>>3482636>By stopping down, you're just increasing the depth of field enough to where you can get shit into any focus at all.You essentially get so "small" relative to the length of extension tube that the aperture opening starts to become a pinhole f-stop where, "circles of confusion" come into play and everything gets fuzzy. I get that all the time with my gear. There's really no trade off when you want sharpness, unfortunately. A lot of that has to do with how sharp the lens is in the first place, but only to a certain point. Basically, use a more powerful lens if you are getting past x amount of extension, instead of using anything past that amount of extension.
One of these days I'll get some paper tubes and make a huge telescoping extension tube to see exactly where lenses start to crap out at. As example, with this image there's 171mm of extension with a reversed 6.5mm lens. It far overshoots the mark for fuzzy, it gets worse the further I push it, but f/8 is the clearest f-stop it seems. At least with it I'll be able to put it on the bellows and find out where its acceptable fuzziness max extension is. The subject is a ruler and the white line is a mm mark.
>>3482645What rig is that?
