BESELER 45MX condensor placement

[Deryck]

Hi all,
A question concerning the stacking order of enlarger condensors.

I recently purchased from that big internet auction place a used 'BESELER 45MX' enlarger with the double condensor monochrome head. As the inside of the condensor housing had accumulated much dust, I stripped out the condensors and the heat absorbing glass for cleaning. On re-assembly of the unit I discovered that the condensor lenses are not identical, in that though the diameters are the same, one of the lenses is more convex than the other.
-one could say that one condensor is "thicker" than the other.

Could any of you 'BESELER 45' users out there please tell me whether the "thicker" condensor should be stacked on top of, or at the bottom of the condensor housing? Or, to put it another way: Should the "thicker" of the two condensors be closest to, or furthest from the negative carrier?

Thanks for your time,
Deryck

 

[optique]

I am away from my 45mxt, but couldn't you just assemble it one way, then check to see if the projected circle of light is correct? If not, then reverse them.

I recall that the final check was I had to test that the projected image circle was uniformly illuminated, and that it was big enough to contain the negative, once you insert the carrier. Otherwise, you may have vignetting or similar light falloff effects. This has more to do with adjusting the bellows compression (my term) than the condensors though.

You could also google for a scanned copy of the manual; I believe I found it that way.

Hope this helps.
steve.

 

[Konical]

Good Evening, Deryck,

I'm too lazy right now to go downstairs to the darkroom and dismantle my enlarger to check, but my memory is that the two condensers in the 45M are identical. My memory may well be faulty; could someone have possibly replaced one of your condensers with an ersatz item?

Konical

 

[Deryck]

Thanks for the quick response guys. I think I'll take Optiques' advice and try to find an instruction manual on this model. Other quirky things may present themselves as the 45M and I get down to brass tacks.

By the way Konical, how do you rate the 45M as a working machine? (I do mostly 4x5 stuff).

Thanks,
Deryck

 

[Konical]

Good Morning, Deryck,

I've had my 45 MCR-X since the mid-'70's. It's had moderate use on a fairly regular basis since then and has always performed flawlessly. My only regret is that it was expensive when I purchased it new; if only the current used darkroom market had been around back then!

For 4 x 5, keep the condensers just slightly above the indicator mark on the scale if you can do so without hurting light coverage. Any dust on the lower condenser may come partially into focus if the lower condenser is almost sitting on the negative, especially if you print at f11 or a smaller aperture.

Konical

 

[Deryck]

Thanks for the info Konical.

Cheers!

Deryck.

 

[Deryck]

Hi again Konical,

This morning I received the instruction manual I purchased for the 'BESELER 45MX' enlarger. Apart from mentioning that the condensers are 6½" in diameter, nothing is mentioned about any differences in the convex curves of the two condenser surfaces. However, the manual does state, and I quote: "THE UPPER AND LOWER CONDENSERS ARE NOT INTERCHANGEABLE". So I guess my original question still remains: Is the "THICKEST" of the two condensers closest to, or furthest from the negative stage?

Thanks for your time,
Deryck

 

[Konical]

Good Morning, Deryck,

Hmmm--If I ever knew that, I had forgotten. I've had my lenses out several times for cleaning. I hope I always returned them to their proper locations. I'll remember to double-check next time. Thanks for the reminder, but I can't answer your question. If each lens can physically fit into either position, I suppose one could just experiment to see about any difference in coverage or illumination evenness.

Konical

 

[Deryck]

Hi Konical,

I have sent an email to the manufacturers of 'BESELER' posing this question about the placement of the condensers. When/if I receive an answer I will let you know the correct stacking order of the condensers.

Best regards,
Deryck

 

[Papa Tango]

On both of my condenser heads one lens is plano-convex (one flat side, one curved side), and the other biconvex (two curved sides).

The plano-convex lens goes on the bottom of the condenser housing with the flat side toward the negative stage. The biconvex goes above it--there is no particular orientation of this lens as both convex curves are the same.

 

[Deryck]

Now I'm really confused!!! Are we still talking about the condensers in the 'BESELER 45MX' ? Both of my condenser lenses are plano-convex, though I guess you could say that one lens is more plano-convex = more curved on one side = thicker, than the other. The 'BESELER 45MX' manual clearly states that "the upper and lower condensers are NOT INTERCHANGEABLE" !!!

 

[Nicholas Lindan]

Beseler 45MXT manual, 590-01-04 Rev JX/1291.5SS (c~1991?)

