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View Full Version : Ebonys rise/fall zero position on front standard



Aender Brepsom
13-Aug-2007, 02:04
Hello,

on the left metal part of the Ebonys' front standard, there is a red dot to align with the wooden part that holds the lens board, which has a white dot. I guess, this is the zero position of rise/fall.

My question is: Is this zero position for lens boards where the hole is drilled in the centre or for those where it is a little further down the centre of the lens board?

With lenses with a large image circle, this might be quite irrelevant, but with a lens that would only just cover the 4x5" format, this probably makes a huge difference and may result in vignetting (for example with a 55mm Apo-Grandagon, 163mm IC).

Thank you for your help.

Aender

Mattg
13-Aug-2007, 04:18
On a 6x9 it was about 1cm off centre and seemed to have been made for Technika-style offset boards. If you're using generic boards it may be hard to be 100% accurate by relying on the dots. The best way to be sure is the remove the back and sight the lens position with the standards as close together as possible, then mark the front standard.

BradS
13-Aug-2007, 06:43
Hello,

on the left metal part of the Ebonys' front standard, there is a red dot to align with the wooden part that holds the lens board, which has a white dot. I guess, this is the zero position of rise/fall.

My question is: Is this zero position for lens boards where the hole is drilled in the centre or for those where it is a little further down the centre of the lens board?

With lenses with a large image circle, this might be quite irrelevant, but with a lens that would only just cover the 4x5" format, this probably makes a huge difference and may result in vignetting (for example with a 55mm Apo-Grandagon, 163mm IC).

Thank you for your help.

Aender

I have an RW45 with the alignment dots that you mention. They are very clearly designed for the lensboards with the hole offset from the center. This much is clear if you install a lensboard without a lens, align the dots and move the standards together. Look through the center of the hole in the lensboard at the grid pattern on the ground glass (look through the camera backwards) and you'll see.

Aender Brepsom
14-Aug-2007, 05:07
Thank you both for your helpful replies.

Cheers