Museum Glass turns "blue"

Jack Flynn

CGF II, Certified Grumble Framer Level 2
Feb 19, 2004
Monterey, VA
Customer came in bringing new work. While here she mentioned that some museum glass (about 16 x 20) I used on one of her pieces last fall gives off a blue color at night when the lamps in the room are on. So distracting she doesn't want me to use museum glass on a shadowbox I'm doing for her now. I mentioned there was some new low-iron glass, as well as museum acrylic and that I'd look to see if that will solve the problem. Before I get with Tru-Vue thought I'd run it by the Grumblers. Any similar experience....or suggested remedies? Thanks.
I had a batch of Museum Glass from way back when that developed some weird surface traits. One of them came back to me recently and the glass had changed dramatically. The client, in attempts to clean the glass had used progressively agressive methods until the coatings were all but worn off.
They are aware of the nature of the product and have been using it for years with no problems.
I had a piece on some of my photo collection that went bad as well. I simply replaced the defective product.

There was a period when TV stopped production of the Museum Glass. The pieces that I had go bad were from before that time.
I'm happy to replace her glass, that's a good solution I hadn't thought of yet. She has reduced confidence in the product and doesn't really want me to experiment in her house, just inclined to go with con clear glass. In the event the glass used was defective, is it a mistake to use a new piece from the same box or shipment as a replacement? Do you think these were batch issues as opposed to a single bad lite?
I am sure someone will post a scientific explanation of why this is. All I have for you is...haven't you seen the way light reflects in museum glass? It always has a colored reflection. It's reflection is reduced for sure but the light that is reflrected has a color cast to it that isn't natural. This is why I have to explain to my clients to properly light the art to avoid these odd reflections. I one time thought that I was doing them a favor by comping them museum glass over con clear. They took it home and promptly called me up and told me they hated it and they couldn't stand the way it looked in the lighting area it was in. I like the stuff but it does still have limitations.
I have also noticed a blue tint on some of my museum glass pieces, but we don't have the opportunity to use it all that often. I have been very happy with Perfect Vue glass. It still has that little haze that CRC gets, but not nearly as bad.

I'm not all that impressed with the low-iron stuff. It seems to be very flimsey.

We were just discussing DenGlass water white glass. It has no tint. I hear it is excellent, but also a little high up on pricing. You may want to check that out.
Donna, water white is beautful stuff, BUT it isn't UV protection. They do have a UV Water White, but even more expensive!
If this reflected color cast is a naturally occurring effect of the museum glass, then it is not as suitable for all the applications I previously thought.

Briank: Thanks for pointing out that it happens in different ways, with different lighting. Customers most dislike unpredictable outcomes, so I'll learn more about this before selling it up.

Donna: My distributor rep tells me that eventually all TV will be low-iron. Do you know if that is the case, which wouldn't be good if it is flimsy...

Bob: UV Water White...more expensive than regular water white, or more expensive than TV museum glass?

Thanks all.
We haven't experienced the "blue" but it seems like almost every time we get museum glass the coated surface appears imperfect. There are usually small circles that you can see if you hold up the glass to light. Does anybody know what I am talking about?

Yes. More expensive than both. My distributor lists it at $256 for a case of 3 32x40.


the "flimsy" glass is probably 2 mm and not 2.5 mm. The TV I am getting now is low-iron and I believe it is 2.5mm. I haven't had a problem with it "snapping" on me when I flip big pieces. (Thankfully!)

I really avoid the thin stuff. It just breaks too easy for my liking.
Talk to your distributor if you haven't checked DenGlas pricing in a while...

Mine sells 32 X 40 (3) at $219.60. #DGUV3240 DenGlas UV filtered. I used it and like it.

Are you possibly refering to the UV Laminated Water White DenGlas?

Dave Makielski
If artwork is lit properly, AR glass will not show those blue/green/purple reflections. Folks who are that sensitive to reflections should hire a professional lighting designer as well as spring for the AR glass. It can make all the difference.

edie the glarewhatglare goddess
Anti-reflective coatings on glazing work on the
basis of reflections being cancelled. The coating
comprises layers of metallic oxides and silicates,
which cause the out going reflection to be opposite in phase with the incoming light, so the
reflection is cancelled. This effect works over a
range of roughly 60 degrees and it can be overwhlemed by a light source. The modified reflections one sees from light sources will be
either violet or blue/green depending on how the
coatings were engineered.

"This effect works over a range of roughly 60 degrees and it can be overwhelmed by a light source."

Unsure what "range of roughly 60 degrees" refers to...but assume the fix is more involved than moving the lamp..or is it? Is the 60 degrees referring to the angle of the reflection, or is it an arc that relates to the face of the frame? Whew, I'm confusing myself with my questions.....
The less iron in the glass, the less "hard" the glass, and the less "green" the glass. An absence of iron, or waterwhite, results in a very soft glass (it's all relative). The "flimsy" nature of the lower iron glass is to be expected.

Denglas products are competitively priced when comparing like product. They have been researching the waterwhite/UV/anti-reflective laminate product off and on for quite a while, but I was unaware they had put it into production at any point. A like product is produced by Schott Glass of Germany and is available through Museum Glazing Services in Maryland.
Originally posted by Dave:
Talk to your distributor if you haven't checked DenGlas pricing in a while...

Mine sells 32 X 40 (3) at $219.60. #DGUV3240 DenGlas UV filtered. I used it and like it.

Are you possibly refering to the UV Laminated Water White DenGlas?

Dave Makielski
Yes Dave, and sorry I didn't answer soopner, but I was referring to the UV Water White. The Water White is listed at $213.60 for 32x40 3 lites per case.

They also have a UV Den Clear, which is similar for an ultra low iron TV UV and it is listed at $75 for 32 by 40 6 lites per case.

These prices are off DonMar's web site, I have rarely paid these prices, they are usually lower than that. I was using the UV Den Clear for a while, but they didn't have the little UV stickers, and my habit has been to default to TV ConClear when I order, so I have fallen back to uing the TruVue brand again! Just habit both are really good glasses.