Lens comparisons: El Nikkor 80mm, OD. Industries and X135

[msubees]

Igor, thanks for posting an instruction. mine seems to be stuck quite tight.

 

Sorry, kds says it is "a Barlow lens btw. to lengthen the back focal length". but it is not a magnifying class..but it shrinks when I looked through.

[igoriginal]

On top of sample variation a lot of these older vintage lenses also depend on how they were treated by their previous owners, the climate they were in (dry gives less fungus than humid), how many times they dropped them etc

 

That's all true, to an extent ... because internal haze ("fogging", in particular) is the real image killer. Fungus, not necessarily (unless it is quite thick and has taken over the entire internal environment). And cleaning marks, scratches, and even actual cracks in the glass will have very little (if any) effects on actual imaging.

 

There was once a well-regarded article done on various forms of lens damage, and how these damages affected image quality. And the shocking results showed that actual glass scratching, nicking, and even cracking had the least effects on imaging! Someone in the study deliberately took a hammer to the front element of a lens, and created cracks in the glass across the entire diameter. To everyone's surprise, the image quality was still not heavily compromised!

 

See this: http://www.lensrenta...ement-scratches

 

Thus, I am less concerned about how many times the lens was dropped on the ground, and even do not care much if it even has cleaning marks and scratches on the glass. (In fact, I own a Kyoei Super-Acall 135mm lens, which is known to be a good UV performer, with an actual part of the front element having been cracked, and still no discernible loss in image quality) ... and more concerned with internal fogging / haze, which is the real image killer.

 

I understand that many of us photographers were raised to believe in the conventional wisdom to "guard against scratching the glass, at all costs", and now we find out that scratches (and even moderate / mild cracking) in the glass are the least of our worries. Haze / lens separation / fogging are the ones to look out for.

 

It's not that I am saying that scratches / nicks / cracks don't matter at all. Sure they matter, to an extent. But ... the scratching / nicking / cracking of the glass must be quite extreme to be worth worrying about.

 

(And, I made out like a bandit, winning the Ebay auction on that Kyoei 135mm with the small crack on the front element - all for $50 USD! - because everyone else on Ebay seemed to shy away from putting a bid on it. Knowledge is power, as they say. :D )

[JCDowdy]

I have an El Nikkor 80mm lens, plastic not chrome :D

It needs a good clean inside (fungus?).

Is there a tutorial for opening up these El Nikkor lenses & re-assembly, or is it just simple with no adjustments or traps ?

Col

 

Colin,

Here is a step by step with photos on a 75mm N model, probably close enough.

http://photomiser.com/repair-el-nikkor-lens/

Good Luck!

[JCDowdy]

Sorry, kds says it is "a Barlow lens btw. to lengthen the back focal length". but it is not a magnifying class..but it shrinks when I looked through.

Of course! I don't know why I said focal reducer! ..what was I thinking...

However, I would still omit the UV grade M42 to Nikon F focal reducer teleconverter (aka barlow lens) and go with a simple M42 to µ4/3 which has no optics.

[colinbm]

Thanks for the link John, that looks pretty much like the El Nikkor 80mm lens is, inside.

The white plastic internally, is what stops the external light from the aperture index numbers from entering the lens light path. I will see if I can black this part ? I know I can turn the opening for the light entry on the bottom flange too.

Cheers

Col

[JCDowdy]

The white plastic internally, is what stops the external light from the aperture index numbers from entering the lens light path. I will see if I can black this part ? I know I can turn the opening for the light entry on the bottom flange too.

 

If it is not to much trouble, please first try simply rotating the opening and advise us if that alone will suffice.

I have just acquired an "N" model which is yet to be set up.

[colinbm]

I have looked at the light hole in the bottom of the El Nikkor 80mm lens.

After turning the retaining ring 120degs, I can't see any light leaks from here. There is still a soft glow through the aperture number window into the white plastic interior. I have painted, with satin black nail varnish, the raised portion of the white interior, behind the aperture dial numbers. No noticeable light leaks now.

