Why do we mount photographs behind glass?

[ageorge]

The experience is so much better without the glass in the way. Other framed art is presented without glass. So why do we? Sans Verre anyone?

[naturephoto1]

Glass or other glazing materials are used to protect the photo from dust, scratches, fingerprints (particularly for glossy papers), sunlight/UV, moisture, .....

Rich

[Bruce Watson]

Glazing protects the (fragile) print from touch and from environmental polution. Not to mention UV. In other words, it keeps the print and its mounting system clean.

You can show prints without glass. Nothing to stop you. That's one of the reasons I like inkjet printing on canvas. I can varnish the print and stretch it like a painting. The varnish protects the print from sticky little hands, UV, and all the rest so you don't have to show it behind glass. It makes a nice presentation IMHO.

[ageorge]

Glass or other glazing materials are used to protect the photo from dust, scratches, fingerprints (particularly for glossy papers), sunlight/UV, moisture, .....

Rich

Very expensive paintings are presented without glass. Would they not suffer from these same conditions? It seems to me that a photograph would be more robust than a painting that is several hundred years old, no? Is it just tradition to mount behind glass?

[Aender Brepsom]

I always frame my pictures without glass, even for exhibitions. I prefer it very much that way, because I don't like the reflections of the glas. The print itself is not that expensive. Should it get damaged, you can always print a new one.

[Oren Grad]

Very expensive paintings are presented without glass. Would they not suffer from these same conditions? It seems to me that a photograph would be more robust that a painting that is several hundred years old, no? Is it just tradition to mount behind glass?

Precisely. The interesting question is not why photographs are presented behind glass, but why paintings often are not. The environmental insults that we worry about with photographs are problematic for paintings too, though the degree of susceptibility to different types of damage varies with the specific materials used.

[Toyon]

Paintings definitely do suffer from being mounted without glass. Ask any restorer the problems with atmospheric pollutants, smoke and other contaminants that they must clean off periodically. On the other hand, in the environmentally controlled conditions of a museum painting are often presented without glass. The trade off is deemed worth it.

[Bruce Watson]

Very expensive paintings are presented without glass. Would they not suffer from these same conditions? It seems to me that a photograph would be more robust than a painting that is several hundred years old, no?

No. Painters have, for hundreds of years, varnished their paintings as the final step. Some kind of protection is needed between the outside world and the paint. Most modern painters use an archival varnish -- one that can be removed without hurting the paint underneath.

[Sal Santamaura]

The experience is so much better without the glass in the way...Not if one uses the right glass. Check out Tru Vue AR. It's coated to eliminate most reflections and, for the last few years, has used a low-iron substrate to eliminate any green cast (of the glass, not the coating). Unless a viewer is strongly illuminated, the experience is almost like no glass at all. I'm a satisfied customer not connected with Tru Vue in any other way.

[Oren Grad]

Not if one uses the right glass. Check out Tru Vue AR. It's coated to eliminate most reflections and, for the last few years, has used a low-iron substrate to eliminate any green cast (of the glass, not the coating). Unless a viewer is strongly illuminated, the experience is almost like no glass at all. I'm a satisfied customer not connected with Tru Vue in any other way.

Tru Vue AR is fabulous, as was the late, lamented Denglas. But it's very expensive.

[roteague]

I mount all of my prints behind, because I like the way they look and the way the prints are protected. Since all of my prints are silver prints, I worry about protecting the surface. I also use the Tru Vue glass - it is just wonderful.

[naturephoto1]

Tru Vue AR is fabulous, as was the late, lamented Denglas. But it's very expensive.

I prefer, for my best finished framed images to be behind Tru Vue Museum Glass which is even more expesive than even their regular AR glass but less expensive than the equivalent Denglas. I have found that when the lighing is placed properly for images behind Museum Glass there is very little reflection and the images almost look as there is no glass in the frame. Museum Glass allows 96% of the visible light to be transmitted, the images appear sharper, with better color and contrast. Additionally, Museum Glass will remove or block 97% of the UV light. My intent for Galleries is to either supply images unframed or framed in Museum Glass. For direct marketing to businesses and the public, they have a coice of Tru Vue Conservation Clear (UV) glass or Museum Glass.

Rich

[ageorge]

I mount all of my prints behind, because I like the way they look and the way the prints are protected. Since all of my prints are silver prints, I worry about protecting the surface. I also use the Tru Vue glass - it is just wonderful.

