14x17 build, with filmholders and tripod

[radii]

Hello,

I wanted to share my latest build, which is a foldable 14x17 camera, with a 11x14 reducing back.
Along with it, I also made 4 filmholders per format, and a tripod.

All wood is walnut and the shiny bits are aluminium. The bellows are made out of the Thorlabs BK5 fabric with paper stiffeners, phosphor bronze for the leaf springs and light trap in the filmholders, and there is a carbon fiber rod in the bellows support.
Linear bearings and a lead screw move the front standard for fine focusing and semi-hidden linear bearings allow rough focusing with the rear standard.
Plenty of neodymium magnets hold various (re)movable parts in place.
The dark slides and septums are Garolite.

Total bellows draw is ~42" and it can focus a 355mm lens down to infinity without the bed appearing in the picture.

The camera weights about 19 lbs. and the tripod 10 lbs. Both seem sturdy. At this size, it's amazing to see the laws of mechanical leverage in action ;-)
The film holders weight 3 lbs 6 oz and 2 lbs 7 oz respectively.


It took me way too many hours to build it, many things didn't work out as planned (especially the folding mechanism and the sagging bellows) but all in all, I'm happy with it.

I still have to make bags for all of it and of course, take a picture with it.


Let me know what you think.


Thanks

JP

(pardon the too many pictures in too many replies)

https://s20.postimg.cc/miijsn0jx/mutti_14x17_frm_-1.jpg (https://postimg.cc/image/ozuazwkg9/)

https://s20.postimg.cc/ibxpdb0y5/mutti_14x17_frm_-3.jpg (https://postimg.cc/image/iop3jhj7t/)

https://s20.postimg.cc/o1dxxm74d/mutti_14x17_frm_-4.jpg (https://postimg.cc/image/7dmfv4ccp/)

https://s20.postimg.cc/alqx85yml/mutti_14x17_frm_-5.jpg (https://postimg.cc/image/kj1y18689/)

[radii]

https://s20.postimg.cc/wz398poy5/mutti_14x17_frm_-6.jpg (https://postimg.cc/image/juxow0ww9/)

https://s20.postimg.cc/74tgixoy5/mutti_14x17_frm_-7.jpg (https://postimg.cc/image/wnlsvy8i1/)

https://s20.postimg.cc/plnv9r4wd/mutti_14x17_frm_-8.jpg (https://postimg.cc/image/4c08ywoll/)

https://s20.postimg.cc/cis8qheod/mutti_14x17_frm_-9.jpg (https://postimg.cc/image/qcglfj79l/)

[radii]

https://s20.postimg.cc/i88haskul/mutti_14x17_frm_-10.jpg (https://postimg.cc/image/yj8l73xc9/)

https://s20.postimg.cc/ghpg9b3bh/mutti_14x17_frm_-11.jpg (https://postimg.cc/image/7molyseix/)

https://s20.postimg.cc/dc4uj3kp9/mutti_14x17_frm_-12.jpg (https://postimg.cc/image/5w5kxawzt/)

https://s20.postimg.cc/uf7mem1e5/mutti_14x17_frm_-14.jpg (https://postimg.cc/image/95k03rl3d/)

[radii]

https://s20.postimg.cc/a944fq5ql/mutti_14x17_frm_-15.jpg (https://postimg.cc/image/c0x3amp3d/)

https://s20.postimg.cc/uunhldcp9/mutti_14x17_frm_-16.jpg (https://postimg.cc/image/3wtkjms21/)

https://s20.postimg.cc/9z17a4gi5/mutti_14x17_frm_-17.jpg (https://postimg.cc/image/62nve4vih/)

https://s20.postimg.cc/ukfz20y31/mutti_14x17_frm_-18.jpg (https://postimg.cc/image/djx2tcl1l/)

[radii]

https://s20.postimg.cc/vo03dziq5/mutti_14x17_frm_-19.jpg (https://postimg.cc/image/tjfqcwh3d/)

https://s20.postimg.cc/6j930kj9p/mutti_14x17_frm_-20.jpg (https://postimg.cc/image/41xbtazd5/)

https://s20.postimg.cc/9em67fn9p/mutti_14x17_frm_-21.jpg (https://postimg.cc/image/bj6j8iow9/)

https://s20.postimg.cc/56rdyolu5/mutti_14x17_frm_-22.jpg (https://postimg.cc/image/9sni717d5/)

[Erik Larsen]

I'm very impressed, it looks fantastic!

