The first thing you need to do is figure out whether your camera and projector are compatible.

I did this first by re-lamping my projector with one of the energy efficient florescent bulbs.  This isn’t that critical for testing purposes.  Just find yourself a lamp socket and cord to power the bulb and insert the bulb where your projector lamp was.  They are bright and burn cool, so you shouldn’t have to worry about melting your slides.

 

The next step is to check you camera’s ability to focus and fill its frame.

I stacked a couple of books in front of the projector’s lens to sit my camera on and to maintain alignment. You’ll want to play around with this phase to determine what settings work best for your setup.  I found with mine that setting the projector’s lens to minimum focus distance and my camera’s optical zoom to 2.5x gave me the most reliable results.  It filled the camera’s frame and the camera’s ability to focus was consistent and reliable.  Hint… use the border of the slide to check focus, I wasted nearly an hour with an out of focus slide.  Also if your camera has macro focus or manual focus modes try them as well.

 

Once you’ve determined the settings for your setup and have recorded them, you can proceed to fixating your camera and projector in order to get consistent results.  Some of the recordings you’ll need later,  Approx elevation of camera, distance of extended camera lens (provided your lens extends and retracts) to the  projector’s lens,  the camera’s telephoto setting if it was used and the projector’s zoom setting if it has one.

 

 

 

 

 

 

 

 

 

For fixating the camera and projector I used a scrape piece of 12” x 16” x ¾” plywood.

I first centered the projector at one end of the plywood base. Then I trapped it with scrape strips of lumber that were screwed down to the 3/4” base at the projector’s perimeter, allowing zero movement.  Because my projector had a single height adjustment leg, I shimmed both sides of the projector’s base with a couple of wooden clothes pins to keep it from rocking or tipping.

 

Now things will slow a bit as you need to come up with an adjustable mount for the camera.  I opted for a 3 point leveling system.  You may come up with something different.  Whatever you decide, you’ll need a means to align the camera as if you were docking the shuttle to the space station.

 

I first cut a piece of ½” plywood down to 4”x 8”.  I next centered the piece in front of my projector, keeping in mind where the camera would be located and then drilled 3 holes in a triangular pattern all the way through the ½ and ¾ bases.  I tend to eyeball most things so forgive me for not having a template.

 

I had a scrape piece of 10/24 all thread rod that I cut 3,  3” lengths from.  (note, 3” is probably longer than necessary, I was winging it and thought they may come in handy later)  I fixed the 3 rods to the ¾ base using nuts on either side.  (In my case I actually used T nuts on the bottom of the ¾ base to eliminate any protruding hardware).

 

I next installed a wing nut and washer on each of the 3 rods and then installed the ½” leveling base, followed by more washers and wing nuts.

 

For the camera’s base I cut another piece of ½” plywood smaller than the first, 2.25” x 5”.   I located it near the projector keeping in mine the measurements I recorded in my testing.  I placed the camera on the board and marked the location of the camera’s threaded mount.  FYI, most cameras use a ¼ - 20 threaded mount.  I drilled a hole through the base plywood and on the bottom side countersunk a hole so the bolt’s head wouldn’t protrude.   NOTE: you need to be real careful when sizing your mounting bolt.  Most cameras only allow a few full turns of the screw into their mounts before the screw bottoms out, and if it’s to short you can strip the plastic threads.  I had to cut my bolt down and do some filing before it was the perfect length.  You can also shim the cameras off the base.  I did this with a strip of rubber cut from an old inner tube, plus it compensated for the irregularities in the camera’s base.

 

Once you have the camera mounted to its 2x5 base you can sit it down on the 3 point base and begin making the proper alignment adjustments in your setup.

I found the easiest method was to turn on the projector and set my camera to minimum zoom, which gave me an image looking down the barrel of a gun (projectors lens).  Once the rough adjustments were made then I would zoom in on the slide to full frame and make the fine adjustments. Note:  Look for cropped corners without a slide inserted.

 

After you’ve determined everything is aligned, mark the location of your 2”x5” base on the 4” x 8” base.    I used a couple of wood screws and fender washer, located a 3/8” or so away from the 2”x 5” to clamp and hold the piece in position.  It also allows the camera to be easily removed and adjusted.

 

Now that the camera is mounted and properly aligned you will need to turn your attention back to the projector’s lamp.   You’ll need a bright, cool and near white source.  I stuck with the florescent bulb mounting it with plumber’s strapping to the frame of the projector.  I experimented with a few different types of light diffusers and found an etched glass diffuser form an old under counter 2” halogen fixture worked great.  You might find the white plastic diffusers used on recessed lighting work as well; you can buy a 2’ x 2’ piece for 2 to 3 dollars at your local home improvement store.  Whatever you use will need to be placed between the condenser lens (thick lens, just behind the slide) and your lamp.  Make sure you get even lighting across the slide and the filament or tubes of your lamp don’t show up in your recorded images.