If I had a nickel for every time I heard "once behind glass, you won't notice the difference" implying that some subtle difference will not be noticed because the glass subtracts from the experience enough the negate the differences. This is my experience as well. There is some subtraction no matter how good the glass. My question is why do we do this? Many other forms of art are presented without being under glass, why should we. Most photographs are not sealed from the environment so pollutants can and do come into contact with the surface of the print. If it is to protect from finger prints, scratches or other physical contact, well I will just take my chances with all the other art. I would rather give my viewers the full experience.

[David_Senesac]

TruVU Museum glass or Acrylite OP-3 are both very expensive, especially for large prints I tend to market. Actually I only market rolled unframed prints and let the customer make that framing choice with their framing shop of choice. For my master prints I use for exhibit and display purposes, I prefer not using any glazing material not only for the purpose you noted george, but also because it is lighter logistically. ...David

[naturephoto1]

As has been mentioned, Oil Paintings are protected with a varnish. Acrylic paintings are sometimes not behind glass. However, most (or a high percentage) of acrylic paintings, water colors, pastels, charcoal are generally displayed behind glass. Therefore, it would appear that the majority of 2 dimensional types of art work is in fact displayed behind glass (or possibly acrylic- plexiglass),

Rich

[roteague]

There is some subtraction no matter how good the glass. My question is why do we do this?

That is true, but since all printing methods are not capable of conveying the true image as represented in the transparency, I don't see this as a big issue. Since I have no intention of offering any prints in ink (other than posters), I need someway to protect the prints themselves. Why? Because I want my images to convey a sense of quality - and this is what I think quality should look like.

[naturephoto1]

Additionally, my work is printed normally on Fuji Crystal Archive Glossy photo paper, but is available on the Fuji Crystal Archive Super Gloss and used to be printed on high gloss Ilfochrome. The Fuji Crystal Archive Photos are printed off of a Chromira (or if need be larger images off of a LightJet). Robert prints the same way and unless mistaken his work is also printed on the same paper. The Fuji Glossy and Super Gloss Crystal Archive and Ilfochrome high gloss papers are quite fragile and subject to scratches, dust, and fingerprints. These papers are best displayed behind glazing materials.

Rich

[roteague]

Rich is correct, we do use the same printing techniques and papers.

[ageorge]

That is true, but since all printing methods are not capable of conveying the true image as represented in the transparency, I don't see this as a big issue. Since I have no intention of offering any prints in ink (other than posters), I need someway to protect the prints themselves. Why? Because I want my images to convey a sense of quality - and this is what I think quality should look like.

So "behind glass" equates to quality. Actually for me, not behind glass is a better way to experience a print. When I am evaluating one of my prints, I don't get out a piece of glass and put it behind it, that would be silly. So why should I display them that way? I think behind glass is just what we are used to.

[Helen Bach]

Another vote for Tru-Vue Museum and the acrylic version, Tru-Vue Optium Museum. I'd love to be able to show my prints without glazing, and I've used the "I will replace any print damaged during the exhibition" argument only to be told, very politely, that that was unacceptable practice for the venue. I saw the light. In the right location and circumstances, however, I would show without glazing.

Between 'non-glare' (textured or etched surface to diffuse reflections, but not reduce them); 'anti-reflective' (coated surface that cuts down reflections, eg Museum and the even more expensive Optium Museum) and 'abrasion resistant' (eg OP-3 AR, for acrylic/'Plexiglass'; much cheaper than anti-reflective acrylic) there seems to be a lot of opportunity for confusion.

Best,
Helen

[scott_6029]

So, how much longer will a print last behind glass? VS. No glass? I am talking about pollutants. I priced museum glass and it was quite expensive.

Now, for some of my 'collectable' expensive photo's where I am concerned about damage (fingerprints, somthing getting on the print, etc.) I put those behind glass. But my images.....where I can make another one....

Boy, I see both sides of this one.....I guess you pop for the expensive glass to get closest to the 'best of both' worlds when you need to?

[roteague]

So "behind glass" equates to quality. Actually for me, not behind glass is a better way to experience a print. When I am evaluating one of my prints, I don't get out a piece of glass and put it behind it, that would be silly. So why should I display them that way? I think behind glass is just what we are used to.

That sounds fine. We all have our own sense of what constitutes "quality."

[Sal Santamaura]

It's important to understand that the UV-absorbing Museum versions of Tru Vue achieve their selective transmittance by adding a laminated plastic layer which, in my opinion, significantly degrades images. I use only the laminate-free "plain" AR.