The front optical element appears to be a triplet & to get it apart seems to need the ring with the Nikon writing on it, inside the filter thread ring, removed before the retaining ring with the two slots will unscrew completely.

How the front, labelled ring is unscrewed I don't know ??

Col

[JCDowdy]

After turning the retaining ring 120degs, I can't see any light leaks from here. There is still a soft glow through the aperture number window into the white plastic interior. I have painted, with satin black nail varnish, the raised portion of the white interior, behind the aperture dial numbers. No noticeable light leaks now.

Thanks Col,

Your experience is consistent with that documented on Photomiser in that rotating of the window 120° doesn't seem to completely block the light leak. However may I ask, did you try any shots with the window rotated before painting the light conducting interior part? I must confess I am loathe to invade the interior of an otherwise pristine 63mm. I shall take the less permanent approach and simply cover the outside with a nice wide black rubber band.

Great info!

[colinbm]

Thanks John

I haven't assembled the lens yet as I am still trying to work out how to get the front elements out to clean ?

There doesn't seem to be a back entrance to the front element only from the front, by first removing the Nikkor ring with the writing first, then the front element ring ?

I have tested the light path visually with a narrow beam torch & seeing what light came inside.

Cheers

Col

[colinbm]

I have bit the bullet & did the only thing I could think to do & that was to drill two tiny 1mm holes, opposite each other, into the Nikkor ring with the writing on it, at the front of the lens. I used a pair of engineer dividers to straddle the holes & was able to unscrew the front ring from within the filter thread hole. Yes it was a bit tight & too tight for the rubber tool.

Now I have access to all the lenses { EL-Nikkor 80mmF5.6N - M39 Screw Mount. (Lens Construction 6 elements in 4 groups / Orthometar Type Lens) } & they will be getting a good disinfection & clean :D

Col

[igoriginal]

I have bit the bullet & did the only thing I could think to do & that was to drill two tiny 1mm holes, opposite each other, into the Nikkor ring with the writing on it, at the front of the lens. I used a pair of engineer dividers to straddle the holes & was able to unscrew the front ring from within the filter thread hole. Yes it was a bit tight & too tight for the rubber tool.

Now I have access to all the lenses { EL-Nikkor 80mmF5.6N - M39 Screw Mount. (Lens Construction 6 elements in 4 groups / Orthometar Type Lens) } & they will be getting a good disinfection & clean :D

Col

 

Way to go, Col! Awesome.

[colinbm]

That fungus, even though it is light, it is stubborn stuff to remove ?

Col

[igoriginal]

That fungus, even though it is light, it is stubborn stuff to remove ?

Col

 

What I have read, is that a full immersion in white vinegar (for an hour or two) works on some of the more stubborn fungus. Meaning, an acid bath, when an ammonia-based dousing (from many other "cleaners") doesn't do the trick. Provided that it hasn't started to actually etch into the glass, itself, which is incurable in any sense (you can't "add back" glass that is missing.) Although, actual glass which has been lightly etched may not necessarily impact image quality to a significant degree.

 

And although an acid bath (even in a weak acid solution such as vinegar, which is something like 3% to 4% acid, by concentration) is contraindicated for "modern" lenses that are treated with specialized coatings ... we UV photographers do not have to worry about coatings being stripped from the element, since this can only improve UV transmission, and not take away from it. :D

 

In any case, do some research of your own, just to confirm. Don't just take my word for it. However, I have successfully soaked (and treated) two prior fungus infestations (however light), by soaking individual elements in white vinegar. In fact, I even forgot about them being left to soak, once, and left the elements soaking in the white vinegar overnight. All without any negative impact.

 

Again, though. Do some research and reading on your own, just to confirm. I'm no expert on these matters.

[colinbm]

Thanks Iggy, they are in for the swim :D

Col

[colinbm]

The glass is now a lot cleaner, thanks Iggy for the vinegar immersion trick :D

But I hope I have learnt something........don't buy crap lenses ??

Col

[JCDowdy]

...... I hope I have learnt something........don't buy crap lenses ??l

 

I don't know, there is something to be valued in the experience itself.

There is intrinsic value if you have indeed rescued the lens and find it useful.

