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lisasb
04-10-2008, 11:32 AM
Hi, gang -

I was wondering if any of you out there have any long-term experience with really cheap OPs like Pentels.

I have a set of Pentels I found in my garage (I think I bought 'em for my son), and I really like them for underpainting under my Holbeins. And hey, you can't beat the price -- $4 for 36 at DickBlick.

My question is, how permanent are the Pentel colors? Would they hold up for many years if they were fixed/varnished or framed under glass? My dry pastel works sold pretty well at my open studio last year, I would like to try to sell some of my OP works at open studios this October (assuming I get juried in again), but I don't want to sell stuff that's gonna fade or degrade over time.

I'm trying to decide whether to buy a higher-quality hard OP (Erengi or Specialist?) or just keep using the Pentels.

BTW, I've been experimenting with the fixing/varnishing technique I read about here at WetCanvas, so far it seems to work well. I'll keep you posted on my results when I've tried a bunch.

Thanks,
Lisa.

ZanBarrage
04-10-2008, 12:56 PM
Avoid the student grade oil pastels except for personal sketching. I have some experience with these. I just came back to Oil Pastels after a long absence (1995) when I looked at my pastels and at the works that I had done before with them, a clear difference came out:

Works done in Artist Quality sticks remained vibrant and vivid in colour. Those done with Student quality sticks had a white film on them as if someone had gone over them with a thin white glaze.

The oil pastel sticks did not fare any better. The student quality sticks also had a film on them almost obscuring the true colour of the stick. I had to rub them hard to get to the colour again.

Nop! Better off using the good stuff.

AnnieA
04-10-2008, 01:48 PM
Lisa: The issue of the lightfastness of student grade OPs is a question that comes up a lot and I don't know if there's really a definitive answer. I have some early works done with some Pentels and Gallery OPs about 10 years ago, and there doesn't appear to be any fading. One thing to consider: some of the OP fixative/varnish products on the market say that they block UV rays (those are what's responsible for the fading), so that might be an option to prevent fading of already-completed works. It's Sennelier specifically that I know says it's a UV protectant, but the Sennelier fixative/varnish has the drawback of being highly glossy. I guess there's also a UV protecting picture glass, but I understand it's pretty expensive.

FWIW, I've heard about the white film that Zan describes, but haven't seen it on any of my older works.

For any new OP works that you plan to offer for sale, if it were me, I think I would err on the side of caution, and use only artist grade products. I'm not entirely certain what to say about your existing work. Sorry I couldn't be of more help.

sundiver
04-10-2008, 03:58 PM
Moving this thread to Pastel Talk, as it is more appropriate there.:)
In Pastel Talk, Zan, if you do a search (in"Search this Forum")on Pentel you may get some more info.

starblue
04-10-2008, 05:17 PM
Could the white film be "wax bloom"? When you burnish a work done with wax-based colored pencils, wax bloom often develops. Student-level OP's have a lot of wax in them. The solution for CP's is to buff the artwork with a soft cloth to remove it, then apply fixative, but from what I've read, you don't want to apply a regular fixative to OP's, and the Sennelier fixative makes things very glossy.

As an aside, I've noticed that Senns or Holbeins applied heavily and then rubbed with my hand develop a very waxy sheen. It's not true wax bloom but does demonstrate that even the artist's-level brands have quite a bit of wax in them.

ZanBarrage
04-10-2008, 06:22 PM
Hi Bob,

That could be a good idea except for the fact that you can't really buff oil pastels without smuding them. It could very well be wax bloom. You may be on the right track there. Thank you.

Scarefishcrow
04-10-2008, 10:32 PM
Avoid the student grade oil pastels except for personal sketching. I have some experience with these. I just came back to Oil Pastels after a long absence (1995) when I looked at my pastels and at the works that I had done before with them, a clear difference came out:

Works done in Artist Quality sticks remained vibrant and vivid in colour. Those done with Student quality sticks had a white film on them as if someone had gone over them with a thin white glaze.

