Rodenstock Rodagon 360mm

[Greg]

The studio camera on heady tripod should be rigid enough, as it's used to take the original picture, which in itself requires good alignment tolerances.

A lot depends on what 8x10 camera you start with. In the late 1970s, I tried it with a wooden Burke & James Commercial view camera and maintaining alignment was a huge ever present problem which derailed the whole project. In the 1980s I tried the same with an 8x10 Sinar Norma mounted on a Linhof Heavy Duty copy stand. It actually worked, but back then LED panels were unheard of and fabricating an evenly lit and bright 8x10 light source proved to be the Achilles Heel of that project. If I were to attempt that project again, I think I would try to find an 8x10 Sinar that was made for copying artwork and didn't have any movements (heard that they indeed existed but I have never seen one FS). An 8x10 LED light panel would seem to be easy enough to acquire, but I wonder if it would be bright enough for enlarging?

[Vaughan]

... you still might want to check with a laser.

Can you describe the process please? Thanks.

[kfed1984]

Can you describe the process please? Thanks.

I saw it somewhere on youtube, I think he's referring to something like this:

https://www.youtube.com/watch?v=UZQo0ZTYATg
https://www.youtube.com/watch?v=1B_h9i61zos

As a side not; I think the guy in the first video is using an LED array light source, something I could put together or maybe an LED light-tablet could do the job.

[kfed1984]

...A lot depends on what 8x10 camera you start with..... An 8x10 LED light panel would seem to be easy enough to acquire, but I wonder if it would be bright enough for enlarging?

I have an 8x10 Cambo view camera with lots of movements, so not too rigid.

When I get home tonight I will attempt to rig up my 8x10 camera with an LED light tablet, a negative, and a 300mm lens, to test if light intensity is good enough. I will have to use some hockey tape and a dark cloth. Maybe a two-by-four as well.

[interneg]

I got the lens for $400, do you think it was a good deal? Seemed like it to me, as I saw this lens for a lot more last year. Looks like lenses have dropped in price this season.
Attachment 244478

That looks like it's got a custom made De Vere mount on it for a 5108 (normally the 300 is the longest Rodagon the 5108 will take).

[kfed1984]

That looks like it's got a custom made De Vere mount on it for a 5108 (normally the 300 is the longest Rodagon the 5108 will take).

Yeah I don't know what that thing is, either way it will come off.

[kfed1984]

So I think the basic concept works out, with a 300mm Schneider lens. The LED source is bright enough.

Just need to hold all this together better, maybe with aluminum extrusions, and some 3D printed and wooden parts.

[kfed1984]

So the idea is worth pursuing. My existing camera lens may also work like someone else mentioned. But maybe the specialty enlarger lenses provide better quality and flatness for bigger enlargements.

The LED source is definitely bright enough and appears to be even. Fine focus can be done on the front standard/lens, essentially how it's done on a real enlarger.

Below left is the negative sitting on a small LED light tablet. Below right is projection, over 16x20, on my utility door.

I did not want to hang the easel on the door, as this is just a test. So don't mind that the door is not a flat projection surface.

[Cor]

Assuming you have a darkroom I would suggest that you tape some pieces of B&W paper on the door and do some test strips to see if you get to decent exposure times at a descent F stop.

good luck !

Best,

Cor

[ic-racer]

Can you describe the process please? Thanks.

This is how I set the detents on the front standard of my view camera. (similar to enlarger alignment).

Bounce the laser off the shiny side of the ground glass. Usually this is from the back. Make a note of exactly where the beam falls, then take the back off and, with a microscope slide attached to the back element of the lens, adjust the front standard detents so the laser beam points to the same spot.

It is easier to attach the microscope slide to the front of the lens, so you can also flip the ground glass before you start and bounce off it with the lensboard removed, or maybe the dull side reflects the laser well enough too.