On Mar 1, 2014, at 2:14 am, Mark C <pdml-m...@charter.net> wrote: > It looks like a 3 or 4 color separation offset print so my guess would be > with Paul that it is a photo of an image printed in a magazine. > > Is the same pattern visible if you look at the print directly under a loup? I > assume it is there. If not it would probably be a scanning artifact.
We had to pop into my wife's work on the way home from her mother's place to check on the leaky roof after a rain storm (it's leaking because it's undergoing repairs). I took the opportunity to bring the slide along so we could look at it under the microscope and we managed to get a photo by holding her iPhone up to the eyepiece. I was skeptical but it came out rather well. This is a crop of the full-size photo to preserve as much magnification as I can get. http://gallery.multi.net.nz/photo/779/ It's a stereo scope so I was able to see that the blue layer is at the bottom, with the green in the middle and red on top. I think the magnification is 100x (10x objective, 10x eyepiece). Plus whatever magnification I'm getting from cropping the phone pic. We couldn't get the 40x objective to focus through the glass but I don't think we needed it. The dark splotch is part of the image. You can just make out the grainy appearance (it was much sharper to the eye). The grain is present even in bright parts of the image but it's incredibly fine even under this magnification. I'm not sure what caused the bleeding between the red bits but it looks like a hair on the image. Here's a link to a smaller thumbnail where you can see that more clearly. That might give a clue to the process by which it was produced. http://gallery.multi.net.nz/img/thumbs/779-sz4pqpbs.jpg Under a 10x loupe I can only barely make out that there are separated primary colours so this detail is is incredibly fine. If it is a photo of a print then it's a really very seriously bloody sharp one. Cheers, Dave -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