The oil pastel sticks did not fare any better. The student quality sticks also had a film on them almost obscuring the true colour of the stick. I had to rub them hard to get to the colour again.

Nop! Better off using the good stuff.

Zan, what you describe reminds me of a phenomenon that I cam across and posted the following reference to in another thread. Pat and Wendell were not familiar with this.
The link is to a summary of a study that discusses fatty acid evaporation from oils used in art media and effects of environmental conditions on rates.

http://palimpsest.stanford.edu/waac/.../wn21-106.html

In addtion to the triglycerides in the oils of art media, there are also various amounts of free fatty acids that, as this article explains, evaporate over time and are known to cause a white deposit on the glass covering paintings. This may be the origin of the whitish film on your cheaper pastel sticks.

While certainly the only dependable way to ensure quality would be use of artist grade oil pastels, I'm not sure that any of us have really answered Lisa's real question (as I interpreted it). She wants to know if using student grade OP to accomplish an underpainting would be ok. I am assuming that the completed work she would be selling would be done solely with high quality, artist grade OP's OVER the student grade underpainting.

I seem to remember others referring to doing this as an option. I'm not really sure that the problems discussed have really answered whether an underpainting of student grade OP would be ok if covered and finished with artist grade OP.

Would that make any difference in your responses to Lisa's question?
Lisa, have I interpreted what you were asking correctly?

I'm not sure that as an underpainting this would be as critical an issue assuming a complete overpainting with artists OP. What do others think?

ZanBarrage
04-10-2008, 10:53 PM
You are right Bill we probably all focused on the student/artist issue and left the real question un answered. So let me state my view:

I consider under paintings as an integral part of the whole. Especially in pastels, the under painting sparkles through or should and gives vibrancy to the work. If this effect is to remain over time, I doubt that student grade pastels should be used. If the issue is cost, I would suggest Acrylic under painting. The paint spreads better and over all might be cheaper. Moreover one could use sand in acrylic and create a nice surface on which to deposit oil pastels.

In my humble opinion, there is no room for student grade art material in professional works. I still use student grade pastels for sketching. They are much safer to carry around than Senneliers, but these are just for me and will never be sold.

Speaking of all this, I just refreshed my supply of Sennelier on ebay. I bought a set of 24 basic colours for $25! You can't beat that! I brought them from the post office today and both my wife and my 8yr old daughter were drooling over them. My 4yr old had a sparkle in her eyes when she saw them. She, I worry about! Three of these have cadmium in them so they will never touch them, but I can't wait to move into our new house in June so that I can have my own atelier.

Scarefishcrow
04-10-2008, 11:11 PM
Zan,
I think that you are probably correct that the safest and most reliable route is to avoid student grade. With Erengi ArtAspirers and Craypas Specialists (both artist grade and available in full sets of approx. 90 colors for between 70-100 dollars, (smaller sets, less) there really is no fiscal reason not to invest in artist quality if you expect to sell the work. After all, think about it.....at $5 for 36 sticks, how much quality can you possibly expect??

Other options for underpainting include watercolor or guoache if you are working on heavy watercolor paper or board. Some people have suggested OP sometimes doesn't adhere as well to Acrylic, have you ever noticed that as a problem?

Congrats on the new house. I'm covertting my home office into a studio since I retired in January.

You'll have to tell us about your new atlier when you get settled in! Sounds like you have some budding OP artists in your family!!! They certainly have someone that can teach them well.

AnnieA
04-11-2008, 06:58 PM
I hate to always be the iconoclast, but have either you, Zan, or you, Bill, read Kenneth Leslie's excellent book, Oil Pastel: Materials and Techniques for Today's Artist? (http://www.amazon.com/Oil-Pastel-Materials-Techniques-Todays/dp/0823033104/ref=sr_1_9?ie=UTF8&s=books&qid=1207952699&sr=8-9)

It's in that book, I believe, that there was a very informative section on lightfastness. Leslie had completed his own year-long lightfastness tests. I seem to recall that there were several brands of student grade OPs (notably Cray-pas as I recall) that actually did better than most of the artist grade brands! Now, the book was written some time ago (sadly, it's out of print), and I think several of the artist brands have reformulated their lines since it was written (I know that Sennelier did), but it's still significant to note that some student brands did relatively well in the tests.

