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BEOON - enlarger lenses to avoid / recommended (Open thread - please add your experience for benefit of others)


Steve Ricoh

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I wish a thread like this existed before my purchase of an El-Nikkor 50mm f/2.8

 

Do NOT waste your time or money purchasing an El-Nikkor 50mm f/2.8, it does not work at 1:1 with any combination of extension tube supplied with the BEOON. With a FF M240 attached, the column height runs out of adjustment, bottoming at minimum height whilst still being approx 10mm too high.

 

For the benefit of other members, please add your experience of using different makes of enlarger lenses.

 

(I suggest a comment quantifying the availability of column adjustment BELOW critical focus, as most people find the ability to hunt arround critical focus to be of great benefit.)

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Steve,

I'm currently out of town, well out of town.

My recollection though was that my Apo Rodagon 50mm worked OK, but I was using a Fuji X camera (so APS).

The other thought though, surely the El-Nikkor will be the same as most any other enlarging lens, back focus wise?

Gary

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Steve,

 

This thread is an excellent idea. Since the distance between the nodal point of an enlarging lens and the mounting flange is not standardized, and is not published as far as I know, the necessary length of extension tubes for a given reproduction ratio with a given enlarging lens and a given sensor size can not determined analytically. It can only be determined empirically, i.e., by trial and error.

 

I will measure the available focusing range of both of my BEOON setups - 35mm and MF - when I get home from church where I will be praying for friends and family in the path of Hurricane Irma.

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Here are the two setups I use for digitizing negatives with the BEOON. The 35mm setup fills the frame of the APS sensor with the image of a 35mm negative. The MF setup fills the height of the sensor with the image of a Rolleiflex F2.8 negative. A Hasselblad negative is significantly smaller so the "scan" includes a heavy black border.

 

35mm setup:

  - Fuji X-T20 camera

  - 2.8/50 Schneider Componon-S enlarging lens

  - 40mm extension tube

I can lower the assembly about 5/8" below the focus point and raise it several inches above the focus point.

 

MF setup:

  - Fuji X-T20 camera

  - 40/4 El Nikkor enlarging lens

  - Extension tube C supplied with BEOON

I can lower the assembly about 2" below the focus point and raise it more than 2" above the focus point.

 

There is probably no need to repeat the obvious, but just in case...  These setups use an APSC camera. They will not work with a full frame camera.

Edited by Doug A
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Steve: Pardon my ignorance, but would a 10mm extension tube do the trick, or does the column need to be shortened.

It might take both: an extension tube to reach the proper extension and a shorter column to bring the slide into focus.

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Steve: Pardon my ignorance, but would a 10mm extension tube do the trick, or does the column need to be shortened.

Using the Nikkor 50 f/1.4 and tubes B+C+D, the column bottoms prior to focus. If I lift the negative by 10mm (approx) I can then focus adequately. Removing tube C (which is 17.14mm) I can focus with plenty of adjustment on the column , but not at 1:1. Bizarrely, others report success with BCD tubes whilst using a Focotar-2 50 f/4.5. I suspect the Focotar has a shorter focal length than the Nikkor, that's the only logical explanation in my view.

Edited by Steve Ricoh
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Well, just by curiosity, yesterday I took out EL-Nikkor N 2.8/50 and mount it on a bellow and figure out to reach 1:1 (without Beoon of course) with a slide Pentax duplicator.

So about 65mm of bellow from M flange to lens flange to have 1:1.

Distance from M flange to slide is about 165mm in this case 1:1.

 

Then on my Beoon, the shortest distance from M mount flange to 1:1 mask is about 172mm.

So in best case to reach 1:1 the film must be focused (placed) about 172 - 165 = 7mm nearer than the 1:1 mask plane with EL-Nikkor N 2.8/50.

 

Thing that I have done already in the past with "about 1cm thick material" to raise the slide when I used the EL- Nikkor N 50mm with Beoon.

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Bizarrely, others report success with BCD tubes whilst using a Focotar-2 50 f/4.5. I suspect the Focotar has a shorter focal length than the Nikkor,

 

The Focotar might have a different nodal point. In my experience I find it to be a poor enlarging lens. In fact, all the Focotars are deficient, but they still might be good close-up lenses. I've never used them as such.

Edited by pico
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The entire K-64 slide captured with the BEOON using a Sony A7, 50mm 2.8 APO-Rodagon with the B,C and D tubes. I was able to successfully use a Fuji X-E2 (cannot remember which tubes I used), but found the Sony easier to focus and less fiddly than the Fuji. 

