goerz 45 cm artar

[rick_abraham1]

I have been offered a goerz red dot 45 cm artar for my 8 x 10. I

have found quite a lot of info about the 19 cm artar in the threads

but little about this lens (assuming it is not the same). Does

anyone have any comments on the quality and coverage of this lens.

Many thanks.

[robert_a._zeichner1]

The 17-3/4" (450mm) Artar to which you refer has a 46 degree angle of coverage and will, at infinity cover diagaonals of 15.1". This is ample to cover an 8x10 negative as that diagonal is 12.8". Other than that, its optimum aperture is said to be f22 and if it is a barrel mount lens was most likely optimized for 3:1. Is this a barrel mount or is in in a shutter? What shutter? If in a shutter, is it front mounted?

[rick_abraham1]

It is front mounted in an Ilex no 4.

Ta

[robert_a._zeichner1]

If it's front mounted, there is a small chance that the maximum diameter of the shutter may be a bit smaller than that needed to permit the lens to reach its full coverage. Essentially, it could vignette. I've never had that specific lens, so you might want to experiment. If you have cut corners on your gg, you could eyeball it. Do so at infinity with the lens aperture (not the shutter's) set to a real world setting. Have you checked Steve Grimes site? He has a chart that lists common lenses that could be front mounted and in what size shutter this can be accomplished.