 

A few other things to consider.  Use a cool light source or one than doesn’t produce a heat problem for the slides or projector.  You’ll want to be able to disconnect your projector’s fan while recording your slides to eliminate vibration.

You might want to consider shielding your lenses from stray ambient light.  I used cardboard and construction paper to cover any exposed areas thinking it may prevent lens flares and screwing with my camera’s exposure system.

 

At this point you can start recording your slides manually, take a picture, then press the slide advance, take a picture then press the slide advance…  until done.

I did this for about 1000 slides and 2.5 hours before it dawned on me I had 5000 more to go.

Being that I’m always looking for an easier way to do things, I decided it was time to kick it up a notch.

Looking at what needed to be done to automate the task; I figured an electro mechanical solution was the most efficient and straight forward.   Although an electronic solution would be far more modern and Geek, it would need a week’s work, designing and parts chasing.  I would’ve also had to disassemble the camera which was still in warranty.  Maybe in 6 months I’ll consider doing a Stamp controller for my 20k negatives.  Besides I had everything on hand to do an electro-mechanical solution and it would be fun to watch even if it didn’t work.

 

The key was to find a gear motor that ran slow enough. I needed something in the 1-4 rpm range.  Something like a rotisserie motor.  I knew I had a battery operated one from an old propane grill.   As it turned out I found a 2 rpm gear motor I had purchased surplus many years earlier for a couple of dollars that would work even better.

 

I’ll not go into all the details of how I constructed the cam timer.  Basically it was constructed using easily located items.  The shaft is a ¼-20 x 3” carriage bolt I cut the head off.  The large disk was cut from an old circuit board using a hole saw.  I chucked the disk into a drill and like a lathe I trued it with a piece of sand paper.  The smaller disk was an aluminum blank left over from another project which was trued just like the larger disk.  I used nuts and washer to fix the disk on the timer shaft.  I cut the 2 cam lobes from some scrape aluminum and then screwed them to the disk 180 degrees apart.  They were later filed down to the required dimensions to focus and trip the camera.  I installed 2 trip studs 180 degrees from each other on the smaller disk for cycling the slides.

A piece of 3/16 automotive fuel line was used to couple the shaft to the gear motor’s shaft along with a hose clamp. The rubber coupler also helped to isolate motor vibration.

The 2 brackets shown are just everyday brackets you find at any hardware store.  The flat bracket I bent and drilled, allowing it to be mounted to the side of the motor base and act as the fulcrum for the shutter lever.

The lever is .2” x .4” brass tubing purchased at a hobby shop (K&S metals display, some ACE hardware stores carry as well). I ground a taper in the brass tubing so it would straddle the cam disk.  A 4-40 adjustment screw was installed at the camera’s end of the lever to adjust out any slack in the linkage.

I used a 4-40 x ¾” screw locked down to the bracket with a nut, acting as a stud for the pivot.  I then used an over sized washer to space the lever away from the lock nut, followed by a washer and 2 nuts as a lock nut to secure the lever on to the pivot.   NOTE.. make sure the hole you drill in the lever has little play.  The linkage between the cam disk and camera’s trip button needs to be tight and with no slop.   The difference between focus and shutter trip is only .010 to .020”.

The motor was mounted using plumber’s strapping and was isolated using pieces of rubber from an inner tube.

I used a lever switch (RS used to carry) mounted to an “L” bracket to switch the slide cycling.

 

Wiring ...

 

This may vary with brand of projector.   My GAF 2680 had 3 voltages bouncing around inside.  The lamp and fan were 110vac.  However to my surprise they were using the fan’s field windings as a transformer which had secondary voltages of 24vac and 3vac.

What this meant was when I disabled the fan; I lost power to the slide cycling motor (24vac) and the 3vac was used for the projector’s focus motor which I didn’t need.

 

The simplest solution was not to provide any power to the projector and provide only the 24vac to the slide cycling motor and the timer motor, plus the lamp already had its own power cord.

 I used a 24vac 700ma transformer to power the slide motor and then rectified the 24v to operate the dc motor timer.  I put a 400ohm rheostat in series with the timer in order to vary its speed if necessary.  NOTE.. my dc motor only required 30ma to run,  which was less than 1 watt.

 

Once everything was in place and aligned, I began filing down the cam lobes.  NOTE: Don’t run your timer motor during this step.  You could damage the camera if to much force were exerted on the shutter button.   I simply loosened the nuts holding the disk in place just enough to allow them to rotate while I filed and tested.

