Building an 8x10 Large Format Camera. Help and ideas are much appreciated.

[DiegoV]

Hi everyone.
That is a lot of useful info, thank you very much!
NedL, that was a very detailed post, I really appreciate you taking the time to write that.
wilper, your design looks very interesting; the one thing I'm not sure about is the focusing system, as I'd like to shoot portraits at larger apertures, thus needing to have a precise focusing system.

That said, I think I'm gonna use a bit of what everyone said. I'll start by keeping the camera simple, using a box design and no shutter. The lens is going to be also a simple design like the one we used in the room camera. The one thing I'll have to be a bit rigorous about is the focusing system for the reasons I stated before... So I'll have to build a focusing screen and (maybe) a film holder. Maybe I can just use a changing bag and tape the film/paper to the focusing screen?

Or maybe I could add another lens in a separate chamber just for focusing and having the film/paper on the other chamber with a different lens. Like a TLR, basically.

Haha, my head is spinning with so many ideas!

Thanks a lot guys, you are awesome

 

[wilper]

Hi everyone.
wilper, your design looks very interesting; the one thing I'm not sure about is the focusing system, as I'd like to shoot portraits at larger apertures, thus needing to have a precise focusing system.

Even having a fixed focus camera should not preclude sharp portraits with large apertures.

Have a model sit for you when you install the spacers for the "film holder". Compose a picture by observing the projected image and fasten your spacers accordingly.

Then fasten a chain to the front of the camera and light a candle in front of the camera. Move the candle back and forth until the projection is sharp. Stretch the chain to the candle and cut/mark it at the correct length.

Now you can get the right distance to the subject by checking against the chain.

Not very fancy, but it should give you pretty good control of the focus.

 

[DiegoV]

Even having a fixed focus camera should not preclude sharp portraits with large apertures.

Have a model sit for you when you install the spacers for the "film holder". Compose a picture by observing the projected image and fasten your spacers accordingly.

Then fasten a chain to the front of the camera and light a candle in front of the camera. Move the candle back and forth until the projection is sharp. Stretch the chain to the candle and cut/mark it at the correct length.

Now you can get the right distance to the subject by checking against the chain.

Not very fancy, but it should give you pretty good control of the focus.

You are absolutely right.
The only "downside" being, everyone would have to be at the same distance from the camera.
I think I'll still try to build some sort of focusing system (there's something I really like about that "freedom" -- can't really explain what) but if for some reason I decide not to, this is a system I can see myself using. Thank you!

 

[removed account4]

hi diegoV

i have made simple cameras with a way to focus them.
what you need to do is make a "friction mount" for you lens or the board
your lens will be mounted on. you will slide the lens ( or board) in and out of the camera
and you will be able to focus. you can also make it so the lens board tilts and shifts because it is friction mounted
you can have it at an angle and do your own bit of distortion.
so the back end of your camera remains stationary, ( allowing you to have a film back &c that is standard
and use standard film holders &c ) the camera will be a fixed box, but the lens moves.
you can put marks inside the box to correspond to pre measured strings with knots on them &c if you want ...
know where infinity is, know were 3.5 meters is &c .. and it makes it easy for you. stopping your lens down a little bit
will also make sure your subject is in focus ( if you want that, that is ).

good luck with your project ! ( i liked your video too )
john

 

[pdeeh]

With the foamcore sliding boxes I've made, locking focus is the biggest headache I've had.
Because the boxes only partially fit properly (a shortcoming of both material and my craft skills), while I can focus with good accuracy, the business of removing the gg and inserting the holder introduces all sorts of opportunities for moving the focus.
Fortunately for my sort of snapping, a bit of focus shift is rarely the end of the world, but if Iwere taking portraits it might become a royal pain

 

[NedL]

Mine focuses fairly smoothly and stays in place well ( my film and GG holders drop into a slot from above, so they do not require attaching to the rear ). But as soon as the camera warms up ( black foamcore in the sun! ) the focus starts to stick and get difficult. You'd think when the sun hit it, the outer box would expand and make them slide easier, but that's not what happens. If it gets hot enough it really seizes up. I think all such cameras suffer from their simplicity in some way... I think Joe VanCleave uses stick-on felt sheets on the sliding surfaces and that might solve both of these problems.

 

[SchwinnParamount]

Barry and I were into an 8x10 camera building project a few years ago. Barry produced plans for the camera which he sold for a while. He also produced a good manual on making bellows.

(there was a url link here which no longer exists)

 

[DiegoV]

hi diegoV

i have made simple cameras with a way to focus them.
what you need to do is make a "friction mount" for you lens or the board
your lens will be mounted on. you will slide the lens ( or board) in and out of the camera
and you will be able to focus. you can also make it so the lens board tilts and shifts because it is friction mounted
you can have it at an angle and do your own bit of distortion.
so the back end of your camera remains stationary, ( allowing you to have a film back &c that is standard
and use standard film holders &c ) the camera will be a fixed box, but the lens moves.
you can put marks inside the box to correspond to pre measured strings with knots on them &c if you want ...
know where infinity is, know were 3.5 meters is &c .. and it makes it easy for you. stopping your lens down a little bit
will also make sure your subject is in focus ( if you want that, that is ).

good luck with your project ! ( i liked your video too )
john

Hello and thanks a lot for the feedback (and I'm glad you liked the video!)
I haven't had enough free time lately to dedicate to this project but I'm seriously considering ditching infinity focus (because I want to shoot portraits after all, so I don't really need it) and go for something like the box focusing system but moving the lens, instead of the film -- like you're saying.

