Eyepiece smudge, Cleaning Advice

[209herschel (Herschel)]

Hi everyone,

I have a GSO 10" undriven dob.

I recently started using a TMB Planetary II 9mm. I'm really happy with the added FOV over my 9mm GSO plossl. The only issue is that I think there may be a smudge or some residue on the lens. When viewing Saturn, as it drifts into the middle of the field, I see a ghosting of the image. So it's like a hazy trail coming off the image. Is this likely a smudge or some oil residue on the lens? I was going to buy some Bintel cleaning fluid or some alcohol based fluid from bunnings tomorrow and gently use a cotton bud to clean the lens. Is this a good method?

Holding a light up to it, I definitely see some marks on the lens. If not a smudge, is there anything else it could be? The reason I think a clean might work is because when I replace the TMB with my 9mm plossl, the image clears significantly and there's no ghosting.

Thanks in advance,
Herschel.

[MortonH]

I'd simply try breathing on it and wiping gently with a soft, lint-free cloth or tissue (as long as the tissue isn't 'medicated' with aloe vera or something).

[leon]

First try and get any dust off with a blower or similar then just use a good Lens Pen, they work brilliantly

Leon

[209herschel (Herschel)]

Originally Posted by leon

First try and get any dust off with a blower or similar then just use a good Lens Pen, they work brilliantly

Leon

Actually, Bintel have a lens pen for around $20 so I might look into that before trying the cotton bud with the fluid. Thanks very much.

[leon]

And the thing about the Lens Pen they work over and over again.

Leon

[Renato1 (Renato)]

I use a big blower and then lens cleaning paper and a drop of lens cleaning fluid sold in photographic shops. If need be, I wrap the paper around an ear bud to get to an internal area.

As for cotton, I've read in several American articles that cotton balls and the like should be avoided, as when processed, little impurities can get into it.

What you describe certainly sounds like what I get on my short eye relief eyepieces when my eyelashes smear them. Strange it should be on your TMB.
Regards,
Renato

[Don Pensack]

I hate to be a contrarian, here, but lens pens are just about the most common way eyepieces get scratched:
--they're only clean once, and from then on they're smearing oils and residue picked up from the last cleaning.
--they leave a powdery residue on the lens (don't believe me? look with a loupe)
--they drag dirt particles around and around on the lens.
You should not use a lens pen--ever! Unless you don't really care about scratches.

Use pure isopropyl alcohol and Q-Tips: blow off the dust with a blower bulb, make a spiral pass from the center out with a q-tip moistened with alcohol (couple drops will do it), then flip the q-tip over and repeat the pass with the dry end. Grab a 2nd q-tip and clean up any spots left on the lens.
See: http://www.televue.com/engine/TV3b_page.asp?id=103

After cleaning, check again. It's possible there's a scratch on the lens, and it's possible the eyepiece has some internal reflections. If, as you watch, a ghost image comes in opposite the bright image, crosses in the center, then exits the side opposite the bright image, it is probably an internal reflection sometimes referred to as "ghosting".

[sn1987a (Barry)]

Yep that's how I do mine. This is what Televue recommends and they oughta know.

[leon]

Sorry guys I don,t agree, a decent Pen works very well, I have been doing it for years, I even clean the Canon 5D sensor with one, not an issue at all.

The lens coatings and sensor filters are tougher than lead to believe, and one can clean with confidence.

Leon

[Don Pensack]

Try looking at the surfaces with a loupe.

[casstony]

Anything that applies pressure to the optical surface while cleaning is asking for trouble - best to let a solvent do the work for you, then use tissue, cotton balls, etc to gently remove the dissolved contaminants.

I don't even use q-tips for eyepiece cleaning since it's possible to apply too much pressure if one becomes impatient. I roll a Kleenex tissue tightly into a pencil shape then tear it in half leaving soft ends on the two halves - I can't apply pressure because the tissue bends. Dip one end in isopropyl, clean the lens then spin the tissue around using the dry end to absorb the solvent before it dries.

[MortonH]

Here's an instructional video on eyepiece cleaning that is also fun to watch

https://www.youtube.com/watch?v=v3vWB5EgG_Q

[LewisM]

I am in the process of restoring a VERY neglected refractor. I cleaned the objective, after removing the dirt and crud with a blower first, with my Windex/acetone/ethanol solution. This cleaned it 95%. I then followed up with reagent grade acetone - just as TV suggest - applied with lens cleaning paper (whilst wearing cotton gloves) and then the entire lot wiped clean with several lens papers. Spotless.

The lens pen is good for UV filters on cameras, and I admit I will use it on finders (I cleaned up a neglected Takahashi 6x30 today with one), but NEVER on an EP, objective or binocular lens. They simply retransfer old oils etc as mentioned previously, and being carbon based, no real way to effectively clean them before a reuse. They DO leave carbonaceous deposits on the surfaces "cleaned" with them - as also mentioned, get a loupe or magnifying glass and have a look - you'll be surprised!

[Suzy]

Originally Posted by casstony

Anything that applies pressure to the optical surface while cleaning is asking for trouble - best to let a solvent do the work for you, then use tissue, cotton balls, etc to gently remove the dissolved contaminants.

I don't even use q-tips for eyepiece cleaning since it's possible to apply too much pressure if one becomes impatient. I roll a Kleenex tissue tightly into a pencil shape then tear it in half leaving soft ends on the two halves - I can't apply pressure because the tissue bends. Dip one end in isopropyl, clean the lens then spin the tissue around using the dry end to absorb the solvent before it dries.

I really like this idea, Tony Thanks!
I would've thought a tissue would give off lint tho, but obviously not. I'd still use the blower after it anyway, so perhaps it doesn't matter at all.

Don, that's really interesting what you said about the lens pen- I've always had my reservations about this too. What's a loupe please?

Herschel, I find the Bintel solution does a better job than the lens pen. Many times I've gone to use the lens pen and the smudges won't come off and they do with the Bintel fluid. I guess it depends how dirty & set in the smudge is.

Can lens wipes (the ones for cleaning glasses) be used???

[casstony]

Forgot to add that after I roll the tissue into a pencil shape I twist it a few times, then when it's torn in two the ends stay wound up.

[PeterEde (Peter)]

A finger print is 100% oil with a few specks of dead skin maybe. Why not a few drops of isopropyl alone as a flood irrigation?

[Suzy]

From what I've heard about Bintel's formula, they use a dash of Windex. It's apparently dubbed fondly as "Bintel Juice"
It does a super job. Though I haven't compared it to just straight isopropyl.

[casstony]

Originally Posted by PeterEde

A finger print is 100% oil with a few specks of dead skin maybe. Why not a few drops of isopropyl alone as a flood irrigation?

With the sealed ES eyepieces you can sit a few drops of Isopropyl on the eyelens for a minute then flush it under the tap, but fluid could easily end up inside a Televue using the 'irrigation' technique.

[209herschel (Herschel)]

Thanks for the advice everyone. I tried the Isopropyl alcohol and cotton buds I got from Bunnings and while it may be my technique, I couldn't get this to work. It seemed to always leave streaks. I actually picked up some lens wipes from Bunnings (Morgan's lens cleaning wipes - 99c for a box) and it was the best thing so far. Just a bit difficult to get to the very edge but really no streaks at all. Then I went to Bintel because I thought I'd get the lens pen as a final tool and they said they recommend their solution with a tissue. I'll try that this afternoon. They seemed to say the lens pen wasn't their preferred method.

Thanks again,
Herschel.