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I use the SMC-M 100mm F4 l;ens with a set of vivitar auto-extension tubes
Tube set is 12mm, 20mm, 36mm.
"Auto" means there is apature cooupling so you can focus wide open, but stop lens down when shooting.
No AE contacts on my set, fully manual.
They work just fine, after all, they are just hollow
, not like a TC where added glass reduces image quality.
You really need to use a tripod, because with the full 68mm of extension, plus the 50mm of extension built into the 100mm F4 you are working at greater than 1:1 and depth of field is measured in microns! (not quite but you get the idea)
With this arrangement it is best to also have a focusing rack and pinion, between camera and tripod, so the camera body can be moved aslo to assist in focusing. it is easier to control than moving the tripod.
you are OK on vertical without this as you can always use the tripod center post