abruzzi
Member
I've been shooting 4x5 for a few years and have just started the process of adding 8x10 to my arsenal. While getting setup, I've developed a theory--
first, we all know that on a linear dimension, 8x10 is twice 4x5, i.e. 4" doubles to 8" and 5" doubles to 10". But in photography the only one dimensional action I can think of is focusing, so I need a 300 instead of a 150, and I need a minimum of 500mm of bellows instead of 250mm of bellows.
when we add a second dimension, things start to make sense. In two dimensions, 8x10 is 4 times the area of 4x5. Film is essentially two dimensional (the thickness being apparently irrelevant to this discussion). So 8x10 film is 4 times the cost of the same film in 4x5. 50 sheets of fomapan 100 in 4x5 is about 50 dollars, or a dollar a sheet. 50 sheets in 8x10 is about $200 or $4 a sheet.
When we add a third dimension, we now have an 8 fold increase. So a simple beginner quality (i.e. functional but very used) 150mm lens is about $100-$150. In similar condition a 300mm lens is $600-$1000 (ok, its not quite 8x, but close). I can get good condition used relatively modern 4x5 film holder for $10-$15, but an 8x10 film holder is $80-$120. (in this case the third dimension of the film holder seems to be significant.)
But what about the 4th dimensions? Well, if we assume that time is the 4th dimension, then actually shooting 8x10 should be 16 times more difficult and time consuming. Having just shot a couple of test sheets, I'm thinking that may actually be the case.

first, we all know that on a linear dimension, 8x10 is twice 4x5, i.e. 4" doubles to 8" and 5" doubles to 10". But in photography the only one dimensional action I can think of is focusing, so I need a 300 instead of a 150, and I need a minimum of 500mm of bellows instead of 250mm of bellows.
when we add a second dimension, things start to make sense. In two dimensions, 8x10 is 4 times the area of 4x5. Film is essentially two dimensional (the thickness being apparently irrelevant to this discussion). So 8x10 film is 4 times the cost of the same film in 4x5. 50 sheets of fomapan 100 in 4x5 is about 50 dollars, or a dollar a sheet. 50 sheets in 8x10 is about $200 or $4 a sheet.
When we add a third dimension, we now have an 8 fold increase. So a simple beginner quality (i.e. functional but very used) 150mm lens is about $100-$150. In similar condition a 300mm lens is $600-$1000 (ok, its not quite 8x, but close). I can get good condition used relatively modern 4x5 film holder for $10-$15, but an 8x10 film holder is $80-$120. (in this case the third dimension of the film holder seems to be significant.)
But what about the 4th dimensions? Well, if we assume that time is the 4th dimension, then actually shooting 8x10 should be 16 times more difficult and time consuming. Having just shot a couple of test sheets, I'm thinking that may actually be the case.
