Inspecting and Evaluating a Vintage Oil Painting (and More!) with a UV Blacklight: Good Condition? Restorations? Value and Appraisal? 3 Good Tips for Art Collectors
Every art collector questions the condition before a purchase… or should! Appraisers also rely on evaluations and inspections by art conservation professionals… and here’s your first tip:
When evaluating the condition of a painting, use the services of an art conservator that adheres to a professional code of ethics. I’ve worked with dealers and restorers in the US, England, France and Italy and this type of situation, where evaluating for sale and appraisal, is exactly the situation where a “head fake” is used to take advantage of the owner. The professional code of ethics of professional conservation does not allow for an art conservator to buy, sell or appraise (unless he’s a certified).
This landscape painting by Corot is a perfect example of the right questions to be asked and the conditions that we looked at.
Second tip: Ask this question… The appraiser wondered, first of all, did previous restoration/conservation treatments affect the condition? In this case, the cracking had been treated and the cracks were down/flat but still visible. It seemed to me that the visibility of the cracks, while not unstable, would be an aesthetic detraction. Even though this is not a condition problem, would it affect the value or desirability? In this case, a small amount of varnish and treatment along the cracks would make them much less visible.
Tip Number Three involves another condition question that should always be asked regards previous retouching (if its sloppily done) or inpainting (if its accurately done and held to a minimum). These are details that are most easily seen with the use of a blacklight. More on this important diagnostic method that you can/should perform at the end of the article. In the case of this 19th century Barbizon painting, the green glow of the varnish is so bright that you cannot see any retouching under the varnish. You would only be able to see retouching over the varnish. So, beware. How much inpainting affects the value? That’s not an easy question to answer and is better answered by an appraiser. Rule of thumb is that very little inpainting along a border and in non-focus areas of the composition can be insignificant. Even small fingernail sized spots and small rips, if located in non-focal parts of the painting can impact the value very little.My opinion about this painting was that it is in excellent condition and the appraiser was prepared to give its highest retail replacement value for insurance purposes.
So, let’s talk quickly about the use of a blacklight
My New UV Blacklight
I found a really great new inspection tool for collectors that you are going to love. I don’t know if the item is newly invented, but I’m newly acquainted with it. It’s a superpowerful UV flashlight that can be very useful for:
- • for looking at restorations on paintings
- • seeing mold spots and differentiating between different types of mold
- • reading inscriptions (written on stretcher bars or labels for example)
- • being the hit of the party at your kids/grandkids Halloween party
Perhaps you’d appreciate my evaluation of the quality of some of the UV lights available for purchase? Here’s a quick summary:
- • Hand held battery units:
- • Black light tubes (blast back to the 60’s)
- • The standard UV light you find being used is not so great
- • My favorite hand held UV inspection light
- • The super powerful flashlight version
UV (blacklight) inspection makes retouchings show up as purple blotches
(This is a very over-simplified statement)
Of course, UV inspection has been a normal technique for seeing retouching for decades. If you’d like a little technical info on the subject, here it is:
An art collector, when inspecting art, should use a long wave ultraviolet lamp in the 365 nanometer range. Be aware that all materials react to UV light in one way or another. When you learn the characteristics of what old paint vs. new paint does (plus other painting materials), you will have learned a diagnostic method that may save you $100,000, if not a lot more. BUT, also be aware that all UV lights (365 nanometer range) are NOT the same. The more intense or powerful the light, the better it does its job for you. Besides the power of the light bulbs, filters can be used to enhance the performance.
The characteristics of art materials can be seen as different colors, different types of “glowing”… or not glowing, bright colors or dark. But in every case, the viewing of paintings will always give you valuable information. This makes an ultraviolet lamp an especially useful instrument in checking the condition of all forms of artwork.