In my opinion, for black and white fiber-based (FB) or chromogenic color prints that will be displayed indoors, there's no need to be concerned about UV. Commercially manufactured chromogenic papers already include UV filtering; black and white FB should not be affected by normal gallery levels of UV, even from halogen lighting, after that illumination passes through glazing. Of course, if direct sunlight hits the prints, UV is the least of one's problems.

[roteague]

It's important to understand that the UV-absorbing Museum versions of Tru Vue achieve their selective transmittance by adding a laminated plastic layer which, in my opinion, significantly degrades images. I use only the laminate-free "plain" AR.

Polarizing filters and the windshield in your automobile does this as well.

[naturephoto1]

It's important to understand that the UV-absorbing Museum versions of Tru Vue achieve their selective transmittance by adding a laminated plastic layer which, in my opinion, significantly degrades images. I use only the laminate-free "plain" AR.

In my opinion, for black and white fiber-based (FB) or chromogenic color prints that will be displayed indoors, there's no need to be concerned about UV. Commercially manufactured chromogenic papers already include UV filtering; black and white FB should not be affected by normal gallery levels of UV, even from halogen lighting, after that illumination passes through glazing. Of course, if direct sunlight hits the prints, UV is the least of one's problems.

Hi Sal,

Tru Vue does not use any lamination for Museum Glass according to their spec sheets. They claim that it is the only non-laminated conservation quality antireflective glass on the market. The glass is made using thin film coatings deposited onto the glass. A microscopic layer of silica based UV-blocking Agents (particularly for the 300-380nm range) is cured onto the surface of the glass. Tru Vue used to indicate that the coating blocks a minimum of 97%, they now say 98%. Both Museum Glass and the AR glass both have the Magnetron sputter coating for the Anti-reflective coating. AR Glass limits only 78% of UV.

See these links:

http://www.viratec.com/downloads/museum_glass22.pdf
http://www.ilovemuseumglass.com/aboutmuseumglass.asp
http://www.viratec.com/downloads/ultra_clear31.pdf

Additionally, there is concern for UV given off by fluorescent tubes in many places that may adversely affect photographs and other art work.

Rich

[Helen Bach]

Schott Amiran TN has the UV absorption layer in a lamination - it's also a 'water-white' glass with an anti-reflective dip coating. It may have a different name outside the USA - there is a large range of Amiran glass available. The lamination didn't seem to affect the image quality for the sample I saw. It's one of the most expensive glazing options. Being laminated does give it a degree of safety in the event of a break. Laumont here in NY offer it as a glazing option.

[Sal Santamaura]

...Tru Vue does not use any lamination for Museum Glass according to their spec sheets. They claim that it is the only non-laminated conservation quality antireflective glass on the market....Tru Vue used to indicate that the coating blocks a minimum of 97%, they now say 98%...That's interesting. Perhaps the samples my local framing shop has are not current, since what was apparently Tru Vue's former laminate is textured and visible without straining. Maybe the change of percentage happened when this new approach was implemented.


...Additionally, there is concern for UV given off by fluorescent tubes in many places that may adversely affect photographs and other art work...I remain convinced that chromogenic color prints and black and white FB prints behind "plain" glass are essentially immune from adverse UV effects when displayed in ambient fluorescent illumination. Other works, e.g. watercolors, are a different matter entirely. I have not researched inkjet prints, but would refer to Wilhelm for reliable data on them, at least as far as UV-susceptibility is concerned.


Schott Amiran TN has the UV absorption layer in a lamination - it's also a 'water-white' glass with an anti-reflective dip coating...Denglas used dip coating and always exhibited significant defects resulting in long searches for a suitable area to cut. Tru Vue AR's sputter coating seems to be much more uniform. Also, Tru Vue is 2.5mm thick as compared to Denglas' 2.0mm, a significant advantage in larger frames. I don't remember how thick the Schott Amiran TN is.


...It's one of the most expensive glazing options...Indeed. When checking several years ago I couldn't find anyplace in my region of the US where it was available to look at. The high price probably ought to be expected though, considering this is a heavy product shipped from Europe.

[naturephoto1]

Hi Sal,

I believe that I have been using the current product. I think there is a bit of "texture" to the outer coating- that is the silica coating. Perhaps you can notice a difference in clarity between the Museum Glass and the AR, but from what I have seen, when lit, I see no texture or loss of sharpness. I would have to make a comparison, but this is the closest that I have ever seen a glazed image look like one that is "naked". The clarity, color, sharpness and contrast is astounding for my Chromira output Fuji Crystal Archive Glossy paper (up to 30" X 37.5") shot on Velvia 50 and Provia 100 shot with my Linhof Technikardan 45S.