[bob carnie]

Absolutely Stunning- I wish that I had your talent in making things , now you need to make pictures with the camera.

[Steven Tribe]

A little bit too much detailing for my taste, but the workmanship is impressive.

What would be more fun in this section is information/photos about the production of metal parts, woodwork and fasteners.
What kind of walnut?

[DrTang]

*jaw on ground*

[jb7]

Beautifully done...

[radii]

Absolutely Stunning- I wish that I had your talent in making things , now you need to make pictures with the camera.

From your lips to god's ears !!

[radii]

A little bit too much detailing for my taste, but the workmanship is impressive.

What would be more fun in this section is information/photos about the production of metal parts, woodwork and fasteners.
What kind of walnut?

I took no pictures during the making of it.

It was all drawn in 3D Rhino first and then milled on a 3 axis CNC router. Some table saw cutting, but not much ... and some laser rastering of letters.

The walnut (from the local lumberyard) is most probably plain old American.

[David Lobato]

You deserve all the glory with that beautiful camera.

[Dave Wooten]

Beautiful!

[Christopher Barrett]

Skills. Seriously.

[John Layton]

Stunning...Awsome...Inspired...I am basically speechless!

[Michael Jones]

Wow; amazing!

[Jim Fitzgerald]

Beautiful camera. Light weight, stunningly beautiful along with the tripod. What is not to like. Those 3D and CNC machines are awesome.

[radii]

Many thanks to all that like it and for the compliments !
And thanks to the ones that don't as well ;-)

[radii]

Beautiful camera. Light weight, stunningly beautiful along with the tripod. What is not to like. Those 3D and CNC machines are awesome.

When picking it up, 19 lbs does not seem light to me at all. I could have done with less aluminium maybe, but this was never going to be a featherweight-just-pick-me-up-and-go kinda camera anyways ...

[dsphotog]

A chick magnet camera !
Magnificent!

[B.S.Kumar]

This is magnificent!

Kumar

[Fr. Mark]

That's beautiful! Please tell us the source for the bellows material. I have a 100 y.o. 8x10 that needs a bellows.

[radii]

That's beautiful! Please tell us the source for the bellows material. I have a 100 y.o. 8x10 that needs a bellows.

It's the blackout material from Thorlabs

https://www.thorlabs.com/thorproduct.cfm?partnumber=BK5

There might be a better material for it out there, but I haven't been able to find it.
Bag bellows for organs are made with rubberized cloths for example.

The stiffeners in between the 2 layers were cut from 0.015" thick paper stock.

[Peter De Smidt]

All of the material for instrument repair that I've seen has been too thick. Great job on your build!

[Jim Fitzgerald]

When picking it up, 19 lbs does not seem light to me at all. I could have done with less aluminium maybe, but this was never going to be a featherweight-just-pick-me-up-and-go kinda camera anyways ...

I've built three 14x17's and the lightest is 26lbs. So 19lbs is awesome! Just right I feel. Holders are not eases bravo on them as well as that is the expensive part of 14x17.

[Rick Rycroft]

Fantastic work!

[c.d.ewen]

I wish....I wish....I wish....

Congrats!

Charley

[David Karp]

Beautiful!

[Daniel Strasshofer]

Amazing! Best appearance of all modern wooden cameras I`ve seen in the past years!

[Barry Kirsten]

Congratulations, radii. Your workmanship is superb; I'm in awe!

[jp]

Very beautiful!

[Fr. Mark]

Thanks for the bellows link. That's tremendous!
Why two layers? Also, what did you use for adhesives?

[Barry Kirsten]

You made a beautiful job of the bellows. May I ask, which/whose instructions did you follow? I built a 5x7 bellows recently that was supposed to come out square, but depending on how the fold sequence is started, either the large end or the small end comes out rectangular.

[radii]

Thanks for the bellows link. That's tremendous!
Why two layers? Also, what did you use for adhesives?

One layer only wouldn't be light proof enough, and the two layers allow good adhesion/sandwiching of the ribs.
I used 3m 465 transfer tape for adhesive. Super 77 spraymount works as well, but is trickier to apply evenly and leaves a rougher surfaces telegraphing through the fabric.

