Film-Tech Forum ARCHIVE: B&L anamorphic diameter

This is topic B&L anamorphic diameter in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Phil Housh (Member # 1721) on 05-04-2007, 05:58 PM:

Can anyone tell me what the diameter size is on a B&L anamorpic? [Confused]

Posted by Tim Reed (Member # 137) on 05-04-2007, 06:54 PM:

There were at least two different sizes in the red ring variety, for 4" and 2" backups, respectively.

Posted by Steve Guttag (Member # 268) on 05-04-2007, 07:11 PM:

As Tim said there were two... the type 1 had a 4" (101.6mm) rear and the Type II had a 2-25/32 (70.6mm) rear. Or do you mean thread pitch? B&L uses the popular 36TPI versus Kollmorgan that used 32TPI.

Steve

Posted by Phil Housh (Member # 1721) on 05-04-2007, 07:14 PM:

Guess I forgot to give the back-up size. It is 2 inch. Sorry about that.

Posted by Phil Housh (Member # 1721) on 05-05-2007, 11:51 AM:

Steve,
This is the info I got from Widescreen Museum: Type I is 4.25" diameter with 70.6mm rear. Type II 5.25" diameter with 101.6mm rear.

Posted by Tim Reed (Member # 137) on 05-05-2007, 12:54 PM:

You mean you were asking about the fronts of the lenses? That's not normally used for anything, unless you plan on making a reverse-anamorphic adapter?

Posted by Phil Housh (Member # 1721) on 05-05-2007, 03:47 PM:

No, I was interested in the backs.

Posted by Steve Guttag (Member # 268) on 05-05-2007, 04:39 PM:

It is possible I got my type 1s and type 2s backwards. However, 70.6mm = 2-25/32" and 101.6mm = 4" That you can bank on.

Posted by Rick Deleau (Member # 4212) on 05-08-2007, 10:21 AM:

Hi

on the topic of Lens I a have a Kollmorgen Lens Selector (slide ruler) I'm trying to figure it out! I have a 44' throw on to a Maximum of 25' wide scope screen, if I could email someone a copy of this (slide ruler), perhaps you could explain it? or skip the lesson and just tell me the scope, and flat size.

Thanks rick

Posted by Alan Gouger (Member # 543) on 05-08-2007, 11:07 AM:

Rick

Looking at my lens calc you will need a 67mm or 2 1/5" to 2 3/4" back up.

Posted by Mark Gulbrandsen (Member # 72) on 05-08-2007, 03:22 PM:

Philio... You have E-Mail....
Mark

Posted by Phil Housh (Member # 1721) on 05-08-2007, 04:30 PM:

Thanx Mark! [beer]

Posted by Alan Gouger (Member # 543) on 05-08-2007, 06:02 PM:

Rick

I forgot to mention, go to the "Manuals" section of this form to the left and choose software. There's a nice lens calc download. Very easy to use.

Posted by Rick Deleau (Member # 4212) on 05-08-2007, 09:41 PM:

Thanks Allan