"...the upper condenser is thinner than the lower condenser."

 

[Deryck]

Condenser Stacking Order

:confused:

 

[Deryck]

THANK YOU NICHOLAS, that answers my question exactly.

Cheers!
Deryck

 

[Deryck]

Hi,
Just for the record:
I recently received an email from 'BESELER' concerning the condensers in the 45M. The two condensers are NOT identical to each other. They are both 6½" in diameter, and are both plano-convex, but the "thicker" condenser is placed closest to the negative stage - as Nicholas previously informed us.¨

Deryck

 

[Konical]

Good Morning, Deryck,

Thanks for bringing this topic to our attention. I guess I have always replaced the lenses correctly after cleaning, but that was probably by accident. Sorry I can't recall where my Beseler 45 owners manual is located, so that I could have answered your question when you originally asked.

Konical

 

[xkaes]

I'm not dragging up this old thread because it might help someone with the same problem -- but that's a good enough reason.

Instead, I'm dragging it up because I have a related question.

As we all know, accurate, complete information on Beseler 4x5 enlargers is still hard to get. The best on-line source only lists limited info on three of Beseler's various configurations of 4x5 enlargers.

And although my question might seem simple, the answer might not be.

In the above discussion, the Beseler MX and the MXT are mentioned a lot. My enlarger -- the MXII -- is not. I know the difference between the MX and the MXT, but I don't know the differences between the MX and the MXII. All three apparently use the same condenser assembly -- let's call it the "MX condenser".

I know that some (all?) of the PRE-MX Beseler 45 enlargers used a different condenser assembly, are the MX condensers usable are the PRE-MX 45 enlargers?

This might help to answer the question. The diameter of the condensers on the MX enlargers is 6.5". Are they smaller on the PRE-MX enlargers?

 

[MattKing]

I'm not dragging up this old thread because it might help someone with the same problem -- but that's a good enough reason.

Instead, I'm dragging it up because I have a related question.

As we all know, accurate, complete information on Beseler 4x5 enlargers is still hard to get. The best on-line source only lists limited info on three of Beseler's various configurations of 4x5 enlargers.

And although my question might seem simple, the answer might not be.

In the above discussion, the Beseler MX and the MXT are mentioned a lot. My enlarger -- the MXII -- is not. I know the difference between the MX and the MXT, but I don't know the differences between the MX and the MXII. All three apparently use the same condenser assembly -- let's call it the "MX condenser".

I know that some (all?) of the PRE-MX Beseler 45 enlargers used a different condenser assembly, are the MX condensers usable are the PRE-MX 45 enlargers?

This might help to answer the question. The diameter of the condensers on the MX enlargers is 6.5". Are they smaller on the PRE-MX enlargers?

This seems like a great reason to start a new thread!
With a title like: "Beseler 4x5 enlargers - identifying the differences between models"

 

[Aidan Sciortino]

I have an MXII. My understanding is that the main thing that changed (until the release of the MXT) was the head the enlarger was packaged with, with minor adjustments to the motor assembly for raising and lowering said head.

I’ve got two condensers (up from none ) of different ages, both work fine. I think any condenser head should work fine as long as it covers 4x5 - it’s not like the mounting system on the head is very intricate anyways

 

[xkaes]

I'm wondering about the size and other possible changes. For example, the MX literature always refers to "over-sized" condensers, so I'm wondering if some (all?) earlier 45 models had smaller condensers. And some of the earlier models that I've seen (photos only) appear not to have a filter draw (which puts filter between the two condenser elements). So there are differences -- and someone out there must have (or used) the newest and older models -- and know the scoop, the skinny.

 

[xkaes]

With a title like: "Beseler 4x5 enlargers - identifying the differences between models"

Anyone interested in this rabbit hole?

 

[MattKing]

Anyone interested in this rabbit hole?

Start the thread, and it may turn into a valuable asset on Photrio!
Otherwise people who might be able to contribute but are only interested in Beselers with colour heads may never see your questions.

 

[xkaes]

Start the thread, and it may turn into a valuable asset on Photrio!

I certainly hope so. I'll add what I've got -- and I'm more than willing to permanently display the results on the SUBCLUB.

 

[mshchem]

Easy to adjust condensers if the little metal scale is present. The scale is removed to accommodate a dichroic head.

 

[Sundowner]

Anyone interested in this rabbit hole?

It would be helpful; I'm staring at a 45 condenser head right now that's not exactly corresponding to any of the previous descriptions...so a comprehensive what's-what thread would've been useful.