Rich

[alec4444]

This is a great thread. I too have been battling this question, though sadly not because of gallery exhibitions...rather in my hallway. The point of contention in my head has been this: If I put my prints behind glass (which they are) why am I bothering with expensive papers? Granted, it may give the restorer extra satisfaction to see it during the cleaning a hundred years from now, but otherwise that lovely coated emulsion I paid so dearly for is really quite hidden behind cheap or fancy glass, pending your preference.

So for those of you glazing your prints...can you tell the difference in papers when they're behind glass? Or perhaps to be more fair, can anyone else distinguish the difference in your papers behind glass? :)

--A

[naturephoto1]

Alec,

The Acid Free Boards will not only last longer but the beveled cuts (acid board beveled cuts will yellow) should stay white for hundreds of years. Depending upon the photo paper you are using you should select Buffered or Non-Buffered Boards. The difference in cost between the "cheap" boards with acids versus Acid Free is small enough to not be a question in mind for anything that you want to last. I have friends that are custom framers or run frame shops/galleries. They have seen too often artwork including Dali, Shegal, Picasso limited edition prints prepared with cheap acid boards that were burned by the acids.

Rich

[roteague]

If I put my prints behind glass (which they are) why am I bothering with expensive papers?

Would you buy a Porsche and put a VW beetle engine in it?

[Steven Barall]

It's customary to frame with glass many different types of works on paper. It's done just protect the fragile papers. If you are going to show photos without glazing why do you need a traditional frame at all? I've seen a lot of photos, especially really really big ones, laminated onto Cintra or aluminum or even museum board that has then laminated to a stiff backing like Cintra or aluminum. If you don't want to laminate the prints you can just hinge them to a backing like museum board that can then be laminated to a structural backing which can then be easily hung on a wall.

If you are displaying photos in public areas though, it's best to seal them up in proper frames with good glazing but in the end it's better to have them hanging up than not hanging up.

[naturephoto1]

Would you buy a Porsche and put a VW beetle engine in it?

Robert,

Well there was the Porsche 914/4 based on 80 hp fuel-injected 1.7 L flat-4 engine based on the Volkswagen air cooled engine. :eek: :D

Rich

[roteague]

Robert,

Well there was the Porsche 914/4 based on 80 hp fuel-injected 1.7 L flat-4 engine based on the Volkswagen air cooled engine. :eek: :D

Rich

Ferdinand Porsche did design the boxer engine, which VW also uses (and Subaru as well). Of course, now that Porsche may be buying VW.... :eek: and Chrysler is building a minivan for VW :eek: perhaps, this isn't a good analogy any longer.

[Bruce Watson]

Ferdinand Porsche did design the boxer engine, which VW also uses (and Subaru as well). Of course, now that Porsche may be buying VW.... :eek: and Chrysler is building a minivan for VW :eek: perhaps, this isn't a good analogy any longer.

I hate to burst the Porche bubble, but the boxer engine design (http://en.wikipedia.org/wiki/Flat_engine) was patented by Karl Benz in 1896.

[alec4444]

The Acid Free Boards will not only last longer but the beveled cuts (acid board beveled cuts will yellow) should stay white for hundreds of years.

Hey Rich! No, I wasn't talking about the mount boards, but rather the photographic paper. Why use expensive papers like Bergger if you put the print behind glass? Could you tell the difference between Bergger paper vs Kentmere behind glass?


Would you buy a Porsche and put a VW beetle engine in it?

Not a great analogy, really. An engine has to do with performance and is the driving force (forgive the pun) behind the use of the car. The paper is not the heart of the photo, the image is. The paper is just the transport mechanism, more like the tires of the car.

I'm talking about visual aesthetics.....unless you're suggesting that aesthetics aside, the more expensive paper makes you feel like you're looking at a "better" print????

--A

[roteague]

I'm talking about visual aesthetics.....unless you're suggesting that aesthetics aside, the more expensive paper makes you feel like you're looking at a "better" print????

--A

I'm suggesting you get what you pay for, and you don't put an expensive frame around cheap paper.

[erie patsellis]

Would you buy a Porsche and put a VW beetle engine in it?

perhaps better phrased as "why did the 912 become a commmercial failure?" perhaps?


erie

[naturephoto1]

Hi Alec,

Sorry, thought you were talking about the mat boards. If the glazing material is high enough quality (such as Museum Glass or AR Glass) I would suspect that you would see the better quality of the paper and certainly the quality of the print whether B&W or color. I know from my own color Fuji Crystal Archive photos printed by a Chromir Machine and originally shot on transparency film with 35mm Leicas up to my 4 X 5 Linhof, you can most definitely see the quality of the printing as well as the quality of the paper.

