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11-14-2008, 04:05 AM   #151
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QuoteOriginally posted by Wheatfield Quote
I appreciate your attempt.
Thank you for your appreciation.
For everybody not understanding much of what I said... In one sentence it was this:
Good primes outresolve both film and current sensors -- but only having film and current sensors, it is sort of tricky to actually find this out


11-17-2008, 02:03 PM   #152
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UPDATE on noise and pixel density.

More pixels are better and current sensors/processing is better as well.



http://www.dxomark.com/index.php/eng/Insights/SNR-evolution-over-time
http://www.dxomark.com/index.php/eng/Insights/More-pixels-offsets-noise!
This also means that for a 20x30cm print, the image quality of an APS-C camera at ISO200 will be on average equal to the image quality of a full-frame camera at ISO400.

Last edited by jeffkrol; 11-17-2008 at 04:02 PM.
11-17-2008, 03:21 PM   #153
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QuoteOriginally posted by falconeye Quote
Thank you for your appreciation.
For everybody not understanding much of what I said... In one sentence it was this:
Good primes outresolve both film and current sensors -- but only having film and current sensors, it is sort of tricky to actually find this out
Though I didn't understand half of it, I also like how you take the time to explain these things to the rest of us. Always a pleasure reading your posts
11-18-2008, 06:44 AM   #154
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If you like DxO, you should read also this:

Compare cameras

QuoteOriginally posted by jeffkrol Quote
More pixels are better and current sensors/processing is better as well.

SNR evolution over time
More pixels offsets noise!
This also means that for a 20x30cm print, the image quality of an APS-C camera at ISO200 will be on average equal to the image quality of a full-frame camera at ISO400.


11-18-2008, 07:24 AM   #155
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QuoteOriginally posted by RiceHigh Quote
What's your point. As technology progresses things change. If you look at the charts even the K10 beats the 5d in DR at low iso..
11-18-2008, 08:46 AM   #156
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I had already compared the latest D700 to the latest K20D and GX-20 - I don't know if they have the same generation of technology, but surely are the "current" products. Btw, have you actually read already the contents in my posted link before replied and asked?

QuoteOriginally posted by jeffkrol Quote
What's your point. As technology progresses things change. If you look at the charts even the K10 beats the 5d in DR at low iso..
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11-18-2008, 08:52 AM   #157
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Before this becomes another flame war...

Dynamic Range (DR) is one of the most meaningless feature numbers in camera industry. Not theoretically. But practically because of the way it is measured. It basically only measures a vendor's arbitrary choice in mapping raw tone values to 0 ... 255 in JPEGs.
11-18-2008, 08:58 AM   #158
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QuoteOriginally posted by falconeye Quote
Before this becomes another flame war...

Dynamic Range (DR) is one of the most meaningless feature numbers in camera industry. Not theoretically. But practically because of the way it is measured. It basically only measures a vendor's arbitrary choice in mapping raw tone values to 0 ... 255 in JPEGs.
Not really. Its meaningful, highlights and shadows can only be retrieved before those relevant image data are dropped or lost in RAW. If even RAW cannot contain those, where else can?

11-18-2008, 12:45 PM   #159
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QuoteOriginally posted by RiceHigh Quote
I had already compared the latest D700 to the latest K20D and GX-20 - I don't know if they have the same generation of technology, but surely are the "current" products. Btw, have you actually read already the contents in my posted link before replied and asked?
"Current" product is a meaningless term in regards to technology advancements.
Just because a product is current does NOT mean it contains th latest technology. I would think that I wouldn't even have to say this..
AND in regards to the Nikon at 4x the cost it BETTER be better at something then the K20.
AND I will still take the resolution increase over the nikon anyday..... Just me and I know this is a personal choice...