Also -- and forgive my dumbness -- what's a GG holder? It's like a...film holder? :confused: I'm feeling really dumb now, sorry.

 

[NedL]

what's a GG holder? It's like a...film holder? :confused: I'm feeling really dumb now, sorry.

Not at all dumb, really and seriously! A "ground glass" holder, i.e. the focus screen. If you make film/paper holders, it is handy to make a GG holder that puts the front plane of the focus screen ( ground glass or other ) exactly where the front plane of the film will be.

 

[DiegoV]

Not at all dumb, really and seriously! A "ground glass" holder, i.e. the focus screen. If you make film/paper holders, it is handy to make a GG holder that puts the front plane of the focus screen ( ground glass or other ) exactly where the front plane of the film will be.

Oh, Ground Glass! Thanks a lot! English being my second language kinda makes it hard to think properly sometimes.
So yes, I'll build a GG holder and figure out a way to place the paper/film exactly where the focus plane is. It's gonna be fun haha

 

[NedL]

Your English is incredibly good; I would not have guessed it is a second language. The way you use idioms is smooth and natural and normal, and that is often the giveaway. Have fun building your camera!

 

[DiegoV]

Your English is incredibly good; I would not have guessed it is a second language. The way you use idioms is smooth and natural and normal, and that is often the giveaway. Have fun building your camera!

Thank you! I'll post here as soon as I have some (good, I hope) news

 

[paul_c5x4]

So yes, I'll build a GG holder and figure out a way to place the paper/film exactly where the focus plane is. It's gonna be fun haha

Have a look at how Dean Jones did the GG screen on his Razzledog conversions - Unfortunately, his site no longer exists, so here is an archived copy:
http://web.archive.org/web/20120914...es.ihug.com.au/~razzle/Razzlok_/razzlok_.html

If you look at the first image, it is a standard 5x4 film holder with the insides removed and the ground glass dropped in. The idea will scale up for 10x8 or larger.

 

[DiegoV]

Have a look at how Dean Jones did the GG screen on his Razzledog conversions - Unfortunately, his site no longer exists, so here is an archived copy:
http://web.archive.org/web/20120914...es.ihug.com.au/~razzle/Razzlok_/razzlok_.html

If you look at the first image, it is a standard 5x4 film holder with the insides removed and the ground glass dropped in. The idea will scale up for 10x8 or larger.

Thanks for the link
It's indeed "a bloody good idea" like he says on that first image

 

[John Koehrer]

For a sliding box camera velvet ribbon can work as both a light trap and friction for the focusing box. It does come in different widths.
Depending on the size of the moving box you could use two 15mm strips on each side. that would reduce the tendency to droop when it focused closer.

 

[pdeeh]

I hate it when I'm in close and it droops

 

[DiegoV]

For a sliding box camera velvet ribbon can work as both a light trap and friction for the focusing box. It does come in different widths.
Depending on the size of the moving box you could use two 15mm strips on each side. that would reduce the tendency to droop when it focused closer.

Thank you. Solves two problems at once -- I like that

 

[Joe VanCleave]

Mine focuses fairly smoothly and stays in place well ( my film and GG holders drop into a slot from above, so they do not require attaching to the rear ). But as soon as the camera warms up ( black foamcore in the sun! ) the focus starts to stick and get difficult. You'd think when the sun hit it, the outer box would expand and make them slide easier, but that's not what happens. If it gets hot enough it really seizes up. I think all such cameras suffer from their simplicity in some way... I think Joe VanCleave uses stick-on felt sheets on the sliding surfaces and that might solve both of these problems.

My 8" x10" nested box camera has the rear box half (with removable GG and film holder) sliding into the larger fixed front half, which itself is permanently mounted to the plywood base plate. There's also an inner, second "wall" in the fixed front half of the box. So that the rear sliding box moves inside the slot between the front box half's outer wall and this inner wall. The reason for this configuration is light-integrity; a light-leak has to pass in the gap between both box halves all the way toward the front, then reflect 180 degrees back toward the rear of the camera, then make two more 180-degree bends, in order to fog the film. With this configuration, I don't need a tight fit between the fixed and movable halves of the box, and hence no problems with friction.

While implementing this design in wood would be a considerable undertaking, with foam core board and gaffer's tape it's pretty easy.

Also, because of the thickness of the foam core walls of the front portion of the box, the rear sliding portion is raised up above the plywood base by one thickness of foam core (the bottom surface of the front box); to prevent the sliding box from binding up in its movement, there's a spacer piece on the bottom of the sliding box that permits it to slide on the plywood base. This keeps the rear sliding half aligned parallel with the fixed front half.

As for the adhesive craft felt, I do use it for lining the inside of the box, as it's a cheap and easy method for preventing light reflections, especially when building with materials like foam core board, whose outer paper layers can't stand to get wet (as from paint or varnish - ask me how I know this!) without delaminating from the inner foam core.

~Joe

 

[NedL]

Aha! Thanks Joe, that make perfect sense. Next version will have inner walls. A fairly simple modification to the existing camera.