So it sounds as if your sharpness problems are occurring only with your 4x objective?leander wrote:For 4:1 I put a 4x microscope objective on my 200mm macro and open the lens all the way because if you don't you will get crazy vignetting as you said. I sometimes notice I don't get things as sharp as I like that is why I was asking about REAR curtain sync and Stackshot controller settings.
For 10:1 I move to a wood rig I made and put a 10x objective on the front of my 200mm macro though I have also used a bellows, again wide open f stop. No issues with sharpness as all things are pretty well locked down. Plus I push "go" for a stack and leave the room so I'm not the cause of any vibration.
My first thought would be that the 4x objective may have issues, but you did say "sometimes." If that's the case, the 4x objective must be OK.
It appears that at 10x, you switch to a higher level of anti-vibration discipline (leave the room, use a wood rig (presumably with camera and subject stage both mounted on the wood?) So let me ask the obvious question: Have you tried your stricter 10x protocol when using your 4x lens? I wouldn't be surprised if your issues go away. In my own work, I use the same anti-vibration cautions at 5x as at 100x.