Durst L1200 alignment problem

Hello all,
I've been reading these great forums for serveral month now and learned a ton from it so let me first say a big "Thanks" to all contributors. But now I encounter some strange problem with my Durst L1200 that wasn't mentioned anywhere.
It just went out of alignment from one print to another. I haven't even touched it, just used a bigger paper to make the final print instead of a test. The test-print is razor sharp where the final one already gets softer. The paper is held absoluteley flat and I even can see slight traces of softness by the naked eye on all of my easels.

How is it possible for this giant piece of metal to go out of alignment in a second by itself after many month of troublefree use? And, most important, how do I prevent this from happening again? I don't own one, but I'm quite sure that the manual won't contain information about my problem.
I guess I have to buy a Versalab laser now. Silly me not to buy that 138S for 200€. Now I see the disadvantages of having only one enlarger and a nearly 6 cm high "mountain" of negs to do.

thanks in advance
Clemens Bauer

Can you fix it by refocusing? Does it get better if you stop down the lens? Could it be that the spring on the lower focusing knob needs retensioning? Certainly there is not an alignment problem, especially not one that occurs suddenly without particular motivation.

Clemens,

How is the enlarger mounted? To a baseboard, to the wall? I have an L1200 and a Versalab. I also have the manual to the L1200, I am running it with the Multigraph head. It is not that tough to un-align the L1200. But it’s also easy to re-align one.

How can I be of assistance to you?

Pete Dendrinos

It sounds to me more like the negative "popped" from the heat of the lamp. If so you should try to tape the negative to the holder. Strech it out and tape the sides.

How about more details?

Len mounting plate? Which lamp system? How dense are the negatives? What size of print are you doing? How long are the typical exposures. Ambient temperature? Any motors, dryers, washing machines, air coditioners cycling? Is the floor solid? Is the paper held down? Humidity may curl paper not "held" in place. Frozen paper used sans allowing to come to room temperature.

Is the entire area of the print soft, or is some line across the print OK?

One thing to check are two controls that allow the head and the lens stage to rotate. The head rotates in case you want to project on the wall. There is a lock for this and also a pin for the vertical and 90 degree positions. The lens stage rotates to use the Scheimpflug effect if you are using a tilted head or easel to correct perspective. If this motion isn't locked it can rotate easily and would throw off the focus across most of the area of the print. Just a guess -- this is one way that I can think of for a L1200 to suddenly become misaligned.

Farmer said:

Hello all,
I've been reading these great forums for serveral month now and learned a ton from it so let me first say a big "Thanks" to all contributors. But now I encounter some strange problem with my Durst L1200 that wasn't mentioned anywhere.
It just went out of alignment from one print to another. I haven't even touched it, just used a bigger paper to make the final print instead of a test. The test-print is razor sharp where the final one already gets softer.

Click to expand...

I doubt it went out of alignment but rather it sounds like your head is slipping--- not unknown to worn commerical or unserviced enlargers. You may want to clean the column and fitaments and use a thin bit of appropriate (synthetic) lubricant.

Len mounting plate? Which lamp system? How dense are the negatives? What size of print are you doing? How long are the typical exposures. Ambient temperature? Any motors, dryers, washing machines, air coditioners cycling? Is the floor solid? Is the paper held down? Is the floor solid? Is the paper held down?

Click to expand...

I'm using a 80mm f/5,6 EL Nikkor at f/11 in a Lapla 39. I exchanged plates and couldn't see any effect at all. I enlarge to 9x12".
The head is a CLS 450.
Exposure times are in the 60 second range when not split grade printing. The negatives print without any problems in terms of tonal reproduction, they show good but not excessiv contrast and density. Due to the lack of a densidometer I can't take any measurements.
Ambient temperature is 19°C, varies about 1° during the day. Humidity is around 40%. There were no electrical devices running besides a Durst Sanat and a small router.
The floor is very solid, it's the basement made of more than 1 meter concrete and steel.
Paper flatness is very good, I used an electro-static easel at maximum power for testing.

Since the "normal" 4x5' negative stage wasn't supplied I have to use the smaller Bimaboxes and a Bimaneg carrier.

It sounds to me more like the negative "popped" from the heat of the lamp. If so you should try to tape the negative to the holder. Strech it out and tape the sides.

Click to expand...

I tried many different negatives and a glass carrier, everything looks the same.

How is the enlarger mounted? To a baseboard, to the wall? I have an L1200 and a Versalab. I also have the manual to the L1200, I am running it with the Multigraph head. It is not that tough to un-align the L1200. But it’s also easy to re-align one.
How can I be of assistance to you?

Click to expand...

It's mounted to the original Durst baseboard. The desk it stands on isn't the best on earth but reasonably solid.
Do you know if it's possible for the zero detents of the Scheimpflug controls to become misaligned?

Is the entire area of the print soft, or is some line across the print OK?

Click to expand...

When the lower left corner is in focus, the right one goes noticable softer. There's also a drop in sharpness from bottom to top too but not that much. It seems to have tilted forwards/left since this edge is the nearest one to the negative. I haven't touched the Scheimpflug controls for several weeks when I played around with wall projection.

Farmer said:

It's mounted to the original Durst baseboard. The desk it stands on isn't the best on earth but reasonably solid.
Do you know if it's possible for the zero detents of the Scheimpflug controls to become misaligned?

Click to expand...

I would not trust the detents as a true reference point!! It's most likely that you have inadvertently moved the head out of alignment. I would also check the mounting bolts just to be sure the column is still tight to the baseboard.

An alignment tool is a must in my opinion. And as an aside it's worth noting that the adjustments on the enlarger can not correct out every plane. You will need to use shims. I use strips if sheet film. At the top of the column, I put a turnbuckle, to aid in adjustment.

Pete

Turn-buckle with image a real plus, thanks.