Advice on 8 x 10" Durst Enlarger/Focusing

[jimsienkiewicz]

Hi everyone. I have an 8 x 10" Durst Laborator enlarger and there has been some difficulty related to focusing 8 x 10" negatives for projection using the vertical alignment of the enlarger. I can focus and produce prints in the 11 x 14" - 16 x 20" size no problem from 120 sized negatives as well as 4 x 5" but for the life of me I cannot focus the 8 x 10" negatives. Ideally I would be printing 16 x 20"s from this size negative.

I am using the standard 300mm lens and the Lacon 380 top and bottom condensers which are the correct pieces of equipment for this negative format. I have tried all the tricks related to making the enlarger height go up and down as well as the bellows and focus. I can get about 65" between the base board and the lens, which I believe is enough height to at least make the 11 x 14"s from the 8 x 10" negs. Does anyone know any tricks or other things to attempt that I am missing? Any information would be extremely valuable.

Thanks,

Jim

 

[Bob-D659]

Sounds like you can't get the lens far enough away from the negative. An 11x14 print from a 4x5 neg is a 3x enlargement, not much really. A 3x from an 8x10 neg is a 24x30 print. For an 11x14 print, you are trying to do only a 1.5x enlargement, that has the lens a long ways from the neg. Can you do a 6x7.5" print from a 4x5 neg?

 

[ic-racer]

No 'tricks' needed.

I just did some 16x20s with one-inch border last night. Negative is 51" from the baseboard and the lensboard is 36" from the baseboard. Going by the millimeter markers on the column, the baseboard is at 250mm and the head is at 1305mm (L1840, 300mm lens).

Try setting up your enlarger with those settings and you should be very close to where you want to be.

If it is still not right, post a picture of your setup.

You should be able to do 40" prints in the vertical position with that enlarger. If you can't, its like having a Ferrari and only being able to go 35mph

 

[bill@lapetelabs.com]

Jim, my Durst 184 chart recommends a LACON 380 / LACON 382 (V) for 1.2 x to 2.4 x magnification and a LACON 380 / LACON 380 (V) for 2.4 x to 3.9 x magnification. that is for a 300mm (12") lens, vertical projection! With a over (flat top) / under (flat bottom) arraingement of the condensors. We use that set up to print enlarged contact sheets up to 20x24.

 

[jerry lebens]

Perhaps you have the (fairly rare) perspective correction type baseboard fitted to your enlarger? I had to remove it on my Laborator in order to achieve the correct focussing distances for 10x8 negs.

Apart from that, it's quite easy to miss the point when focus has been achieved. It's easy to go straight past it by mistake - it takes some practice to get right...

Regards
Jerry