Need serious help! 4x5

jayvo86 · Jul 6, 2012

So I went to use my favorite enlarger today at the darkroom. (Omega Universal 4x5)

It's got a lens turret set up with a Rodagon 135mm 5.6 and a few other lenses.

I've always used it to enlarge big prints with my 35mm and medium format negs, but when I went to go enlarge my 4x5 negs (new to 4x5 btw) there was serious vignetting making the image unable to print.

It SEEMS like the lens doesn't cover the whole 4x5 negative. (You can see of the neg in the vignetting portion.)

The manager there says he is going to look into getting a "4x5" lens, but it seems strange that that lens doesn't work.

Anyone have a clue?

Thomas Bertilsson · Jul 6, 2012

Do you have the correct condenser (or condenser position) and/or bellows / lens cone?

removed-user-1 · Jul 6, 2012

Sounds like a condenser issue; the 135mm Rodagon should be fine for 4x5 printing. There should be a condenser lens in a housing above the negative stage, with a door that swings up so you can reposition the condenser. This door has a diagram on the inside that shows the position of the condenser for specific focal lengths.

jayvo86 · Jul 6, 2012

Thomas Bertilsson said:
Do you have the correct condenser (or condenser position) and/or bellows / lens cone?

I'm not sure.

The condenser covers the entire 4x5 neg, but there could be some fall off. I'm not sure about the bellows.

jayvo86 · Jul 6, 2012

rthomas said:
Sounds like a condenser issue; the 135mm Rodagon should be fine for 4x5 printing. There should be a condenser lens in a housing above the negative stage, with a door that swings up so you can reposition the condenser. This door has a diagram on the inside that shows the position of the condenser for specific focal lengths.

Let me see if I can find a manual.

Thomas Bertilsson · Jul 6, 2012

rthomas said:
Sounds like a condenser issue; the 135mm Rodagon should be fine for 4x5 printing. There should be a condenser lens in a housing above the negative stage, with a door that swings up so you can reposition the condenser. This door has a diagram on the inside that shows the position of the condenser for specific focal lengths.

That's very well explained.

jayvo86 · Jul 6, 2012

I pulled the condenser lenses out today and didn't see a whole lot. (Though, I didn't really know what I was looking for.)

I'll do some more digging tomorrow.

removed-user-1 · Jul 6, 2012

This is a diagram taken from the Omega D2 manual: View attachment 53491

I'm not certain this is what you have but as the diagram shows you want the condenser lens at the top of the housing for a 135mm lens. If you've been printing 35mm the condenser is probably at the bottom. Hope this helps!

David A. Goldfarb · Jul 6, 2012

I agree that it's a condenser issue. If you didn't have enough bellows or a long enough lens cone, you wouldn't be able to focus. A 135mm Rodagon should be able to cover 4x5". So the condensers need to be set to cover the full 4x5" neg.

jayvo86 · Jul 6, 2012

rthomas said:
This is a diagram taken from the Omega D2 manual: View attachment 53491

I'm not certain this is what you have but as the diagram shows you want the condenser lens at the top of the housing for a 135mm lens. If you've been printing 35mm the condenser is probably at the bottom. Hope this helps!

Ah! I remember seeing that. (upside down bowl.) If I remember correctly, it was pretty far down.

nworth · Jul 6, 2012

I've used the 135mm Rodagon for 4X5, and it works well. From what you say, a condenser problem is certainly possible, as discussed above. You also need to be aware that the turret places the lens further away from the negative and creates a little tunnel between the lens board and the rear element. Since 135mm is somewhat wide angle, this may be the problem if the condenser alignment doesn't cure the vignetting.

jayvo86 · Jul 6, 2012

nworth said:
I've used the 135mm Rodagon for 4X5, and it works well. From what you say, a condenser problem is certainly possible, as discussed above. You also need to be aware that the turret places the lens further away from the negative and creates a little tunnel between the lens board and the rear element. Since 135mm is somewhat wide angle, this may be the problem if the condenser alignment doesn't cure the vignetting.

They have a bunch of different stuff left over from when the darkroom was actually used.

If the turret creates a problem, I'll just swap it for a plain lens board.

Thomas Bertilsson · Jul 6, 2012

nworth said:
I've used the 135mm Rodagon for 4X5, and it works well. From what you say, a condenser problem is certainly possible, as discussed above. You also need to be aware that the turret places the lens further away from the negative and creates a little tunnel between the lens board and the rear element. Since 135mm is somewhat wide angle, this may be the problem if the condenser alignment doesn't cure the vignetting.

I believe the enlarger has an adjustable bellows, so this is a non-issue.

jayvo86 · Jul 6, 2012

Thomas Bertilsson said:
I believe the enlarger has an adjustable bellows, so this is a non-issue.

That's correct.

jayvo86 · Jul 7, 2012

rthomas said:
Sounds like a condenser issue; the 135mm Rodagon should be fine for 4x5 printing. There should be a condenser lens in a housing above the negative stage, with a door that swings up so you can reposition the condenser. This door has a diagram on the inside that shows the position of the condenser for specific focal lengths.

That was EXACTLY what the problem was!

Thanks for the help! Printing is good now!

-Josh

Need serious help! 4x5

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