[radii]

You made a beautiful job of the bellows. May I ask, which/whose instructions did you follow? I built a 5x7 bellows recently that was supposed to come out square, but depending on how the fold sequence is started, either the large end or the small end comes out rectangular.

Thanks, but I have to disagree. They might fold up nicely and look decent, but the sagging at any extension makes me seriously doubt my approach.
The 5x7 and 8x10 bellows I've made before didn't have that problem, so it must be the weight and size that's the culprit.
The Thorlabs fabric, being only 0.005" thick, is probably just too flexible to provide enough stiffness for a bellow of that size. I have however not been able to source a material that is comparably flexible, light proof and on the thin side.

I can't remember the original link for the instructions that I used to calculate my bellows, but there's still some trial and error involved in it for me. I first plot out a paper template of the first row of ribs, knife it out, tape it together to form a very low pyramid and fold it up to see what I get. It's usually off from what I anticipated and then make the necessary adjustment before cutting the final pieces.
And yes, the front standard end of it comes out rectangular while the rear standard end is somewhat square.

[David Lobato]

Your skills as a photographer are apparent in your camera photos. The lighting is very well done as are fine details in and of the camera. Your lighting technique has perfect contrast between the metal part highlights and the dark areas. The wood textures look beautiful, as well as the closeup photos. The tripod is a work of art in itself. You are capable of producing great photos with this wondrous camera.

[blindpig]

Really beautiful job,well done.I appreciate the work you've done but mostly the design and the time spent on it are remarkable.

[Kerik Kouklis]

I had an Anthony and Scovill 14x17 that weighed 19 lb. I put many hundreds of sheets of film through that camera. But, it did not hold a candle to your beautiful design, both in terms of form and function. I like your design sense very much. Looking forward to seeing what you do with it.

[ederphoto]

Wow ! Congratulations ! You've just designed one of the most beautiful field cameras ever ! Now you can start mass production . I'd love to have one . I'm in love with this camera !

[radii]

Thank you everybody for the kind comments.

The glamour shots of the camera aren't misleading, some of the functionality however isn't where I'd like it to be.
Aluminum has the worst friction coefficient and has therefore turned the travel of the rear standard stabilizer-nut, into a not-so-smooth operation (even with the addition of Teflon washers) ...conversely, the movement of the front standard carriage is so smooth (the lead screw is virtually resistance free yet without slack) that, depending on the extension and pull of the bellows, it's hard to keep the carriage in place (can be corrected with proper placement of the bellow support)...AND of course the sagging bellow ...and ...

[radii]

... You are capable of producing great photos with this wondrous camera.

Thank you very much.

I hope that some of that turns out to be true.

[Colin Graham]

Impressive work for sure!
Aluminum is a great material in so many ways but it does sucks mightily for friction surfaces. I've never tried anodizing to see if it helps, but have had good luck with UHMW film- https://www.mcmaster.com/#uhmw-polyethylene/=17p0pfa. Not perfect, but it does help quite a bit and seems a bit slicker than the teflon materials I've tried. As for bellows, I'll gladly take some sagging if it means there'e flexibility to use a wide range of focal lengths.

[Fred L]

speechless....simply a beautiful build and can't wait to see some work from this camera.

and if you ever decide to build film holders...I could use an extra 7x17 or so ;)

[radii]

Impressive work for sure!
Aluminum is a great material in so many ways but it does sucks mightily for friction surfaces. I've never tried anodizing to see if it helps, but have had good luck with UHMW film- https://www.mcmaster.com/#uhmw-polyethylene/=17p0pfa. Not perfect, but it does help quite a bit and seems a bit slicker than the teflon materials I've tried. As for bellows, I'll gladly take some sagging if it means there'e flexibility to use a wide range of focal lengths.

Interesting. Thanks for the link.

Anodized pieces are much slicker (and would open up new design possibilities), but I haven't found a reasonably priced service that does small custom pieces (except paintball guns and yoyo amateurs) and the entry price to do it myself is just too damn high.

The other option would be to use Delrin in those friction places maybe. Once cut though, it looses it's factory shine and it's impossible to restore that.

[Pali K]

This is a gorgeous camera! Absolutely stunning workmanship.

Do you mind sharing the details for the ground glass?

Pali

[denverjims]

You're not planning to use it, are you? :)
Donating to MOMA would be more appropriate.
The first scratch would make me cry...

Beautiful!

[radii]

This is a gorgeous camera! Absolutely stunning workmanship.

