Aligning Omega D5 and Beseler 4x5

[ic-racer]

You can calculate the focal depth on the baseboard side with an equation similar to the view camera focusing equation.

For most apertures and magnifications the focus spread is in the millimeter to centimeter range. Thus, as I indicated the lens-film alignment is what is crucial. The baseboard alignment is less critical. Enlarger manufactures understand this and design accordingly.

[SamReeves]

The D-5 is a tricky one. After much consternation, I decided to level off the baseboard first by shimming up the corners. Once that was done, the alignment of the negative stage and lens stage went a lot smoother.

[neil poulsen]

Thanks to everyone for their comments. I will try to incorporate ideas that have been offered.

It's amazing to me that after decades of producing these enlargers, neither company progressed to a versions where these crucial alignments could be something different than makeshift.

In my view, both the negative stage and the lens stage should be adjustable in both axes.

[neil poulsen]

. . . A properly aligned enlarger has the negative, lens and paper planes all properly aligned. You don't want to rely on an unaligned baseboard if you want the optimal performance from your image and lens. They are a chain and relying on depth of field or depth of focus in lieu of proper alignment will give you less the optimal performance. So will the lack of a glass carrier. And if you are printing glassless then the requirement for proper alignment is far less important as you can not get optimal performance from an enlarging lens without a glass carrier.

Thanks Bob. Very good points here.

[neil poulsen]

Which model 4x5 Beseler were you using? The latest, and I guess final, Beseler is the MXT which I used for about 10 years. I don't remember the details but Beseler improved the alignment system on the MXT in some manner or fashion as compared with earlier models.

We have the MXT. It's black, versus the blue color of earlier models. Maybe there's something I can do to improve the alignment. For example, by my inspection, the negative stage is completely rigid to the rest of the chassis. But, maybe there's an adjustment that I've missed.

[lloyd]

I've ordered a Delta 4x4" Bes-Align board from B&H yesterday. If this works, and I suspect it will, then I will take the Beseler board on which I have mounted a Schneider 180mm Componon-S to a machine shop to have the 3 adjustment screws installed.

This is what I've done; I believe this design originated with Zone VI, and it works v. well.

[Nathan Potter]

Enlargers are like view cameras but without much in the way of adjustments so I share Neils frustrations. There are three planes that really should be exactly parallel - the film, the lens and the baseboard (easel). Only two of the planes need tilt adjustment to match the third so pick the two easiest to adjust. The other desirable adjustment but less critical is to align the optical axis of the lens to the center of the film. That depends on the coverage of the lens to the size of the film.

The other frustration can be the flex inherent in the mechanical parts of most enlargers. Flex in the whole head relative to the baseboard bugs me but flex between the lens and film holder can also occur during repeated exchanging of film holder over time.

I tend to use thin shims with sticky tape for film and lens plane adjustment and leveling screws for baseboard adjustment. An optical collimator is the ideal readout mechanism for planarity adjustments but I scavenged a couple old of IC glass photomasks with chrome emulsions which are a good substitute but you need to work with the enlarger lens wide open for alignment.

Nate Potter, Austin TX.

[tgtaylor]

We have the MXT. It's black, versus the blue color of earlier models. Maybe there's something I can do to improve the alignment. For example, by my inspection, the negative stage is completely rigid to the rest of the chassis. But, maybe there's an adjustment that I've missed.

Yeah, you missed it! FWIW, pick-up a Beseler MXT manual - you can readily find them on E-bay for ~$10. Except for the lens stage, the manual gives detailed instructions on aligning the enlarger. You'll need 2 wrenches: 11mm and 14mm. As far as the lens stage, if you have the new Beseler lens boards with the 2 locking screws you can fiddle with them and, if everything else is level and the chassis is not warped, you can probably bring the alignment into about 1/16.”

[Dave Langendonk]

From my perspective on the D5 Omega, it's not possible to adjust the lens-stage along either the Y or Z axis without trying to change the angle of the entire enlarger. Moreover, if the Y axis at the lens stage isn't parallel to the Y axis at the negative stage, it's too bad Charlie! For example, the only adjustment for the negative stage is along the Z axis.

Neil,

On the Omega, the lens stage is adjusted by means of an eccentric rod on the carriage that rides along the column. This allows front to back alignment of the lens stage to the baseboard without using shims. Once the Lens stage is parallel with the baseboard, the negative stage can be aligned as mentioned above. I have a service manual I'd be happy to email you if you're interested. Just PM me your email address.

[Brian Ellis]

Which model Beseler were you using? Beseler made some changes with the MXT that improved the ease of aligning it. I don't now remember what the changes were but I know it wasn't terribly difficult to align my MXT.