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36cm2
7-Feb-2020, 13:43
Hello all. I'm finally getting around to finishing the updating of a large older view camera that I purchased many years ago (see pic below, I just have the camera without bellows, back or base). Before I purchase a new bellows and build a back for it, I was wondering if I could get some practical insight from those of you with greater experience in what I would like to achieve.

I intend to use the camera for alternative processes, mostly ambrotypes. Mostly portraits (head and shoulders / 3/4 body) and some still life. The back will accommodate a maximum exposure size of 15" x 15", but will have reducing inserts for lesser sizes (e.g., 8x10 / whole plate). Lenses will likely be a period 19" that I believe covers the 15", as well as mid-century design 15" and 12" lenses for smaller formats. Lighting will be by large strobe (3200 w/s key, with lesser support lighting).

Assuming that the camera is provided a stable base (which I'm working on), it seems to rack out without terrible strain to a max bellows of about 52". It can go further, but I fear the stress of doing so and also hope there would be no need to do so. I was intending to purchase a bellows with that 52" length.

I've gone through a whole series of bellows length / focal length / subject distance / DoF calculations to estimate how this will all work in practice, but I'm hoping for some further insight from those well-versed in a similar experience.

My specific questions would be:

1. Is purchasing a 52" bellows adequate / sensible?

2. What kind of subject working distances, bellows extension and portrait types (e.g. head/ head/shoulder / 1/2 body) would you typically be utilizing in this large of a format, particularly if you were utilizing the full 15" square format and a 19" lens for example? I know that DoF is a great challenge in this context, but just trying to zero in on some practical clarity.

I appreciate any input you can provide. Apologies if any of my questions seem rehashed. I have done the calculations, as well as a good amount of forum post reviewing, and believe I'm in the right ballpark in my thinking, but some corroboration or correction is always helpful. Thank you.

Best regards,
Leo

200403200403

Gary Samson
7-Feb-2020, 15:03
Hi Leo,
Since you want to make Ambrotype portraits with your camera, I would recommend that you think about increasing the amount of lighting for that purpose. I use 4800 watt seconds for my wet-plate portrait work making 5x7 and 6.5x8.5 inch plates at f5.6. What is the speed of your 19inch lens? You have to double your light for each stop you close down, so if I shoot at f8 I would need 9600 watt seconds. You will need even more light if you move in closer for a head and shoulders portrait as you will have bellows extension compensation to contend with. If you are making still lifes, you can of course do multiple pops of the strobe to build up enough light for the f stop you are using.

36cm2
7-Feb-2020, 15:06
Thank you, Gary. I thought 3600 would be enough, but it's great to see your notes. My 19" is f/7, so your practical note on the head and shoulders is very helpful.

Two23
7-Feb-2020, 21:47
I shoot tin type. With flash placed 3 feet away, lens is f4, straight flash no modifier, I use 2600ws. I think I'd need twice that for ambro.


Kent in SD

Steven Tribe
8-Feb-2020, 02:59
I have a fair number of these Continental studio cameras (about 5).

You talk about 15x15" format, which seems like a very large studio camera. I think that this is only possible if you are planning to use the "drop down" (Early type) plate holders - as shown in the stock photo you enclose. Later camera, after around 1890, have more complicated systems which are unable to utilise the full internal dimensions. Because of this, the usual plate size on these heavy duty studio cameras was around 18x24cm in a square plate holder 24x24cm.

This also means that the bellows is not quite as long as your calculations would suggest, but they are over a meter! If you post the dimensions of your front and rear standards, I can check the extension of the coupled base/bellows length of my camera closest to yours. I note that the bellows in the illustrated camera seems to have lost the folding/sliding mechanism underneath to minimise bellows droop!

I have ask whether I am right in thinking that you are without the base, the back element, any sort of plate holders, ground glass frame and the bellows? This seems to make your project pretty difficult.

36cm2
9-Feb-2020, 06:55
Hi Steven. Thanks for the message. You and I communicated regarding this camera many years ago. You were very helpful then, and now again! Your assessment is, as usual, correct. I'm building a groundglass back and plateholder back for the camera that should permit utilization of the full back opening, which is 15.5 x 15.5 inches. I don't disagree that the project will take some work; but that is also the joy of it's being a project. I'll see if I can get the measurements to you for the front and rear standards. I recall the attachment points for the bellows being 17.75" square. Thanks again and have a great day.

36cm2
12-Apr-2020, 13:15
Just an update to all the helpful people here. I hope you are all doing well in these turbulent times and my best wishes to all of you facing serious challenges. Lockdown has permitted greater time toward this project. The camera is fully functional again and on its way toward some serious wetplate as I ramp up a couple of more lenses that I'm seeking and move toward the chemistry side. The photos that follow depict progress along the way, first building a custom back to support an 8x10 and 5x7 Graflex Studio sliding back that I procured, then a lensboard adapter to go from 8x8 to my standard 8x10 size, down to 4x5 format (although I don't have many lenses on that size board that will work at minimum bellows on this beauty. I'm not really a woodworker, so while these things may look easy enough to those with skills, it was a valuable learning journey for me. In the end, it all fits and is light tight and works well; and for that I am grateful. I also started constructing bellows for it, but in the end I realized that for this size bellows I was just much better off purchasing from the pros - many thanks to Keith at Custom Bellows - fine work and a quick turnaround, even from overseas. Anyway, an update to help you get your mind off more serious things. Have an excellent day and stay well.

36cm2
12-Apr-2020, 13:18
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36cm2
12-Apr-2020, 13:20
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36cm2
12-Apr-2020, 13:22
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Steven Tribe
13-Apr-2020, 12:19
Thanks for the update!

Most of the top-of -the-rangeContinental cameras - with bellows of 100cm or more - had a support system to prevent bellows droop or bellows wear on the underside.
When the distance between the bottom of the bellows was around a cm or less, there was an applied metal frame around a central pleat with tiny wheels underneath which ran on the wooden base.
With larger distances - about 5cm - there was a series of hinged flaps attached to the front and rear standards which expanded and contracted along with bellows movement.

36cm2
13-Apr-2020, 14:58
Thanks Steven. I have the hinged flaps mechanism under there. Hopefully the bellow don't wear too quickly, even with that, as they do still rub slightly with extension and contraction. Many thanks for all of your help. I have to say, I really love the design of these Continental cameras. If the cost wasn't prohibitive I would definitely be searching for an excellent condition large one to ship over and preserve. This one will be a workhorse and for that it is ideal, but a well-kept one of these must really be a sight to behold.

36cm2
13-Apr-2020, 15:00
And, by the way, I have not given up on the larger format back. Just want to start with the 5x7 and 8x10 formats, as they are most accessible in the short term. My aspiration is that the 11x14 and 15x15 backs will be designed and built shortly, hopefully by end of summer.