Do you mind sharing the details for the ground glass?

Pali

Thank you. Glad you like it.

The ground glass is 1/8" acrylic, laser scored on one side and hand ground with 400 and 600 grit silicon carbide powder on the other.
Mix a bit of the powder with water, and with another thick piece of acrylic, grind away (for hours in my case). As the slurry dries up, rinse it off and mix a new batch.
It's still hit or miss for me though. No matter what, some circular scratches always remain.

[radii]

You're not planning to use it, are you? :)
Donating to MOMA would be more appropriate.
The first scratch would make me cry...

Beautiful!

Thank you. Very kind.

[radii]

speechless....simply a beautiful build and can't wait to see some work from this camera.

and if you ever decide to build film holders...I could use an extra 7x17 or so ;)

Thank you.

As others have pointed out, making film holders is a ridiculously involved process for such a seemingly simple object. The tight tolerances, space restrictions, weight, light proofing etc..
Unless I'd have enough holders to make, to justify bundling machining setups to make it more efficient, I won't make one the side, just for fun. Never say never though ...

[Pere Casals]

Awesome !!!

Congratulations, there is way more than labour time there... with this stunning realization, you not only show refined skills in 3D CAD, but also you know how to work with noble materials, and you also give a lesson on style... Functional, very, very practical, but beautiful, beautiful and beautiful.

I feel you are proud of this baby !"

[radii]

Awesome !!!

Congratulations, there is way more than labour time there... with this stunning realization, you not only show refined skills in 3D CAD, but also you know how to work with noble materials, and you also give a lesson on style... Functional, very, very practical, but beautiful, beautiful and beautiful.

I feel you are proud of this baby !"

Ha! Thank you. Very kind of you.

Noble ...I like that ...

[Michael Roberts]

Just about the most beautiful thing I've ever seen. Congrats!

[baronvonaaron]

oh my god

[bob carnie]

Ok here is the stupid question of the day..

These new router cutters that work in these amazing ways, would it not be a piece of cake for one of you technical geeks be able to make
custom made Washers at any size requested..

Bobby needs a 30 x 40 vertical washer....

[interneg]

Ok here is the stupid question of the day..

These new router cutters that work in these amazing ways, would it not be a piece of cake for one of you technical geeks be able to make
custom made Washers at any size requested..

Bobby needs a 30 x 40 vertical washer....


Kienzle in Germany make a 5 slot one - about 4K-5K EUR depending on spec however...

Been contemplating one, but am of same thoughts regarding whether it can be done cheaper.

[jon.oman]

Wonderful, just wonderful! I can't wait to see the first image...

[bob carnie]

Kienzle in Germany make a 5 slot one - about 4K-5K EUR depending on spec however...

Been contemplating one, but am of same thoughts regarding whether it can be done cheaper.

I think any plastic company have the abilitys, plastic welding is something I am not familiar with but I have gone as far as sourcing out the plexi.
I would use the same plexi GREY OPAQUE as I use for my big trays, and router out the end and bottom plates, I have not figured out how to bring water
into the system and out... It would have to be a floor standing model on wheels or base and one would need a floor drain.. I think 6 1 inch slots would allow enough space to
wash a days murals ... I was thinking with the proper routering and welding under 2 K Canadian which these days could be around 50cents on the dollar.

4 or 5K Euro is too much and it would have to cook me dinners at the end of the day or mix me a good cocktail before I would pay that much.

[interneg]

I think any plastic company have the abilitys, plastic welding is something I am not familiar with but I have gone as far as sourcing out the plexi.
I would use the same plexi GREY OPAQUE as I use for my big trays, and router out the end and bottom plates, I have not figured out how to bring water
into the system and out... It would have to be a floor standing model on wheels or base and one would need a floor drain.. I think 6 1 inch slots would allow enough space to
wash a days murals ... I was thinking with the proper routering and welding under 2 K Canadian which these days could be around 50cents on the dollar.

4 or 5K Euro is too much and it would have to cook me dinners at the end of the day or mix me a good cocktail before I would pay that much.

From what I've seen of it, it's much the same as a giant version of the Nova style of washer - water in at bottom, removable dividers textured on one side, the waste water waterfalls over an internal septum at the top to the drain tube.

[radii]

Just about the most beautiful thing I've ever seen. Congrats!

Thank you

[radii]

Wonderful, just wonderful! I can't wait to see the first image...

