A FUNGUS Question.

[SiriusB]

Anyone suffered from this in an eyepiece? If so, what did you do?

.....& For those of you who don't know what i mean, apparently there's a fungus that will grow on lens coatings with the help of moist conditions.

Sounds bizzare i know, but true.

( So don't forget the silica gel in your storage box folks.)

Only ever seen it on camera lenses, where it can be pretty pretty bad,  & i think pretty much junks the lens.

Reason i ask is  i received EP in post i rather fancied would be a keeper, but has internal fungus,(not  that bad but noticeable)

Will send back  for refund unless  anyone thinks it's a practical & longterm proposition to clean  it off??

I could be looking a fair while longer for another example, but logically best to return.

I'd always assumed lens fungus could jump from lens to lens, so even if i could clean it  i'd be worried about an occular  fungal pandemic in the future.

Any thoughts?

Hope I've not given anyone nightmares or sparked an OCD cleaning & checking frenzy.😟

I doubt you'll  ever see a problem unless you pack away damp after observing or store in damp conditions.

My question is what if anything can/should be done should the problem arise?

Thanks.

 

 

[Alien 13]

Fungus can attack most optics that have lens coatings, camera lenses/binoculars especially the prism for some reason and of course scopes and eyepieces. You are correct that the spores can spread and contaminate other optics too.

The best fix is lots of sunlight or UV which will kill the spores but you can be left with glass that has been etched, cleaning with IPA or similar might remove some contamination if the fungus is caught early but its best to be vigilant..

Alan

[DaveL59]

as Alan said, UV will kill the spores. Coating may already be slightly etched, or more. To clean you'd need to be prepared to strip the optics down and clean the glass and other components, how complex that would be will depend on the eyepiece.

This may help in terms of cause, prevention and treating
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3864060/

 

[SiriusB]

Ok, cheers Alan & Dave, SGL on the ball as usual.

                                      Only 4 elements but sounds like best to return in this case & only try remedial work when you're already stuck with the EP?

  It's the potential spreading part i think is of most concern.

[SiriusB]

A Good link Dave.

.....& for all those who store their FMC Apo's in the shed...... sounds like that's a big no no.

....& for those with less sympathetic other halves, now's the chance to explain why it needs to have pride of place in the  dry  living room.😉

 

[Alien 13]

4 minutes ago, SiriusB said:

A Good link Dave.

.....& for all those who store their FMC Apo's in the shed...... sounds like that's a big no no.

....& for those with less sympathetic other halves, now's the chance to explain why it needs to have pride of place in the  dry  living room.😉

 

Storage is ok in a shed provided that the scope gets some fresh air and sunshine from time to time but all my stuff is in the house.....

As for the spreading you only have to look at how soda bread is made, spores are everywhere..

Alan

[DaveL59]

out of interest, what is the eyepiece you're looking at? Sounds like it was a gem and rare to find?

[Don Pensack]

I would simply dismantle it and clean it with lens cleaner.

Unless the eyepiece is more than 50 years old, it can probably be successfully cleaned and reassembled.

I've done so with some eyepieces from the 1890s that needed a soak in acid to completely clean off the junk on the lenses, but came out clean and usable.

[Louis D]

If you do decide to keep it, regardless of cleaning it, document the undisclosed fungus with macro photos clearly showing it and demand a commensurate refund of part of the purchase price as compensation for your troubles.

[jonathan]

I'm curious about the UV cure - I have read on these forums a time of about 20 minutes, but is that direct sunlight shining through glass itself or is scattered UV sufficient, e.g. eyepiece laying on it's side?

If working with lens elements or OTA glass or mirror surfaces etc I would recommend a bulb blower (with long plastic nozzle) to blast away dust and small particles etc, I could only find a medium-sized one which I bought from eBay, I wanted a much larger version (the bulb itself the size of my hand) but couldn't find where to buy one from.  I've seen advice not to use an air duster as this can spew out liquid propellant.

[DaveL59]

2 hours ago, jonathan said:

I'm curious about the UV cure - I have read on these forums a time of about 20 minutes, but is that direct sunlight shining through glass itself or is scattered UV sufficient, e.g. eyepiece laying on it's side?

If working with lens elements or OTA glass or mirror surfaces etc I would recommend a bulb blower (with long plastic nozzle) to blast away dust and small particles etc, I could only find a medium-sized one which I bought from eBay, I wanted a much larger version (the bulb itself the size of my hand) but couldn't find where to buy one from.  I've seen advice not to use an air duster as this can spew out liquid propellant.

hi Jonathan, ideally you'd not have the sun directly aiming into the lens as mentioned elsewhere. Risk of heat damage and of course potential to start a fire if the sun gets focused onto something thru the lens. Offset from the sun so that diffuse UV can flood the component should be fine. It will only kill fungus tho, not remove it, so while it will prevent spread you'd need to strip things down to clean the surfaces if you felt it worthwhile. HTH

[Don Pensack]

15 hours ago, jonathan said:

I'm curious about the UV cure - I have read on these forums a time of about 20 minutes, but is that direct sunlight shining through glass itself or is scattered UV sufficient, e.g. eyepiece laying on it's side?

If working with lens elements or OTA glass or mirror surfaces etc I would recommend a bulb blower (with long plastic nozzle) to blast away dust and small particles etc, I could only find a medium-sized one which I bought from eBay, I wanted a much larger version (the bulb itself the size of my hand) but couldn't find where to buy one from.  I've seen advice not to use an air duster as this can spew out liquid propellant.

Use a rubber ear syringe.  It will satisfy your size requirements and they concentrate the blast in a very small area.