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01-29-2008, 10:43 AM   #1
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New Pentax CMOS sensor

Interesting short article on CMOS sensors for DSLR's (including the Pentax K20D) in this week's "Underexposed" column over at CNET
linky:
New CMOS sensors catching on in cameras | Underexposed - CNET News.com

NaCl(hope I posted this in the correct forum)H2O

01-29-2008, 10:49 AM   #2
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so, reading between the lines, CCD has better dynamic range than CMOS?
01-29-2008, 11:35 AM   #3
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QuoteOriginally posted by Gooshin Quote
so, reading between the lines, CCD has better dynamic range than CMOS?
Might be true in general but it seems Pentax has side-stepped that issue with their way of doing things. Here's a writeup of it. http://www.pentaxslr.com/files/scms_docs//K20_sensor_sheet_fR2.pdf I have seen prints showing more detail in how Pentax does things and how it relates to the light entering etc, allowing for more range, but I can't seem to find it at the moment.
01-29-2008, 11:44 AM   #4
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QuoteOriginally posted by Tom M Quote
Might be true in general but it seems Pentax has side-stepped that issue with their way of doing things. Here's a writeup of it. http://www.pentaxslr.com/files/scms_docs//K20_sensor_sheet_fR2.pdf I have seen prints showing more detail in how Pentax does things and how it relates to the light entering etc, allowing for more range, but I can't seem to find it at the moment.
good article but a bit cryptic

Pentax boasts less noise with their CMOS unit, higher resolution, and less power consumption.

no use of the term "dynamic range"

they do say "increased sensitivity to light", but they stick in the word ISO, which negates any assumptions towards increased dynamic range.

hmmm

01-29-2008, 12:01 PM   #5
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QuoteOriginally posted by Gooshin Quote
good article but a bit cryptic

Pentax boasts less noise with their CMOS unit, higher resolution, and less power consumption.

no use of the term "dynamic range"

they do say "increased sensitivity to light", but they stick in the word ISO, which negates any assumptions towards increased dynamic range.

hmmm
I read through the brochure here http://www.pentaxslr.com/pdf/k20.k200brochure.spread.pdf Page 10 makes some reference as well as the odd blurb throughout the brochure.

Though page 12 has what you're looking for.. "Enlargement of Dynamic Range" increased Dynamic Range by 200% - results typical of that only found on film.
01-29-2008, 12:10 PM   #6
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QuoteOriginally posted by Tom M Quote
I read through the brochure here http://www.pentaxslr.com/pdf/k20.k200brochure.spread.pdf Page 10 makes some reference as well as the odd blurb throughout the brochure.

Though page 12 has what you're looking for.. "Enlargement of Dynamic Range" increased Dynamic Range by 200% - results typical of that only found on film.
now i was reading some discussions on that

does this apply to jpegs only, or to raw files as well, does it work with only 1 single photo or does it do some sort of weird doulbe photo thing? (essentialy HDR)

and why is it an "option" and not simply a "sensor with increased dynamic range", i think there is some caveats hidden in the details, otherwise they would advertise it on the first page... 200% more dynamic range than ANYONE ELSE is a big freaking headline!
01-29-2008, 12:25 PM   #7
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QuoteOriginally posted by Gooshin Quote
now i was reading some discussions on that

does this apply to jpegs only, or to raw files as well, does it work with only 1 single photo or does it do some sort of weird doulbe photo thing? (essentialy HDR)

and why is it an "option" and not simply a "sensor with increased dynamic range", i think there is some caveats hidden in the details, otherwise they would advertise it on the first page... 200% more dynamic range than ANYONE ELSE is a big freaking headline!
It's software manipulation, which is why this mode won't happen in RAW.

My guess on what the camera is essentially doing is:
Take 1 raw photo, open 2 instances of it with different exposure compensations, one for optimizing the most shadow detail, the other for optimizing the midtones and/or highlight details. Combine them , and compress them down to an 8bit JPG as output. Very much like an HDR, but with only 1 picture instead of multiple pictures at different exposures.
01-29-2008, 12:28 PM   #8
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QuoteOriginally posted by Gooshin Quote
now i was reading some discussions on that

does this apply to jpegs only, or to raw files as well, does it work with only 1 single photo or does it do some sort of weird doulbe photo thing? (essentialy HDR)

and why is it an "option" and not simply a "sensor with increased dynamic range", i think there is some caveats hidden in the details, otherwise they would advertise it on the first page... 200% more dynamic range than ANYONE ELSE is a big freaking headline!
It is, like page 5 though - "Wider Dynamic Range" - obviously refering to it's predecessor.. Again on Page 10 - "rivaling the detail previously only found in 35mm film"... It seems they chose to announce these features alongside corresponding hardware in the brochure - makes perfect sense to me.

