Fungal Growth....... :-(

[Gogleddgazer]

On checking over my rig today I've discovered some fungal growth on the inner parts of the main objective cell in my APO triplet.  Suggestions from the SGL HIVE-mind for short term amelioration measures and perhaps more crucially recommendations/contact details for UK-based technicians who can disassemble, clean and re-collimate the OTA.  I am pretty practical but don't believe that I have the wherewithal to do a proper job on my own.  Thanks in advance.

J

[doublevodka]

https://www.firstlightoptics.com/adapters/astro-essentials-dual-fit-desiccant-cap-red.html to remove the moist air from the tube

UV light to kill any growth - https://www.amazon.co.uk/s?k=uv+torch&crid=CECT06WX5NUI&sprefix=uv+torch%2Caps%2C74&ref=nb_sb_noss_1

 

Telescope servicing - https://www.google.com/search?q=telescope+servicing+uk&rlz=1C1GCEB_enGB1054GB1054&oq=telescope+servicing+uk&gs_lcrp=EgZjaHJvbWUyCQgAEEUYORiABDIICAEQABgWGB4yCggCEAAYhgMYigXSAQg0MzEyajBqNKgCALACAA&sourceid=chrome&ie=UTF-8

Can't recommend one as never used one, but I'm sure someone will be along with recommendations soon 👍

 

[Carbon Brush]

+1 For a dry tube. Fungus won't grow in a dry place.

As for UV. Yes in principle. I do though defer to someone knowledgeable for details.
Long wavelength reduces risk of damage to rubber/plastic/paint.
Short wavelength is more likely to break chemical bonds in fungus - but increases the scope materials risk.
We have all seen paint fade, rubber cracking, etc. on non astro kit.
Someone somewhere presumably has knowledge of effective time, intensity and wavelength.

A furher consideration is temperature. I'm guessing fungal spores are very hardy. Though a growing fungus is not.
Maybe a visit to your freezer or a gentle (80C?) oven?
Again I defer to someone with more knowledge.

Watching with interest.

 

[dweller25]

7 hours ago, Gogleddgazer said:

On checking over my rig today I've discovered some fungal growth on the inner parts of the main objective cell in my APO triplet.  Suggestions from the SGL HIVE-mind for short term amelioration measures and perhaps more crucially recommendations/contact details for UK-based technicians who can disassemble, clean and re-collimate the OTA.  I am pretty practical but don't believe that I have the wherewithal to do a proper job on my own.  Thanks in advance.

J

Point your scope just BEHIND the Sun on a clear day as soon as you can, the UV will kill the mould.

The mould may have eaten into the coatings, which whilst not looking great will have no effect at all at the eyepiece or sensor.

Edited November 14, 2023 by dweller25

[Mandy D]

6 minutes ago, Carbon Brush said:

+1 For a dry tube. Fungus won't grow in a dry place.

As for UV. Yes in principle. I do though defer to someone knowledgeable for details.
Long wavelength reduces risk of damage to rubber/plastic/paint.
Short wavelength is more likely to break chemical bonds in fungus - but increases the scope materials risk.
We have all seen paint fade, rubber cracking, etc. on non astro kit.
Someone somewhere presumably has knowledge of effective time, intensity and wavelength.

A furher consideration is temperature. I'm guessing fungal spores are very hardy. Though a growing fungus is not.
Maybe a visit to your freezer or a gentle (80C?) oven?
Again I defer to someone with more knowledge.

Watching with interest.

 

254 nm UV is effective at killing bacteria and microbes. It is commonly referred to as UV-C. It is extremely harmful to human tissue, so zero exposure!!! It is also readily blocked by regular glass (soda glass), but is passed by silica (quartz). My last involvement with it was more than 20 years ago, in connection with pharmaceutical industry, so am very rusty. As you say, it is damaging to plastics.

[Gogleddgazer]

Thank you all for your inputs. I am investigating options to get the refractor serviced, RVO have the facilities and I have also tried to raise Es Reid who has come up in a number of threads/fora as something of a refractor fettling/collimation guru.  Fingers crossed. Once it is sorted the next question will be how to keep the tube dry with all the imaging gear attached in a ROR obsy!

[Astroscot2]

I had a similar problem a year or so ago with a triplet, leaving the scope pointing at the Sun was not an option for me as I live in Scotland,  I purchased a UV-C light based on recmommendations to stop the growth getting any worse which worked. I was able to get a hold of Es via another forum member, initiallly I had been advised by a vendor that Es was too busy to help as he had other commitments, this turned out not to be the case,  Es was able to clean and re-assemble the lens with which turned out to be quite a job (Skywatcher APO). He did a great job and I recommend him.

 

Mark