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Hacking a Carousel slide projector?

jay moussy

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I see free Carousel projectors all the time at my local dump, re-use/ recycle shack.

I have my own two precious Carousels, but just wonder what hack I could attempt with a free, expandable one?
Winter is coming, gotta find some dubious project..!
 
One that comes to mind is to combine it with a Raspberry Pi and a macro lens to make an automated slide scanner.
 
And it's always good to have spare parts.

Yes, and certainly when looking at the transport mechanism, a lot of stamped metal.
Also bulb, lens.

I always been curious about these projector lenses, their potential, if any.
 
As for spare parts, unfortunately the parts that failed on my 750H were plastic gears, and all those plastic parts are now about the same age, so...

When I replaced these gears the first time, in 2010, I believe the parts might have been new old stock from Kodak. (focus pinion gear, motor worm gear, and spur gear)

Nine years later the focus pinion gear broke again. This time I discovered the part was available from a third party that has taken the initiative to have the gears injection molded using modern plastics that should last longer than the original Kodak parts. Fingers crossed.
 
I always been curious about these projector lenses, their potential, if any.

Apparently LOTS of people use them -- not me -- as regular camera lenses. Because they usually are around 100mm, fairly wide aperture, they are popular for portraits. Lots of people add various camera mounts and sell them on EBAY. Check them out -- lots of great example results.
 

I have a 300mm f/2.8 projection lens.
 
I see free Carousel projectors all the time at my local dump, re-use/ recycle shack.

You are lucky. I came across three offered locally. Ever. And one of them I acquired. Hacking a Carousel sends me shivers down the spine.

But yes, I dismantled for parts some of the projectors common over here.
 
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They are really cheap on EBAY all the time -- except for shipping of course.
 
As for hacking I want to replace the lamp with one of lower wattage and has color temp of around 5000K for digitizing slides. The problem is that the lamp in the projector is 82V and I can't find the lamp with right wattage at 82V. Sure I can build power supply but I want to fit it inside the projector. Also I would want more diffusing material to make the light more diffused and even. After that I would work on the remote advancing.
 
Which lamp of lower wattage has 5000K? The only such lamps I know of were home-lighting ones with a blue filter coating.
 
I don't know why the 5000K colour temperature would be critical with a halogen (CRI = 100) source.
 
Yes, that is another point. Basically a slide is even intended for 3200K.
 
Which lamp of lower wattage has 5000K? The only such lamps I know of were home-lighting ones with a blue filter coating.

I forget the company name but yes they do have blue filter. Good CRI quart bulb in MR-16. Slide is intended for 3200K lamp but with 5000K lamp I get better color rendition when copying using a digital camera. Although the color temp of the camera can be set at a lot of different value I feel the native color balance is about 5000K.
 
An LED conversion would be nice. It would be easier on the slides due to heat reduction. No more bulbs to burn out, either.
 
An LED conversion would be nice. It would be easier on the slides due to heat reduction. No more bulbs to burn out, either.

Except that even the best, high CRI LEDs don't really provide the same continuous spectrum type of light as an incandescent/halogen/electronic flash source.
 
Interesting. that is the part of the projector I had in mind!
Could you tell us more details, what worls, what does not, and why?

The 300mm lens isn't that useful because it project very small image for the distance you have in a typical room. It's very heavy and it has to rest on the table. I don't want it to hang on the projector alone. I found my 50mm lens is more useful for large projection in tight space.
 
Except that even the best, high CRI LEDs don't really provide the same continuous spectrum type of light as an incandescent/halogen/electronic flash source.

Yes that's why I prefer not to use LED. Even though there is no MR-16 LED that is 82V. So yes I can have a 12V or so power supply no problem but I would like the power supply to be inside the projector and derives power from the same AC cord. Besides with about 300W of power with the standard lamp any diffusion material I addd to it would melt.
 
Except that even the best, high CRI LEDs don't really provide the same continuous spectrum type of light as an incandescent/halogen/electronic flash source.

And the original bulb is still available with some research on the web.
 
Except that even the best, high CRI LEDs don't really provide the same continuous spectrum type of light as an incandescent/halogen/electronic flash source.

But is that a problem in non-critical applications, such as a slide show? If the bare light looks white to people shouldn't that be good enough? You or I might see the difference, but without a reference point, will the color look off to the casual viewer? Lots of photographers use light boxes with 5000K fluorescents to view transparencies, and those have an imperfect spectrum.
 

As I understand it, the sought after light source is to be used in a project intended for volume digitization of slides.
 
And the original bulb is still available with some research on the web.

Definitely. I can even get them fairly locally. But my concern is that even with heat-absorbing glass, there is considerable heat that can't be doing them any good. It makes the slides pop in short order, necessitating refocusing.
 
As I understand it, the sought after light source is to be used in a project intended for volume digitization of slides.

Ok, I missed that. I thought he was just looking for an interesting project.
 

Such lenses were intended for lecturing rooms/halls.