That's why I'm a little hesitant to speak out quite so strongly against student brands in favor of the artist brands. Since there is no outside entity that tests or confirms the manufacturer's claims about lightfastness, or even what pigments or other components the OPs are made of anyway, can we really know without doing our own tests? I do agree that for any new work it's probably wiser to use only artist grade materials, even for underpaintings, but I don't think the lightfastness issue for student OPs is really completely resolved at this point.

I wish I could remember what Leslie determined about the lightfastness of the Pentel brand, but I'm afraid I don't at all (it's been probably 10 years since I read the book). So Lisa, perhaps you could find a copy at your local library, and see for yourself what Leslie found out about Pentels. Another strategy might be to offer the works for sale, but put some sort of notice on each piece done with Pentels describing some of what we've been talking about here. Or maybe you could write to the Pentel company, just to see what sort of info they could send you on the lightfastness of their OPs, and if the info is positive, pass on whatever they've written to potential buyers as well (although as I noted above, manufacturer info may be suspect), explaining to them that OPs are a relatively new medium, with some remaining unknowns. Maybe you could offer a buy-back or replacement guarantee if any of the paintings in question does develop a problem.

Scarefishcrow
04-11-2008, 08:12 PM
Annie, you an iconoclast????:lol:

I wish I had Leslie's book. I agree that there is much unknown and OP's are begining to list CI Names and Lightfastness ratings of the pigments used and this should help one decide if the Pigment is safe to use for archival work.

I still plan to set up some tests of various brands, but haven;t gotten around to it yet. I guess I would be leery of any brand that does not supply CI names and Lightfastness ratings for their OPs. With that information you can make an educated decision, without it you are taking a shot in the dark.

starblue
04-12-2008, 12:36 AM
Just some more data points. I saw in a store the other day that Faber-Castell OP's explicitly and prominently say on their boxes "lightfast, archival, acid-free". At artmaterialsupplies.com they say Van Gogh OP's have these stats: out of a full set of 90 colors, 75 colors are rated for 150 years under museum lighting, 7 colors are rated for 75 years, and 10 are fugitive (rated for 5 years--I assume these are the flourescents)--lightfastness for each stick is given too; meanwhile, Blick's site say most of the Van Goghs are single-pigment formulations. Pentel at their site says their OP's are acid-free but there's nothing about lightfastness that I could find. None of these places listed pigment makeups.

ZanBarrage
04-12-2008, 09:16 AM
Annie you are right about testing. I did speak from my own experience and did refer to the graying out of my student grade pastels. As I said before, these were more than 10yr old sketches and sticks.

As to pigment and testing, Sennelier does give the exact pigments used in the formulation of the OPs and these pigments are what one can trace back to see their lightfastness. For instance the Sennelier Yellow Deep is PY35 which is Cadmium Yellow. Does anyone have a fresh holbein stick? Does it have an imprint of the pigment used?

Peiwend
04-12-2008, 11:52 AM
Zan, on the new packaging for Holbein Artist Oil Pastels that I have, there is no information on the pigment used. However, in the thread "Oil Pastel Color Charts" in post # 24, Annie gives a link to the Holbein website which gives pigment information for all Holbein products.

_____________________________Wendell

lisasb
04-12-2008, 12:36 PM
Thanks for all the information, everyone, it's a pretty interesting question. Bill, you did paraphrase my question correctly -- so far, I've only used the Pentels as a minor part of the underpainting under Holbeins and Senneliers. Basically I sketch the composition and block in some lights and darks with the Pentels, then switch to the artist-grade OPs.

The thing is, as you know, my expensive artist-grade OPs melt in the hot sun, so I'm looking for a harder (cheaper) alternative for plein air work. I have a couple of Specialists, but I just can't get comfortable with them.

