Why no 180mm's for 8x10?

[Lachlan 717]

I need to make it clear what I was responding to. In the Opening Post they pointed out that a 240mm covers 8x10, but that his 180mm doesn't. I don't believe that person was accounting for the differences in lens design that can yield considerable differences in the size of the image circle. So I tried to explain that.

And it was rebutted with examples of cheap (relatively) lenses of circa 180mm or less lenses.

Unfortunately, while your contention can be a factor, it is not a singular, all-compelling contention.

[ethics_gradient]

I have a Yamasaki Congo 18cm f/4.5 barrel lens that covers 8x10 at infinity well enough for wet plate collodion; have not looked at the corners closely, but I'm happy enough with it. Considering I paid under AU$80 for it (thanks to some easily addressed fungus) only planning to use it on 4x5, I'm pretty pleased.