Small Aperture LF lens

[jhotopf]

Recently got a Nikon 300mm F9 lens for 4x5 and 5x7, was apprehensive about how bright and easy it would be to focus. Bright enough here on the Szabad 5x7. Seems brighter than the 90mm F4.5. The image in real life is a lot brighter as the phone has underexposed this.

 

[martin henson]

I wonder why, I struggle with a f6.8 in lower light conditions, never mind a f9, must be the screen your using unless some one could enlighten me

 

[jhotopf]

I wonder why, I struggle with a f6.8 in lower light conditions, never mind a f9, must be the screen your using unless some one could enlighten me

Hi Martin,

It's an old screen dating from 1948 I think, maybe the fact that it's a long lens makes a difference? By the way love your youtube channel, particularly enjoyed your recent one on stand development.

Jonathan

 

[martin henson]

Ah never thought of that, thanks

 

[Stephen Batey]

f/6.8 makes me think of wide angle lenses. If so, this recent post may shed some light on the matter:

https://www.5x4.co.uk/threads/nikon-sw-75mm-f-4-5-wanted-or-similar.1676/#post-14497

Edit to add:
I know that the subject of not being able to see on a ground glass with a small aperture has been discussed quite a few times on another forum. Some have struggled with lenses that don't have any problem on my camera(s) so I tend to assume it's a screen problem.

 

[Ian Grant]

I have an f14 Ross EWA it's actually a Zeiss Protar design, it's 141mm and covers 10x8 and surprisingly is easy to focus.

In another thread I mentioned that slow very wide angle lenses and Fresnel screens can be an issue and can be better with a plain GG screen.

Ian