Interesting! So maybe if a 90mm covers 5x7....a 165mm may, and I say 'may' cover 8x10??! ;-)
Like the 90mm was intended for 9x12cm but is mostly used on 4x5", so the 165mm was intended for 18x24cm and is often used on 8x10". The difference in coverage stated and needed is identical. A 120mm Angulon on 8x10" would look as "bad" as a 90mm on 5x7".
For the purpose of contact prints, a 165mm Angulon is more than adequate for 8x10". Maybe I should give mine a try on 24x30cm (9.5x12")?
Sadly I didn't have the 165mm(older version) and the 165mm I have here now which is the newer type just for sake of comparison. I will be able to pop this one on the 8x20 and get the maximum circle and see how much is useable though.
Actually since I wrote that last post I am now in possession of the two different types of 165mm Angulon, a Super in a Copal #3, a barrel Angulon and another in a Copal #3 so I'll see what I can garner from them.
Scanning at 600 dpi and displaying it full size on a screen is equivalent to a 6 to 8 times enlargement. Enough to take a 5x7" negative to 40x54", or a 4x5" to 32x40". If it looks acceptable from "normal screen distance", it will look even better on the wall!