As far as it being JPG only - that makes no sense at all. And I don't think they are being ambiguous in how they're stating things. It's not their character. Take a look at the 20fps - they clearly state at 1.6mp..

Edit: Right. Take a RAW shot and let the camera do it's HDR mojo on it in 'DRE' mode and the result is output as a JPG.. Same as with ANY HDR. Nothing out of the ordinary there and nothing ambiguous at all.

01-29-2008, 01:12 PM   #9
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QuoteOriginally posted by Tom M Quote
It is, like page 5 though - "Wider Dynamic Range" - obviously refering to it's predecessor.. Again on Page 10 - "rivaling the detail previously only found in 35mm film"... It seems they chose to announce these features alongside corresponding hardware in the brochure - makes perfect sense to me.

As far as it being JPG only - that makes no sense at all. And I don't think they are being ambiguous in how they're stating things. It's not their character. Take a look at the 20fps - they clearly state at 1.6mp..

Edit: Right. Take a RAW shot and let the camera do it's HDR mojo on it in 'DRE' mode and the result is output as a JPG.. Same as with ANY HDR. Nothing out of the ordinary there and nothing ambiguous at all.
so then i was right

the sensor does not posses any significant increase in dynamic range.
01-29-2008, 01:33 PM   #10
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Typical CNET review and discussion. Whenever I read a review by CNET, I calculate the exact opposite and go with that conclusion...and usually end up being correct.
01-29-2008, 01:53 PM   #11
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QuoteOriginally posted by Gooshin Quote
so then i was right

the sensor does not posses any significant increase in dynamic range.
No. You are not right. The brochure clearly states "Wider Dynamic Range" in reference to the sensor.. And I was unaware this was some arguement in the first place.. So, stop complaining to me and go buy an Olympus or something..

Yeah - as if the new K20D CMOS sensor is somehow a step back from the K10D CCD. right... :ugh:
01-29-2008, 01:58 PM   #12
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QuoteOriginally posted by Tom M Quote
No. You are not right. The brochure clearly states "Wider Dynamic Range" in reference to the sensor.. And I was unaware this was some arguement in the first place.. So, stop complaining to me and go buy an Olympus or something..
i will buy a K20D regardless. That is not the point.

an article was posted and i made a conclusion that in subtle undertones they were trying to say how CCD has better dynamic range capabilities than a CMOS (regardless of camera brand!)


from the way you were posting, your position seems to be that CMOS would produce better dynamic range.... thats when the argument sort of took place.
01-29-2008, 02:00 PM   #13
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QuoteOriginally posted by Gooshin Quote
i will buy a K20D regardless. That is not the point.

an article was posted and i made a conclusion that in subtle undertones they were trying to say how CCD has better dynamic range capabilities than a CMOS (regardless of camera brand!)


from the way you were posting, your position seems to be that CMOS would produce better dynamic range.... thats when the argument sort of took place.
I'll bet my K10D that the K20D CMOS sensor has better DR than the K10D CCD does..
01-29-2008, 02:10 PM   #14
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QuoteOriginally posted by Tom M Quote
I'll bet my K10D that the K20D CMOS sensor has better DR than the K10D CCD does..
i would sure hope so!

but you are still missing the question i asked

assuming infinite funding, would a CCD produce better dynamic range than a CMOS.


can you please forget about Pentax or Canon or Nikon at the moment, my question is devoid of any reference to manufacturers
01-29-2008, 02:56 PM   #15
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QuoteOriginally posted by Gooshin Quote
i would sure hope so!

but you are still missing the question i asked

assuming infinite funding, would a CCD produce better dynamic range than a CMOS.


can you please forget about Pentax or Canon or Nikon at the moment, my question is devoid of any reference to manufacturers
With infinite funding? No. I really don't think so. The CCD creates too much noise and I think that would effect the total DR. I think if the same infinite funding was put into a CMOS, the CMOS could produce more. Plain and simple, it's a more efficient sensor.

Possibly, the answer may already be here. Have a look at whatever camera has the undeniably most DR - what is it using? Compare that to whatever camera is getting the most DR from a CMOS. How close are they? CMOS is a young technology in this respect and will likely benefit from future development in larger increments.
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