There is technical knowledge gained, shared, and clearly appreciated by others.

If nothing else at least some entertainment value! :D

[JCDowdy]

Igor, thanks for posting an instruction. mine seems to be stuck quite tight.

 

Sorry, kds says it is "a Barlow lens btw. to lengthen the back focal length". but it is not a magnifying class..but it shrinks when I looked through.

 

Zach,

 

Your original thread seems to have drifted off topic, apologies for my part in that.

 

Have you sorted out the lens mounting of your X135 to your µ4/3 G5?

 

Your X135 vendor, KDS, has a brief tutorial entitled "How to determine the length of a focusing helicoid" on his blog which might help in determining your set up.

 

John

[Andrea B.]

Guys, whatever you use to clean fungus off your lens elements, please be careful. And be very careful indeed if the lens elements have any kinds of coatings. It's hard to know whether coatings (metal oxides??) would/wouldn't be damaged by either acidic vinegar or basic ammonia, however dilute the solutions might be.

 

Lens fungus eventually etches the glass by secretion of acid & enzymes. Vinegar, while a very weak acid, could potentially add to the etching in the case where etching has already begun?? So don't leave lens elements soaking forever in vinegar - or anything else. There is an old Leica or Leitz (can't remember which one) recipe which uses a very dilute mix of plain ammonia and hydrogen peroxide in distilled water should you wish to eschew Windex. (The blue dye seems problematic to me.)

 

My connection or laptop or something seems slow/jumpy tonight. So I'm having trouble scrolling around to see if we mentioned somewhere above that setting lenses outdoors for a little UV bath in the sunshine can be useful for killing fungus spores which might be scattered throughout a lens and not just on the surface of the glass. If we have mentioned this already, then we have now mentioned it twice. :D :D :D

 

Carry on !!

[igoriginal]

Guys, whatever you use to clean fungus off your lens elements, please be careful. And be very careful indeed if the lens elements have any kinds of coatings. It's hard to know whether coatings (metal oxides??) would/wouldn't be damaged by either acidic vinegar or basic ammonia, however dilute the solutions might be.

 

I would be wary to use an acid bath, even a weaker one such as white vinegar, if it involved cleaning the elements of the more expensive and "modern", auto-focusing, electronic lenses with complex, proprietary coatings.

 

But, as far as the more vintage lenses which turn out to be of some UV-transmissive value (enlarging lenses / projections lenses / old, manual-focusing prime lenses), I don't see how a weak acid bath would be detrimental in any way. If anything, most of the coatings of the more vintage lenses are poor to begin with, if there are any coatings at all. And stripping away coatings, in many cases, has been shown to actually improve UV transmission, has it not?

 

So, it depends on what we plan to soak. Definitely not the elements of our expensive, auto-focusing, proprietary-coating lenses. But as for the vintage, manually-focusing primes ... I don't see any issues with a weak acid bath. I actually see only advantages. I have cleaned over 200 vintage lenses with white vinegar, all without incident.

 

However, ammonia-based cleaners are indeed limited in their cleaning potential, whereas acid bathing is quite effective, when all else fails. This is why acid bathing is a common step, within many industries of production (Textiles, inorganic chemistry, etc.)

 

Lens fungus eventually etches the glass by secretion of acid & enzymes. Vinegar, while a very weak acid, could potentially add to the etching in the case where etching has already begun??

 

The acids and enzymes secreted by fungal growth, which eventually may or may not etch into glass, is a very slow process of catalyzation. It takes years, in many cases. Not weeks, and not even months.

 

The acid concentration within white vinegar (roughly between 3% to 5%, standard cooking grade, but can run higher in some cases, as high as 10%), because it is weak as far as acid solutions go (mostly acetic acid), would have no chance in contributing to further etching into lens-grade glass (or most other types of glass, for that matter). It would take many years more, to become a contributing factor (if at all). It certainly wouldn't happen during an overnight soak. Wouldn't even happen in a week-long soak. Silicon dioxide is that tough.

 

(I know because part of my coarse work within my line of work - biochemistry / physiology - involved extensive lab tests within the fields of metabolism and enzyme reactions concerning various organisms).