The Pentel box says, "long-lasting, fade-resistant," which is not the same as permanent, lightfast, so it would probably be best if I just broke down and bought some artist-quality -- Jerry's is offering 50 ArtAspirers for $35 -- you can't afford not to buy! Bill, do you like your ArtAspirers?

Annie, I am going to get the Leslie book if I can, it sounds like it has a lot of useful info.

BTW, when I got my Holbein set I got the color/pigment chart, but I have to admit, it's very puzzling. For example, Burnt Sienna is rated as "Not durable" on the Munsell scale, yet is contains only pigments that are also in colors that are rated durable.

Burnt Sienna (not durable): Titanium oxide, Red iron oxide, Disazo yellow
Hansa Yellow (durable): Disazo yellow, Titanium oxide
Venetian Red (durable): Titanium oxide, Red iron oxide, Black iron oxide

I imagine some of you scientists out there can explain this, meanwhile I think I'll keep experimenting with Marilynn Brandenburg's techniques for fixing/varnishing...hopefully that'll give the pigments plenty of protection.

Lisa.

lisasb
04-12-2008, 03:12 PM
Zan, I'll bet you're excited about having your own atelier in your new house! I just recently converted a room in my house to a studio, and it's heaven. I gave my 10-year-old his own corner, with a work table and storage for some of his supplies, so he's really happy, too.

I let him try out some of my Holbeins/Senneliers a couple of days ago (yes, I'm crazy), and he was covered in OP after about 1/2 hour. (But very enthusiastic about the working characteristics of the holbeins vs. Pentels :heart: ). Don't worry, I cleaned him very carefully afterward. Murphy's Oil Soap works great.

Lisa.

AnnieA
04-12-2008, 04:20 PM
Bill: Yeah, I sure wish I had a copy of the Leslie book too. I liked it much better than the Eliot book. Unfortunately, it's out of print now and almost 50 bucks on Amazon last I checked. :eek: That's pretty steep for me.

Bob: Even the lightfastness ratings for Senneliers don't sound much different than those for the Van Goghs, then. Too bad they're so waxy, although perhaps in hot weather that isn't as noticable.

Zan: It looks like Wendell has answered your question about Holbein. I think Holbein offers the info in a downloadable pdf which includes info on all their product lines. The only thing that bothered me about the chart was that I think every OP was listed as including white (as you know, Holbein offers tints of each basic color), so it was difficult to know if any of their OPs was pure single pigment. I guess the addition of white isn't too objectionably, really, though.

Lisa: What is it that you don't like about the Specialists? Whatever it may be, I wonder if they might handle better in the hotter conditions of plein aire. Maybe you ought to try them on a really hot day to know for sure.

As far as the color/pigment charts, I've discovered a couple of errors in both the Sennelier (at least the one that's included with their "Retailer" brochure) and the Caran d'Ache charts, so it may only be an editing goof that you found. At any rate, best of luck with finding the right OP and/or varnishing method and thanks for an interesting thread. :)

Scarefishcrow
04-12-2008, 08:09 PM
I hope I can remember all the issues raised, but I want to comment on some. Just to keep from confusing things, I'm not going to try to attribute the comments.

While the Leslie book is out of print, there are two general, "encyclopedic?" reference books to artist materials in addition to the "Artist Handbooks" by Ray Smith and Simon Jennings. However, I have not seen the latest edition of one and not seen the other at all. The oldest was originally published in 1947, I have the 3rd edition from our library, but there is a newer 5th edition. The edition I have is "The Artist's Handbook of Materials and Techniques" by Ralph Mayer. 1970 Viking Press. He appears from his writting to be rather stodgy an certainly not inclined to less traditional media and methods. An iinteresting aside is that nowhere in the book are OP mentioned and "crayons" and the like are referred to as giving a "smeary" appearance apparently acceptable to a few newer generation artists... Newest edition available at Jerry's

http://www.jerrysartarama.com/art-supply/catalogs/0021940000000

What I would really like to get is
The painter's handbook (http://worldcat.org/oclc/27811806&referer=brief_results)
by Mark David Gottsegen
Language: English Type: http://worldcat.org/wcpa/images/icon-bks.gif Book
Publisher: New York : Watson-Guptill Publications, 1993.

