On 12 Jan 2002 at 17:40, Frantisek Vlcek wrote: > I have no experience with scanning grainy film at 4000+ ppi, but from > what I read in the thread earlier, the problem was that not a > continuous tone image but a line art image is recorded when the grain > is larger than the CCD's pixel size - either getting moire patterns > or, if the grain is sufficiently larger than pixel size, image without > cont. tone at all - like scanning a magazine page at 1200 ppi.
Hi Frantisek, The situation encountered when scanning large grained films is much like you describe above. > This of > course makes any manipulation like USM, levels, etc very hard if not > impossible. Really it is impossible to apply standard curves and filters, even though there is of course still a range of grays within the image they respond quite differently from a con-tone image under the same action. Median filter would work to make it back into continuous > tone. Or maybe Gauss or other blurring filter. As I understand it, it > has nothing to do with liking or disliking grain, it has more to do > with continuous tone or line art. In such a case, perhaps it would be > better to scan at lower resolution (thus making the grain smaller than > pixel size), producing a continuous tone image, and than blowing it up > via Genuine Fractals or similar software. I have done just this with images requiring a degree of contrast control or level/gamma adjustment, scanning at an appropriate resolution and experimenting will various filters can yield quite good con-tone image capable of producing good output. I have yet to purchase a Genuine Fractals product but I am now quite keen to experiment given some of the positive accounts by members of various photographic lists. Cheers, Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications.html - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