NOTE: I picked the 5d and K10

Last edited by jeffkrol; 11-18-2008 at 01:02 PM.
11-19-2008, 03:44 PM   #160
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QuoteOriginally posted by RiceHigh Quote
Not really. Its meaningful, highlights and shadows can only be retrieved before those relevant image data are dropped or lost in RAW. If even RAW cannot contain those, where else can?
RH, you are partly right. DxO uses RAW rather than JPG most other tests (like DPR) use.
QuoteOriginally posted by dxomark.com:
Dynamic range
Dynamic range is defined as the ratio between the highest and lowest gray luminance a sensor can capture. However, the lowest gray luminance makes sense only if it is not drowned by noise, thus this lower boundary is defined as the gray luminance for which the SNR is larger than 1. The dynamic range is a ratio of gray luminance; it has no defined unit per se, but it can be expressed in Ev, or f-stops.
So, this means that even here, DR still includes influences from (possibly aggressive) noise reduction algorithms which are known to even exist in producing RAW images. I don't say the dxomark results are wrong. I only say that I still have to see the first meaningful test in this regard, i.e., a signal-to-noise ratio curve plotted against spatial frequency and luminance.
11-19-2008, 07:17 PM   #161
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QuoteOriginally posted by falconeye Quote
I only say that I still have to see the first meaningful test in this regard, i.e., a signal-to-noise ratio curve plotted against spatial frequency and luminance.
If I may attempt an elaboration: It is all good and dandy to increase your apparent DR by applying (potentially aggressive) noise reduction even to your RAW data, unless you actually also want to retain detail. In a plot that includes spatial frequency, any manufacturer who sacrifices resolution in order to bump up DR figures, will be found out. I suspect that Nikon's edge partly stems from their noise reduction philosophy, which sacrifices spatial frequency.
12-23-2008, 01:14 AM   #162
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QuoteOriginally posted by Blue Quote
Because I knew you would be in here promoting your anti-pentax blog and talking abut cameras that you don't even own and have limited experience with. If you have used a k20d and Canon Mark III or similar for 4-6 months, I retract my statement.

Also, as pointed out there are a plethora of threads on here about the FF debate.
I found it to be kinda of funny picture. In any case pretty harmless, I donít get why people would get all worked up over it
12-23-2008, 01:17 AM   #163
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QuoteOriginally posted by jeffkrol Quote
So you want to spend 2x as much and yet have the same or LESS resolution as an APS-C camera????
Think you should read this thread and learn what pixel density really means.. Be sure to follow all the links.
Pixel density revisited: News Discussion Forum: Digital Photography Review
As for the evidence, Emil (Emil Martinec) has pointed you to a post of his, there's a long series of posts which you didn't follow, but did discuss and present the evidence in some detail, there's John Sheehy's demonstration under the title 'the joy of pixel density' , and finally there have been extensive discussions of the physics behind it, which back up the position that in theory there is no causal link between pixel density and final image noise content at any given image size (with the caveat that there are noise effects such as random telegraph noise, which come into play at very small geometries). These discussions included a number of people who are research physicists (not me, I hasten to add), and included Eric Fossum.
Your urban legends are showing again.
Re: No really, it isn't: News Discussion Forum: Digital Photography Review
When one does this exercise, it becomes apparent that the main factor in image noise is sensor size. The result is largely independent of MP count for a fixed sensor size. Pixel density, which is sensor area divided by MP count, is poorly correlated to noise because both MP count and sensor size will vary from camera to camera, but only one of those factors is tied to noise level.
Read carefully and you may yet learn weedhopper......
Thanks a lot for pointing to the info provided my Sheeby and Martinec, most illuminating




QuoteOriginally posted by jeffkrol Quote
What's your point. As technology progresses things change. If you look at the charts even the K10 beats the 5d in DR at low iso..
Very interesting as well. I had no idea that eventhough K10 is newer technology, how it would also beat the FF Eos 5D on Dynamic Range at low Iso.

(I know we've had the discussions before, but that doesn't mean that I can't still learn from them)
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