 

DSC00122.jpg

@Jim. May I ask your opinion of the IQ and colour rendition of the Sony A7 compared to the Fuji XE-2? I'm considering purchasing an A7 as a full frame. I'm happy with my XT-1 but we're always curious eh?

 

Thanks in advance

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@Reeray I found the A7 were more neutral. The link below is to the RAW files of a K-64 image made with both cameras. Same lightbox used for both images so a pretty good apples-to-apples comparison. I thought the Fuji might be better since I'm not using the entire image circle but I didn't see any benefit to APS-C over FF.

 

In the end the A7 won out for the ability to mount so many old MF lenses on it and still be the same focal length. I didn't expect this. I soon dumped my Fuji X100T in favor of the A7. I found it a nice companion/backup to an M body.

 

https://www.dropbox.com/sh/mga67pb3fyunbwg/AACZXEmIroP07geZ66nR0RUNa?dl=0

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Well, just by curiosity, yesterday I took out EL-Nikkor N 2.8/50 and mount it on a bellow and figure out to reach 1:1 (without Beoon of course) with a slide Pentax duplicator.

So about 65mm of bellow from M flange to lens flange to have 1:1.

Distance from M flange to slide is about 165mm in this case 1:1.

 

Then on my Beoon, the shortest distance from M mount flange to 1:1 mask is about 172mm.

So in best case to reach 1:1 the film must be focused (placed) about 172 - 165 = 7mm nearer than the 1:1 mask plane with EL-Nikkor N 2.8/50.

 

Thing that I have done already in the past with "about 1cm thick material" to raise the slide when I used the EL- Nikkor N 50mm with Beoon.

On Saturday, in total frustration, I quickly measured the height by which I would need to raise the negative and worked it out to be 9mm, so I wasn't far off your more precise measurements.

What did you use to make the 1cm thick material? Presumably black and non reflective, and how did you hold the negative in place, using the 1:1 BEOON slide, or by other means? (A picture of the set up you used would be handy - if you still have it).

I won't be rushing out to buy another enlarger lens until I have complete grasp of the underlying optical considerations, but as Doug A stated above, it's more empirical than analytical, we'll certainly for me. I did basic optics at A level, but that was a long long time ago.

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Steve, the spacer was empirical and I used something handy-to-try.

I used as "spacer" screw in 49mm Pentax Standard lens hood (or Minolta MD 28/2  hood a bit shorter) put on the light table without 1:1 mask.

Really tricky to position slide and much flare : so why I gave up at that time.

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Steve, the spacer was empirical and I used something handy-to-try.

I used as "spacer" screw in 49mm Pentax Standard lens hood (or Minolta MD 28/2  hood a bit shorter) put on the light table without 1:1 mask.

Really tricky to position slide and much flare : so why I gave up at that time.

Yes I see your point, I think I'll abandon the idea.

I'm wondering about a shorter tube replacing C (17.14mm: pop's measurement), however this is all empirical 'playing' that will definitely lead to more expense, but without much gain (I realise I won't get 1:1 but 1.1:1 would be good on a 24MP camera). Without knowing the nodal point of the Nikkor, it's merely guesswork on my part.

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Is there anyone with experience of using the Shneider Componon-S 50 f/2.8 on the BEOON, and if so how much column adjustment remains once critical focus is nailed. In my mind it's important to be able defocus either side of critical focus - running out of column adjustment to make the assembly shorter is a non-starter.

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I use this lens as follows.

 

My Beoon Set Up

 

35mm with APS-C and Componon S 50mm - 3rd party 40mm tube

120 with APS-C and Rodagon WA 40mm - 2 small tubes total 12mm (just because I have them. A single 12mm would do)

120 with FF and Componon S 50mm - as above small tubes and Beoon C tube

35mm with FF and 50mm Componon S - Beoon tubes B+C+D

 

In all instances I have more than enough adjustment available for critical focus with lots in hand to de-focus either way.

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Steve,

 

Eureka !

 

After trying combinaisons of rings of what I have.

I've found what you can use now with what you have if you accept "only 12 Mpix" file (good enough for negative for me, see grain of film).

 

Just try without ring C.

 

M240 + Beoon + B + D + EL-Nikkor N 2.8/50 and 1:1 mask.

Negative under the mask and I focus with small margin but with large waste of field.

 

In PP if only negativ surface keeping, remain about 12 Mpix of 24 M.

You can try that to begin with what you have now.

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