35mm wide angle enlarging lenses for UV?

[Mark Jones]

So everyone knows the 35mm f/3.5 old camera lenses are good for uv, but there are several 35mm 3.5 enlarging lenses that I have not seen mentioned or tested.

There is a really small cheap looking one with a 1cm front element made by Beslar, vivitar and other brands, looks uncoated and maybe 3 elements.

Alos Have a rodenstock eurygon 35mm f/4 lens, but it does not have a 39mm mounting thread, maybe 40mm? Just a little bigger.

Waiting on some chinese M39 helicoids so I can mount these on my mirror less camera.

 

These are only useful on mirrorless cameras or if used on a dslr for very close macro work. Probabaly why there is little mention of them.

 

https://www.ebay.com/sch/i.html?_from=R40&_nkw=35mm+enlarging+lens+-50mm&_sacat=0&_sop=15

 

the vivitar and beslar ones probably came on cheap entry level darkroom enlargers and sell for about $20.

[Andy Perrin]

You can always try them and tell us. That is how we know about all the others!

[enricosavazzi]

There is an El Nikkor 40 mm f/4 that I tested several years ago:

 

http://www.savazzi.net/photography/el-nikkor_uv.htm

 

This tested roughly the same as other El Nikkors, though with a relatively low contrast and not as good in UV as the 80 mm and 105 mm.

 

Cooke triplets and comparable optical schemes are likely to have a relatively good UV transmission, but their image circle and overall image quality are limited, especially at short focal lengths. They may be worth testing if you happen to own some, but I should not expect particular advantages of these enlarger lenses over the 35 mm camera lenses we already know (and the disadvantage of having to provide a separate focusing helicoid). Full-spectrum converted mirrorless full-frame cameras are getting relatively common, so these enlarger lenses are now potentially more usable than in the past.

[Andy Perrin]

We really have a glut of those 35/3.5's though, so if you happen to have other focal lengths, those would be more valuable to know about if they have good UV transmission and are good lenses. One of the reasons the EL-Nikkor 80mm/5.6 metal version is so popular is that not only does it have a good transmission, it's also a very sharp lens without much chromatic aberration. I have a number of 35/3.5 lenses that transmit well, but are very fuzzy and low contrast. I don't use them very much.

[ulf]

For full frame cameras wide lenses have a potential problem with dichroic filters like the Baader U https://www.baader-planetarium.com/en/filters/baader-u-filter-(venus-and-uv---350nm).html

and StraightEdgeU http://www.uvroptics.com/index.php?SEUGen3

Dichroic filters change their characteristics by the field angle. A 35mm lens might be showing this slightly even on an APS-C camera.

[Andy Perrin]

Ulf, true, but it's easy enough to just use filter glass. That's what I use for nearly everything anyhow, because of that problem.

[Timber]

I had a Soligor 35mm f3.5 enlarger lens and it works fine, but only on APS-C or smaller. Already vignetting on APS-C.

[Andrea B.]

One problem I've found with enlarger lenses is that many do not have front threading which permits filters or step rings. I do like the enlarger lenses I've tested though.

[eye4invisible]

These are only useful on mirrorless cameras or if used on a dslr for very close macro work.

Not quite.

 

All of my enlargers have long FFDs, easily working as macro and can reach infinity focus on my Nikon D3200:

EL-Nikkor 80㎜ ƒ/5.6

Wollensak Raptar 182㎜ ƒ/4.5 (ridiculously long FFD - need a 35-90mm helicoid almost fully extended on my DSLR, too long for my Sony mirrorless)

Schneider-Kreuchnach Componar 75㎜ ƒ/4.5 (square aperture blades)

PZO Emitar 80㎜ ƒ/4.5

 

Of course, these are all at longer focal lengths, but focal length and FFD are not related. There's no reason why a 35㎜ enlarger wouldn't work as a non-macro lens on a DSLR.

 

What is definitely a mixed bag, are projection lenses. Some of my projection lenses have very short FFDs. For example, I won't be able to use my Meopta Meostigmat 50㎜ ƒ/1.0 on my A7 until I can find a place that can mill down the rear of the lens barrel.

[ulf]

Of course, these are all at longer focal lengths, but focal length and FFD are not related.

 

I beg to differ.

At least down to 50mm focal length, all my different enlarger lenses, 50mm-240mm, tend to get a shorter front flange distance when the focal length decrease.

This is especially true for the rather symmetrical designs often used in enlarger and copy lenses.

My 50mm Focotars can just barely reach infinity if mounted directly on the M30 to EOS lens mount adapter.

 

I must admit that I have never tried anything shorter than 50mm, but think it is unlikely that there are any enlarger lenses with retro-focus designs, increasing the register.

[ulf]

Ulf, true, but it's easy enough to just use filter glass. That's what I use for nearly everything anyhow, because of that problem.

So do I.

I just wanted to point out the drawback of combining wide angle with dichroic filters.

[Mark Jones]

I was planning on getting the Baudder Venus UV filter 1.25" size and putting it inside the camera, I think Bjorn said it was better there and helped with reducing optical issues.

