Unique BNC Rack Over Alignment Tool

~
Feel free to discuss any topic related to the Mitchell Camera. Both 35 mm and 16 mm models are welcomed here. Also consider posting topics of other major motion picture cameras that you feel are important to the development of the Mitchell Camera.

Update: You may have noticed that we have returned to just one category as opposed to dividing the forum into 7 different areas. Apparently, it was an unpopular change and returning to the old format will allow posters to find their submissions more easily.
~
mitchellbnc
Posts: 57
Joined: Wed May 15, 2013 10:03 am

Unique BNC Rack Over Alignment Tool

Postby mitchellbnc » Wed Aug 27, 2014 12:15 pm

Hello members. One of our members, Bruce Morgan, gave me permission to share these photos and a link to his eBay store in case you are interested in the purchase of this unique rack over alignment tool for your NC/BNC. When this item sells if will live on in this thread to document this rare factory item.

http://stores.ebay.com/brucetroy-CINEMA ... 7675.l2563

In aged but complete condition. May have been used at Mitchell Company or at a camera department at the studio. I have used Mitchell Rack Over Cameras for over 15 years and this device was used to confirm alignment of the brass stops on the L plate.

1 - THE CAMERA BOX WAS RACKED OFF
2 - THIS DEVICE WAS RACKED ON
3 - THE GROUND GLASS SIGHTING ELEMENTS WERE USED TO Align the rack over tool and the ground glass cross hair target through the taking aperture of the L plate. After rectification alignment was done the brass gibs or stops were tapped or moved into place on the L plate so that when reintroducing the camera box the camera would rack over properly.

Super size any photo by clicking on it.
Attachments
bnc alignment tool 1.JPG
bnc alignment tool 2.JPG
bnc alignment tool 3.JPG
bnc alignment tool 4JPG.JPG
bnc alignment tool 5.JPG

gadesro

Re: Unique BNC Rack Over Alignment Tool

Postby gadesro » Wed Aug 27, 2014 1:04 pm

What a fantastic tool for the Standard, NC and BNC Bruce! For those unfamiliar with the Mitchell Gib Rail system, I have included a couple of helpful orientation photos. This should help the novice because I know for me, this system really confused me way back when.

Randy
Attachments
gibs1.jpg
gibs2.jpg

brucermorgan
Posts: 17
Joined: Tue Aug 26, 2014 9:31 pm

Re: Unique BNC Rack Over Alignment Tool

Postby brucermorgan » Sat Aug 30, 2014 12:53 pm

Hello Randy
And thanks for that beautiful addition you made ! The L plate and camera box system with that long deep flarge focal distance was (ironically) well worth the trouble as Stanley Kubrick would prove years later by employing "exotic " non standard lenses to the BNC camera .
Great diagrams too Randy !
I will explain my hard road to understanding the rack over mechanism in one of my future articles .
Cheers
Bruce

winston_cornwall

Re: Unique BNC Rack Over Alignment Tool

Postby winston_cornwall » Sun Aug 31, 2014 8:01 am

Good day. This is a real find. If a major camera department had to have just two special tools to maintain a Mitchell it would be a machinist lathe and one of these little buggers. The Gib Rails themselves can be adjusted to and throw or "aligned" with tiny screws. The actual camera with the movement mechanism is then racked on to the L base. The slightest variation in perfect alignment will result in the focal plane being out of focus. Whilst It might take a critical eye to notice such a variance it is still an annoyance, what? But when your product goal is a crystal clear projected image, it can be a problem when perfection is the goal of the day.

Cheerio,
Winston

Guest

Re: Unique BNC Rack Over Alignment Tool

Postby Guest » Tue Sep 02, 2014 9:00 am

Salutation forum! That is one of the most cool Mitchell Camera tools that I have ever seen. How would you align the camera box to the L base without one of these? I've never seen one before but I find it hard to believe that the Michell Camera Corporation didn't offer an official alignment tool as one of the many accessories they offered for sale.

Mr. Jones

brucermorgan
Posts: 17
Joined: Tue Aug 26, 2014 9:31 pm

Re: Unique BNC Rack Over Alignment Tool

Postby brucermorgan » Wed Sep 03, 2014 3:34 pm

Hello !
You can eyeball camera gate-camera box alignment through the front of the L plate aperture
then you can tap in a setting of the brass stops on the rail base of the L plate .
But you are right -this device is superior .
Cheers
Bruce


Return to “General Discussions About the Mitchell Camera”



Who is online

Users browsing this forum: No registered users and 2 guests