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Byron Davies

M-52, NGC-7635, SH2-157, SH2-158, SH2-159, SH2-161, NGC-7510

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Posts Made By: Donald Mathisen

November 18, 2010 04:19 PM Forum: AstroMart FAQ

Posting pictures to Ads

Posted By Donald Mathisen

I am having problems loading pictures to the ads i am placing unless I reduce the size to ~250 Kb. I am uploading as jpg files and have had to convert to 16 bit B/W photos to reduce the size sufficiently.

Can anyone help?

Don Mathisen

November 7, 2003 04:53 PM Forum: Equipment Talk

Monocentric eyepeices

Posted By Donald Mathisen

Hi Inge,

In considering the TMB monos keep in mind that they have a limited AFOV. I bought the 4 mm mono for my TMB 105/650. While the eyepiece was quite sharp and contrasty on axis I found the narrow field of view combined with the field cuvature, in this fast scope, to restrict the useable field to ~25 degrees. This proved to be two much of an hassle with the Giro mount I use - too much nudging to keep things centered and focused. In all, I found my 4 mm UO Ortho to be better suited to my particular setup. I might feel differently if I had a GEM.

Don