This is a continuation of sort of an existing thread [a href=\'index.php?showtopic=28859\'](here)[/a]. However, since it was started more than a month ago, and was initially about raw converter availability for Canon G10 files, I thought it makes sense to start a new thread about a specific issue related to now available Adobe Camera Raw 5.2, namely its noise treatment.
Over the years I settled on ACR (and Lightroom, as of version 2) as my main conversion engine. I always had Canon DPP and would try it from time to time, mainly for some linear conversions, but since its functionality and interface leave a lot to be desired, it has never become my converter of choice. However, given that until very recently it was the only option for G10, I did develop my first files with it. Then came along ACR 5.2. Having had the same file already converted in DPP, I was surprised to see ACR resulting in a much noisier image. I do understand that "much" noisier is quite subjective, so I will attach some comparison shots for you to decide.
The original shot was at ISO 800, slightly underexposed (exp. adjustment was -2/3) in order to prevent highlights from blowing out. And before you see the grotesquely enlarged grain in the comparison shots at 200%, I want to point out that this post is not about how G10 is noisy... it is not. Even this slightly underexposed shot would print as a decent 8x10, without any external noise-removal software. This is strictly about differences between ACR and DPP.
OK.. to the comparison finally. There are several similar comparisons on the web, notably DPReview of G10 (Section 12: Software & Raw Mode), which typically show two sets of comparisons: one with both noise controls and sharpening at zero, and the second with noise controls at maximum (and sharpening still at zero). While still indicative of differences, such a comparison actually masks one type of noise with another. Hence my first comparison here has chroma noise reduction at maximum, and luma noise reduction at zero (for both files a Neutral Picture Style was used, as any other would introduce even more saturation to chroma noise) . My understanding is, and correct me if I am wrong, that way we are looking at luma noise only. This is a 100% crop, and before you judge the G10 noise harshly, remember that we are looking at an almost 3x4 feet enlargement:
I hope you can see the difference yourself in the above picture, but is is even more pronounced at 200%:
I see here two things: 1. Even with chroma reduction at maximum, ACR still has nasty color blotches visible and 2. DPP noise is much tighter and smaller, almost like what we film dinosaurs used to know as "finer grained", hence creating an impression of a sharper picture.
I have three other combinations at 200% available (i.e., noise zero, noise max, and luma only at max) and will post them in replies if necessary (trying to keep the size of this post manageable).
As I said above, I am a long-time ACR user, hence no agenda here, other than curiosity.
Your comments are welcome and thanks for reading this far :-)