PDA

View Full Version here: : Dont Be Afraid of Filters


leon
13-06-2008, 02:47 PM
Hi guys, (THIS IS MY OPINION ONLY DO NOT TOUCH YOUR FILTERS)

Well, well, well, we have been had, yep, when it comes to cleaning and touching filters, we are told, :scared: :scared:

Not true, as some of you know I dismantled my 5D and replaced the filter with a UV/IR, scary stuff, but it worked. ;)

The filter I removed, was not going to be used again, it was in excellent condition before I removed it, but took a battering whilst being removed, please see broken edges and chips :lol:

So, to make it more interesting I thought I would test this coating of which they speak, never to be touched, :scared: or brushed, :scared: or whatever.

Firstly I smeared it with black SticaFlex silicon, let it cure over night, then dropped it into a bath of mineral turps the next day to see if it would dissolve the silicon, it would not, :mad2: even after a good brushing with the paint brush. :shrug:

Ok, I said maybe Acetone will shift it, put some on a rag, and boy did it shift it it was gone, after a good hard rubbing with the stuff, ;) then sprayed it with Metho, to freshen it up, washed it under the hot tap, dryed it with a tea towel, and finally with a lens pen.

And here is the result, not a mark, scratch, or blemish on it. :thumbsup:

So I reckon, clean your stuff, and don't be afraid to touch, and clean again.

However, (THIS IS MY OPINION ONLY DO NOT TOUCH YOUR FILTERS)

Check out the images below, first and second both sides of the filter, the next two with a flash through the filter, as you can see not a make on it.

Oh, by the way, I had this under a Loupy,

Leon :thumbsup:

Robert_T
13-06-2008, 03:22 PM
Thanks Leon, there's a pesky piece of grunge on my $200 IDAS-LPS filter that I've been wanting to take to with a steel brush for weeks... now I feel released to do my worst:P:rofl:

leon
13-06-2008, 03:41 PM
Robert, don't be afraid, be gentle, it will be fine, if not, and you stuff it up, I will buy you a new one, promise, ;)

Leon :thumbsup:

wavelandscott
13-06-2008, 06:31 PM
"So I reckon, clean your stuff, and don't be afraid to touch, and clean again"


While I have had no experience with cleaning filters...or other high end optics other than my own TV and Pentax eyepieces but I reckon this statement by Leon is right on track with my own beliefs...

Be gentle and use common sense but don't be afraid to clean your astro gear if/when they need them...

Clear Skies...

Zuts
13-06-2008, 07:29 PM
Hi,

I wont say which telescope shop did this as I dont want to start an argument.

I went down and asked how i could carefully clean my C11 corrector plate and they gave me a demo on a SCT they had. They simply soaked a tissue in cleaning solution and then gave the corrector a hearty rub all over. The glass became very clean and the job was done in under a minute.

No scratches, no problems. They said it's a telescope, not a baby and within reason treat it like it is, a well made robust instrument. The coatings are extremely tough and impossible to remove with a tissue.

Paul

leon
13-06-2008, 08:11 PM
Dead right Paul, the coatings are tougher than the glass they are on, my experiment was to the extreme, so guys don't worry, you can not damage the coatings of a filter with care.

Leon

OneOfOne
15-06-2008, 02:55 PM
Yes, I tend to agree...so long as you are careful you will probably find the coatings much tougher than you think. I guess we are probably concerned with what might happen if we tried cleaning a lens or corrector and if was softer than we think...I guess the best thing is to give it a try (on someone elses scope?)

Now cleaning a mirror may be a different case as they don't have the sort of coatings they put on lenses.

leon
15-06-2008, 05:00 PM
No one in there normal mind would treat a filter like I did in this experiment, I gave it a good flogging, and abused it to the extreme.

The point is, it is OK to clean and touch.

leon

cjmarsh81
15-06-2008, 06:54 PM
I have always been worried about cleaning my filters and mirrors. At least now I know if I am careful there shouldn't be a problem.