Thank you

And yes, me neither ;-)

[Ron (Netherlands)]

Indeed impressive, but would like to know the investment in the machines one need to make these...apart of course from the build experience

[MAubrey]

Indeed impressive, but would like to know the investment in the machines one need to make these...apart of course from the build experience

Seconded. I have access to the relevant machines at a local makerspace shop, but I've never gone near them for lack of experience.

[Peter Collins]

stunning! gorgeous! amazing fit and finish!!

[Tav Walraven]

When do they do into assembly line production? My Bitcoins are ready to be traded!

[radii]

Indeed impressive, but would like to know the investment in the machines one need to make these...apart of course from the build experience

What I have access to, which is a 4' X4' CNC router with 12" clearance (can cut almost anything except ferrous metals) and other standard shop tools like a table saw, band saw, hand power tools, hand tools etc, would probably cost ~$35'000.-. Plus of course shop space.
All of that makes it easier and more efficient to make things, but a good table saw, hand router, perseverance and elbow grease can achieve equal results. They're just tools.

[Jim Graves]

WOW!!! ... just WOW!!!

[radii]

Finally, the first two contact printed pictures !!

Still have ways to go with nailing down developing times and contrast grade filters, tray agitation technique etc., but it's quite a rush to see a 100% hand made picture coming out of the fixer bath.

I apologize for the awful cell phone pictures.

https://i.postimg.cc/LXsW4vqj/1.jpg (https://postimg.cc/TyZ0CVJP)

https://i.postimg.cc/KzzZXPxH/2.jpg (https://postimg.cc/yJMqcSJm)

[Peter Collins]

¡another jaw on ground!

[Fr. Mark]

Wow! Looks great!

[fj55mike]

Wow, super impressed! I really like the adjustable leg supports on the tripod. Loads of amazing details throughout.

[Tin Can]

Wow!

I missed this during my haitus.

Great work.

[Dan Fromm]

Wow, super impressed! I really like the adjustable leg supports on the tripod. Loads of amazing details throughout.

Mike, I think the tripod is a superior imitation Ries. Not to take anything away from the OP, but Ries tripods embody good ideas that are well worth stealing. And improving on.

[Colin Graham]

Interesting. Thanks for the link.

Anodized pieces are much slicker (and would open up new design possibilities), but I haven't found a reasonably priced service that does small custom pieces (except paintball guns and yoyo amateurs) and the entry price to do it myself is just too damn high.

The other option would be to use Delrin in those friction places maybe. Once cut though, it looses it's factory shine and it's impossible to restore that.

Yeah, I could never justify the expense or the space required to anodize at home.

Small profiles in Delrin cut well with router bits- I've used a Whiteside (https://www.whitesiderouterbits.com/collections/spiral-router-bits) downcut spiral bit in my micro mill and it left a pretty decent finish at slower speeds around 1500 rpm. On a router the same bit will melt it as much as cut. A single-cut file also leaves a surprisingly good finish on the cut ends of bar stock. I've never tried to surface a large surface area of Delrin sheet stock before though. And you're getting a truly amazing finish on your metalwork, so our standards for finish quality might be a little different!

One warning about the adhesive-backed UHWM film I linked earlier, the cut edges leave an adhesive burr that can gum up the parts and defeat the point of using it, it needs to be burnished along those edges.

[radii]

Mike, I think the tripod is a superior imitation Ries. Not to take anything away from the OP, but Ries tripods embody good ideas that are well worth stealing. And improving on.

It is definitely a Ries imitation, but in no way superior. I've never used a Ries myself, but can only imagine how smooth and secure the leg support is.
The tolerances in the moving sleeve that grips the shaft , had to be within 0.003" to get the right amount of friction, which I could only achieve with a few amateurish paper shims.
The lever principle rally kicks in when the legs are extended and it's hard to strike the right balance between ease of movement/adjustability and securely positioning the legs.

In other words, hats off to the original Ries !!

[radii]

Yeah, I could never justify the expense or the space required to anodize at home.

Small profiles in Delrin cut well with router bits- I've used a Whiteside (https://www.whitesiderouterbits.com/collections/spiral-router-bits) downcut spiral bit in my micro mill and it left a pretty decent finish at slower speeds around 1500 rpm. On a router the same bit will melt it as much as cut. A single-cut file also leaves a surprisingly good finish on the cut ends of bar stock. I've never tried to surface a large surface area of Delrin sheet stock before though. And you're getting a truly amazing finish on your metalwork, so our standards for finish quality might be a little different!

