Another contributor asked if the Comparator was fair/unfair in terms of the resolution and compression settings used for a particular camera.

I'd like to know which file format is being used to store the images used in the review of the DC260. It's well known that JPG's are lossy, even at the highest quality setting. Is the FlashPix file format also lossy? If not, is it comparable to the RAW data format mentioned in another question that was posted?

-- Del Jones (jonesdel@hotmail.com), July 29, 1998

Answers

We used JPEG at highest quality setting for the Comparometer.

Actually, FlashPix and JPEG (probably) end up being the same. FlashPix's default is to use JPEG as the compression engine, although the spec allows other compression techniques as well. The amount of compression selected COULD be different though... We just got our full-production '260 in for testing, and I'll shoot some images in FlashPix format to compare.

The first few cameras we did (Eg, the Oly 220,320,500,600) we posted "high" quality images on the Comparometer, rather than the "Super High" option, as we figured this was most representative of how people would use the cameras. Once we realized how closely people were scrutinizing for JPEG artifacts though, as well as how wildly variable various companies' interpretation of "high" quality was, we began posting only the highest-quality (eg, largest) images in the comparometer page, except for cases such as the res target, where we put up multiple resolutions to make it easier to compare various modes. We now routine capture images in multiple resolution modes for display on the "Pictures" pages, so people can see how image size trades off against quality.

BTW, the ".kdc" format is the old "raw" format used by the earlier Kodak cameras (I think the DC120 was the last that used it, if not, possibly the DC50). Even though I called it "raw", I don't think it was completely uncompressed...

-- Dave Etchells (detchells@imaging-resource.com), July 29, 1998.