Lens Dismantling

[Andrew Bartram]

Does anyone have any experience in dismantling camera and enlarger lenses. I've a couple of specific problems
1) El-Nikkor 80mm enlarger lens with small amount of fungus on aninternal element
2) A cloudy element on a Yashicamat 124g

The enlarger lens has three screws on the back which look like a starting point but both have diametrically opposite "slots" on the lens faces presumably to insert some kind of specialst "unwinding device"

Look forward to hearing from the wise and experienced.....

Andrew B

[Sandeha Lynch]

I always reckon repairability is an important factor before a lens can be described as a good design. Some have mechanical parts that will only fit one way (great !!) others have a level of complexity (and the requirement of special tools) that verges on criminal.

Your three screws on the rear face are the starting point. Find a screwdriver that fits properly and don't **** up the heads of them. That may already be a difficult enough challenge. Once the rear plate is off, you may be able to unscrew the rear lens group by hand, or you will need some sort of grip that will fit the opposing slots. There are specialist spanner wrenches (http://www.micro-tools.de/mm5/e_spanner.htm) for this, but you might well find that a simple steel ruler will do the job perfectly well.

To remove the rear element on the 124, you may have to fashion a long tool that fits the slots without touching the glass. I ground down the ends of a steel rule to fit for one of my TLRs.

Lens groups usually twist apart, but a proper grip is vital to avoid crushing any threads, let alone crunching any glass. Some don't of course, if the elements have been glued in place.

Several days in sunlight should kill the fungus spores, though this won't remove the evidence. Methylated spirits will also kill them and clean them, though it may also remove any lens coating if its weak. Try an ordinary window or spectacle cleaner first.

Don't injure yourself. :)

[Andrew Bartram]

Sandeha

I'll try the enlarger lens first.
I was given it so less to lose.

Thanks for the tips

Andrew

[alfie]

You can see a tool for undoing those rings here http://www.film-and-darkroom-user.org.uk/forum/showthread.php?t=1127 it is also a cautionary tale. The main things are, take it easy, dont force anything, take notes (or digipics) an oblique light source is good for making sure these is no dust when assembling.

[Andrew Bartram]

managed to remove rear lens elements from the El Nikkor and fungus sucessfully removed.

[Sandeha Lynch]

Yeah, but did you manage to put it back after? :D :cool: :D

[Rob Archer]

I've been following this with interst as I've got an EL-Nikkor 50mm with fungus. I'd kind of given it up as lost until now! Andrew - how easy was it to get back together?

Rob

[Steve Smith]

Dismantling is easy. It's mantling it back together again which often causes problems.


Steve.

[Miha]

OT:

Just wondering, are EL-Nikkors prone to fungus infection? My 50mm was recently cleaned, but my 80mm is still OK. They were purchased new 12 / 10 years ago.

Miha

[Andrew Bartram]

I've been following this with interst as I've got an EL-Nikkor 50mm with fungus. I'd kind of given it up as lost until now! Andrew - how easy was it to get back together?

Rob

Hi Rob

Can't make the next meet up but hope to see you again soon.

With regard the El Nikkor 80mm I simply removed the rear elements which exposed the fungus. I used a cotton bud soaked in a bit of alcohol which removed the fungus completely.
A sharp flat bladed kitchen knife acted as a removal tool, putting the blade across the two grooves on the rear element which came away as a complete unit. After "repair" it simply screwd back again. No problems.

Happy to compare notes in person if you like. Am in KL this Saturday afternoon at in-laws in South Wootton for a family gathering. You are welcome to pop over as they will have a barrel of Timothy Taylors!!!

regards

Andrew

[Rob Archer]

sAdly, I can't make Saturday, Andrew - it's my son's 2nd birthday party, although I must admit the Timothy Taylors sounds enticing!

I'm going to have a go at my lens tomorrow evening. I'll let you know the outcome.

All the best

Rob

[Rob Archer]

I've just dismantled, cleaned and reassembled my EL-Nikkor 50mm. It took about an hour and I was surprised how straightforward it was. I'm going to leave the lens out in the consetvatory tomorrow for the sun to do it's work.

I'm in the darkroom for a bit wednesday, so I'll know if I've put it together OK!

Thanks for raising this Andrew, I wouldn't have bothered trying otherwise and would probably have ended up chucking the lens out!

Thanks

Rob

[Sandeha Lynch]

Stick a piece of silver foil underneath the lens, Rob, so that the sunlight gets reflected back through it.

[Andrew Bartram]

I've just dismantled, cleaned and reassembled my EL-Nikkor 50mm. It took about an hour and I was surprised how straightforward it was. I'm going to leave the lens out in the consetvatory tomorrow for the sun to do it's work.

