This is topic Photoguard/Imageguard in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Mathew Molloy (Member # 666) on 02-07-2002, 10:59 PM:
I've read about not accepting prints that use Photoguard or Imageguard. Can you guys explain these processes to me and why the Tech. depots (or studios) do this? What are the benefits of these processes and of course, how is it detrimental to the presentation or is it only bad for the print itself? Thanks in advance for the insight!
Posted by Josh Jones (Member # 447) on 02-07-2002, 11:04 PM:
Photoguard is a epoxy like material that is put on the film in an attemp to protect it from scratching and also dirt. It is a nightmare with acetate prints because it will not allow the base material to breathe. accumulation of accetic acid rapidly accelerates the rate of vinigar syndrome, which is the decomposition of the base material. Also, if the process is not done properly, little snow flake patterns can be seen on the surface of the film. because of this coating, film guard cannot penetrate the base of the film and lubricate it. it can still help with shedding and static reduction.Josh
Posted by Brad Miller (Member # 2) on 02-07-2002, 11:34 PM:
It's primary purpose is to hide scratches. It can actually do this pretty well, but this comes at the cost of image registration. The labs are cranking out poor enough quality prints as it is right now and heaven forbid you should get a "flat" film printed at Deluxe Hollywood! Adding the PhotoGuard/ImageGuard coating only magnifies this problem. It also causes extreme shedding and the film itself is very tacky and runs very rough through the projector. As if that isn't bad enough, the coating acts as a dirt magnet and will manage to grab hold of every speck of dirt in your booth and adhere it to the print. Since the coating is inpenetrable, nothing you do in terms of lubrication or film cleaning will do much good.It's nice in theory and the initial viewing of a scratched print is impressive (provided you can ignore the new registration problems that accompany it), but in the long run it is a terrible thing to do to film, and your presentation will be paying for it a couple of weeks down the road.
So if come Oscar time TES decides to make some extra bucks by convincing the studio heads that they should hire them to put this crap on their prints, DEMAND a non-treated print. Even just a regular sub run print will generally look better a week into your run with a film cleaner than a "rejuvenated" print will after one week.
Posted by Ken Layton (Member # 133) on 02-07-2002, 11:44 PM:
I agree with Brad on this one. Photoguard multiplies the shedding problem ten-fold!
Posted by Frank Angel (Member # 248) on 02-08-2002, 12:46 AM:
3M insists that their Photoguard coating is NOT a sealant and it allows the base to "breath." The 3m people are quite adamate about that fact (naturally, because if it were not porus to gas, it would promote VS, trapping the acidic gas inside the base like whatever it was that Disney used to do with all their rerelease prints). And although I don't have the experience that you guys have had with it (I never had a full print that was Photogarded), I have had dozens of snipes from Filmack who treat all their stuff with it, and I must say, these snipes, some of which are over 20 years old, have held up much better than non-coated snipes and trailers. They are much more scratch resistant than non-coated and none of them show any signs of VS. And although they do have a different feel than non-treated film, I never found the coating to be sticky; and I've never seen any screen jitter either. In fact, all the Filmack trailers are almost always of static material, titling, still images, etc, the very kind of thing that you would expect see signs of registration problems. So my experience with it is different and hasn't been with whole prints. For snipes that you have to run thousands of time, give me Photoguarded film every time.
Posted by Mathew Molloy (Member # 666) on 02-08-2002, 12:58 AM:
How can I tell if a print has been treated?
Posted by Joe Redifer (Member # 3) on 02-08-2002, 01:19 AM:
If you have a treated print or some reels in your print have been treated, it will show up as a shiny tacky surface on the base side only. They do not treat the emulsion side. The treated side will look more reflective and will seem and just won't "feel" like film, so to speak. Perhaps someone has a better description? I wish I had taken pictures.Filmguard can run stuff thousands of times and the print will still look like new. I have seen prints over a year old that have been run 6 times a day for 6 months straight look like brand new. Not even a speck of dirt.
Posted by Brad Miller (Member # 2) on 02-08-2002, 02:31 AM:
Frank, a short snipe is one thing, an entire feature is another. Also, Filmack uses real 3M PhotoGuard. Technicolor uses that Dacar's ImageGuard knockoff and only treats the base side. (Now really, how STUPID is that?)
Posted by John Pytlak (Member # 331) on 02-08-2002, 06:45 AM:
Some links:
http://www.3m.com/market/consumer/photogard/overview.html
http://www.3m.com/market/consumer/photogard/film.html
http://cmtech.com/page29.html
http://www.eyecote.com/cmuv/cmuv3.htm
http://dacarproducts.com/igard-div.html ------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Research Labs, Building 69, Room 7525A
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion
Posted by Dave Macaulay (Member # 813) on 02-08-2002, 09:27 AM:
You can tell a photogarded print by the smell. It's hard to describe but unique - a chemical smell very different from the "green print" smell. A well used print doesn't smell as much but new ones reek.
Imax prints were (are?) often photogarded. There were lots of problems at first, but David Keighley Productions took over the machinery and refined it considerably for 15/70 use. The problems were mostly from coating the perforations, tiny flakes would get pulled off and they made an ugly mess, plus they stuck to the field flattener lens (and were in focus). Also if you hurry it the coating doesn't harden completely.
The goop is picked up on a bristly roller and transferred to the film, it gets a bit of time to smooth out and then gets developed in high intensity UV light. It isn't an epoxy, it's a UV-hardening material. I think it's silicon based. An Imax reel takes quite a while to process, it runs slower than projection speed - probably around 35 speed or ~100fpm.
I don't know who does the 35 coating. If they cover the perf area you will get snow around the intermittent.
It does work. Coating a new print protects the emulsion, and the main Imax problem, cinch marks, pretty much goes away. PTR rollers work well with it, the coated surface is very slick and dirt comes off easily. Don't try those sticky "silly putty" rollers - they bond to photogard.
It is rarely used on 35 prints, the cost is nuts for a throwaway print. (and they are all throwaway these days...) but snipes that get reused will look a lot better as time goe by.
Imax has some trouble with the prints coning on the platter with photogard, it's much more slippery than emulsion and the film slides against itself easily. Has anyone seen this with a coated 35 print on a platter?
Posted by Gordon McLeod (Member # 33) on 02-08-2002, 09:40 AM:
Photoguard usually has a rather punjent odour much like that around a brewery
I have never had a vinagar problem with it nad have had several Acetate prints in 70mm with it
As for registration I haven't noticed any problem with most machines such as ernamann or norelco/kinoton
The white powder is what chips out of the perf wall area and is a pain but usually goes away after a dozen or so shows
A lot of printing negatives get photoguarded to protect them during high speed printing
Posted by Frank Angel (Member # 248) on 02-13-2002, 01:36 AM:
Brad, Leave it to TES to try to cost-cut and screw up a good thing.