One warning about the adhesive-backed UHWM film I linked earlier, the cut edges leave an adhesive burr that can gum up the parts and defeat the point of using it, it needs to be burnished along those edges.

Thanks for the pointers Colin.

[william.j.dwyer@usa.net]

What did you use for dark slides? It looks plastic? Garolite? CF?

[radii]

What did you use for dark slides? It looks plastic? Garolite? CF?

Yes, 0.03" Garolite XX from McMaster

[Paul Kinzer]

Yes, 0.03" Garolite XX from McMaster

Wow, I would have thought that 1/32" would be too thin for such a large sheet. I'm contemplating a 14x17 build myself (though nothing like as sweet as yours!) and was wondering about Garolite and how thick to get it. Do you find that it really is thick enough, now that you've got it done, or would 1/16" maybe be better? I'm in no way criticizing; just curious. And I ask because I read in another thread somewhere that someone thought 1/16" would be too thin for an even smaller holder, which seemed wrong to me. You're the one who's had it in your hands, so no one would know better.

[radii]

Wow, I would have thought that 1/32" would be too thin for such a large sheet. I'm contemplating a 14x17 build myself (though nothing like as sweet as yours!) and was wondering about Garolite and how thick to get it. Do you find that it really is thick enough, now that you've got it done, or would 1/16" maybe be better? I'm in no way criticizing; just curious. And I ask because I read in another thread somewhere that someone thought 1/16" would be too thin for an even smaller holder, which seemed wrong to me. You're the one who's had it in your hands, so no one would know better.

1/32" is definitely thin and can easily snap and break if mishandled. It is however 100% light proof and the weight savings compared to a 1/16" thickness, just made sense to me. Maybe even more of a deciding factor were the space restrictions in the film holder construction itself. There just isn't that much"meat" left after fitting the 1/8" septum into the middle of ~0.79" thick stock. For smaller holders, a 1/16" thick septum might work ok, therefore freeing up some space on either side for thicker material.

[Paul Kinzer]

Thanks! What you say makes a lot of sense. It looks like you used MDF for the septum, and lightened it by removing some material.

My own camera will be made with much less precision because I'll be using inexpensive shop tools. But as you said, the film holder needs to be precise, as does the ground glass holder. I got a few sheets of ruined 14x17 inch x-ray film today, and I can start building around them, and then outward from there.

Thanks again!

[radii]

Thanks! What you say makes a lot of sense. It looks like you used MDF for the septum, and lightened it by removing some material.

My own camera will be made with much less precision because I'll be using inexpensive shop tools. But as you said, the film holder needs to be precise, as does the ground glass holder. I got a few sheets of ruined 14x17 inch x-ray film today, and I can start building around them, and then outward from there.

Thanks again!

The septum is actually also Garolite XX, .125" thick. The beige color was cheaper than pure black. The machined concentric circles were an effort to relieve the stress in the material and flatten it out (the raw sheet had a slight bow to it).

Good luck with your build.

[formatoff]

Super job! Exceptional set with a lot of details looks just great!

[Paul Kinzer]

The septum is actually also Garolite XX, .125" thick. The beige color was cheaper than pure black. The machined concentric circles were an effort to relieve the stress in the material and flatten it out (the raw sheet had a slight bow to it).

Good luck with your build.

Ah, I see now! Did the circles work?

[John Layton]

As I've mentioned in another thread...this is so very breathtaking! I'd love to see it in person sometime!

I do have one question regarding your choice of dark slide material. In the photo of the film holder laid out flat...it looks as though the dark slide bows downwards, to the point where it looks like (to my eyes) like it actually makes contact with the septum. I'm guessing that if this is indeed the case, then it would only be a "problem" while loading/unloading films - in that there may be some potential for scratching an emulsion. Perhaps this is a non-issue, but if I were you I'd look very carefully at your processed negatives, and if you see axially located linear scratches, then maybe a very fine polish on the dark slides leading edges (maybe you've already don this?) would alleviate any tendency for such scratching, and if not, then perhaps you might think about using a thicker dark slide material. Then again...not all scratches actually show up on a print!

[radii]

Ah, I see now! Did the circles work?


Actually it did take care of about 75% of the bow, and the straight and rigid walnut stiles did the rest.

