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Alexander Nikishin
03-27-2007, 11:03 PM
I remember the still posted of Franky shooting a chroma chart with a Nikon AF 50mm prime.

I was wondering whether or not the barrel's distance markings were accurate when mounted to Red?

Gabriel C.
03-27-2007, 11:13 PM
I want to know as well.

Brook Willard
03-27-2007, 11:33 PM
As in focus witness marks?

Alexander Nikishin
03-27-2007, 11:48 PM
Yesir.

Evin Grant
03-28-2007, 12:26 AM
It occours to me that if they were acurate it was a fluke. Frankie is a test bed camera and I can't imagine they did much more than bolt that lens mount on for the test. It most likely would not have been shimed or properly adjusted for flange focal distance.

Alexander Nikishin
03-28-2007, 12:55 AM
Then a better question would be, has the flange focal distance of the Nikon mount been set to allow for accurate barrel marks?

Stephen Williams
03-28-2007, 11:54 AM
Hi,

If you take some Nikon lenses, their FFD is not accurate in motion picture terms. They should be collimated, then you will have a good chance of the focus marks lining up.

Does anybody know where the measure point is with Nikon Lenses?

Stephen

Evin Grant
03-28-2007, 01:05 PM
The film/sensor plane just like movie cameras. If the mount is made to precise enough specs the focus should line up perfectly assuming the lens has been properly collimated, hence why I suggest getting a CLA. Although I wouldn't mind if Red made the mount slightly short, this would allow some wider lenses to focus past infinity. This can be necessary in some instances where heat and other atmospherics put infinity farther away than it's mathamatical distance. On 35mm film you wouldn't have seen this but at 4K you would.