Pollen on Tak 100DL Lens

[jock1958]

Looks like I have lots of pollen or dust deposits stuck on the outside surface of my Tak 100DL objective lens.

Have tried the standard blower but no joy. Should I leave well alone and not obsess or try cleaning it off with obvious risks involved?

Any advice on this will be greatfully received ?

 

 

 

[Ben the Ignorant]

You call that lots of pollen? That's not lots of pollen! THAT is lots of pollen:

 

[ollypenrice]

You should certainly clean it off. This is a perfectly simple process using something like Baader Wonder Fluid or a proprietory lens cleaning fluid from an optician. I give the lens a little squirt with the fluid first to let it soften the contaminants and then use short curved wiping motions, never re-using the same part of the cloth in case it has picked up grit. Unlike aluminium mirrors, lens coatings are actually very hard but organic matter can chemically degrade them, so there is a greater risk in leaving it on than in wiping it off. I'm not one for cleaning mirrors till they really need it but the word from the professionals I know is that organic matter can be bad for lens coatings.

If you end up with the mild 'oily swirls' look just ignore it. This wont affect anything.

Olly

[jock1958]

Eek ? that lens is a mess!!

Maybe I’m worrying over nothing, you’ve made me feel a lot better now!  Thanks 

[jock1958]

Thanks Olly, I probably made it look worse than it actually is by shining a torch across the lens when I took the pics 

[mikeDnight]

If it were mine I'd give it a clean. If you blow off any loose dust then use a "Solvent Free" lens cleaner and lens cleaning cloth, you'll be fine. Spray the fluid onto the cloth not onto the lens, just incase some gets between the elements. 

[Stu]

Have a look at this thread @jock1958, I've been through the same trauma 

Good luck! I think the main risk is leaving grit on the objective and that causing scratches. New cloth every time too!

 

[jock1958]

Thanks Mike & Stu will proceed with extreme caution, I don't want to make things worse and ruin my 60th birthday pressie! 

 

  

[Peter Drew]

Or get some trained bees.   ?

[paulastro]

DON'T put the lens under a tap and run water onto it !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!  You think no-one would ever do this?  Wrong.  I know someone who did this, except it wasn't a Takahashi 100DL - it was a Takahashi FS128   ?.

[mikeDnight]

7 minutes ago, jock1958 said:

Thanks Mike & Stu will proceed with extreme caution, I don't want to make things worse and ruin my 60th birthday pressie! 

 

  

After reading your thread on cleaning an FC lens, I thought I'd just check my objective. It did have a few particles of dust and one or two dew spots. I normally blow dust off the lens at the end of each observing session, so I wasn't surprised the objective was looking healthy. However, I thought I'd give the lens a light clean using only my breath and an optical microfiber lens cloth. A couple of breaths and gentle wipes brought the objective back to its mint condition. The 30mm finder however, was covered in pollen dust. Obviously I forget to blow dust off the finder objective, but with a little optical fluid on my lens cloth the finder is now pristine too. ?

[mikeDnight]

6 minutes ago, paulastro said:

DON'T put the lens under a tap and run water onto it !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!  You think no-one would ever do this?  Wrong.  I know someone who did this, except it wasn't a Takahashi 100DL - it was a Takahashi FS128   ?.

Beggars belief doesn't it!? 

I knew a chap who boiled his 3" Swift F15 objective to death. I never let him near any of my Taks! 

[F15Rules]

57 minutes ago, paulastro said:

DON'T put the lens under a tap and run water onto it !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!  You think no-one would ever do this?  Wrong.  I know someone who did this, except it wasn't a Takahashi 100DL - it was a Takahashi FS128   ?.

(To the tune of Shaggy song..) "It wasn't me.."

[ollypenrice]

1 hour ago, mikeDnight said:

If it were mine I'd give it a clean. If you blow off any loose dust then use a "Solvent Free" lens cleaner and lens cleaning cloth, you'll be fine. Spray the fluid onto the cloth not onto the lens, just incase some gets between the elements. 

Yes, I'm aware of this point and agree that you shouldn't let it get between elements. On the other hand it is routine for lenses to build up dew so the cells must be reasonably water tight. If they weren't I think there would be clear evidence of fungal growth in no time. I can see the case for applying the fluid to the cloth, though.