Available at Cheap Joes:
http://www.cheapjoes.com/art-supplies/10379_the-painters-handbook-revised-and-expanded.asp

This is authored by one of the founders of The following web site/forum devoted to Art Materials Information Education Network (AMIEN) at this site: http://www.amien.org/

He also works with ASTM in producing standards for art materials manufacture.

Some other refs I found are:

Everything You Ever Wanted To Know About Art Materials (http://www.worldretailstore.com/item/BE-1581800827.html)
Sidaway, Ian
Spiral
Edition: Quarto Book
144 pages
Published: 2001
Publisher: F&W Publications Inc
ISBN / EAN: 1581800827
Price including delivery to: USA->US$32.20; U.K.->US$32.50
EU->US$32.50; Aus/NZ->A$47.10; Other countries->US$36.70




As for ArtAspirers, I personally like them very much. They are round, about the diameter of pentel or Neops. They have a working property similar to NeoPastels. However, they are slightly firmer, but definitely creamier than Specialists. I would personally recommend them highly with the caveat that everyone's taste in feel is slightly different.. IMHO I think they are an excellent value.

I am slowing trying to work on the color charts thread with a long term objective of having as much information about pigment content, color charts and hand colored charts for comparison, along with photo color charts of the sticks themselves. There are already quite a few links and examples.

Can be found here: http://wetcanvas.com/forums/showthread.php?t=483701

Have to go to dinner according to the wife. Later. Lot's of good questions and much to explore.

ZanBarrage
04-13-2008, 09:05 PM
Lisa,

I am very excited about having my space again. I will inundate you all with pictures once I have it done.

Please keep the cadmiums away from your son. The problem with artist quality paints and pastels is that they have dangerous pigments in them Cadmium is especially nasty for children. It can get into their systems through the skin. If he is feeling tired or thowing up, you may need to take him in. Not a joke.

lisasb
04-14-2008, 01:10 PM
Zan: Well, I have been careful the keep him away from the cadmiums, and I did wash him very thoroughly afterwards -- but you're right, probably as a general rule, I should keep him away from any pastels that are not rated ASTM non-toxic. I think I'll keep him on Pentels in the future, they use those at his school.

Bill: Thanks for the info, I've actually ordered a set of ArtAspirers, since they seemed to be the best value and probably have working characteristics I like.

Annie: Honestly, I haven't used the Specialists much, but they feel kind of big to me, I have a little trouble controlling them. I haven't ruled them out, I have a few colors I will try out on the next hot day.

We've had a spell of ridiculously warm weather for early April, so I made it outside to do some sketching several times. I would post my efforts, but I broke my camera (sigh...) -- I dropped in from a height of about 6 inches onto a table. Everything kind of popped off.

It was old and having problems, so I guess I'll shop for a new one, but the timing is lousy -- tax week!

Lisa.

lisasb
04-14-2008, 09:55 PM
Zan: Well, I have been careful the keep him away from the cadmiums, and I did wash him very thoroughly afterwards -- but you're right, probably as a general rule, I should keep him away from any pastels that are not rated ASTM non-toxic.

Oops, I mean AP non-toxic, I guess.

Lisa.

LaraSophia
04-24-2008, 03:39 PM
The best student grade affordable oil pastels I have used are Crayola.
They don't crumble apart and a pack of say 16 costs about 3 dollars and they are thick enough to handle easily for small hands.

-Lara
an art teacher

Pat Isaac
04-24-2008, 04:42 PM
I didn't know that Crayola made any oil pastels. I'll have to take a look at them. Thanks for the info, Lara.

