Lens adjustment ...

[afaceinthecrowd]

I remember coming across instructions somewhere out there in cyberspace to adjust a lens for infinity focus. I'm thinking of folders and TLR's.

It seems to me that the procedure was went something like this:

1) download and print target - hang on wall
2) set camera on tripod at 20-25 feet from target
3) place ground glass on film plane
4) check focus with loupe
5) adjust infinity stop on lens if need be

Does this sound familiar to anyone? I've googled the heck out of it and checked all of my bookmarks but I can't find the URL again. I think I can figure out the process but I need the target. If I recall correctly it was a US govt. site ... NASA??

Any help would be appreciated.

TIA

dan 😀

 

[afaceinthecrowd]

Our local drag stip is only an 1/8 of a mile 🙂

The chart I was looking for is called USAF 1951 lens chart ... I think I have found it but could still use some pointers on setting up the lens on these old beasts. I have a Beautyflex TLR with lenses that link using a gear on each lens. I know I didn't quite get it back together exactly as it was disassembled ... assuming that it was right to start with 😀

dan

 

[afaceinthecrowd]

Gotcha 😀 I'll set up as far away as I can.

Thanks as always!

dan

 

[ZeissFan]

No, the better and more accurate way is to collimate using an SLR. I've used the loupe + ground glass method, but it's not nearly as precise as using an SLR.

Instructions here:
http://host.fptoday.com/melek/zeiss/repair/collimate/collimate.html

 

[afaceinthecrowd]

Thanks for the link! I guess that would work with any type of camera ...

Maybe I'll try both and see which work better 😀

dan

 

[doubs43]

Gotcha 😀 I'll set up as far away as I can. dan

Dan, I use a tree line about 3/8 of a mile away and a groundglass/10x loupe. It's worked pretty well for me. Winter trees that have lost their leaves are great as the bare branches make wonderful focusing objects.

Walker

 

[mad_boy]

Why not do it at night aiming for the moon or the stars?
- These are as infinitely away as can be.
- Focus on starts should be easy to see.

mad_boy