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Digizoom Back Focus

Published : 16th August 2004


After the recommendation of a rental house, I checked on the site the new digizoom from BandPro.

I have a question...it says that is compatible with the sharp max...but, how is the procedure to make the back focus adjustment with the zoom? Is it possible to do it with any focal length?

I like the Optimo zoom, but it's impossible to work with in handheld mode. Is this zoom smaller or lighter? Is out there any brochure?

Pol Turrents
DoP Spain, Barcelona



Well I guess I must step in here.

Pol wrote :

>How is the procedure to make the back focus adjustment with the >zoom? is it possible to do it with any focal length?

Set the lens to infinity and wide open, the sharpmax calibrates the infinity focus which should track the full length of the zoom but check a few focal lengths to be sure. On the DigiZoom the scale is 100% accurate so calibrating anywhere will work if the lens is focussed at infinity. It is easier on the long end because the Seimans Star pattern is largest

This should work with any lens that has a fixed infinity focus. For those that don't pick the centre of the infinity mark.

Pol wrote :

>I like the Optimo zoom, but it's impossible to work with in handheld >mode. Is this zoom smaller? or lighter?

2 kilo 4 cm MUCH SMALLER MUCH LIGHTER
A brochure is available, it will be on the website soon
The Digizooms will be shown at Cinegear, IBC and Cinec

Michael Bravin
Chief Technology Officer
Band Pro Film & Digital
www.digizoom.com



Michael Bravin wrote :

>On the DigiZoom the scale is 100% accurate so calibrating anywhere >will work if the lens is focussed at infinity.

But wouldn't you want to adjust back focus at the shortest focal length possible, because a longer focal length will have greater depth of focus, and therefore appear to be properly adjusted over a wider range?

Certainly when you check collimation on a zoom on a (dreaded single sensor, like) film camera, you always check wide angle, wide open, at infinity.

But I may be missing something...

Jeff "currently redesigning our back focus adjustment mechanism" Kreines



Jeff writes :

>But wouldn't you want to adjust back focus at the shortest focal length >possible, because a longer focal length will have greater depth of focus, >and therefore appear to be properly adjusted over a wider range

Mr Kreines, you are absolutely correct and now I know why replying on CML after several intoxicants may cause technical difficulties but hey it was Sunday afternoon.

Michael Bravin
Chief Technology Officer
Band Pro Film & Digital



Michael Bravin wrote :

>Mr Kreines, you are absolutely correct and now I know why replying on >CML after several intoxicants may cause technical difficulties but hey it >was Sunday afternoon.

You need one of those new keyboard-mounted breathalysers

Jeff Kreines



>You need one of those new keyboard-mounted breathalysers

Forget the Kinetta...Rush this into production and you'll retire rich ...Jeff!

George Hupka
Director/DP
Downstream Pictures
Saskatoon, Canada



George Hupka wrote:

>Forget the Kinetta...Rush this into production and you'll retire rich...Jeff!

Better, how about a mood-sensitive send delay -- it you're cranky, your outgoing mail is held for 12 hours for re-evaluation.

Of course, that would take all the fun out of the internet.

Jeff "of course, I don't need one!" Kreines