Unfortunately, now that I have come across another laser pointer, and believe I have a good power supply, I am moving in less than 2 weeks, and will be forced to abandon my efforts in this. Has anyone on here made any such attempts?

1 enough brightness to achieve dolby level
2 Even slit illumination

One minor point:

These machines (Holmes) are 50+ years old. There are alot of them around, according to my E-mails, so, why is everything out the roof price wise?
The way things are going, I will never find magazines for my second machine.

I am getting tired of 20 minute shows, then an intermission while I rethread....

Is anybody here living in an under $100,000 house like me? I bought mine in 1986 for $16,000. It is appraised for 89,000 now. It has 1000 square feet of space, fully A/C'd, rewired, replumbed, roof, etc. One room is dedicated to the film collection. The rest of the house is not.

The point I am trying to make is this. I is poor! I am selling off a bunch of 16mm school projectors as quickly as I get them checked and lubricated, but it doesent go far with 35mm. I have one hi-dollar 35mm feature, and the rest are average stuff. I got lucky with accessories. $50 splicer, $90 electric rewind (in 16mm-paid $60 for the 35mm shaft)
My job is slowing for the winter, so money will be tight. Anybody (or all) in this mess? Oh yeah, I aint married, so no 2nd income to help out.

I love this hobby, but prices are insane. This is why I use Sony junk! When I got it, I worked for SEARS and got a good discount!

I have seen a solution with a standard 3mW laser diode at Technicolor labs, they had a standard 1950's type Phillips Cinema soundhead, where they focused the beam onto the slit lens, and claimed it works quite oK. Maybe you'll have success with your laser pointers.
Most reasonable laser diodes with slit lenses have anything but even light distribution. The converters which give even distribution are available from special companies supplying the medical and telecom field, and I have had a list featuring prices in XS of $ 1k per lens. We have been quite satisfactory with a standard line generator laser (8 degrees line) from Vector Technologies, which had illumination uniformity of approx 1.5 - 2 dB.
Disadvantage: about US 600+ without barrel or mounting. Laser claas 3A, which normally means, that you have to built a lighttight enclosure around your projector, which shuts off the laser, the moment you attempt to open the enclosure. So this solution may not be legal... but works. Compared to tungsten bulbs the noise floor is about 12 dB higher, but otherwise, using monochromatic light, you pick up less scratches from the film.

My brother, working in mediucal laser engineering at our medical university, told me about a possible $ 50 solution, but so far never came over with his knowledge. As soon as I know, I would tell about it.

I have a fair amount of experience with lasers, as I have been building them and working with them as a hobby for years. the only *good* one I have right now is a 10mW He-Ne, which I wouldn't part with even *if* I could fit the laser head in the soundhead.

so, my point is, a Jaxlight is out of the question.

And yes Bruce, there are even some theaters that are on a tighter budget than you are.
The theater itself is probably only worth no more than $150k especially considering that most of it isn't up to code (no fire sprinklers, emergency lighting, etc.) and it is in such shape because the "landlord" will not do any of the repairs, upkeeps, etc. necessary, and also IN THE CONTRACT. It would be so nice if someone could buy it outright from them and properly maintain and manage it. *hint* *hint*
so anyways, the current managment is probably going to dump the operation on some poor unknowing soul as soon as I leave (I'm the reason we still have equipment running) and then the whole thing is going to go under. Meanwhile, I need to find a job that pays well where I am moving to. If anyone out there is in west Salt Lake City area (Magna especially) please let me know, especially if you can get me a good job projecting or doing tech work. *sigh*

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Its too bad that the job slows this time of year. BUT, It IS nice to work a little less during the Holidays....

Since this is just a low budget home tinkering project, I'm thinking of making the LED more opaque by doing something to make the plastic appear cloudy. Of course this will scatter the light and make less light available.

Oh well. Merry Christmas and a happy 2000

This is may help you to understand why your well meant experiment wasn't successful.

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Are there really enough of the Holmes and DeVry projectors out there to warrant the costs of designing a laser system for these machines? Are many Holmes still in service in theaters? DeVry's?

Is their running speed as smooth as "real projectors?" Or am I just concerned for nothing?

As for the Holmes, I had a pair of these rascals many years ago and I did modify one of them to take a good "solar cell" by milling out a little pocket in the casting on the right side of the trap. Then I made a little bridge piece onto which I had cemented a mono raw cell (with RTV). However, I never worried about the exciter. Why couldn't someone remove the old socket and cobble together a mount from somewhere else that would accept a Jaxlite?

I know even less about the deVry, but I did once try to make a holder for a stereo cell but had to abandon the project because the slit lens was one intended for a 16mm projector and therefore would never have scanned the full 35mm track. Were they all that way? I don't know.

It's a tough problem, I know, and we have all recognized the need for an inexpensive solution, but it doesn't seem to be in the cards. From my conversations with Jack Cashin of USL, I have some idea of how much his Jaxlite has cost him not only in dollars, but in frustration as well. How about an LED manufacturer who agrees to make your design and then can't be bothered with a mere quarter million dollar order?

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