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UltravioletPhotography

Current setup to mount EL-Nikkor 135mm f/5.6 to Full Spectrum 5Dmk2


SteveCampbell

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SteveCampbell

I've been trying to put together a setup that allows me to create high-resolution, ultraviolet-compatible portraits with reasonable subject isolation. This is what I've come up with thus far. It just barely focuses to infinity, and is able to focus down to approximately 0.75m.

 

Full spectrum 5Dmk2 with QV-1 LCD viewfinder + 7mm + 14mm extension tubes + EF->M42 + 35-90mm M42 helicoid + M42->M39 + El-Nikkor 135/5.6 film enlarger lens + 43mm->52mm step-up + 52mm UG-11 + 52mm BG-40 + silly lens hood

 

What success have others had in UV portrait lenses?

post-156-0-33653100-1503534866.jpg

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That is truly a fine looking rig when all put together !!!

 

With the tubes and the helicoid, will you need something under that to avoid any wobble? ;) :lol:

How do you like that QV-1? I could definitely use a new thingie over my LCD.

 

I'm sitting here trying to sort out what are your actual focal length possibilities to over the Canon sensor. I give up! Tubes, helicoid all contributing something, eh?

 

Portrait focal lengths tends to be a personal value and me, I've always had the best portrait results with a 135mm focal length (with respect to "full frame", that is). I can stay at 105mm and do OK. But have never done well at 180mm, just too long for me to see faces properly.

 

I haven't made hardly any UV portraits even though I've carefully collected five 135/3.5 UV-capable lenses to enjoy. :) My 135s are branded Kyoei Optical, Lentar, Asahi Takumar (old Pentax), Hanimar and a Kuribayashi Petri Orrikor. They are all clean, nice old lenses with lots of metal and a nice heft. The Kuri is really heavy. These 5 lenses are not all equally UV capable but I don't recall at the moment which is good, which is not. I tend to like the Takumar the best for the way it "draws", as they say.

 

I'm thinking that the main thing you will need to fight against is the chromatic aberrations which might occur in a non-dedicated UV-capable lens? Do post us a couple of examples as you experiment with this nice set up!

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Looks nice! For me, that hardest problem I have with portraits is finding a willing model. The word has gotten out that UV photos show skin "damage" and now all potential subjects flee the scene. They feel ignorance is bliss, apparently.
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SteveCampbell

Thanks for the reply Andrea!

 

It's all quite stable, surprisingly! The QV-1 is my 4th LCD viewfinder, and by far the best. It makes a massive difference if you're relying on an LCD, and manual focusing is so much easier (especially with magic lantern).

 

I suppose my three largest considerations for portrait lenses are depth of field (as shallow as possible), perspective (35mm widest usable only if very large aperture, 135 longest usable due to long working distance), and telephoto compression (135 strong here). While in IR and visible I prefer the 85/1.2 due to the balance of all these factors, In UV I'm expecting to use longer focal lengths like the 135 for subject isolation via telephoto compression, as it's so hard to find large-aperture lenses that can accommodate UV.

 

That being said, the 135mm spot tests you posted about a while back intrigued me. The f/3.5 would certainly help, but I wasn't sure about wide-open sharpness or transmission characteristics.

 

My goal when planning the setup was to (1) barely achieve infinity focus at extenion tube + retracted helicoid length and (2) have as large a helicoid travel distance as possible to accommodate near focusing. With the 80/5.6 I got away with using only a helicod, but with the huge 123mm focus flange distance on the 135/5.6 I needed to add extension tubes to the setup.

 

Fortunately the old EL-Nikkor range was optimised for chromatic abberation down to 350nm, and some brief tests in strong backlightly didn't yield any noteworthy CA. I was also impressed with the resolution it was capable of. I'll be sure to post examples once I have time to take some proper photos!

 

That is truly a fine looking rig when all put together !!!

 

With the tubes and the helicoid, will you need something under that to avoid any wobble? ;) :lol:

How do you like that QV-1? I could definitely use a new thingie over my LCD.

 

I'm sitting here trying to sort out what are your actual focal length possibilities to over the Canon sensor. I give up! Tubes, helicoid all contributing something, eh?

 

Portrait focal lengths tends to be a personal value and me, I've always had the best portrait results with a 135mm focal length (with respect to "full frame", that is). I can stay at 105mm and do OK. But have never done well at 180mm, just too long for me to see faces properly.

