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Ben_4657
1-Aug-2005, 03:22
Dear all,

I have received my new Ebony 45SU.

By tilting the front standard I have noticed I lost the focus on the middle line. It seems that despite a center tilt the focus is lost.

I also noticed that because the linhof board are drilled a bit off center, the axis of rotation of the front standard does not intersect the lens axis (lens axis is between 5 and 10 mm below the line that rotates).

Is that off center drill made on purpose on Linhof boards ?

Has it something to do with the nodal point ?

Should I get Bromwell boards (center drilled) to get an actual axis tilt on my Ebony ?

Thanks

paul owen
1-Aug-2005, 05:49
Hi Ben. Congratulations on owning the best camera money can buy :) OKAY, I'M READY FOR THE ONSLAUGHT!!!!!!!

In reply to your questions:

1. What you are describing with front centre tilt is normal. If you focus on the central area of the screen then tilt the lens forward the foreground will pop into focus but the central area of the screen will appear slightly soft. You then refocus the centre and tilt the lens and repeat until both areas are sharp.

2. The hole being drilled off centre is "traditional" and sinply allows some camera to have a front "fall" built in - don't worry - you don't need central-drilled lens panels.

3.The real benefit of the 45SU is the rear assymetrical movements. To use these you simply focus on the left hand (vertical) broken line on the screen - doesn't matter whether the area you are focussing on is foreground or background - then swing the back until the image on the opposite vertical broken line is in focus - and that's it!! Everything is in focus! To apply rear tilt you simply focus first on the bottom broken line then tilt the rear until the area on the top broken line comes into focus - and it s all done!

Hope this helps! Paul

Michael J. Kravit
1-Aug-2005, 15:19
Congratulations on your new Ebony. I also have an 45SU and absolutely love it. In all honesty it is without doubt one of the finest 4x5 cameras available today.

As Paul menyioned, Assymetrical tilts is the feature of this camera that really makes it shine. Learn to use them and you will streamline your approach. There is a paper on the Ebony website that explains the process in detail.

Enjoy, and make lots of great images.

Mike

Brian Ellis
1-Aug-2005, 20:55
I believe the Linhof board has the hole cut slightly off center because of the way the front standards of Linhof cameras are designed. With that design putting the hole off center actually centers the lens and film on a Linhof camera. When Linhof boards are used on other cameras the off-center hole puts the lens slightly off-center in relation to the film. If you wanted to perfectly center your lens and film on your camera with the Linhof board you should use a few mms of front rise every time but the difference is so small it really isn't worth the trouble.

Donald Hutton
2-Aug-2005, 11:38
The Ebony is desgned to use the "off-center" style Linhof boards - I recently checked the "zero" position on my SV45U - it is perfect with the off center style board (which makes sense - Ebony branded lensboards are off center too).

Brian Ellis
2-Aug-2005, 15:11
Don - Yes, you're right. I've owned two Ebony cameras and a couple Ebony lens boards. I should have remembered that they are designed to take the Linhof boards. I was really focusing more correcting the suggestion that the off-center hole is there to build in some front fall.

Jeffrey Scott
3-Aug-2005, 19:58
You will notice that the pivot point for the lensboard is actually above the lock knobs, so in effect there is a bit of focus shift in the image. I too, love my 45SU, great choice you made!