This is topic PRO-35 SHUTTERS in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Rick Long (Member # 213) on 08-23-1999, 12:58 AM:
Please settle an argument for me. A projectionist I was working with on a service call, claimed that painting the aluminum shutter on a Ballantyne Pro-35 flat black results in a better screen image. I immediately ridiculed the idea, pointing out that the Pro-35 has probably the thickest shutter in the industry and certainly had the ability to block light during the pull-down phase.
During our Monday morning coffe break, I brought this up with two other technicians (as a point of humour). They jumped on the idea, saying that this probably would result in a better screen image, reducing "bounce-back" of light from the rear of the projector cover ect.
Neither of them would listen to the logic of my argument that light (travelling at 186,000 miles per second) would not, in the least be affected by any "bounce-back".
Has anyone tried this - and does it work?
Posted by Brad Miller (Member # 2) on 08-23-1999, 01:06 AM:
I'd have to say any improvement would be very minor.That's why I am so fond of the old GCC black shadowbox design. (Check out the GCC Northpark 1&2 pics in the warehouse.) Reflected light around the screen can kill the image in color saturation, contrast, brightness and sharpness. Thank you AMC for bringing us the damn curved screens! Curved screens (specifically Torus screens) suck! (...and I mean that literally) 
Posted by Gordon McLeod (Member # 33) on 08-23-1999, 09:24 AM:
It is interesting that all other projectors have black shutters and usually non reflective heat baffels in the shutter box
The pro35 does have an exceptional picture anyway
Posted by Mark Gulbrandsen (Member # 72) on 08-23-1999, 06:09 PM:
Don't paint any shutter in a Christie P35. Its supposed to be reflective of heat hence the silver anodize. If you do paint one black expect premature failure of the belt or gearbox. If you have any flickering check the shutter. If its the double wing type chenge it out to the newer single blade double speed shutter. The results are remarkable.
Posted by Jason Burroughs (Member # 68) on 08-23-1999, 08:12 PM:
I've noticed that Century as well as Simplex projectors come painted with flat black enamel.But speaking of Christie projectors, before I arrived at this theatre someone had let the lamp run while the projector was not running (and apparently the douser was open as well) and had melted the trailing edge of the shutter, the Ultramittant had drippings of aluminum from the melted shutter. Fortunatly since this damage was on the very trailing edge, the projector could still run, but had some travel ghosting as expected. We had ordered a replacement shutter, 1 month went by still no shutter, When a technican came out to fix an unrelated problem we asked him to order one for us as well through their supplier so we were waiting on 2 shutters now, finally hear back that the shutters are on back order from Christie, so we started urging the guys at Christie to finish their beers so they could turn the cans into our shutters. The other day 1 shutter FINALLY arrived, I quickly replaced the damaged on. When talking to the manager, I could belive the cost of this simple piece of aluminum. $375!!!! that's ONE expensive beer can let me tell ya. God where is a Century when you need one.
By the way, changing a shutter on a Christie is a pain in the butt.
Jason Burroughs is a projectionist at Loews Keystone Park in Dallas, TX
Posted by RICK HAMILTON (Member # 115) on 08-23-1999, 11:11 PM:
What is so hard about changing a CHRISTIE shutter? Try removing a PRO-35 shutter!
Posted by Rick Long (Member # 213) on 08-23-1999, 11:34 PM:
This is my point. The theatres I am considering trying this in start their performances at noon. This gives me a maximum of four hours to do service. Since removing a PRO-35 shutter involves unwiring the 3017A change-over control and framing light, removing the dozen or so screws that secure the back panel, removing the back panel, and then the shutter, I would have a difficult time justifying the time spent doing this unless there was a noticable improvement in the screen image.
Posted by Mark Gulbrandsen (Member # 72) on 08-25-1999, 11:04 AM:
You forgot the most important part of removing the Pro(?)35 shutter.........draining the oil. This machine is so overbuilt in so many ways, but then there's that darn piece of delrin in the dang thingy there???@#%$&!$$$$$$$$$$$$$$$$$$$$$$$
Posted by Rick Long (Member # 213) on 08-25-1999, 07:47 PM:
Sure, if you want to do it the easy way.
Posted by Rick Long (Member # 213) on 08-25-1999, 07:53 PM:
Actually, you don't have to drain the oil before removing the shutter, but you do have to take off the framing handle and the rear operating side cover. Couldn't agree with you more about that damn shaft coupler.
Posted by Gordon McLeod (Member # 33) on 08-26-1999, 01:54 PM:
Dumb question but why does the pro35 go through so many couplers yet the DP75 and the FP20 use the same device and don't go through them
They are interchangeable in an emergancy though they do leak then
Posted by Tim Reed (Member # 137) on 09-08-1999, 09:31 AM:
When Ballantyne copied them, they didn't do a good job.Ballantyne's can be modified so they don't eat up bobbins.
Posted by David Johnson (Member # 173) on 12-02-1999, 03:54 AM:
I have read the item on the Pro 35 and DP75/ FP30 couplings, I have never seen a Pro 35 and as far as I know they are not in this country. If I read it correctly you indicate that the kinoton couplings (framing bushes) are interchangable with the Pro35, I find this hard to accept as the DP75 is not interchanable with the FP20/30. The DP75 is longer and has fewer larger splines, while the FP20/30 is shorter and has more smaller splines, (I can give you exact number if you want). The Kinoton Framing bushes will fail prematurely if the gate tension is exessive and the end bearing is incorrectly adjusted, possibly this may explain the short life on the Pro 35?
David