Sigma Noise Comparison: Not Fair part 2

Started Nov 27, 2002 | Discussions thread
OP tom jacobson Contributing Member • Posts: 516
Re: Sigma Noise Comparison: Not Fair part 2

I am not suggesting that Phil has rigged things up to make the SD-9 look better than it should. All this is new stuff and mistakes are easy to make. However, it is clear that we are not comparing apples to apples here. One tends to treat the SD-9 in the league of the 6MP cameras. It is in that league, but only if one interpolates down the 6MP images to match the SD-9 ones or visa versa. The comparisons of noise levels are clearly misleading as they were presented. At equal image size, the SD-9 noise will look very much like the D60's. Add contrast and sharpness, and you have a problem!


tom jacobson wrote:

I have had a chance to study the noise comparisons more carefully
and have found another factor that is throwing the comparisons off.
First, as I mentioned in the first thread, Sigma hides or "masks"
the noise levels of the higher ISO's by lowering overall contrast
and sharpness as you go up in in ISO. This I do not consider "noise
reduction", as you will have "noise enhancement" when you correct
the image to proper contrast and sharpness. Not an effective way
to deal with noise, in my opinion. The second thing that really
throws off the comparisons is that we now
have the resolution factor throwing things off. If you take a SD-9
patch and interpolate it up by a factor of two, you now have a
clumpy noise patch that looks just like the D60, only worse. Phil
mentions that the noise of the SD-9 is finer, and guesses that it
is because of the non-Bayer pixel setup. In fact, it is just that
the noise is not at the same resolution as it is in the D60 patch.
If one were to make a D60 patch half as big, or at equal
resolution, it would also look very fine, like the SD-9 patch.--

-- hide signature --


Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow