mounting petzval projection lens

[gflanslo]

I've just received a new (old) petzval projection lens with flange but I'm not sure how to mount it on a board. I do not have access to tools to drill my own hole so I need another way to hack this onto a board. What have people been doing to mount these lenses? I'm going to be putting this on a cambo 4x5

[Gene McCluney]

If you are going to want to mount this on a metal or wood board, you will have to use some sort of tools to carve out a hole. If you want a "temporary" mounting you can just mount to stiff cardboard, which could be cut with a utility knife (very cheap at hardware store). There is no way around having to use "tools" to cut your hole in a permanent board, unless you can find a lensboard with a hole already cut. You could also look in your telephone book yellow pages for a listing for a woodworking and/or metalworking shop. They might do the work for you for a modest cost. This is not "high tech" and any cabinet maker shop (for wood) or metalworking shop (for metal) could do this for you, particularly if you mark out on the blank lensboard what you want. Also, if you are going to use a thin wood lensboard (and you CAN use wood lensboards on cameras designed for metal boards, they just have to be thin), you COULD just get a hole-saw attachment for a common electric drill. The drill and the saw blade are not expensive.

[BarryS]

For experimental lenses, I've been making temporary boards out of three-layer laminates of black core mat board. I cut out a bunch of blanks using my mat cutter, although all you need is a straight edge and a sharp utility knife. Then I trace or use a compass to draw the size of the hole I need on three boards and use an Exacto knife to cut out the holes. Finally, I use a thin coat of wood glue to laminate the three boards together and mount the lens with screws, tape, or whatever is appropriate. A three layer laminate is very dimensionally stable and I've used this technique to mount a fairly heavy lens with no problems.

For more permanent solutions, I bought some baltic birch plywood from the local hobby store and I will be cutting this down with a small jig saw or on a cheap small table saw from Harbor Freight. Then I'll use a small Exacto keyhole saw and a file to cut and finish the lens holes. I may get fancy and glue some exotic wood veneers to my birch boards if I really get motivated.

[Brian Bullen]

Hey Greg, both Barry and Gene methods will work well. Usually for smaller(4x5) lenses I cut a piece of cardboard from my kids diaper box(I have plenty of those around). Sometimes tape is added to secure everything in place and off I go. I haven't had any light leaks. If the lens is a keeper then I make something that will last longer and is strong enough to keep me from worrying.
http://bp1.blogger.com/_DTvpw4AOnVQ/RzkWiwqjueI/AAAAAAAAAI0/sVB_DnvltrI/s1600-h/hjtb.jpg
Even though the board is wrinkled, once it was on the camera it was tight enough to be light tight.

[gflanslo]

thanks for your replies everyone. You have got me started on some ways to get this going. I think I'll start out with a temporary quick solution and if I really like the lens I purchase an undrilled lensboard and bring it to a machine shop.

I'm in the process of building a useful set of tools for a large format system. My goal is to be able to maintain my system and experiment with some DIY projects. I currently have a lens wrench and the basics: drill, screw driver, ect. I don't own and specialty saws but do have hobby/utility knives. Any recommendations for tools that you have found especially helpful?

[Brook Martin]

I have used a SK Grimes lens wrench to cut lens sized holes in 1/4 soft plywood, sort of like drawing a circle with a compass, but with more force. Not recommonded, but doable.

A cheap table saw will prove its worth over time, but do be careful with them. A small compressor and a brad nailer are super handy if you are building adapter boards, packard shutter housings, ect.

A roll of black gaff tape is an absolute must

[Pat Hilander]

Yep, gaffers tape always comes in handy! I also have a spanner wrench and a set of teeny tiny screwdrivers that get used a lot.


For cutting holes in metal boards, I trace the outline of the flange on the board then use a drill with a small bit and drill holes around the circle about 1/8 inch apart. Then I use a cutting wheel on a Dremel to cut between the holes. Dremel's and a nice set of attachments always seem to come in handy too!

[gflanslo]

14037

Thanks for everyones help. Here are the two boards I put together using a black foam type board. It turned about to be a really nice fit in terms of width.

[Pat Hilander]

14037

Thanks for everyones help. Here are the two boards I put together using a black foam type board. It turned about to be a really nice fit in terms of width.


NIce job!

Show us some pics from the lenses after ypou try them out!

[gflanslo]

I plan on using the lenses this weekend so I'll post what happens. I hope my homemade wrist shutter works well!!! anyone have any tip or hints?