Olly

[Alien 13]

12 minutes ago, ollypenrice said:

Yes, I'm aware of this point and agree that you shouldn't let it get between elements. On the other hand it is routine for lenses to build up dew so the cells must be reasonably water tight. If they weren't I think there would be clear evidence of fungal growth in no time. I can see the case for applying the fluid to the cloth, though.

Olly

I am not sure they are, I have separated lots of old achromatic doublets just by soaking them in water for a few days, I expect its because the cement eventually dries out and becomes porous.

Alan

 

[ollypenrice]

1 minute ago, Alien 13 said:

I am not sure they are, I have separated lots of old achromatic doublets just by soaking them in water for a few days, I expect its because the cement eventually dries out and becomes porous.

Alan

 

Point taken. Get a scope wet enough and it will, of course, let water in. This happened after a roof automation failure to a friend's Tak FSQ and it got water inside, leading to fungal growth. It was successfully cleaned and recollimated by Optique Underlinden, fortunately.

Olly

[Alien 13]

3 minutes ago, ollypenrice said:

Point taken. Get a scope wet enough and it will, of course, let water in. This happened after a roof automation failure to a friend's Tak FSQ and it got water inside, leading to fungal growth. It was successfully cleaned and recollimated by Optique Underlinden, fortunately.

Olly

I had a an old pair of binoculars that showed what looked like fungal growth on one of the objectives but was in fact moisture damage to the cement. I used the water bath method on it and the unaffected lens and split them, made a couple of very thin shims and air spaced them, they worked like new.

Alan

[Tyson M]

Definitely don't run the objective lens in cell under a tap. I did this once with a Vixen 102SS that I received with a super dirty lens. Soap solution got trapped between the lens and it was a nightmare to take apart and clean properly to fix. Ultimately, I chipped the lens reassembling it. 

Takahashi states while cleaning, to be very careful about excess water / solution towards the edges of the lens. Capillary action can transfer it inside beyond your reach, then it is an expensive/risky shipping trip to get fixed.

 

Also, I agree with others to clean the pollen asap. Gently cleaning should be a routine procedure and pollen can damage coatings over time. 

 

[jock1958]

Well bit the bullet and cleaned my lens and am pleased with results.

Started off with a blower then an extremely soft 1” artist brush to remove any loose dust deposits.

Then with extreme care I used two Baader cloths, first to apply the Wonder Fluid second to polish off.

There were a few streaks that I huffed and polished off.

IMO the Tak lens coatings must be  pretty tough and durable but I won’t be making a habit of having to clean it, I need to keep an eye out for that pesky pollen and in between viewing sessions use the lens cap.

General consensus from your comments and dealer where I bought it, is to remove pollen before it can permanently damage the coatings.

[Cleetus]

How does the pollen get there in the first place?

[jock1958]

40 minutes ago, Cleetus said:

How does the pollen get there in the first place?

My back gardens not that big and surrounded by a variety of trees so I’m assuming it came from them, if it is the tree pollen I’m not sure when and how it happened but it’s something I need to look into.

[Tyson M]

Looks great, excellent cleaning job.  Coatings are surprisingly robust but ultimately it is a good idea to remove anything besides dust or dew spots, especially with a scope like a Tak.

I still remove dew spots or better yet dont let them form and harden in the first place. 

[paulastro]

I always use a blower (rubber bulb blower)  on my refractor before capping it and bringing it indoors.  I've done this for many years, as in the dark you can't necessarily see if anything is on your lens.  Prevention is always better than cure.  I do the same for eyepieces before packing them away.

[jock1958]

8 hours ago, paulastro said:

I always use a blower (rubber bulb blower)  on my refractor before capping it and bringing it indoors.  I've done this for many years, as in the dark you can't necessarily see if anything is on your lens.  Prevention is always better than cure.  I do the same for eyepieces before packing them away.

Thanks for advice. Agonised for ages whether it was a good idea to clean off pollen or do nothing, decided to take advice from you good guys and Tak dealer then clean it off. 

A tough lesson learned me thinks!!

[ollypenrice]

I perfectly understand the inclination to be precious but my increasingly elderly Takahshi FSQ 106, and its twin belonging to Tom O'Donoghue on our dual rig, are routinely cleaned using Baader fluid and a suitable cloth. This has been going on for years and will be going on for years to come, I'm perfectly sure.  And the message is... relax!

Olly