Macro Rail Mods

[Cap'n Bill]

My ebay focus rail is remarkably well made for the price but I found it difficult to read the scales with any accuracy better than 1mm and the adjustment is coarse at about 29mm/rev of the rather small adjustment wheel so I made some modifications.

Mod 1. I fitted a larger adjustment wheel of about twice the diameter. this knob also has a pointer on it so it's easier to judge how far it is turned for each step.

Mod 2 A nice clear pointer directly over the rack scale so movement can be read reasonably accurately

Mod 3. A digital gauge was fitted to the side to measure actual movement of the rack. Digital readout to 0.001mm. Using this limits travel to 20mm but that is enough fo small subjects.

It looks as though I should reliable be able to get focus stack steps to a good degree of accuracy with these modifications.

 

[THIRTYFIVEMILL]

Interesting Bill. Would be great to see a picture of that one. I might consider doing something similar myself.

 

[Cap'n Bill]

Your wish is my command

Actually I was struggling with upload but have sorted procedure now I think

 

[THIRTYFIVEMILL]

Your wish is my command

Actually I was struggling with upload but have sorted procedure now I think

Great stuff, many thanks. My brain rarely understands much unless I can see it!

 

[AJQS]

You need to get that DRO square or you won't be reading any more accurately at all.

 

[Cap'n Bill]

It's adjustable. Just noticed it wasn't still square when processing pics and must have nudged it when photographing, couldn't be bothered to redo.

At present the DRO pinch screw clamps onto round 4mm support bar and I think I will mill a flat on the bar to reduce the risk of twisting. The problem and error is very minor though.