 

I haven't made hardly any UV portraits even though I've carefully collected five 135/3.5 UV-capable lenses to enjoy. :) My 135s are branded Kyoei Optical, Lentar, Asahi Takumar (old Pentax), Hanimar and a Kuribayashi Petri Orrikor. They are all clean, nice old lenses with lots of metal and a nice heft. The Kuri is really heavy. These 5 lenses are not all equally UV capable but I don't recall at the moment which is good, which is not. I tend to like the Takumar the best for the way it "draws", as they say.

 

I'm thinking that the main thing you will need to fight against is the chromatic aberrations which might occur in a non-dedicated UV-capable lens? Do post us a couple of examples as you experiment with this nice set up!

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SteveCampbell

Ah yes, I prefer to emphasize the "intensity" and "ruggedness" of the results! Also, bringing out freckles can be quite flattering, as is the slimming effect UV tends to provide. I'll also mix up my shoots with IR, full-spectrum, and visible, as I've noticed that every model seems to have a different part of the spectrum that flatters them best. Also, I've always given my models 100% veto power on any photo I'm planning on uploading!

 

Looks nice! For me, that hardest problem I have with portraits is finding a willing model. The word has gotten out that UV photos show skin "damage" and now all potential subjects flee the scene. They feel ignorance is bliss, apparently.

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Wait, what??? Slimming effect? There is a UV slimming effect? This becoming-much-too-stout advanced-middle-aged lady is now looking to quickly get herself in front of a UV lens!!! :D :lol: :rolleyes:

 

**********

 

....every model seems to have a different part of the spectrum that flatters them best.

 

Interesting observation. But makes sense given that we are all differently skinned with different colors of hair and eyes and so forth.

 

*******

 

That being said, the 135mm spot tests you posted about a while back intrigued me. The f/3.5 would certainly help, but I wasn't sure about wide-open sharpness or transmission characteristics.

 

No surprise that purchasing an old lens is a dice roll. I don't think we can make general observations about these various brands of manual 135/3.5s with respect to their sharpness or micro-contrasts or other lens qualities. One just keeps looking for a good one.

 

Very generally speaking, I've yet to find any lens at its sharpest wide-open. Might have to stop down at.least.one., yes?

 

*******

 

You mentioned 85mm which I know is considered a classic portrait length. I am completely awkward with an 85mm focal length (over 35mm frame). I can't seem to make my feet move in the correct direction. Give me 105 or 135 and I'm happy as a little UV-bug.

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Ah yes, I prefer to emphasize the "intensity" and "ruggedness" of the results! Also, bringing out freckles can be quite flattering, as is the slimming effect UV tends to provide. I'll also mix up my shoots with IR, full-spectrum, and visible, as I've noticed that every model seems to have a different part of the spectrum that flatters them best. Also, I've always given my models 100% veto power on any photo I'm planning on uploading!

Yeah, I made the mistake of showing one woman the photo IN the camera -- with the usual UV white balance! The poor lady was rather distressed to discover she was purple.

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enricosavazzi

These focusing helicoids are reasonably priced and precise. However, one problem I found with the longer helicoids used with this and similar lenses is that the displacement is linear, i.e., a rotation of a given angle produces the same change in helicoid length, along the whole range of extension.

 

Focusing near infinity usually requires very small changes in extension. In the close-up and macro range, a larger change of extension is usually required (and focusing is best done by moving the lens + camera as a whole after setting the magnification with the helicoid).

 

If you are satisfied with the focusing precision near infinity with your current setup, no problem. Just keep using your present setup. If you want a better focusing precision (i.e., a wider rotation angle to achieve the same change of extension) in a subset of the focusing range, then the simplest solution is to use a much shorter helicoid, together with a stack of extension tubes to reach the desired length.

 

All helicoids of this type available on eBay that I have seen (I own about a dozen of different lengths and types) are linear, and all rotate by roughly the same angle (less than one full turn) from minimum to maximum length. None that I am aware of has a nonlinear extension travel. Most well-designed lenses instead have non-linear focusing slots, to make focusing comfortable both near infinity and in the close range.

 

In practice, with my suggestion you end up with two separate sets of helicoid + extension tubes, one optimized for focusing on distant subjects but not capable of focusing to close range, the other focusing from infinity to close-up but difficult to use for focusing near infinity.

 

PS - it is even possible to stack two helicoids of very different lengths, to get the "best of both worlds", but then you need to remember which one is best for which focusing range. And not many photographers can boast of having a lens with two focusing rings! But dual coarse and fine focusing knobs are available on most microscopes, so nothing really new.

