Follow focus for zoom control at DVinfo.net
DV Info Net

Go Back   DV Info Net > Canon EOS / MXF / AVCHD / HDV / DV Camera Systems > Canon EOS Crop Sensor for HD
Register FAQ Today's Posts Buyer's Guides

Canon EOS Crop Sensor for HD
APS-C sensor cameras including the 80D, 70D, 7D Mk. II, 7D, EOS M and Rebel models for HD video recording.

Reply
 
Thread Tools Search this Thread
Old February 12th, 2010, 04:38 AM   #1
Regular Crew
 
Join Date: Nov 2008
Location: Oakland, CA
Posts: 112
Follow focus for zoom control

Not sure if this has been discussed already but has anyone tried using a follow focus rig for zoom control? I'm not thinking so much about the usefulness of zooming while recording but more so the overall ease adjusting focal length in the field.

If you have, did you also try to have another FF doing focus control at the same time? Can two FFs even fit at the same time?
Graham King is offline   Reply With Quote
Old February 12th, 2010, 04:46 AM   #2
Trustee
 
Join Date: May 2005
Location: Allen, Texas U.S.A
Posts: 1,117
I have tested my DIY gearless ff on my 80-200 zoom ring instead of the focus ring. It will give a smooth turn BUT the problem is most zooms arent parafocal.

Usually, we "traditionally" zoom in focus, and zoom out. And know that focus stays. This is not the case with still camera lenses.

Heres my ff.

DIY Gearless Follow Focus Test
__________________
Ted Ramasola
http://ramasolaproductions.com

Last edited by Ted Ramasola; February 12th, 2010 at 04:49 AM. Reason: correction
Ted Ramasola is offline   Reply With Quote
Old February 12th, 2010, 04:50 AM   #3
Regular Crew
 
Join Date: Nov 2008
Location: Oakland, CA
Posts: 112
Just found this page: Basic Mini Single Wheel Follow Focus - Dual Setup

Looks like a great way to go but I'm still wondering if two FFs could be used on the same side. Seems like this would be even more convenient because the right hand could stay on the hand grip and recording can continue uninterrupted (thinking about event and guerilla type shooting).

I'm thinking the main factor is having enough space for both wheels. I' suppose it depends on the distance between the focus and zoom rings on a particular lens and on the size of the wheel. Any ideas on which model might work best? Cavision, Chrosziel, Arri, or others?
Graham King is offline   Reply With Quote
Old February 12th, 2010, 04:51 AM   #4
Regular Crew
 
Join Date: Nov 2008
Location: Oakland, CA
Posts: 112
I'm aware of the parafocal issue but I can just imagine being able to adjust zoom and then quickly refocus because the other wheel would already be right there by your hand. Having the second wheel on the other side doesn't seem like a good solution to me for this reason.
Graham King is offline   Reply With Quote
Old February 12th, 2010, 04:56 AM   #5
Trustee
 
Join Date: May 2005
Location: Allen, Texas U.S.A
Posts: 1,117
Check this, he has it mounted on one side,

iDC Photo Store - Specialty gear for the photographer
__________________
Ted Ramasola
http://ramasolaproductions.com
Ted Ramasola is offline   Reply With Quote
Old February 12th, 2010, 05:05 AM   #6
Regular Crew
 
Join Date: Nov 2008
Location: Oakland, CA
Posts: 112
That's definitely along the line of what I'm taking about. However, can it only be used with these lenses:

EF 24-70mm f2.8L USM
EF 28-70mm f2.8L USM
EF 24-105mm f4L IS USM
EF 70-200mm f2.8L USM
EF 70-200mm f2.8L IS USM
EF 70-200mm f4L USM
EF 70-200mm f4L IS USM

I'd really like to have this capability on the 16-35 or 17-55. Also, I'm not too sure about the gearless design. Any experience with that?
Graham King is offline   Reply With Quote
Old February 12th, 2010, 05:09 AM   #7
Trustee
 
Join Date: May 2005
Location: Allen, Texas U.S.A
Posts: 1,117
No experience with that product. Only with mine where Its tricky to use on old lenses with the rubber rings already brittle and smooth, it works with focus and zoom rings with rubber rings that still "stick" or "grip" for lack of the proper word.

In cases where the focus ring don't have "traction" anymore, i added a belt that provided the traction for the gearless follow focus to "hold" on to.
__________________
Ted Ramasola
http://ramasolaproductions.com
Ted Ramasola is offline   Reply With Quote
Old February 12th, 2010, 02:45 PM   #8
Major Player
 
Join Date: Mar 2005
Location: Ontario, Canada
Posts: 916
We do have a few folks using the Durus Focus Gear Lever on their zoom rings. It essentially provides an outboard handle to whip zoom etc.

Cheers,
Dennis Wood
www.cinevate.com
Dennis Wood is offline   Reply With Quote
Old February 14th, 2010, 09:25 PM   #9
New Boot
 
Join Date: Feb 2010
Location: New York, NY
Posts: 17
Quote:
Originally Posted by Ted Ramasola View Post
I have tested my DIY gearless ff on my 80-200 zoom ring instead of the focus ring. It will give a smooth turn BUT the problem is most zooms arent parafocal.

Usually, we "traditionally" zoom in focus, and zoom out. And know that focus stays. This is not the case with still camera lenses.

Heres my ff.

DIY Gearless Follow Focus Test
I am a complete newbie trying to learn some stuff about the DSLR video features. So there are no lenses that would allow for having a subject consistently in focus?

I'm thinking more along the lines of sports.
Sean Feiertag is offline   Reply With Quote
Old February 14th, 2010, 09:57 PM   #10
Regular Crew
 
Join Date: Nov 2008
Location: Oakland, CA
Posts: 112
Very expensive cinema lenses (think $10k on the low end).
Graham King is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

B&H Photo Video
(866) 521-7381
New York, NY USA

Scan Computers Int. Ltd.
+44 0871-472-4747
Bolton, Lancashire UK


DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Canon EOS / MXF / AVCHD / HDV / DV Camera Systems > Canon EOS Crop Sensor for HD


 



All times are GMT -6. The time now is 07:36 AM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network