Question Regarding Omega Super Chromega D Dichroic II

[cargosteve]

Anyone know the maximum printing size for 4x5 you can make with this enlarger? (Either with 135mm or 150mm)

[Jochen_S]

Might depend on how you mount it. Mine came with wall mounting. Projecting on the floor, I can crop quite a lot on a 50x70cm sheet. Is your building antique and your ceiling higher? Are you planning giant prints on irregular paper stock? 

[AJG]

My ancient Omega D-2 would make a 16x20 on the baseboard with a 150 mm lens.  It was possible to rotate the enlarger column and project on the floor for larger prints with lots of counterweight on the baseboard.

[cargosteve]

5 hours ago, Jochen1664876637 said:

Is your building antique and your ceiling higher? Are you planning giant prints on irregular paper stock?

Wouldn't say antique, I'm working out of the bathroom in my apartment but I've got decent space in there. Hoping to print up to 20x24" with this enlarger. Not sure if that qualifies as irregular paper stock.

3 hours ago, AJG said:

It was possible to rotate the enlarger column and project on the floor for larger prints with lots of counterweight on the baseboard.

Interesting, didn't realize the unit could do that. Might open up a whole lot more possibilities!

 

Thank you both!

[GlennS]

I’ve got the dichroic D6-XL,  With the head at maximum height 50” above baseboard I get a ~ 30”x24” image with a 150mm lens on 4x5”. A 135mm would better if going big  

Have never printed larger than 16x20” but have heard of people using front surface mirrors to project the image horizontally for huge prints..  The 50” mentioned above is the distance from baseboard to negative. 
 

 

[bob_salomon]

The 120mm wa would give you even bigger prints vertically.

[john_cooper9]

When I was young, about 10, my friend and me put the enlarger at the top of the stairs and projected a picture of an ant onto POP paper. It was 35mm but you could try it with 4x5. Luckily there was no adult to point out how ridiculous this was. And it was a dark and stormy night and the parents had gone out.

[rodeo_joe1]

A bit of measurement and maths give a close approximation to what magnification you'll get with a given column-height and lens. 

Measure the distance from the easel surface to the film stage of the enlarger at the top of the column (preferrably in mm). Divide that distance by the focal-length of the lens and subtract 2. Then you have approximately the maximum magnification you can get out of the enlarger. 

Example: If we do the maths on GlennS's example 50" head height (= 1270mm) and divide it by 150 we get 8.47. Take away 2 and that leaves 6.47.

6.47 * 4" x 5" = (just over) 25" x 32"

Which is close enough to what Glenn finds in practice.

As a formula we can express it as:

M = (d/f) - 2

This only works for quite big magnifications though. A more accurate formula is a bit more complicated. 

Edited November 10, 2022 by rodeo_joe1

[Monophoto]

On 10/31/2022 at 8:26 PM, Jochen1664876637 said:

Might depend on how you mount it. Mine came with wall mounting. Projecting on the floor, I can crop quite a lot on a 50x70cm sheet. Is your building antique and your ceiling higher? Are you planning giant prints on irregular paper stock? 

Clearly.

When I built the darkroom in our former home, my enlarger was a Durst F60.  To get additional enlargement capability, I  attached a shallow shelf to the wall at my enlarging station, and the designed the counter below the enlarger such that the top could be lowered in 6" increments below the nominal counter top level.  With this arrangement, printing 11x14 was a snap, and I could easily get to 16x20 with a little effort.

Later, I bought a DII that came without a baseboard.  I attached it to the same shelf (with some additional reinforcement of course).