Helpful Tip:  Run your timer at whatever its max voltage is and determine its max rpm.  You can then divide your disk into 4 quadrants with a marker.  Example, if your motor runs at 4 rpm max then each quadrant represents 3.75 seconds at 4 rpm.  60sec / 4rpm = 15 sec/rev       15sec / 4 quadrants = 3.75 sec / quadrant.  Knowing this, you can use your quadrant as a scale to file the dwell time for your cam lobes.    My camera needed approx 1.5secs to focus before the shutter was tripped.   So the focus cam lobe was about half a quadrant long and the shutter trip was nothing more than a .015 inch rise at the very end for a fraction of a second.

Another tip is to place a piece of rubber between the lever adjustment screw and the shutter button.  It will work as a cushion and protect your shutter button from wear.  I thought about using a spring but it was a little more involved than I had time for.

 

While cleaning out some old junk to make room for new junk, I came across my 6,000+ collection of slides.  I had made a half assed attempt at scanning them 5-6 years earlier using my transparency equipped Microtek E6 scanner.  But because it was such a painful experience (it took on average 30-40 minutes to scan at 1200dpi 16 slides) I shelved the slides in hopes something better would come along.  Yes I know Nikon and others make their over priced, slow as molasses terapixel scanners with a color depth of infinity.  So what?  After all I’m talking about digitizing 30+ year old slides and negatives here.  Father time has taken his toll on them to the point some are so faded they barely have any color at all. Some of those that still have color, look as if they were taken on the planet Mars.  Considering that I really needed to make a serious effort this time, I did a little research only to discover that there still isn’t any cost and time effective solutions to batch process slides or negatives.

 

So I started brain storming and goofing around with my slide projector and a cheap ($90) 5 megapix camera.  I soon discovered not only was it fast (approx 2 sec / slide) but the results were 10x better than the E6 scans.  But the best thing  of all was the projector was a natural for handling the slides.

 

Which gave me the idea for the following project.

Merging a 35 year old GAF 2680 projector to a no-name $90 Emprex 5 mega pixel camera.

 

 

Click on photo to see the original. This photo is representative of the result I got.  This was a 30+ year old slide shot on kodachrome 64.  Dust and degenerating cardboard slide carriers contributed to the black specks you will see in some areas of the picture.

Tips ...

1.. If your camera allows you to manually set its white balance, then you might try setting it to your projectors light source before processing any slides.  Any color shifts that are inherent in the slides can be post processed with batch photo processing software. (Corel Photo Paint Pro X has an Auto Enhance feature for large batches of photos)

 

2.. You might find you can speed the cycle times up if your camera has a manual focus feature. 

 

3..  I used a 1GB memory card which would hold approx 360 photos.  When it filled to capacity I would just plug in my USB cable and dump its contents to my computer, which would take about 5-6 minutes. 

 

4.. I found I needed to blow the projector’s optics off  every 200-300 slides.  Most of the contamination was caused by the cardboard carriers.  Be careful when blowing the dust of the optics.  The cans of  Dust Off  when tipped slightly will squirt some sort of liquid out that will fog your lenses and will have to be cleaned off with lens cleaner.

 

5.. Check your cassettes for any vertical slides making sure to rotate them 90degrees to avoid having them cropped by your camera.

 

6.. If you are like most people you’ve probably got a bunch of bad slides.  I used the ones that were nearly transparent as batch markers.  I would write on the slide itself with a whiteboard/transparency marker the batch number and insert it into the slide cassette.  This way if I discovered in post processing the group was real dirty and needed to be cleaned and reprocessed, I could trace them back to the source slides.

 

7.. My gear motor ran 1.5 rpm at 2.8vdc and would increase to 4.8 rpm at 24vdc. Because I could vary the motor voltage with the rheostat and I had 2 cycles per revolution, I could vary the processing speed from 180/hr to 576/hr. I typically ran the process at 450/hr.

 

8.. I think it would be pretty easy to add cut of counter or timer which would shut down the system at the end of a cassette.

     I used a windup kitchen timer to remind me to check on it every 14 minutes, the time it took to process 100 slides.

 

Conclusion…

The project for me was by far the most productive I’ve done in a while.  It went together fast in approx 6 hours and the result were as good as I expected.  The only real surprise was the dust. 

I know its not the most eloquent mod, but in words only my mentor can express “Git-R-Done!”

 

 

Well its time for me to return to cleaning my junk out and thinking about how to convert all my negatives.

I hope you find the mod as useful and effective as I did.

 

If you have any questions or comments fill free to drop me a note

Jeff Barney

6000+ SLIDES TO DIGITAL IN 14 HOURS

Is it possible?

Click here for video   It’s a 9MB file and will take 1-2mins to dl.  Or you can right click and save to your machine.