May 12 2012
Though I no longer own a slide projector, I have about 2,000 photographic slides (also known as “transparencies”). Some are nearly 40 years old, and many are showing early signs of senile decay. Digitizing this collection would preserve it, of course, but having the job done commercially would be prohibitively expensive, and purchasing a high-resolution slide scanner wouldn’t be much cheaper. The upshot? I’d pretty much resigned myself to seeing my slide archive slowly fade away. Then it struck me that I already had just the tool I needed to save it: a digital SLR.
Well, OK. I needed a few more things. Here’s the whole list:
- Digital SLR
- Macro lens
- Cable shutter release
- Translucent backboard
- Binder clip
The digital SLR posed no problems. My Pentax K200D fitted the bill. But I don’t own a “proper” macro lens. I do have a Raynox DCR-150 converter lens, however, and it pairs nicely with my Pentax 55-300 mm zoom telephoto. The translucent backboard took a little more ingenuity, but a rigid poly cutting board from Walmart proved ideal. It diffuses the incident light admirably, preventing background detail from “printing through” onto my digital slide copies. If you have a light table or other “clean” light source, however, a transparent backboard should work equally well. I haven’t tried it, but if you have, please drop me a line to tell me how the experiment went.
For the slide-holder-cum-mask I turned to a sheet of cardboard that had once done duty as the backing for a writing tablet (another pre-digital-age implement!). I traced an outline of a slide on the cardboard, then cut a transparency-sized window,…
…before finishing it off with two tapered cardboard tracks that I taped to the cardboard mask. (I left the turned-up ends open to facilitate inserting slides, but this proved unnecessary.) The tracks and inked grid lines made it easy to center each slide over the window:
The moment of truth had arrived. After clamping the cardboard slide holder to the backboard with a single binder clip, I was ready to put my brainchild to the test. For a light source I used my office window. I just leaned the backboard against the glass. (Since I wanted diffuse light, I chose a cloudy day.)
Next, I mounted my camera on a sturdy tripod and placed it close enough so that the image of the slide all but filled the viewfinder:
I took pains to ensure that the plane of the camera’s sensor was parallel to the slide’s film plane. (If this isn’t done, it will prove impossible to get all of the slide in sharp focus.) Once I was satisfied that everything was in readiness, I set the camera to Autofocus mode and selected aperture priority at ƒ/8. I also bracketed exposures by EV, while using a cable release to minimize vibration.
Here’s my very first digital copy, unchanged except for re-sizing to fit this page:
The original slide was dark, with a rather soft focus, and this initial effort proved instructive. In subsequent attempts, I took more care to fill the frame and ensure that the image was properly centered. My technique improved rapidly. Before long, I was digitizing slides at the rate of one or two a minute, with very little time lost to bracketing.
And I’m pleased with the results. Though the digitized images can’t quite equal the sharpness of the originals, I can recover most of the lost ground in my digital darkroom. (I can also correct any errors in focus or exposure in the original slides. That’s a bonus.)
But you don’t have to take my word for it. See for yourself, beginning with the final, corrected copy of the slide I used in my first trial shot. As luck would have it, this slide—photographed at dusk along the margins a forest rill, without a tripod—was one of my earliest attempts at employing deliberate blurring to capture the fluid essence of moving water:
And now here’s another digital copy. The original slide was also shot late in the day—a winter’s day, obviously—when the curling ribbon of snow at the bottom of the playground slide caught my eye:
Finally, check out this shot of student climbers learning the ropes in the Wenatchee Mountains:
The bottom line? My old slides may be doomed to fade away, but their digital copies will live on. And while my DIY slide copier may not produce images to equal those from dedicated slide scanners, they’re good enough for me. The price was right, too!
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