 

For evidence, just look at a glass jar of pickles, okra, relish, or tobasco peppers packed in acetic acid (or vinegar), for example. Absolutely no sign of "eating away at the glass", even when these fermented food products are kept in storage for years.

 

Even gastric acids secreted by the cells of our stomach lining, of which hydrochloric acid is a primary component, wouldn't stand a chance of eating away at silicon dioxide so quickly, if we happened to swallow some fragments of it (such as sand or glass shards). And hydrochloric acid (secreted by our stomach) is more corrosive than acetic acid (within vinegar), by many orders.

 

Now, as far as more softer, specialized lenses involving fluorite composite glass (for deeper UV transmission) ... THIS may be an entirely different matter. There may be some additional reactive chemistry, from acid exposure. Although this is not something I am particularly knowledgeable in. I only specialize in biological systems, as far as reactions go. But, it would be interesting to find out, wouldn't it? (Without actually trying it on a fluorite element, of course. Haha.)

 

I do know that hydroFLUORIC acid does react strongly and quickly with silicon dioxide, as opposed to some other acids. Which is why hydrofluoric acid is used as a solvent for silicon, in industrial processes.

[igoriginal]

Guys, whatever you use to clean fungus off your lens elements, please be careful. And be very careful indeed if the lens elements have any kinds of coatings. It's hard to know whether coatings (metal oxides??) would/wouldn't be damaged by either acidic vinegar or basic ammonia, however dilute the solutions might be.

 

I would definitely be wary to use an acid bath, even a weaker one such as white vinegar, if it involved cleaning the elements of the more expensive and "modern", auto-focusing / electronic lenses with complex, proprietary coatings.

 

But, as far as the more vintage lenses which turn out to be of some UV-transmissive value (enlarging lenses / projections lenses / old, manual-focusing prime lenses), I don't see how a weak (and short-term) acid bath would be detrimental in any way. If anything, many of the rudimentary coatings of the more vintage lenses are poor and quite inadequate to begin with, if there are any coatings at all. And stripping away the coatings of older lenses, in many cases, has been shown to actually improve UV transmission, has it not?

 

(Not to mention, that lens coatings is what fungus tends to thrive on, and metabolize / eat, to begin with. Hence, strip away any residual and weak coatings, and you essentially eliminate the "fungus food" - coatings. Which is why fungus infestation is so rare, when it comes to completely bare / uncoated glass).

 

So, it depends on what we plan to soak. Definitely not the elements of our expensive, auto-focusing, proprietary-coating lenses. But as for the vintage, manually-focusing primes ... I don't see any issues with a weak acid bath. I actually see only advantages. I have cleaned over 200 vintage lenses with white vinegar, and have fully emersed / soaked 2 of them, all without incident.

 

And, ammonia-based cleaners are indeed limited in their cleaning potential, whereas acid bathing is quite effective, when all else fails. This is why acid bathing is a common step of cleaning / sanitation, within many industries of production (Textiles, electronics / semi-conductors, inorganic chemistry, surgical tool cleaning / bleaching, etc.)

 

Lens fungus eventually etches the glass by secretion of acid & enzymes. Vinegar, while a very weak acid, could potentially add to the etching in the case where etching has already begun??

 

The acids and enzymes secreted by fungal growth (and even bacterial growth), which eventually may or may not etch into glass, is a very slow process of catalyzation. It takes years, in many cases. Not weeks, and not even months in many cases. It's a tedious process for these organisms.

 

The acid concentration within white vinegar (roughly between 3% to 5%, standard cooking grade, but can run higher in some cases, as high as 10%), because it is weak as far as acid solutions go (mostly acetic acid), would have no chance in contributing to further etching into lens-grade glass (or most other types of glass, for that matter). It would take many years more, to possibly become a contributing factor (if at all). It certainly wouldn't happen during an overnight soak. Probably wouldn't even happen in a week-long soak. Silicon dioxide is that tough.

 

(I know because part of my coarse work within my line of collegiate studies - biochemistry / physiology - involved extensive lab tests within the fields of metabolism and enzyme reactions concerning various organisms).

