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Michael Roberts
4-Apr-2010, 19:38
Okay, so ULF and odd-sized film holders are expensive--even used, vintage (very used) holders. Here is an experiment to make your (i.e., my) own. The catch is, I have zero woodworking skills and very minimal equipment (a 10-inch mitre saw, an 18-inch metal ruler, a pencil, and a bottle of contact cement).....plus access to a really well-stocked hardware store that conveniently has a good supply of craft wood....

This first attempt is for 7x11 holders:

I start with craft wood (basswood) in three sizes:
3/4 x 1/8 x 24"
1/2 x 1/16 x 24
3/4 x 1/16 x 24

(T-dimension for 7x11 holders is .25 inch.)

Here's the result of today's efforts:

Michael Roberts
4-Apr-2010, 19:43
One more valuable piece of equipment: a heavy-duty right angle ruler to keep the corners 90 degrees....

Material for plenum and darkslides is Garolite from McMaster-Carr 12x24 in 1/32 thickness...this can be scored with a utility knife several times, then snapped, and the edge sanded down (my honey loaned me her Dremel for sanding)....

Michael Roberts
4-Apr-2010, 19:52
I made four wooden sides first (for two DDS holders)--cut and glued the pieces together.
Then I cut one piece of Garolite to make a plenum and two darkslides.

Next to do:
-glue the two sides of each holder together with the plenum in the middle.
-fabricate the lighttraps (I bought some open-cell foam and felt fabric for this).
-paint the wood a flat black (or, possibly stain it, I'm still waffling on this, but leaning toward black to fill in any gaps in the joints...).

Oh, you might be wondering about the end flaps--there aren't any. I designed these holders to use the double-sided 3M tape (ATG) so I won't need film guides or a hinged end-flap....

SR95RACER
5-Apr-2010, 07:19
Great job Michael !Give it a nice coat of varnish before putting it together and you shall rule !

Michael Filler
5-Apr-2010, 08:09
I'd say AMAZING! An inspiration to all of us. It's back to the early days of photography, when one had to make almost everything. Good job!

thart2009
5-Apr-2010, 08:11
impressive & inspiring..

BradS
5-Apr-2010, 08:45
Yes. Amazing and inspiring. THANK YOU! for sharing these details.

Michael Roberts
7-Apr-2010, 06:34
Thanks very much for the kind words...I do hope this inspires some folks to try their hand at making holders to shoot more film--especially in odd and ULF sizes. I am figuring my cost for each 7x11 holder is no more than $20-25 in materials (versus $75-85 each for vintage holders and $250+ for new S&S holders). I'd love to have half a dozen or more holders each in 7x11 and 11x14, so, if possible, I'd rather spend the extra $$ on film.

The savings will be even more for 11x14 holders. I will work up a prototype 11x14 in the next few weeks. I expect the cost to be around $35 for materials (already have them on hand, in fact) versus $200+ for used holders (when you can find them) and $350-400 for new holders.

Here are a couple of more pictures...

-I did opt for flat black for these first two holders. Film holders absolutely, positively have to be light-tight, so I decided to be extra cautious with these first two experimental holders. If I can't make holders light-tight, then this whole effort will be a write-off...no matter how pretty they might o/w look.

-A couple of things I learned since the last post:

-the top and bottom pieces that make up the slot for the darkslide at the end of the holder need to have the edges facing the dark slide sanded down to make it easier for the dark slide to find the gap (next time I'll do this before assembly!)

-if you are going to paint the inside of the slot for the dark slide, do it before assembly.

I did some experimenting with light traps...this has been my biggest concern throughout the design stage...

-my original idea to use open-cell foam covered in black felt did not work--way too thick for the 1/16 opening

-I found a post on the f295.org cite where RayH in Oz uses self-adhesive Velcro material--just the soft side. I got some of this, but it is too thick, also (should work well for the 11x14 holders, though; Ray uses this with 3mm MDF material)

-I finally settled on just one layer of the black felt I had--it's 1/16 inch thick (I also tried doubling over part of it, and it was still too thick)

-alas, final testing is going to have be done with film, in the field, I think. I hope to get to that next week.

The good news is (a) I'm nearly done with my first two 7x11 prototypes, (b) the weight is incredibly low--only 10 oz (I'm hoping for 11x14 holders close to 20 oz!), and (c) I've learned a few things without completely buggering this up yet.

