It seems they are constantly looking for ways to use weaker AA filters in order to improve sharpness. The trade-off is processing power/time. Either you slow the image processing significantly by doing some of the AA in firmware, or you only do the extra AA in the RAW conversion software.
I think Sigma is RAW only which is why they can do software anti-aliasing. The kodak lessens the problem to start with because it has greater resolution on the sensor. I guess the D70 has a slower frame rate to accommodate the processing, although beefing up the processing power/speed possibly due to better (newer) technology could offset some of that. Every thing I hear is that the D70 is better than the D100 and possibly better than the *istD in terms of resultion - although it is difficult to tell because of the different sharpening effects applied (and regularly debated)... > -----Original Message----- > From: Jostein [mailto:[EMAIL PROTECTED] > Sent: 06 July 2004 17:21 > To: [EMAIL PROTECTED] > Subject: RE: *istD anti-aliasing? > > > Thanks, Rob, > > I too suspected most DSLR's except the Kodaks to be that way. > Not having seen how a 6 Mpix image would look without > anti-aliasing, it makes me wonder. Nikon has apparently > implemented a middle way with D70, doing some of the > anti-aliasing in software instead. > > Here's a quote from Yatish Kumar's review at > http://www.photo.net/equipment/nikon/D70/: > > "Of particular interest is an understanding of image quality > when using RAW NEF files. In order to enter a discussion on > this subject, it is important to understand that Nikon chose > to implement the anti-aliasing function partially in the > softening filter in front of the sensor, and partly using > image processing algorithms after the picture has been taken. > A complete explanation of this can be found at the following > link: > http://www.nikon.co.jp/main/eng/portfolio/technology_e/image_p > rocessing_e/index.htm." > > From the examples given by Kumar, it seems to be a good > solution for sharpness. > > Jostein > > > Quoting Rob Brigham <[EMAIL PROTECTED]>: > > > Isnt this the way they (DSLRs) all work? Except the full > frame Kodak > > jobbie which has no AA filter (and has problems with moire etc as a > > result I believe). > > > > > -----Original Message----- > > > From: Jostein [mailto:[EMAIL PROTECTED] > > > Sent: 06 July 2004 15:54 > > > To: [EMAIL PROTECTED] > > > Subject: *istD anti-aliasing? > > > > > > > > > Gang, > > > > > > After a chat with a pentax guy today, I got the impression > > > that the *istD doesn't use much firmware antialiasing, but > > > rely on a softening filter in front of the CCD to avoid > > > jagged edges. Does anyone have any other info on this? > > > > > > > > > Jostein > > > > > > > > > > > > > > > > > > ---------------------------------------------------------------- > > > This message was sent using IMP, the Internet Messaging Program. > > > > > > > > > > > > > > > ---------------------------------------------------------------- > This message was sent using IMP, the Internet Messaging Program. > >
