Accura Variable Magnification Duplicator
The Accura Variable Magnification Duplicator is a slide duplicator designed to be mounted on a 50mm lens.
Accura Variable Magnification Duplicator image by steevithak (Image rights) |
Description
The Accura Variable Magnification Duplicator is a slide duplication tool for use with 35mm film cameras. Unlike other slide duplication units, it had no internal optics. It was designed to attach to the filter mount of a 50-55mm lens. An extension tube or bellows was also needed to adjust the focus range of the 50mm lens. The duplicator itself has a further adjustment tube that can alter the magnification of the slide from 1:1 to slightly greater magnifications.
The camera-side of the duplicator has Series VI filter threads. Each unit included a Series VI to Series VII step-up adapter ring. Later units also included a Series VII to 52mm or 55mm adapter. Color correction filters can be place inline between the lens and duplicator if needed for use with the light source. This type of mounting system made the duplicator both less expensive and more versatile than units with dedicated optics.
Another advantage of lens-mounted duplicators like this one is that they can be adapted to work with modern crop-sensor DSLR cameras. The majority of slide duplicators with dedicated 1:1 optics cannot be used on crop sensor DSLR cameras because the image produced will be cropped, showing only the center area of the slide. But with a lens-mounted unit, alternate lenses, filter adapters, and extensions can be improvised to produce usable results.
Light Source Recommendations
To illuminate the slide, a flash unit is placed in front of the white plastic light diffuser. A 500 watt 3200 K light source was recommended if a strobe is not available. With appropriate filters or white balance corrections, nearly any light source may be used. The following table is derived from advice in the original instructions for the unit and provides light source types, distance, ISO, and shutter speed suggestions. For aperture settings, it recommends following the guidelines provided with your bellows or extension tube set.[1]
Light Source | Distance | ISO | Shutter Speed |
---|---|---|---|
500 Watt 3200 K | 6 inches | 8 | 1/4 |
500 Watt 3200 K | 6 inches | 25 | 1/15 |
500 Watt 3200 K | 6 inches | 40 | 1/25 |
500 Watt 3200 K | 6 inches | 125 | 1/60 |
40 Watt/Sec Strobe | 12 inches | 125 | 1/60 |
40 Watt/Sec Strobe | 9 inches | 64 | 1/60 |
#211 Enlarging Lamp | 6 inches | 8 | 1 sec |
Photos
image by steevithak (Image rights) |
image by steevithak (Image rights) |
image by steevithak (Image rights) |
image by steevithak (Image rights) |
References
- ↑ Accura Variable Magnification Duplicator instruction manual