using a digital back on a 4x5

[james zhou]

Hi I am thinking of buying a used Hassel digital back, but I don't know much about medium digital camera backs. I know that they can be used with 4x5, but how is exposure controlled? Is it in the back or by the lens shutter? ON a digital back there many electrical contracts, but on a 4x5 camera, there is none. Could anyone advise me a little bit? Thanks! jim

[Gene McCluney]

Normally the "one-shot" type of digital back such as the ones for the Hasselblad, when used on a 4x5 camera are controlled by a sync-cable from the camera lens flash sync terminal. The exposure is done with the camera lens aperture and shutter speed, just like for film..however you DO have the option for setting the back for different ISO settings, which of course would influence exposure.

If you are considering a SCANNING BACK such as the models made by Betterlight, and by the way, the scanning back is the only digital medium for 4x5 that comes close to the 4x5 image area, then all the control for the back is done through a tethered control box and attached computer (laptop or desktop computer). You still need to set the f-stop on your lens though.

[james zhou]

Thanks! Gene. I thought about a scan back as well. Jim

[Peter De Smidt]

We use Phase One backs on both Hassleblads and Sinar P2s. The Sinars have special sliding backs, with a ground glass the size of the sensor on one side and the back on the other. At least with our backs, you really need to shoot at the lowest sensitivity, i.e. EI 50, or quality really suffers. Also be aware that tilts and swings can cause a green on one side and magenta on the other side color tinge. Finally, movements with a digital back need to be more precise than with film. As a result, older film cameras, even really good ones, aren't as ideal for working with the digital backs as the newer view cameras designed with digital in mind.

[james zhou]

Thank you! Peter. jim.