Digital Back Adapters: Less Expensive Alternative

[neil poulsen]

I've been pondering about these really expensive sliding backs that have both a focusing screen and an adapter that holds a digital back. When photographing, one slides back and forth between the screen and the back. They sell for upwards of $1800. One advantage over less expensive adapters that hold only the Digital back is that they protect the image sensor and help prevent dust from landing on the sensor. But even then, the image sensor can become vulnerable to damage, when the back is removed to change orientation. (Vert/Hori.)

Wouldn't it be much less expensive and more functional just to incorporate a darkslide into adapters that only hold the digital back??? With such a setup, at no time would the digital back be exposed to the environment, even when changing orientation.

I can see where the sliders offer a faster transition between focusing and capturing the image. But for a view camera, I'd say that this is needed for a minority of cases.

Recently, we were looking at what was available in a basic, 4-banger pickup truck, and I discovered that neither Ford nor Chevrolet offer one of these for sale. No, if you want a pickup, it has to be the deluxe model with cruise cab, etc. Well of course, they make a lot more money this way. Why provide for basic needs, when overkill results in a higher profit?

As I said, just pondering.

[vinny]

for under $600? http://www.ebay.com/itm/Kapture-Group-Sliding-Back-Adapter-for-Cambo-Hood-Hasselblad-V-29249-/370981601736?pt=US_Viewfinders_Eyecups&hash=item56603a01c8

[Bob Salomon]

Neil,

Those digital backs are low to mid 5 figures just for the back. Imagine holding the GG back in one hand and the digital back in your other hand, while switching betwen them and having to sneeze. Or having the client bump the camera when you release the latch or any of a myriad other things that could happen during a shoot that could result in a dropped back.

Next consider, digital is a perfect medium. Unlike film which has multiple layers of emulsion and sags digital is one pixel deep (save the Foveon) and is perfectly flat. So when you slide and shift from the side doing digital to the Gg side the two have to be in much tighter alignment then they do with film.

That is what you are paying for. Convenience, safety and precision.

[8x10 user]

Emulsion layers versus Bayer grid.

[brian mcweeney]

Also the sliding back is used for stitching. With pre sets to register the back in place.
There is no "wiggle room" using a digital back on a view camera. Everything has to be precise.

[neil poulsen]

Also the sliding back is used for stitching. With pre sets to register the back in place.
There is no "wiggle room" using a digital back on a view camera. Everything has to be precise.

That's a good point. Hadn't thought of that. Didn't realize. Good idea! :D

Still, if I had something like I've described, I'd be abundantly careful. Put one down, pick other up. I'd also have insurance!

I think both would have their advantages.

[neil poulsen]

Neil,

Those digital backs are low to mid 5 figures just for the back. Imagine holding the GG back in one hand and the digital back in your other hand, while switching betwen them and having to sneeze. Or having the client bump the camera when you release the latch or any of a myriad other things that could happen during a shoot that could result in a dropped back.

Next consider, digital is a perfect medium. Unlike film which has multiple layers of emulsion and sags digital is one pixel deep (save the Foveon) and is perfectly flat. So when you slide and shift from the side doing digital to the Gg side the two have to be in much tighter alignment then they do with film.

That is what you are paying for. Convenience, safety and precision.

This is also enlightening. I think that the tolerances could still be kept close. Just a matter of precision machining.

One thing, if there's a digital back in my future, I wouldn't want to go much above 16x20 in the final image. Schneider told me that in the mid-20mp range, digital optics aren't really needed, especially if the focal lengths exceed the diagonal of the sensor. But above 30mp, one needs the special optics (at least for wide-angles) and finer tolerances to obtain the sharpness of which the backs are capable. Otherwise, it's kind of like using an Apo enlarging lens without a glass carrier.

[Bob Salomon]

This is also enlightening. I think that the tolerances could still be kept close. Just a matter of precision machining.

One thing, if there's a digital back in my future, I wouldn't want to go much above 16x20 in the final image. Schneider told me that in the mid-20mp range, digital optics aren't really needed, especially if the focal lengths exceed the diagonal of the sensor. But above 30mp, one needs the special optics (at least for wide-angles) and finer tolerances to obtain the sharpness of which the backs are capable. Otherwise, it's kind of like using an Apo enlarging lens without a glass carrier.
First, every enlarging lens should lways be used with a glass carrier and a properly aligned enlarger if you want the quality the lens is capable of.

Next digital lenses and a digital view camera will give best results for any size image in digital. And when you consider the cost of a digital back a digital camera and lenses is the least of the costs involved.

[LarryT]

When I recently purchased a used Linhof digital back adapter for my P25 back, the previous owner told me he had tried one of the cheaper version from China available on eBay. The cheaper version, he told me, was just not as well finished and did not seat as well in the rear standard as the Linhof one.

[VictoriaPerelet]

Dending on digital back - you do not really need groundglass at all. Backs with "life view" let you focus on laptop screen. Once you get used to it you will understand that no loupe can focus better than high res digital magnification:)

Most of moden backs can do that. In case if somebody will "complain" about extra weight of laptop - there are very compact and rugged laptops.

[Drew Wiley]

In the real world, things don't always work out so neatly. Will a more cumbersome back somehow tug on your camera and slightly flex it out of ideal focus, for instance? If the film plane of the camera itself well enough machined? Don't take that for granted either. When in doubt, measure with precision tools. Will it hold
those tolerances over time. Maybe, maybe not. ... But with the reduced size of the sensor compared to film, focus itself, along with movements, are all going to become a lot more fussy. The risk of a complex back being more susceptible to the elements has already been pointed out. I'm a film guy and don't even pretend to
be a digital phototgrapher. But I do understand the implications of proper alloys and machining quite well, and while there might indeed be some brilliant exceptions
to the rule, the rule itself is that you generally get what you pay for.

[neil poulsen]

It's hard to get more cumbersome than a slider. And talk about slop, as the slider moves back and forth, and as the bearings wear. Of course, it would HAVE TO BE PRECISION MADE to avoid variation in the image plane. No wonder sliders are expensive.

My goal is 16x20 color. I like that size. In that size, one can stay under 30mp and do just fine with regular optics, except maybe for a 35mm digital lens. I can get a regular Arca Hasselblad adapter on which to mount the back and trade back and forth between some sort of focusing device and the digital back.

As to my ponderings, it would be nice to have a darkslide in the adapter to protect the digital back as I go back and forth.