Quote Originally Posted by ic-racer View Post
I'm not sure what you mean by crop factors or APS-C but the diagonal of 6x9cm is around 105mm and the diagonal of 4x5" is around 150mm. A 180mm on 6x9cm camera is slightly long. In general, lenses that cover 4x5" format will work fine on your Shen-Hao TFC69-A.
"crop factor"? Cropping is done under the enlarger.