Quick and dirty electronic focus for any DSLR lens

[powerlord]

I've got a bunch of manual vintage prime DSLR lenses, plus a new Samyang 135mm f2 ordered.

I find them quite tricky to get the focus spot on, especially with the wider ones. I use bahtinovs that I've printed specifically for each lens, but you only get tiny wee crosses with the wider ones.

And with 10x live view on the camera, trying to see if it's spot on which also moving around as you are adjusting focus is really tricky.

Anyway, as I upgraded to ZWO EAF I have a few of the basic 60 quid skywatcher focusers lying around. Here's a video showing how to rig up a basic way to let you use that to focus any DSLR lens.

all you need is a few of these sort of things:

https://www.ebay.co.uk/itm/392914563455?hash=item5b7b88717f:g:GNAAAOSwEYpc5khK

a strip of rubber and an elastic band. One of these and there:

https://www.ebay.co.uk/itm/223461492884  - a 300mm works well

https://www.ebay.co.uk/itm/223280281197   - 6mm

and a few camera UNC bolts.

works a treat.

 

[powerlord]

here it is fitted to the new Samyang 135mm i just got in the post. the rubber on the focuser has enough grip, so no need for rubber strip with that. as only tiny wee amounts needed to get that in focus it's gonna make it a hell of a lot easier to get it pin sharp.