The first pic shows the painted holder (now with both sides glued together and the Garolite plenum sandwiched in between) with felt light-trap glued in place; the second shows the cover and rib-lock added (but not yet screwed into place).

Bill Kumpf
7-Apr-2010, 12:44
Michael,

Consider posting this on the LF Home Page. It would be an good addition.

Michael Roberts
7-Apr-2010, 14:36
Cool. Thanks Bill. I'd be happy to write up an article with better pics since I do plan to make more (and, possibly some prettier ones) IF these work. The acid test is still yet to come, though....

I saw on the f295.org site where someone else also observed it is hard to find DIY filmholder info on the web. There's a lot more info available about camera-building, bellows construction, etc.--I guess because most camera- and bellows-builders shoot 4x5, 5x7, or 8x10 where there are holders available at reasonable prices.

seabird
7-Apr-2010, 14:51
Michael,

Congratulations. I really hope the holders work well for you.




-alas, final testing is going to have be done with film, in the field, I think. I hope to get to that next week.


I'm sure I dont need to tell you, but remember that you can perform initial tests for light-tightness using paper rather than film - should be a lot cheaper and you wont have to sacrifice any of that expensive ULF film.

Best

David Karp
7-Apr-2010, 15:43
I agree. This would be a fantastic article for the home page.

svarzaru
8-Apr-2010, 06:53
Keep us posted! It looks very interesting.

Michael Roberts
9-Apr-2010, 09:57
Thanks Sorin. I will. I'm out of town this weekend, but will finish up these first two holders and test them out next week and post results. If these work out, I'll post all the specs and then do the same for 11x14.

Michael Roberts
19-Apr-2010, 07:04
Not a lot of progress this past week, but solved a huge problem last night--the lighttrap for the dark slide. I'd been having a problem with the dark slide bowing in the middle, producing a small, but obvious light leak in the center of the opening. I considered various alternatives--

1. increasing the thickness of the felt in various ways,
2. using a more rigid covering material (e.g., some type of metal),
3. cutting away some of the felt for a narrower strip.

Option 1 did not help; same problem. Option 2 did not seem to work, either (doubling the thickness of the wood overlay). Tried option 3 and, voila, no light leak.

Turns out placing the felt right up to the edge of the groove for the darkslide was pinching the dark slide, causing upward pressure in the middle (the bowing I was getting).

I have to confess I finally brought my spare brain in to work on this--it's great having a wife with an engineering degree.:)

The picture is pretty ugly, as I was cutting and tearing away the felt that I had already glued in place. On the next holder, I'll cut the felt the appropriate width before gluing it down.

I also discovered I need a smaller rib lock than anticipated. Most modern holders use 3/16 inch. My vintage Kodak 7x11 holder (and, more importantly, the groove in the spring back) is 1/8. So back to the hardware store today....

Michael Roberts
26-May-2010, 08:03
Took a break from this project to work on the 7x11 back for my camera:

http://www.largeformatphotography.info/forum/showthread.php?t=62789

Here are a couple of updates showing the 2d try with the felt and the cover (with rib) in place.

Last step (other than putting in the double-sided tape) is to decide whether to use pull-tabs or wooden handles on the dark slides. I have been considering pull-tabs b/c it will allow me to use all of one 12x24 sheet of Garolite with no waste, but handles will help block direct light that might o/w find its way inside the holder.....

btw, the black strips under the holder in pic #1 are more felt strips I cut for additional holders.

This holder slides in/out of the spring back and the rib lock drops into place nicely; so far, so good....

J Ney
26-May-2010, 08:30
This is an evil post that gives hope to folks in the 4x5 / 8x10 world that larger formats can be obtained without the ridiculous cost of film holders. Assuming your 11x14 holders go well, it would nearly make it affordable.

All kidding aside, this is amazing. Great job!!!

Michael Roberts
26-May-2010, 08:56
Yeah, my fantasy is a 20x24 holder, using the double-sided tape, and placing six 8x10 sheets of x-ray film side by side--6 sheets total at 50 cents each--$3 for 20x24. Talk about ULF on a budget!:)

Barry Young
1-Jun-2010, 10:48
Okay, so ULF and odd-sized film holders are expensive--even used, vintage (very used) holders. Here is an experiment to make your (i.e., my) own. The catch is, I have zero woodworking skills and very minimal equipment (a 10-inch mitre saw, an 18-inch metal ruler, a pencil, and a bottle of contact cement).....plus access to a really well-stocked hardware store that conveniently has a good supply of craft wood....