 

For evidence, just look at a glass jar of pickles, okra, relish, or tobasco peppers packed in acetic acid (or vinegar), for example. Absolutely no sign of "eating away at the glass", even when these fermented food products are kept in storage for years.

 

Even gastric acids secreted by the cells of our stomach lining, of which hydrochloric acid is a primary component, wouldn't stand a chance of eating away at silicon dioxide so quickly, if we happened to swallow some fragments of it (such as sand or glass shards). And hydrochloric acid (secreted by our stomach) is more corrosive than acetic acid (within vinegar), by many orders.

 

Now, as far as other, specialized lenses constructed of quartz fluorite composite glass (for deeper UV transmission) ... this may be an entirely different matter. There may be some additional reactive chemistry possible, from acid exposure. Although this is not something I am particularly knowledgeable in. I only specialize primarily within the fields of biological systems, as far as chemical reactions go. But, it would be interesting to find out, wouldn't it? (Without actually trying it on one of our own fluorite elements, of course. Haha.)

 

I do know that hydrofluoric acid does react strongly and quickly with silicon dioxide (as well as other silicate / glass oxides) as opposed to some other acids. Which is why hydrofluoric acid is used as a solvent for silica / glass, in industrial processes.

[colinbm]

Thanks Iggy

I did get one or actually two surprises after the lenses had their vinegar bath, only for an hour though, it didn't affect the doublets bond.

It appears that the lenses, both doublets & the exposed surfaces, the one at the front & one at the rear, had a clear coating that concealed deep scratches on their surfaces.

Is this something that some unscrupulous operators would do, to make a sale ?

Anyway the glass is all clean, regardless of these scratches. I can't return the lens as I have done work on it. We live & learn (some slower then others :D

Col

[igoriginal]

It appears that the lenses, both doublets & the exposed surfaces, the one at the front & one at the rear, had a clear coating that concealed deep scratches on their surfaces.

Is this something that some unscrupulous operators would do, to make a sale?

 

Possibly. Who knows. If it was a cover up, it was probably some kind of clear acrylic or lacquer. Probably from a second-hand re-seller or pawn shop. Although, might not even put it past the possibility of an in-factory "quality control" measure by some bumbling worker or even a questionable manager more interested in "turn-over quotas", from back in the day (rather than discarding less than perfect specimens being spit out of the conveyor belt, which might have fallen off, or gotten accidentally "chewed up" by some dispensing / sorting machinery). Happens with coin mints, too (occasional misalignment, gouging, scratching, marring, mistamping, etc.) At least the minting of coins in the more distant past, anyway.

 

I really don't know how clear acrylic or lacquer would impact image quality, though. So, not sure who would attempt something like that, and why.

 

Who knows? The long line of how many trading hands this lens has lived through, before ending up in yours, could be quite an interesting history, in itself.

 

Anyway the glass is all clean, regardless of these scratches. I can't return the lens as I have done work on it. We live & learn (some slower then others :D

 

As JCDowdy pointed out, every experience is of some intrinsic value in terms of learning. And such lenses are certainly not the most expensive items to make experimental mistakes on. Right? Good thing. :D

[igoriginal]

I'd also be wary of how a weak acid bath could effect the "cementing" between elements.

 

Which is why I would probably only give an acid bath to mostly "air spaced" lens elements. Otherwise, maybe better to do a series of acid "wipes" (using a Dremel tool and a buffer / polisher attachment), rather than a full emersion, when dealing with glued or cemented pieces.

[colinbm]

Yes, the scratches 'could' be a manufacturing defect / cover-up, because I was surprised at the smoothness / polished look, of the scratches ??

And yes I didn't totally immerse the doublets, in case it affected the bond. I just used enough vinegar to cover the convex end of the doublet with the concave end upwards & the concave was filled with vinegar too.

Col

[igoriginal]

I just used enough vinegar to cover the convex end of the doublet with the concave end upwards & the concave was filled with vinegar too.

 

My thoughts, exactly! I was thinking through along some the very same lines of the various options, actually. :D Good call!