New Diy 16x20

[illumiquest]

A couple of years ago I banged out a 16x20 camera with some bits from the hardware store and several beers. That camera's worked great and I've shot a whole bunch of ambrotypes with it but it's definitely not a looker and is a bit cumbersome and limited.

So I've decided to start out on a new version, this time using a bit more planning, measuring and cash on materials. The lens I mostly use is a 500mm so the full rail will be 4' long and I'm stealing the Sinar method of extension rail mating to be able to add more should I find a much longer lens in the future.

The biggest challenge is going to be figuring out fine focus adjustment on the back standard, I'm looking at a rack and pinion type with a cross roller linear bearing (or four) to hold things aligned while still moving.

Here's a few quick sketches of the plan as it stands now. Any input and advice welcome.

 

[Eric Rose]

Pretty ambitious!

 

[John Layton]

Carbon Tube w/Keyway to keep things right? Nice! Sounds like you won't need 4' w/500mm unless you're wanting to go quite close. You could probably do something like 30 inches...and create some way to add an extension if you need this. Try to find a bellows that's reasonably thin so it doesn't fight with your movements - especially at long/short extensions/significant movements. Custom Bellows in the UK make really nice ones.

Make sure back movements are complete...and have back focus as the front standard on this format can get pretty distant with longer lenses/close focus! Also think about separating your front rise/fall from axial tilt function - a real pain when they're combined as a heavy lens will drop as you attempt to tilt.

Roller bearings might be overkill (I investigated these years ago...the source was W.M. Berg) - if you do this...just make sure to pre-load (look at "pre-load" washers) your focus so it doesn't slide all over the place! Add a good focus lock to this also...think about doing this perpendicularly to the focus axis (with a split shaft-clamp) to eliminate the cross-interference that exists in many coaxial focus-locks. Good luck!

 

[John Layton]

oh...16x20 (was thinking 11x14). Yup...you're gonna need a long rail! But I'd still recommend something like 30inches, then add one or more extensions to this if you need them. Also...for this format - your carbon tube (if your renderings indicate this) will need to have a largish OD to provide sufficient strength/stability. Maybe contact Richard Ritter in VT. for more info on these tubes.

 

[John Layton]

pps...do think about using two carbon tubes side by side - much sturdier and more versatile design/function wise!

 

[illumiquest]

Thanks John, I've already been using this lens and it does a nice close portrait at about 32", I also have a 28" lens that is going to require quite a bit more pull hence the longer tube. Really I'd like to have the main tube about 20" long and then an extension. I have a 14" lens that's a super wide that I was going to use and having the rail sticking way out the back is a pain in the ass if not needed.

I dropped Ritter as well to see if he has any advice.

Thanks!

pps...do think about using two carbon tubes side by side - much sturdier and more versatile design/function wise!

 

[fdonadio]

For really long bellows extension, I think you'll need an intermediary standard and two bellows sections: one straight and one tapered. Otherwise, I think the bellows will sag a lot. But I think you know that.

 

[illumiquest]

New bellows from Keith at CustomBellowsUK. Haven't received them yet but he built them in less than a week and I can't imagine that I'm going to be disappointed.

 

[illumiquest]

Did some revisions to my focusing mechanisms to reduce parts and increase rigidity. It'll now have two main rail clamps 5" apart with 16mm tubes fixed between them and a ball screw to control fine focus adjustment. Bellows arrive on Monday and I can finally start cutting metal.

 

[illumiquest]

Finished camera at its first shoot with Redbull in Los Angeles.

There's definitely some things I'll do to improve its use when I get home but overall it performed about how I expected.

 

[Andrew O'Neill]

Beautiful! Well done!

 

[36cm2]

That is an awesome, awesome beast.

 

[Eric Rose]

Love the metal work!

 

[jon.oman]

Wow! That looks fantastic!

Can you post an image made with the camera?

 

[awty]

Great work, really well done.
How does the fine tuning work? Can you post a close up picture? ....also how the ground glass panel hinges away to fit the photo plates, I cant work it out., thats if its not top secret of coarse.

 

[grahamp]

Modern industrial chic!

 

[fdonadio]

Great work, really well done.
How does the fine tuning work? Can you post a close up picture? ....also how the ground glass panel hinges away to fit the photo plates, I cant work it out., thats if its not top secret of coarse.

He posted a lot of videos on Instagram, so I guess it’s not a secret.

It’s a very clever design, using pneumatic thingies that look like shock absorbers... or like those things that hold the baggage compartment door open in a car.

Sorry, I am not a native English speaker, so I can’t imagine how that part is called.

@illumiquest Is it possible to rotate the back to shoot in landscape format?

 

[Qebs]

Hello Mr. Clement / @illumiquest,

Sorry if you are getting tons of unsolicited private messages or emails, (which I didn't want to do), but I was wondering if you could tell us what lens you are using?
Are you getting any vignetting?

My name is Kevin, from Toronto Canada, and I really would like to get into 16x20 tintype portrait photography.

Thank you for reading this and have a great week/Spring Season!

Cheers to you,
Kevin H.

 

[AgX]

Sorry, I am not a native English speaker, so I can’t imagine how that part is called.

Gas Spring

 

[fdonadio]

Gas Spring

Thanks, AgX! Makes sense. It acts like a spring and is filled with gas...

 

[illumiquest]

Kevin H.[/QUOTE]
Hey Kevin, I use a 500mm f/4.5 primarily which works well for portraits but does vignette at infinity. I also have a 14" f/8 that just barely covers, a 600mm f/11 and a really old rapid rectilinear which seems to be about 40".

Paul, I'm using a gas spring between two a-arms which hold the glass frame down and allow it to be opened for the film back. The advantage of the gas struts is they don't slam shut and provide even pressure across their entire movement. The fine focus adjust consists of two clamps which hold to the main rail and are connected with two rods and a lead screw. This screw when rotated pushes the back mount forwards or back. It's very smooth, accurate and self locking.

 

[illumiquest]

Took a few more photos of the camera showing some of the details. I've also added a fresnel lens to the focusing screen which helps with seeing the entire image.