This first attempt is for 7x11 holders:

I start with craft wood (basswood) in three sizes:
3/4 x 1/8 x 24"
1/2 x 1/16 x 24
3/4 x 1/16 x 24

(T-dimension for 7x11 holders is .25 inch.)

Here's the result of today's efforts:

Hi Michael:

Just curious how you are going to cut the grooves for the darkslides with a chop saw?

Barry Young

Michael Roberts
2-Jun-2010, 21:03
Hi Barry,
I'm not cutting grooves; instead, I am sandwiching the 1/2 inch wide wood between the two 3/4 inch wide pieces. This leaves a 1/4 inch groove all the way around the three closed sides. See the first set of pictures on page 1 of this thread.

By selecting the right dimensions of pre-cut wood pieces, there is no need to plane down the wood or rip it; just chop the lengths to the needed sizes.

BTW, I'm still working on getting the baffle/light trap right. Eric Larsen has given me a lead on finger springs that I am following up.

barryjyoung
4-Jun-2010, 07:05
Hi Michael:

OK, thank you. Good luck with your project.

Barry Young

Michael Roberts
12-Oct-2010, 10:01
It's been a while since I've added to this post. I did some more experimenting with the light baffle (where the dark slide slides in /out). Thanks to Erik Larsen, I found some finger springs at Omega Shielding that I'm trying out. Here is the link:

http://www.omegashielding.com/099-720-NT.php

My first try was to glue blackout cloth, painted flat black on one side, down on both sides of the springs. That still let some light through, so I then pried up the side of the fabric closest to the film, following a suggestion by Erik to glue the fabric down only on the edge closest to the insertion point. This seems to work well, and the opening appears to be light-tight when the dark slide is in and out.

Next step is to complete the assembly and try it out!

Steve Salmons
13-Oct-2010, 04:55
I have just picked up on this thread rather late. You may have considered this already but I have used black velvet ribbon (which can purchased in a wide variety of widths), to renew light traps on cameras. David Odess has expressed a preference for this when restoring light traps on Hasselblad backs on his website. Worth a try if your experiments with felt are proving troublesome

Erik Larsen
13-Oct-2010, 06:05
Hi Michael, keep up the good work. If you find you are getting leaks still, Steve's suggestion is a good one. I have used black moleskin that is similar to velvet but is adhesive backed. It is used for sealing auto windows. You can get it from 1/4 inch to 2 inches wide I believe. Good luck with the project.
regards
erik

Michael Roberts
13-Oct-2010, 06:07
Thanks Steve. Ribbon suggests to me a velvet/nylon combination. I'll look for David's website to see if he provides more details and will check my local fabric stores.

Michael Roberts
25-Aug-2019, 09:43
Given Paul's recent thread on his 14x17 film holder project (https://www.largeformatphotography.info/forum/showthread.php?143039-14x17-film-holder-build-question , I went searching for this old thread. Finally found it (apparently search terms are case-sensitive). It was one of the old posts where the attached photos were lost in a server migration. So I searched my hard drives and found the old photos. Since the mods now allow perpetual editing, I was able to restore the old attached photos to the appropriate posts (more or less).

Believe it or not, I am still working on these holders. Or to be more accurate, I put them away for about eight years before resuming work on them this past year (one of many projects I quit my day job to have time to get back to a couple of years ago).

I think I solved the baffle problem (with Erik Larsen's help). I'm still working on getting the 3M adhesive tape to work.

The last two times I have tested my first prototype in the field (once in February of this year and again in June of this year), the film fell out of the holder and into the camera bellows, i.e., the adhesive did not hold the film. Right now, my working hypothesis is I may have a problem with altitude changes. I live at 8,600' and extended time in the holder plus changing several thousand feet of altitude may be causing air between the adhesive and the film to expand/contract and loosen the film. If so, I need to do a better job of laying the tape down on the plenum with no wrinkles or make sure I press the film down in the morning before shooting or carry a changing back with me so I can check and press the film down when needed, as least during the experimental phase.

Still hoping to perfect these!

Michael Roberts
25-Aug-2019, 10:50
There is also a discussion of adhesive film holders in this thread: https://www.largeformatphotography.info/forum/showthread.php?88122-Adhesive-holders

Still working on applying all of Drew Wiley's suggestions and experience to this project....