Rich

[Oren Grad]

Why use expensive papers like Bergger if you put the print behind glass? Could you tell the difference between Bergger paper vs Kentmere behind glass?

Alec, more expensive paper isn't necessarily "higher quality" paper. The best paper is the one that offers the most harmonious balance of (1) characteristic curve, (2) color, (3) Dmax and (4) paper surface for the specific negative you want to print. In my experience there is little correlation between price and what I ultimately decide is the best paper for a given purpose.

Different people have varying preferences as to the relative importance of these factors. I want a glossy surface, though I don't care about subtle variations in the character of the gloss, and with that as a given, the characteristic curve is extremely important. Within broad limits, I don't care so much about Dmax, and within very broad limits, I don't care about color. YMMV.

Many of the differences that exist in these factors will hold up behind glass, while some won't. It's up to you to figure out whether the characteristics that would get obscured are ones that you care about. Framing (;)) it as "why spend more if you can't see the difference" obscures the questions you need to ask to figure out whether glass is a problem for you.

[alec4444]

Alec, more expensive paper isn't necessarily "higher quality" paper. The best paper is the one that offers the most harmonious balance of (1) characteristic curve, (2) color, (3) Dmax and (4) paper surface for the specific negative you want to print. In my experience there is little correlation between price and what I ultimately decide is the best paper for a given purpose.

Different people have varying preferences as to the relative importance of these factors. I want a glossy surface, though I don't care about subtle variations in the character of the gloss, and with that as a given, the characteristic curve is extremely important. Within broad limits, I don't care so much about Dmax, and within very broad limits, I don't care about color. YMMV.


I'm not sure how to describe it, but I think I find particular satisfaction in the "character of the gloss" ... I guess that's how I would describe it. Never really thought about that.


Framing (;)) it as "why spend more if you can't see the difference" obscures the questions you need to ask to figure out whether glass is a problem for you.

Damn it Oren, that doesn't fit my formulaic approach to the problem!! :D

--A

[Oren Grad]

Damn it Oren, that doesn't fit my formulaic approach to the problem!! :D --A

I think, in the end, that's going to be my epitaph: "it depends".

...insufferably pedantic Oren ;)

[Doug Keyes]

The experience is so much better without the glass in the way. Other framed art is presented without glass. So why do we? Sans Verre anyone?

To get back to the original question. It doesn't always look better without glass (plex).
Glossy papers are basically the same behind glass. You've got reflections either way. While fine art papers are much nicer without glass. Ultimately, as many have stated, it depends on how long you want to keep your print in good enough shape to view. It's not a matter of IF it will get damaged without glass, it's when. I prefer to print once and present my images. Not print again and again to replace damaged images. The glass is worth the sacrifice in perceived image quality to me.

I've done it both ways for both museum shows and gallery shows. I have images (without glass) get damaged to some degree, 100% of the time. I've had images (in glass) get damaged 10% of the time. Frames of course get dinged as well.
Basically, I can't afford to present my work without glass.

[Brian C. Miller]

I can attest to how glazing protects the image. A week after I hung a 4ft panorama, I found a long scratch across the length of the surface. Without the glazing, the image would have been damaged.

[Bob Gentile]

"... The experience is so much better without the glass in the way. Other framed art is presented without glass. So why do we...?"

Interesting thread. When I was in art school (many decades ago) we were told that art on paper was protected by glass while art on canvas was protected by varnish. Thus, water colors, silk screens, lithos, photos, pastels, charcoals, pen-and-inks, etc. were matted (so the glass wouldn't touch the artwork). Oil paintings, acrylics, etc. done on canvas were generally framed but not matted.

Unfortunately, like much of what I learned in school, I have no idea how true this is today. This idea may have had merit at one time and today we do it out of a sense of tradition. Or my art teacher may have been smoking dope that day.

[bruce terry]

For framed plat/pall prints, after comparing everything including the awful non-reflective plexi stuff, I found "Tru Vue Ultra Clear" glass the next best thing to bare-naked over matte surfaces. There's the usual glassy reflection factor but no loss of image punch as there is no green to neuter contrast and clarity. Ultra Clear is also somewhat better over glossy silver but UV protection goes out the window ... if that's a biggie.