Pat

Scarefishcrow
04-30-2008, 07:03 PM
I hate to always be the iconoclast, but have either you, Zan, or you, Bill, read Kenneth Leslie's excellent book, Oil Pastel: Materials and Techniques for Today's Artist? (http://www.amazon.com/Oil-Pastel-Materials-Techniques-Todays/dp/0823033104/ref=sr_1_9?ie=UTF8&s=books&qid=1207952699&sr=8-9)

It's in that book, I believe, that there was a very informative section on lightfastness. Leslie had completed his own year-long lightfastness tests. I seem to recall that there were several brands of student grade OPs (notably Cray-pas as I recall) that actually did better than most of the artist grade brands! Now, the book was written some time ago (sadly, it's out of print), and I think several of the artist brands have reformulated their lines since it was written (I know that Sennelier did), but it's still significant to note that some student brands did relatively well in the tests.

.

Annie..As you may have already seen in the Gusher posts, I happened upon a copy of Leslie's book in a used bookstore in (of all places) the Milwaukee airport (another story in itself). I purchased it for $15 and with all due respect to Elliott, it is head and shoulders above his book in diversity of content, usable information and tehcniques. I was astounded at how many artists he had figures from 15 years ago that were already doing incredible things with OP.

I hate to be an iconoclast to an iconoclast and my memory is usually not very good, so I hope you don't take this wrong because you always are are a wellspring of knowledge. However, Leslie's tests did not come out as you recalled. He tested Senn, Holb, NeoPastel, Panda, Grumbacher and Craypas. I have attached scans (both color and gray scale) of his figures but will summarize his findings:

Only 1 Senn showed minor fading. While a few Holbeins and NeoPastels showed fading, he generally found them to be good. To quote Leslie "...Grumbacher and Craypass were not found to be impressively lightfast...." I.E., both brands had considerable fading in significant nummbers of colors. The big loser was Panda in which virtually EVERY color tested faded.

Now, as you point out, in the intervening 15 years much reformulation has likely taken place. For example, Leslie indicated that the Senn formulation contained small amounts of siccative oil and that they recommended use withing 2 yrs of pusrchase or hardening might begin to occur. That seems unlikely to be the case today, but we really don't know the formulations accurately.

Armed with Leslie's model and results, I think it is time to retest all brands possible. I think more consistent and rapid results would be obtained using high intensity artificial lighting on a continuous basis rather than sticking the samples out on sunny days as Leslie did. I have in mind a scheme that would allow simultaneous testing of no light, direct light, and light through glass (which should absorb UV and reduce the light effect. Any suggestions or comments on testing design would be welcome.

I also picked up a couple of Michael Wilcox's books (Blue and Yellow don't make green" and the "Wilcox guide to all major brands of watercolor with all conceivable data, much obtained from the companies that cooperated well. I wonder if his School of Color might be interested in developing similar work on OP as they have expanded their series to include various other media?

Anyway, I wanted to clear up the confusion which I think others may have alluded to as well, Annie. Interestingly, he uses and discusses Oil Bar/Stick along with OP. In fact he first started using OP as underpainting medium for his oils (something indicated as probably bad practice by some). There is really so much we don't know and spend our time speculating on. We should form a group of interested parties to cooperate on comming up with various systematically designed tests and carry them out to answer some of these questions. It would be time consumming and often tedious to document correctly, but the information obtained would be invaluable and there is no telling what little mysteries we migtht uncover along the way. Anyone interested????

Images attached of Leslie's lightfastness test.
Bill

lisasb
05-01-2008, 06:18 PM
Bill, it sounds interesting to me. I've already started a very non-scientific test of the Pentels by sticking swatches in the window of my van. Some UV protection from the glass, but a lot of sunlight. I'd be willing to test out samples of all the OPS I have, we have plenty of sunshine in California (when it's not foggy), so I could do open-air testing or something.

The other thing that might be interesting is to test lightfastness with fixing/varnishing.

Let me know...
Lisa.

Pat Isaac
05-01-2008, 06:28 PM
I'm glad there is always someone else out there willing to do all this technical stuff. It is very interesting and I might want to pursue it, but presently I just don't have the time. Thank you all for your efforts. Much appreciated and maybe after I get through this show I'll have some time to do some.

Pat