Don't know if this is the right forum but bought a very cheap s/h [but appears unused] Vivitar 100-200mmf/4 zoom with Pentax screw [M42 thread] mount but it will not quite reach infinity focus whilst against the infinity stop at any zoom setting. Due to its low cost I'm prepared to tinker but can't see any obvious screws to remove or how to shift the front focusing element perhaps 0.5mm 'inwards' to reach infinity. Any advise
Thanks - desected lens rear end and found the problem - the rear lens element was slightly unscrewed and so rectified but now I had to re-assemble the four interlocking rings and levers - took three goes then I spied a flea-sized spring and sub-millimeter ball bearing on the table! Where did that come from? Took some time to realise it was part of the click-stop mechanism for the lens f/4-f/22 preset apertures. Still got a bit of a problem with the click-stops but lens focuses perfectly at infinity and down to <1m plus 100-200mm zoom and it does a fair job in close-up on our apple blossom with bee
Previous
Index
Next
Threaded
Edit
Reply
Quote