The ins and outs and variables of looking at artwork are best done in an “apprentice” sort of way. Looking at a painting with someone who knows what they are doing will allow you to ask questions and understand better. Utilizing a blacklight is not an easy, idiot proof diagnostics method for the general public. Although it’s easy enough to by a blacklight, you will make expensive mistakes if you don’t get some instruction. So, my suggestion is that you find a type of mentor or teacher to look at a dozen or more paintings with.
A darkened room is the optimum place to view an object/artwork with a blacklight, as you probably know. But sometimes that’s not practical. This brings up the subject of quality of UV blacklights.
Some blacklights are so weak that they are useless. I can’t tell you how many times collectors (and dealers!) have said they have looked at something with a blacklight and thought that no retouchings were present. Then, when looking at the artwork with a better light, the retouchings showed up like a Christmas tree! The hand held battery powered blacklights are a good example of this type of useless equipment. About $40.00 (various suppliers)
The next type of light we should talk about is the flashlight type: you should know that there are several kinds in varying strengths of UV light power. Most are useless. The most powerful can show up a lot of good details even when used in public settings without turning off the lights. These most powerful handheld flashlight type blacklights are 10 times stronger that other flashlight types that look exactly the same. So, know what you are buying. Prices range $25.00 – $125.00 (various suppliers)
The next UV light model you have seen used is a plastic housing model with an electrical cord. I have one of these and they are only “OK quality” but I can bang it around on the road. Only use this in a dark/blacked out room and let your eyes adjust before you start examining or you will not be getting good enough info to make a good decision. I only use mine if I have no other options. About $175.00 (Various suppliers)
The model I prefer to use, but don’t care it around with me on the road, is also a plug in. It is many times more powerful than the above model and gives me LOTS of additional info. It’s by far my favorite UV light. But it costs $395.00 (s/h included) instead of $175.00 Call me if you are interested and I’ll throw in 30 minutes of personal training over the phone. (805 564 3438).
By way of summary, what follows are a few things to think about. However, this is in no way comprehensive nor are you able to learn the specifics by reading, only.
Using Ultraviolet Light to Identify Repairs and Alterations
in Various Forms of Artwork
View artwork under ultraviolet light to see if any previous retouching restoration has been done. Dark purple blotches usually indicate retouchings, repairs, floating signatures. Different kinds and ages of varnish “glow” differently with different colors.
Porcelain, Ceramics & Glass:
Repairs and cracks in fine porcelain and ceramic art objects fluoresce bright white. Lead glass, with even as little as 1% lead, fluoresces an ice-blue color while flint glass appears white. Uranium-colored glass fluoresces a very bright green or yellow. Clear glass repairs are easily seen with the naked eye but not so in colored glass. Beware of judging the age of glass by the color, because short-wave radiation turns some clear glass to amber or purple in a matter of weeks rather than many years if aged naturally by sunlight. These techniques are particularly important with Asian art.
Bright areas in paper art show new patches of paper, residual gesso and bleached areas. Repairs have a variety of ways/colors of showing up. Mildew (foxing) appears yellowish and makes water stains easy to recognize.
New threads will fluoresce differently than old threads (dyes and colors).
Marble, Jade, Ivory & Clocks:
To determine the repairs of marble, jade, ivory and clock faces, an ultraviolet lamp is useful. Fresh cut marble will appear as a strong purple, while old marble will be a mottled white. Fresh carved jade will appear as an intense color and old jade will be mottled in color. Newly carved ivory will appear purple, but old ivory will be a yellow tone.
Here is a great offer
This is a package deal to meet major needs
of any art collector…
High Powered UV Blacklight Flashlight-
UV Black light DVD Instructional Video
Here’s an excerpt from the Video
We have only 100 packages available
• Consider the money you will save by NOT making poor choices/purchases.
• Consider how your increased knowledge will sound as you have art discussions
Our intention is to OVERPERFORM for you on this purchase and provide the highest quality supplies and instruction. It is extremely important to us that you get the personalized attention you need to make this purchase effective for you. Your satisfaction is guaranteed.
The flashlight is surprisingly effective even with the lights on… a great tool at an auction or while traveling (antiquing).