# Lens and Lensboard



## mangorockfish (Feb 16, 2018)

Setting up my old darkroom in the near future for b&w developing and printing and need a lens and lensboard  for my Bessler 23C enlarger.  I have always printed 35mm in the past, but am now shooting a 645 camera and have no idea what mm lens I need and what board and negative carrier.  Can someone please help me out here?  Thanks


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## compur (Feb 17, 2018)

You'll need a 75mm enlarger lens. You could also use a longer lens, say, 80-105mm. Lens board is the standard 23C board. Get one with matching hole size that fits the lens. Usually either 25mm or 39mm in diameter. If you already have a board for printing 35mm negs you can use that if the hole size matches your new lens.  You'll also need a threaded retaining ring to fix the lens to the board. This usually comes with the lens. And, a 23C negative carrier for 645 negatives.


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## mangorockfish (Feb 17, 2018)

Compur, Thank you very much for the info, just what I was looking for.  It's been about 40 years since I've done any darkroom work and have forgotten a lot.


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## ac12 (Feb 17, 2018)

With the good lenses out there now, get a 39mm lens board and lenses.
I would not bother with the 25mm lenses.

General guideline is the enlarger lens is the same as the normal lens for that format.
- 35mm film = 50mm lens
- 6x6 film = 80mm lens
- 4x5 sheet film = 135 or 150mm lens

However, if you want to make a smaller print, having a longer lens is convenient.  I have many times used a  75 or 80mm lens for 35mm film, so I would not have the head so far down to the baseboard that it gets in the way of using the easel.


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## compur (Feb 17, 2018)

There is a very good darkroom book offered free by the author which contains a chart showing the results of the most expensive tests of enlarging lenses ever done. It can be legally downloaded here:
Ctein Online-- Post Exposure Sample


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## webestang64 (Feb 18, 2018)

All my enlarging lenses are Rodenstock. I swear by them having printed in the darkroom professionally for over 35 years.


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## ac12 (Feb 18, 2018)

I think the big 3 names (in alpha order) and lens line are:

Nikon, El Nikkor
Rodenstock, Rodagon
Schneider, Componon-S
There are other brands with excellent lenses also.

From my old notes, I would look for a later 6-element lens.
Example, El Nikkor 50/2.8 rather than the 50/4.


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