My observations so far (and the laws of physics) indicate that you're partially right:
- If you use a lens that has a max aperture of say f2.8 vs. one with f5.6 and
you shoot at max aperture the f2.8 lens can get +2EV more light on the sensor (if
you reduce your ISO-setting accordingly). That might
lead to less noise.
- If you use a pol- or ND-filter again you lose some light (like up to 2EV). That might
lead to more noise.
- If you convert RAW to jpg a whole bunch of algorithms is applied. Depending on the in-camera processor or the postprocessing sw that you use, there might
be a slight difference in the resulting noise in the jpg. e.g. the more sharpening is applied the more noisy the jpg will become.
- Another source of noise is certainly postprocessing sw. If you sharpen the image, increase the contrast or lighten up dark sections of a pic, you will certainly amplify noise. Also some HDR-algorithms result in an incredible amount of noise (see my examples here: http://www.cameralabs.com/forum/viewtopic.php?t=781
- But I doubt that you can see a difference in Adobe-RGB vs. sRGB
-----Disclaimer: Pls. register all the "ifs" and "mights"-------
Add-on: Don't let them fool you! Even two cameras with identical sensors, like the Sony A100 and the Nikon D80 exhibit visible differences in noise. This comes down to the in-camera sensor-filter and the processing algorithms. So not all "apples" are "oranges"...
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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