 

Once I get all the adapters to mount I will make some tests. I've ordered some helicals to mount them to my canon M3. I'm happy to report that its much easier to get helicals now then it was several years ago.

most of these 35mm enlarger lenses need about 20mm space between the eosM moutn and the rear of the lens. Pretty much perfect for a helical to go inbetween.

 

I have to figure some way to mount the 40mm rear thread Rodenstock lens too. Maybe I'll drill out a standard M39 adapter and put a 40 to 42mm step down ring on the back as a nut. It has a lot of blueish and purple looking Ar coatings. I am assuming that is bad news for UV transmission.

[Andy Perrin]

Mark, trying to rear-mount a Baader is doable but it limits your ability to change filters on the fly, like if you want to switch from UV to visible (which we often do). It DOES help with the dichroic color change issue that Ulf mentioned, but you can also just use filter glass on the front to fix that. Birna (Bjorn is not her name now) has multiple converted camera bodies and can do things like rear-mount Baader filters. If you have multiple converted camera bodies you can take that approach, but I don't recommend it if you only have one!

[ulf]

Mark, I second what Andy is saying.

 

It is often practical to be able to use other filters too, at least to be able to make a VIS reference-image to compare to the UV-image.

I switch between many filters and even if I have a Baader U, it is rarely used.

[JCDowdy]

You might find this interesting:

 

LENSES: WHAT’S IN A BRAND (35MM F3.5 ENLARGER LENSES)?

Boon Tang, 22 SEPTEMBER, 2014

[Timber]

I beg to differ.

At least down to 50mm focal length, all my different enlarger lenses, 50mm-240mm, tend to get a shorter front flange distance when the focal length decrease.

This is especially true for the rather symmetrical designs often used in enlarger and copy lenses.

My 50mm Focotars can just barely reach infinity if mounted directly on the M30 to EOS lens mount adapter.

 

I must admit that I have never tried anything shorter than 50mm, but think it is unlikely that there are any enlarger lenses with retro-focus designs, increasing the register.

I can second that... It seems to me that focal length and FFD seems to be nearly the same for enlarger lenses I have, but definitely as the FL increases so does the FFD.

[Andrea B.]

Checked my enlargers which here listed in increasing FFD order.

The ~ symbol indicates that I measured FFD myself because I could not find an FFD source for that enlarger. Those FFDs might not be exact but they are close enough for the practical purposes of mounting the enlarger on a helicoid and attaining infinity focus.

 

There is one outlier with the UV-Rodagon.

And note that the two 63 mm enlargers have two different focal lengths.

So there is some dependency on how the list is sorted.

Same thing with the two 75 mm enlargers.

 

IF the two T2 mount enlargers were not considered, THEN the UV-Planar would be the outlier.

 

I think the statement is generally true that increasing focal length implies increasing FFD if you sort in a certain way.

 

All that is slightly confusing. I am *not* a good data analyst. Oh well.

 

[Andrea B.]

If I interpolate, then that Omegaron has an FFD between 36.6 - 43.75 mm depending on which lines are used. That does give me something to go on for determining how to use the Omegaron. It is not a good fit for the Pentax or the Nikons. Must use it on the Lumix or Sony *if* I want long focus.

[ulf]

Is long focus distances a really good idea for these type of lenses?

Often they are optically optimised for the rather short distances normally found in enlargers.

Some of them might be acceptable for long focus distances, but not all.

 

This is the same phenomenon that give the recommendation to reverse mount normal lenses when using them for closeup macro > 1:1

[Andy Perrin]

I plotted every non-dedicated UV lens in the sticky that had an FFD listed. In the case of ones with multiple FFDs, if they were the same, only one is plotted, if they were different by more than 1 mm, both are on here.

 

What became obvious from the plot (and also from entering the data) was that some manufacturers fixed the FFD so it is independent of focal length, while others did not.

[ulf]

Nice graph!

 

It is clear that there are two groups.

 

I assume the the lenses with more or less fixed FFD are lenses intended for defined camera mounts.

They must be fixed to make it possible to use different lenses on a certain camera mount.

Most 24x36 SLR formats have a FFD between 40 and 50mm Canon, FD 42mm EOS 44 mm, Nikon F-mount 46,5mm

Her are some examples of some FFD:

https://en.wikipedia.org/wiki/Flange_focal_distance

 

The rest, increasing close to a ratio 1:1, following the focal lengths, are mainly without a direct connection to any specific camera model or camera mount type.

I think they are mainly projection-, enlarger- or copy-lenses or of a mount type that .

 

Andy, are there anyone of the lenses in the graph that do not match those descriptions?

[Andrea B.]

Is long focus distances a really good idea for these type of lenses?

Often they are optically optimised for the rather short distances normally found in enlargers.

Some of them might be acceptable for long focus distances, but not all.

 

I haven't been able to make any generalizations about using enlargers on the camera. Some are good at infinity, some are not. The UV-Rodagon is particularly good at infinity. One of my other Rodie enlargers (don't recall exactly which one just now) is not so good at infinity being a bit less sharp especially in corners.

[Andy Perrin]

Ulf, that sounds about right.

—

My EL-Nikkor 80mm works very well at infinity.