Hey y'all,

I'm travelling to NM this summer for 3 months and bringing my 4x5. I'll be doing lots of backpacking so I'm looking to save weight and make my kit as rugged as possible.
I have a question about groundglasses. Does the thickness matter for accurate focus? I'm thinking of making a spare out of some styrene in case I break my GG in travel or a fall. They're not quite the same thickness. It seems to make sense to me that if the lens-side of the GG stays the same the thickness shouldn't matter, i.e. how far back the user-side of the GG extends. There are obviously other considerations such as sharpess, brightness, etc. All I'm wondering about at the moment is whether or not the focus would be affected by a thinner GG. I'm fairly new to LF so explain like I'm stupid haha.

Benno