Quote
So how big is the buffer @ iso 100 or iso 80 ?
Is it 8 images, like the specs says ?
And JPG how is it ? Is it 22 like the english version of the japanese site says ? Or 30 like the Japanese version of the japanese site of Pentax says ?
At low iso (80/100/200) it is about 8 images... although when I was testing it out I hit 9 a couple times. I found that usually you fill the buffer at full speed, there is a very brief delay and one extra picture is taken and then there is a longer pause while the buffer clears. So I'd call it 8+1

No idea what the limit is for JPG as I haven't tried it.
10-20-2010, 06:03 AM   #67
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QuoteOriginally posted by Priyantha Bleeker Quote
So how big is the buffer @ iso 100 or iso 80 ?
Is it 8 images, like the specs says ?
And JPG how is it ? Is it 22 like the english version of the japanese site says ? Or 30 like the Japanese version of the japanese site of Pentax says ?
I get 27 full-size, highest quality, no processing, iso1600 jpg in a burst.
10-20-2010, 06:05 AM   #68
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QuoteOriginally posted by imtheguy Quote
I get 27 full-size, highest quality, no processing, iso1600 jpg in a burst.
Interesting, and good

I say interesting because I did try a JPEG burst at ISO12800 (to compare to the RAW burst of only 4 images at that ISO). If I recall correctly, I was only able to get 6-7 images in a JPEG burst at ISO12800.

10-20-2010, 06:09 AM   #69
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QuoteOriginally posted by dgaies Quote
Interesting, and good

I say interesting because I did try a JPEG burst at ISO12800 (to compare to the RAW burst of only 4 images at that ISO). If I recall correctly, I was only able to get 6-7 images in a JPEG burst at ISO12800.
Same here. The speed takes a nose dive at iso6400.
10-20-2010, 06:45 AM   #70
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QuoteOriginally posted by imtheguy Quote
I get 27 full-size, highest quality, no processing, iso1600 jpg in a burst.
That's good news...27 continuous frames, or about 3 seconds burst is plenty for me.....
10-20-2010, 07:06 AM   #71
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And when de buffer is full, how fast is the camera then ?
How much fps does it hold ?
10-20-2010, 07:15 AM   #72
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QuoteOriginally posted by Priyantha Bleeker Quote
And when de buffer is full, how fast is the camera then ?
How much fps does it hold ?
From what I recall with RAW files anyway, once the buffer fills up you're done shooting until some space clears... it's not like the speed drops from 7 fps to 3 fps and you can keep going at a somewhat reduced rate. I don't recall how long it takes to clear enough space in the buffer, but I think it's on the order of a second or two (again, from what I recall as I don't have the camera with me at the moment to try it out).
10-20-2010, 07:45 AM   #73
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QuoteOriginally posted by dgaies Quote
From what I recall with RAW files anyway, once the buffer fills up you're done shooting until some space clears... it's not like the speed drops from 7 fps to 3 fps and you can keep going at a somewhat reduced rate. I don't recall how long it takes to clear enough space in the buffer, but I think it's on the order of a second or two (again, from what I recall as I don't have the camera with me at the moment to try it out).
Ah okay.
So that means, that after de 8(or 9) frames you've shot in RAW you're stuck with a camera waiting ? And it is not continous shooting away on a lower FPS rate...
That's not the same behavior what the K20D has for example in my experience...
10-20-2010, 07:54 AM   #74
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QuoteOriginally posted by Priyantha Bleeker Quote
Ah okay.
So that means, that after de 8(or 9) frames you've shot in RAW you're stuck with a camera waiting ? And it is not continous shooting away on a lower FPS rate...
That's not the same behavior what the K20D has for example in my experience...
Again, without the K5 in front of me I don't want to say for certain, but at the very least the FPS drops way down (maybe 1fps?). Hopefully someone with a K5 in their hands can chime in and answer this better. If not, I'll check it out when I get home from work.
10-20-2010, 08:15 AM   #75
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I'm trying to imagine a situation in which I'd be shooting in high-speed burst mode in dim lighting—failing to come up with anything.
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