John Boudreau wrote:
First of all Michael, that's some nice work, and it's good to see someone else using 100 and 400F!It was your images that inspired me to try it out! As Roland and others have mentioned, the blue "ghosts" do look puzzling, especially when shooting at f/10. Were you using a filter? These "ghosts" appear on all your Fuji 100F and 400F shots, and also on your M17 shot on E200. They really don't look like they are radial in nature, especially in the M17 shot.See my response to Roland. I do not see the ghosts on the film. I made a mistake on the scanner. All of the recent shots from OSP2001 and Table Mountain 2001 were done on a Nikon 4000ED. I got it right on the M17 shot, but messed up on the other three (copied an old page forgot to change the scanner...) And I agree, they do not look radial, instead, they seem aproximately linear. Notice on the M27 shot that on the top of the image they go towards the top of the scan and on the bottom they point towards the bottom. Please note that the frame is cropped somewhat on the top (about 1mm on the film) and bottom (about 5mm). The problem does not happen in the center (at least a severely). Perhaps something to do with how Nikon illuminates the image? I'll try a rescan with the Polaroid as soon as I can rent it again... Then we will have a better idea. Mike I did some shooting with Sean Walker's C9.25 @f/10 earlier this summer on Fuji 400F, using a Lumicon Newtonian Easy Guider. I did not see this ghost problem. For an example I just temporarily posted a full 35mm frame jpg from a 90min shot of M27 (taken with an IDAS filter and unfortunately somewhat underexposed) at: http://people.ne.mediaone.net/jeboud/temp.htm There is some blue noticeable to the outside of the brighter stars towards the edge of the field due to the scope's coma, and a guest satellite <g>. My focus point was about 1/8 of the field from center. John Boudreau -- ----------------------------------------------------------------------------- Michael J Greger Intel Corporation mgreger@dashmail.net Intel Server Chipset Design Engineer http://www.geocities.com/mjgreger0 These are my opinions, not those of Intel! ----------------------------------------------------------------------------- |