Durst 609 Problem: Please help!

[thisispants]

Hi, So I've just bought a Durst 609. I'm very new to darkroom photography so I'm still learning the terms.

But.... I'm struggling with the focus.

I've got an 80mm lens in the enlarger, and the only way I can get a nicely focused image of the white eisel thing is if the enlarger head is relatively close to the base of the enlarger, giving me an image approximately 6 inches x 6 inches. If I move the enlarger head up to get a bigger enlargement, the focus knob fails to focus properly.

It's frustrating as I was hoping to get started enlarging straight away, but due to this problem I'm restricting my potential enlargement size. Quite frustrating.

Does anyone know what could cause this?

Mechanically everything appears to be working well. The focus knob moved the lens up and down. The enlarger head knob moves up and down.

I'm puzzled.

I'd really appreciate any thoughts or ideas as to the source of the problem.

Thanks in advance!

 

[thisispants]

Also, just for some more info, the 80mm lens is a componan schneider lens, and the lens board is essentially a metal disc. Is this unusual?

 

[Bob-D659]

What size is your negative? This isn't the problem, just needied for info to see if the 80mm lens is what you should be using.

Durst made recessed lens mounts, ixotub and siriotub, they come with different sized threaded holes to mount the lens. I think either will work for your 80mm lens.

 

[Роберт]

For 80mm you need a cone form type lens board. For 50mm it's normally a disc shape form.
So for the Schneider Companon 80mm lens you have the wrong lens board.

 

[thisispants]

Thanks for the information Bob. The negative is a 6x6, so an 80mm lens should be appropriate.
How to I accurately measure the lens size in mm.... in terms of thread. Tape measure?

Anyone else have any ideas.

The lens appears to be about 10cm from the lens when using the normal durst disc type lens mount I have.

Are there any other reason why focusing would be such a problem?

 

[Bob-D659]

Here is a link to the manual http://www.ph.utexas.edu/~yue/609/Durst609.html

It might help you, as it shows the standard lens mount setup. If yours looks different, that will be a clue as to the problem.

Edit, yes, the manual recommends a recessed lens mount for a 75mm lens, you will need one for the 80mm lens.