I'm in the darkroom for a bit wednesday, so I'll know if I've put it together OK!

Thanks for raising this Andrew, I wouldn't have bothered trying otherwise and would probably have ended up chucking the lens out!

Thanks

Rob

no probs

[Rob Archer]

Stick a piece of silver foil underneath the lens, Rob, so that the sunlight gets reflected back through it.

Great idea , Sandeha - how long should I leave it in the sun for?

Rob

[Sandeha Lynch]

I can't say for sure, Rob. It's the UV that does the trick, and that's variable. I've usually left mine for three days of clear weather, turning them from time to time. Hope that helps.

[Andrew Bartram]

Update

Using a filed down end of a steel rule, unscrewed rear lens assembly from the Yashicamat, cleaned all surfaces and replaced. Looks good so far and saved a few bob.

Thanks for all the help

[Dave]

OT:

Just wondering, are EL-Nikkors prone to fungus infection? My 50mm was recently cleaned, but my 80mm is still OK. They were purchased new 12 / 10 years ago.

Miha

I don't think any lens is more prone to fungus than any other. It's more a question of use and storage. If a lens gets wet, then it needs careful drying immediately. Similarly if it's used or stored in humid conditions, then fungus growth will be encouraged.

[Mike O'Pray]

I also have an El Nikkor 50mm enlarger lens as do many others or enough do to make an article on dismantling with pics worthwhile if you can devote the time.

So far mine seems OK but there might come a day.....

Thanks

Mike

[Rob Archer]

I've just tried printing with my cleaned and re-assembled lens and coulnt work out why I could only get the very centre of the image sharp. Took the les apart again and realised I'd put the rear element in back-to-front!

Sorted it and works as good as ever now!

The motto of the story is to make a not of how anything goes if there's any doubt!

Rob

[Andrew Bartram]

I don't think any lens is more prone to fungus than any other. It's more a question of use and storage. If a lens gets wet, then it needs careful drying immediately. Similarly if it's used or stored in humid conditions, then fungus growth will be encouraged.

My 80mm El Nikkor came as a job lot inc Kaiser V enlarger, 20X16 Beard, timers, fibre and RC print dryers and loads of other stuff that I bought off e-bay a year or so ago. When I picked it all up it some of the stuff had clearly been stored in damp conditions so I guess that's the cause of the fungus.

Out of interest how do people store their lenses? - I have my 50mm and 80mm Nikkors on the Meopta and Kaiser all the time, others sit around the enlarger in plastic cases. Some dessiccant gel may be in some but not all and what is there is probably past its sell by date.

Not sure what the humidity is in my darkroom but I guess when the Nova slot printer is on, water in a tray and the Nova print washer going the humitiy could well be quite high.

I notice on e-bay that you can buy small rechargable dehumidifiers for small spaces, any use you think?

Andrew

[Richard Gould]

I keep either my durst or meopta lens on the enlarger all the time, the others in the plastic 'lens keepers", I always keep a lens cap on the lens on the enlarger, and I keep a plastic bag over the enlarger, Richard

[Bob]

I've just tried printing with my cleaned and re-assembled lens and coulnt work out why I could only get the very centre of the image sharp. Took the les apart again and realised I'd put the rear element in back-to-front!

Sorted it and works as good as ever now!

The motto of the story is to make a not of how anything goes if there's any doubt!

Rob
One of the few good uses for a digital camera ;)!

[Niall Bell]

I've read all this with interest. One question pops up for me: how can you reassemble a lens in an atmosphere that will be far from dust free (even the cleanest houses are full of dust) and not have a lens with specs all through?

I've never had the guts to try what you guys have done and always sent lenses away for repair.

So, how have the lenses performed?

Niall

[B&W Neil]

All my enlarger lenses are kept in their perspex / plastic homes when not in use. I also store them on a high shelf and keep a oil filled heater on low tick-over during the cold damp months. Being in the damp west, and having a darkroom in shed, I have been concerned about fungus but so far - no problems. The shed has also been very well insulated which I think helps.

Neil.

[Andrew Bartram]

I've read all this with interest. One question pops up for me: how can you reassemble a lens in an atmosphere that will be far from dust free (even the cleanest houses are full of dust) and not have a lens with specs all through?

I've never had the guts to try what you guys have done and always sent lenses away for repair.

So, how have the lenses performed?

Niall

Used the 80mm Nikkor over the weekend.
All fine
My guess is that the odd spec of dust trapped inside following such a DIY job isn't an issue.
Clean air blower, care and dismantling in our carpet free garden room als helped.

Andrew