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SteveCampbell

Very good point with the infinity focus! I hadn't noticed the nonlinearity up to now. Fortunately liveview focusing with the EVF makes things pretty easy. However I can always stack my 17-31mm and 35-90mm helicoids should the need arise

 

These focusing helicoids are reasonably priced and precise. However, one problem I found with the longer helicoids used with this and similar lenses is that the displacement is linear, i.e., a rotation of a given angle produces the same change in helicoid length, along the whole range of extension.

 

Focusing near infinity usually requires very small changes in extension. In the close-up and macro range, a larger change of extension is usually required (and focusing is best done by moving the lens + camera as a whole after setting the magnification with the helicoid).

 

If you are satisfied with the focusing precision near infinity with your current setup, no problem. Just keep using your present setup. If you want a better focusing precision (i.e., a wider rotation angle to achieve the same change of extension) in a subset of the focusing range, then the simplest solution is to use a much shorter helicoid, together with a stack of extension tubes to reach the desired length.

 

All helicoids of this type available on eBay that I have seen (I own about a dozen of different lengths and types) are linear, and all rotate by roughly the same angle (less than one full turn) from minimum to maximum length. None that I am aware of has a nonlinear extension travel. Most well-designed lenses instead have non-linear focusing slots, to make focusing comfortable both near infinity and in the close range.

 

In practice, with my suggestion you end up with two separate sets of helicoid + extension tubes, one optimized for focusing on distant subjects but not capable of focusing to close range, the other focusing from infinity to close-up but difficult to use for focusing near infinity.

 

PS - it is even possible to stack two helicoids of very different lengths, to get the "best of both worlds", but then you need to remember which one is best for which focusing range. And not many photographers can boast of having a lens with two focusing rings! But dual coarse and fine focusing knobs are available on most microscopes, so nothing really new.

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SteveCampbell
I took the rig out for a quick test run, and noticed some light leaking from the 35-90mm helicoid ... has anyone else experienced this?
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enricosavazzi

I have not had this problem. Do you know if it is light entering through the helicoid barrel (somewhere along the sides where the sleeves move past each other)? This would qualify as a leak.

 

Another possibility is that it is not, strictly speaking, a leak but flare. The 135 mm covers a wide image circle, and therefore can illuminate a broad portion of the inner surface of the helicoid (especially when focused close), in addition to the camera sensor. From there, light can be reflected and diffused multiple times. Some helicoids have internal baffles, but not very effective. In this case, it may be necessary to add flocking and/or baffles. It is also necessary to use a deep lens shade not any wider than necessary to avoid darkening in the corners.

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SteveCampbell

It seems I have accused the wrong suspect! It was the extension tube all along. Removing it from the setup actually makes a fair bit of sense since the helicoid along covers pretty much all of the working distance I would need to take portraits; I don't think I'll need anywhere near as close a focus on this thing. Besides, the whole setup was looking a little comically unwieldy - makes for great equipment posts, less so practical usage.

 

I have not had this problem. Do you know if it is light entering through the helicoid barrel (somewhere along the sides where the sleeves move past each other)? This would qualify as a leak.

 

Another possibility is that it is not, strictly speaking, a leak but flare. The 135 mm covers a wide image circle, and therefore can illuminate a broad portion of the inner surface of the helicoid (especially when focused close), in addition to the camera sensor. From there, light can be reflected and diffused multiple times. Some helicoids have internal baffles, but not very effective. In this case, it may be necessary to add flocking and/or baffles. It is also necessary to use a deep lens shade not any wider than necessary to avoid darkening in the corners.

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My experience with helicoids is different than Enricos.

Mine have a very big span of rotation angles.

 

- Range ----- Type ------ Full turn ----- Make

12-19mm - M42-M42 -- 1/3 turn ----- Fotsay

17-32mm - M42-M42 -- 1/2 turn ----- ?

24-55mm - M42-M42 --- 1 turn ------- ?

25-55mm - M52-M42 -- 1+3/4 turn --- Pixco

35-90mm - M52-M42 -- 1+3/4 turn --- ?

 

post-150-0-39468100-1503756432.jpgpost-150-0-93398700-1503756483.jpg

 

For best focus resolution the short M52 helicoid would be best, but the longer one is quite good too.

To mount a M42 lens or tube to the M52mm side some type of M42 adapter is needed.

A M52 to M42 step down ring can be used if the minimum length of the helicoid is acceptable.

 

I use a modified 35-90mm M52-M42 helicoid for my El-Nikkor 80mm and 105mm lenses.

I'll post something about that modification soon.

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