Adjusting infinity on a SMC Pentax-A zoom lens?

blacknosugar · 10-21-2018, 03:05 PM

Does anyone know how to do this?
Infinity was badly short at 200mm on this 80-200mm lens.
I've performed some lens fungus exorcisms before with some success on earlier prime lenses but I can't figure out how this one plastic-y one is put together.

**TwoUptons** · 12-01-2018, 10:16 AM

I did a 45-125 with the same issue, though that’s an older lens.

On that one, there were adjusting screws underneath the focusing rubber.

Basically, you loosen the adjusting screws, focus at infinity, and then tighten it down again. There was some iteration, but it worked pretty well.

-Eric

10-21-2018, 03:05 PM	#1
blacknosugar Forum Member Join Date: Dec 2011 Posts: 58	Adjusting infinity on a SMC Pentax-A zoom lens? Does anyone know how to do this? Infinity was badly short at 200mm on this 80-200mm lens. I've performed some lens fungus exorcisms before with some success on earlier prime lenses but I can't figure out how this one plastic-y one is put together.

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12-01-2018, 10:16 AM	#2
TwoUptons Loyal Site Supporter Join Date: Nov 2015 Photos: Albums Posts: 4,224	I did a 45-125 with the same issue, though that’s an older lens. On that one, there were adjusting screws underneath the focusing rubber. Basically, you loosen the adjusting screws, focus at infinity, and then tighten it down again. There was some iteration, but it worked pretty well. -Eric