EP care

[Anweniel]

I've done a lot of reading lately regarding equipment, setups, processing etc

One thing I've come across a few times is the retention of quality in optics. As I understand dew, physical damage, zealous cleaning and fungus can seriously undermine the performance of my equipment, what preventative measures should I be taking to make sure that I get longevity out of my EP's?

Sorry if I missing something that is discussed in other topics:iamwithstupid: but mostly I only see discussion around suitability or this vs that.

Thanks for any advice in advance

[John]

My eyepiece care routine includes keeping them in a foam lined case with caps on both ends when not in use and only cleaning them when it's really required, using Baader Optical Wonder fluid and the Baader Micro Fibre cloth.

When observing I keep the eyepieces in the case and capped, until needed then return them there after use. The foam in the case tends to keep them at a little above outside temperature which seems to stop dewing / misting problems.

Eyepieces are generally quite robust though so should last years with a little care.

[Chris H]

Keep them capped when not in use, try your best to not touch the lenses (although often your eye lashes will brush them). When you want to give them a clean use a hurricane blower and Baader optical wonder fluid and micro fibre cloth.

[Chris H]

John types faster than I do.

[Anweniel]

Haha Thanks Chris and John. Of course I do these things anyway (except the cleaning part so far - felt that was far to bold and so soon unnecessary). As you know establishing an equipment set is expensive and maybe I am being overly cautious but I just dont want to be neglecting my kit

[newman]

Well, one thing you can do is to try to prevent the need to clean them in the first place - at least, as much as possible. Dust is easy, but preventing dew is also possible - there are anti dew heaters for both 1.25" and 2" eyepieces you might look into to prevent dew forming in the first place. These are basically resistors wrapped in water proof material, secured around your ep with attached velcro strips. Of course, these consume power so you'll need some way to power these heaters in the field - unless you already own a power tank you'll need to come up with a power source for these.

[twotter]

I keep my EPs in their case until I need to use them. So far I've never had an issue with dew affecting my EPs.

[newman]

Oh, it can happen. I was on a longer observing session 3 days ago (humidity levels were pretty high), and pretty much every lens I own, main aperture one, finder, telrad and eyepiece, all had dew on it after a few hours. I guess it may not have been such a problem on a smaller eyepiece but those 2" monsters have rather large glass surfaces so I guess dew forms easier on them. I definitely plan on getting an eyepiece heater strip after this.

[Anweniel]

Thanks Newman, I do have a power tank so i'll look into it

[great_bear]

Personally I don't bother with capping, since the entire eyepiece case is effectively one huge eyepiece cap. They have remained as clean as always under this regime, and there's a lot less "faff" involved.

There's three moisture problems that I've experienced in the past.

1. Dewfall
   
2. Fogging up in use
   
3. Misting over when not used
   

The first - dewfall - occurs when the eyepiece lid is left open at the exact time that the temperature drops and everything in the vacinity gets drenched in moisture falling from above. The time-of-day that this happens varies widely from just after nightfall until just before daybreak. I don't know if it is seasonally-related, but is avoided simply by keeping the eyepiece case lid closed.

The second - fogging up in use - is a tough one. It seems to happen if the space between your eye and the eyepiece is too enclosed - such as when using winged eye-cups. The trick is to back off a few millimeters and let the mist clear.

The third - misting over when not used - is the classic dewing problem in astronomy. It's simply that the eyepieces have over-cooled.

All of these issues are minimalised by keeping eyepieces in a well-padded eyepiece case which should remain closed until you need to swap over. This keeps in the residual warmth (from being stored in the house) and keeps all of these condensation-related issues at bay for the longest time.

The worst place to leave eyepieces is uncapped on a tray on the ground. They'll get dewed up very quickly this way...

[great_bear]

One other thing - don't overly-avoid cleaning. Greasy marks like fingerprints can get permanently etched into the coatings if not promptly wiped off.

[newman]

If I get really visible dew stains I get rid of them using optical cleaning fluid and a microfiber cloth. As for dust, I keep things capped when in storage. If I still notice some dust forming on any optical surface I use an air compressor and an empty airbrush to blow them clean. Much better than trying to get rid of dust with any sort of cloth.