[radii]

As I've mentioned in another thread...this is so very breathtaking! I'd love to see it in person sometime!

I do have one question regarding your choice of dark slide material. In the photo of the film holder laid out flat...it looks as though the dark slide bows downwards, to the point where it looks like (to my eyes) like it actually makes contact with the septum. I'm guessing that if this is indeed the case, then it would only be a "problem" while loading/unloading films - in that there may be some potential for scratching an emulsion. Perhaps this is a non-issue, but if I were you I'd look very carefully at your processed negatives, and if you see axially located linear scratches, then maybe a very fine polish on the dark slides leading edges (maybe you've already don this?) would alleviate any tendency for such scratching, and if not, then perhaps you might think about using a thicker dark slide material. Then again...not all scratches actually show up on a print!

The slide definitely does flex to the point of touching the septum. The leading edge there is rounded and sanded smooth to facilitate the entry into the bottom flap. I have not checked my negatives for faint scratches in that area, but surely will do so now. Thank you for the heads up.
A 1/16" thick dark slide would be a lot stiffer for sure, I just wasn't comfortable with it during the design phase and quite frankly, don't really regret my choice either. The squeaky folding mechanism and sagging bellows are infinity greater issues for me to worry about ;-)

[John Layton]

Perhaps if you could find a way to carefully hold the middle of the slide above the film's surface as you close the slide?

[Paul Kinzer]

The slide definitely does flex to the point of touching the septum. The leading edge there is rounded and sanded smooth to facilitate the entry into the bottom flap. I have not checked my negatives for faint scratches in that area, but surely will do so now. Thank you for the heads up.
A 1/16" thick dark slide would be a lot stiffer for sure, I just wasn't comfortable with it during the design phase and quite frankly, don't really regret my choice either. The squeaky folding mechanism and sagging bellows are infinity greater issues for me to worry about ;-)

For saggy bellows support, I'm wondering about those ringed tabs I often see on photos of the bellows on older LF cameras, especially those really long ones. Like those seen here (http://www.largeformatphotography.info/century/Image10.jpg). They are meant to have a rod slipped through them, like this (http://www.filmholders.com/8x20korona.jpg) (though the camera in that image doesn't seem to have the tab actually being used) in order to hold up the bellows. Something like a telescoping radio antenna would be ideal for the rod, though not really heavy-duty enough. A brass tube sliding within another would look nice, and I know my nearby hobby shop has brass tubes of varying diameter.

[John Layton]

...actually, from Radii's photos, it looks like an elegant solution to bellows sag is already in place underneath the bellows (wondering about the fore-and-aft adjustability of this?)...although perhaps one location might not be enough for certain situations.

[Paul Kinzer]

...actually, from Radii's photos, it looks like an elegant solution to bellows sag is already in place underneath the bellows (wondering about the fore-and-aft adjustability of this?)...although perhaps one location might not be enough for certain situations.

Oh, yes, both elegant and beautiful!

[radii]

Perhaps if you could find a way to carefully hold the middle of the slide above the film's surface as you close the slide?

yes, maybe some double stick tape to pull it up, or close the slide in the upright position only? Hard to do with my changing tent setup ...

[radii]

For saggy bellows support, I'm wondering about those ringed tabs I often see on photos of the bellows on older LF cameras, especially those really long ones. Like those seen here (http://www.largeformatphotography.info/century/Image10.jpg). They are meant to have a rod slipped through them, like this (http://www.filmholders.com/8x20korona.jpg) (though the camera in that image doesn't seem to have the tab actually being used) in order to hold up the bellows. Something like a telescoping radio antenna would be ideal for the rod, though not really heavy-duty enough. A brass tube sliding within another would look nice, and I know my nearby hobby shop has brass tubes of varying diameter.

I did consider that, but didn't know how to attach the tabs to the fabric without introducing the possibility of eventual light leaks.

[radii]

...actually, from Radii's photos, it looks like an elegant solution to bellows sag is already in place underneath the bellows (wondering about the fore-and-aft adjustability of this?)...although perhaps one location might not be enough for certain situations.

The supports I made are somewhat adjustable (the carbon fiber rod can be moved forwards and backwards, depending on bellows extension), and are far from ideal, BUT the bellows have yet to show up in a picture. So it could be argued that they work as intended, visually though, my maker's pride is hurt ! ;-)