Lense cleaning

Is it true that a 50% solution of 99% isopropyl alcohol and distilled water
(1:1) makes
a good lense cleaner? Does it affect coatings?

cut the 99% alcohol to 40% and add 10% filtered windex plus one drop only of
photo flo .....filter it all using coffee filters. Its easy on coatings and
wonderful lens cleaner - fully tested by several obsrvatories of note. Maybe
someone has a better one?

Ive always wondered what Chris recommends? Have never seen him
post on this but he must recommend something for his fine apo's ?



MD wrote:

Is it true that a 50% solution of 99% isopropyl alcohol and distilled water
(1:1) makes
a good lense cleaner? Does it affect coatings?

I've used pure isopropyl on filters without any problems. Note that
the isopropyl you get at the drug store isn't all that pure. I use
technical grade (about twice the cost, but no wintergreen oil or other
mystery stuff in it.] I get my technical grade isopropyl at Fry's
Electronic, but I found an old post right on s.a.a. that says Radio
Shack sells it as well.

At Fry's, look for PureTronics Technical Grade Isopropyl alcohol,
99.9% ultrapure. $6.99 for 32oz. Like I said, not cheap.
http://www.puretronics.com/distributors.htm

Cotton balls are considered better than lens cleaning paper. Generally
the procedure (at least for filters) is to blow off the dust, then use
a cottonball dipped in the alcohol to do the first wipe, then toss it
and get a clean cotton ball and repeat. What you are trying to do is
not to rub the surface of the glass with dirt. I have a scuba tank of
compressed air (relatively cheap if you use canned air in volume). I
you use the air from a canned duster, make sure you keep it level so
none of the refrigerant flys out. The claim is the cold refrigerant
could disturb the glass surface.

Lumicon has filter cleaning tips here. No mention of diluting the
alcohol.
http://www.lumicon.com/faq-c.htm




"MD" wrote in message news:xyard.213354$df2.119733@edtnps89...
Is it true that a 50% solution of 99% isopropyl alcohol and distilled water
(1:1) makes
a good lense cleaner? Does it affect coatings?

These 2 responses help much. Thanks.

"pol haut" wrote in message ...
cut the 99% alcohol to 40% and add 10% filtered windex plus one drop only
of
photo flo .....filter it all using coffee filters. Its easy on coatings
and
wonderful lens cleaner - fully tested by several obsrvatories of note.
Maybe
someone has a better one?

I would go the other direction --- less water. Acetone also makes a great
cleaner, especially after the alcohol.

Ive always wondered what Chris recommends? Have never seen him
post on this but he must recommend something for his fine apo's ?

See:
http://www.astro-physics.com/index.h...care_refractor

Clear Skies

Chuck Taylor
Do you observe the moon?
Try http://groups.yahoo.com/group/lunar-observing/

Are you interested in understanding optics?
Try http://groups.yahoo.com/group/ATM_Optics_Software/

************************************



MD wrote:

Is it true that a 50% solution of 99% isopropyl alcohol and distilled
water
(1:1) makes
a good lense cleaner? Does it affect coatings?

I'm not so sure about using any windex. First, it has ammonia, which
is known to etch some coatings. Second, it has that blue dye.

Photoflo will insure no spots are left. If the alcohol doesn't get
diluted, then you won't have spots because alcohol will evaporate. The
caveat is I've only used the pure alcohol on filters, and maybe lenses
are different.

pol haut wrote in message ...
cut the 99% alcohol to 40% and add 10% filtered windex plus one drop only of
photo flo .....filter it all using coffee filters. Its easy on coatings and
wonderful lens cleaner - fully tested by several obsrvatories of note. Maybe
someone has a better one?

Ive always wondered what Chris recommends? Have never seen him
post on this but he must recommend something for his fine apo's ?



MD wrote:

Is it true that a 50% solution of 99% isopropyl alcohol and distilled water
(1:1) makes
a good lense cleaner? Does it affect coatings?

See:
http://www.astro-physics.com/index.h...care_refractor

Clear Skies

Chuck Taylor

Chuck:

Thanks for the link, its a good one. I especially agree with the last line:

"Excessive cleaning is to be avoided."

I see forums where people seem to recommend cleaning mirrors as soon as the
dirt is visable, that makes me cringe...

jon

Let me look up the exact formula and I'll get back but the windex is
a component.



miso wrote:

I'm not so sure about using any windex. First, it has ammonia, which
is known to etch some coatings. Second, it has that blue dye.

Photoflo will insure no spots are left. If the alcohol doesn't get
diluted, then you won't have spots because alcohol will evaporate. The
caveat is I've only used the pure alcohol on filters, and maybe lenses
are different.

pol haut wrote in message ...
cut the 99% alcohol to 40% and add 10% filtered windex plus one drop only of
photo flo .....filter it all using coffee filters. Its easy on coatings and
wonderful lens cleaner - fully tested by several obsrvatories of note. Maybe
someone has a better one?

Ive always wondered what Chris recommends? Have never seen him
post on this but he must recommend something for his fine apo's ?



MD wrote:

Is it true that a 50% solution of 99% isopropyl alcohol and distilled water
(1:1) makes
a good lense cleaner? Does it affect coatings?

BTW, photoflo doesn't vaporize. Rather, it coats. You can find
threads on how to clean tanks coated with photoflo such as
http://www.photo.net/bboard/q-and-a-...?msg_id=0037Vk
That is, photoflo coating is well known by those who develop film.
[Well, maybe not well known enough since people do ruin tanks with the
stuff.]

I think the idea behind using anhydrous isopropyl is that it will
evaporate quickly (under reasonable temperatures) and not leave spots.
That is why I question adding other substances.

Note that when cleaning a lens you always wet the cotton or paper
rather then apply the fluid to the lens. This reduces the risk of
fluid creeping into the lens.




jerry warner wrote in message ...
Let me look up the exact formula and I'll get back but the windex is
a component.



miso wrote:

I'm not so sure about using any windex. First, it has ammonia, which
is known to etch some coatings. Second, it has that blue dye.

Photoflo will insure no spots are left. If the alcohol doesn't get
diluted, then you won't have spots because alcohol will evaporate. The
caveat is I've only used the pure alcohol on filters, and maybe lenses
are different.

pol haut wrote in message ...
cut the 99% alcohol to 40% and add 10% filtered windex plus one drop only of
photo flo .....filter it all using coffee filters. Its easy on coatings and
wonderful lens cleaner - fully tested by several obsrvatories of note. Maybe
someone has a better one?

Ive always wondered what Chris recommends? Have never seen him
post on this but he must recommend something for his fine apo's ?



MD wrote:

Is it true that a 50% solution of 99% isopropyl alcohol and distilled water
(1:1) makes
a good lense cleaner? Does it affect coatings?