While it is billed as a 14MP camera and seems to do favorably with upsizing, it actually produces 4.6MP output. I'm not sure it is the best for stock for that reason. When you look at the output compared to a downscaled Olympus JPG they are quite close, and the Sigma captures a lot of detail - probably more - but I would check to see how upscaled images are handled at stock companies. You may be limiting sales if you have to upload at 4.6MP. I would highly recommend any of the newer compacts with larger sensors that also take interchangeable lenses (including fixed prime lenses):
Sony NEX-3 and NEX-5
Panasonic DMC-GF1, etc. with 20mm f/1.7 lens
Olympus EPL-1 / EP2 with 20mm f/1.7 Panasonic lens or 17mm f/2.8 lens
For all around stock in terms of price, quality and out of camera jpgs, I think it is hard to beat the Olympus EPL-1 with the Panasonic 20mm lens (plus consider the Olypmus kit lens as a basic kit zoom). It would be more than a stop faster than the sigma, and image stabilized. Going with the Olympus 17mm would be more comparable in price, though.
I personally have the GF1 and use it for stock when travelling and don't want to carry the big SLR - note that I haven't used any of the others for comparision, but the GF1 has a much simpler workflow than any compact I've used.
All of the options above also trump the Sigma by having HD video as well, if you are into that.
Dreamstime may accept upscaled photos from sigma foveon cameras. I have seen several here at 14MP. I am still waiting for sigma to come out with 10MP output sensor not the 4.6MP output they have now. If they do that then sigma has a shot at selling some cameras.
Autoreflex TC 35MM camera and various lenses though I rarely shoot fi...
Quoted Message: Dreamstime may accept upscaled photos from sigma foveon cameras. I have seen several here at 14MP.
You are right - the upscaling for this particular camera (with 3 colors at each pixel) seems to be a non-issue. There aren't too many who list a DP1 in their profile, but those that do have images in the 13-14MP range:
I have a new DP2, I've been waiting for it. I love it. The 14 mp spec is a fair and honest comparison to same spec Bayer sensors. The fovean sensor is three vertically stacked layers, like color film. I think Fovean is better than Bayer layout which only sees one color per sensor. Fovean senses all three colors at a site without interpolating the other color sites. I think Nyquist would say 4.6 M tricolor has same bandwidth as 14M Bayer. Incidentally, the DP2 carries a pro quality lens. B&H sold me the standard kit for $571. Have not had a chance to upload any shots to Dreamstime . . . later. I will still also be using 35 and 120 film when I have the opportunity. I gave my old Nikon L15 to my wife . . . .
Minolta Dimage Scan Dual IV 35 mm 3500 dpi scanner; Epson V500 film s...