Zooming when moving... at DVinfo.net

Scott Welch · April 27th, 2007, 12:33 PM

When I move when zooming in it seems to stop the zooming til I stop moving and then it'll work fine... Anyone know why?

Jack Barker · April 28th, 2007, 09:00 AM

Is Image Stabilizer turned on while you are doing this? If so, try turning it off.

Mike Teutsch · April 28th, 2007, 09:12 AM

Quote:

Originally Posted by Scott Welch

When I move when zooming in it seems to stop the zooming til I stop moving and then it'll work fine... Anyone know why?

Zoom and focus are both controlled by the same motor, if your are moving then that camera is having to focus. Make a choice.

Mike

Eric Shepherd · April 28th, 2007, 04:34 PM

Would this also be a problem in manual mode, using the zoom with the motor, while focusing by hand, since the focus is servo controlled?

What is the point of the full manual lens, btw? I've used studio and handheld high-end cameras, but never needed to look at the numbers, but the numbers seem to be a big selling point? :) i could see having a quicker response than the servos provide. But what's the big deal? :)

-Eric

Owen Hughes · April 28th, 2007, 04:59 PM

Yes, you cannot manually adjust the focus whilst zooming in using the servo. It's a bit annoying, but like somebody else has said, you need to make a choice on which is more important

Jack Barker · April 28th, 2007, 05:46 PM

You know guys, the OP never even mentioned focusing in his question. He's having trouble zooming while he's moving.

Eric Shepherd · April 28th, 2007, 06:03 PM

we're having trouble focusing on the question ;)

So then is the problem that the motor isn't running/moving the lens while being shaken from movement? sounds like a wiring or mechanical connection problem to me.

Chris Hurd · April 28th, 2007, 08:59 PM

Quote:

Originally Posted by Scott Welch

When I move when zooming in it seems to stop the zooming til I stop moving...

Define "moving." What do you mean by that?

Mike Teutsch · April 29th, 2007, 09:12 AM

Quote:

Originally Posted by Jack Barker

You know guys, the OP never even mentioned focusing in his question. He's having trouble zooming while he's moving.

To clarify this: "Moving"

Unless he is moving in a circle around his subject and is maintaining exact distance and aiming at the same spot, then the distance to the subject will change and the camera will attempt to focus. The camera's auto focus does not care whether you move 1 foot or 10 feet away or closer, it will try to maintain perfect focus, and this is irregardless of your depth of field.

To foil this auto system you might try this:

Close down the iris as much as possible and increase shutter speed to maintain the look you want. This will give you a great deal of depth-of-field, then turn auto-focus off. That might work.

Otherwise, the motor simply can't do both at the same time. This is also true if you turn off auto-focus and use the focus ring, or zoom by hand, because the zoom and focus rings are not really manual as you are only actuating the motor by turning them by hand.

A Canon 16x manual lens would work if you are good at maintaining focus, as the focus ring is true manual and the zoom can be operated by servo or manually.

Good Luck----Mike

Jack Barker · April 29th, 2007, 09:58 AM

Mike, the OP not only didn't mention focus, he didn't mention auto focus. What the heck are you talking about?

Mike Teutsch · April 29th, 2007, 10:30 AM

Quote:

Originally Posted by Jack Barker

Mike, the OP not only didn't mention focus, he didn't mention auto focus. What the heck are you talking about?

I'm saying that when he moves the auto-focus has to refocus and that there is only one motor that does both jobs. So when the motor is trying to focus, it has to stop zooming.

Mike

Greg Boston · April 29th, 2007, 10:48 AM

Quote:

Originally Posted by Jack Barker

Mike, the OP not only didn't mention focus, he didn't mention auto focus. What the heck are you talking about?

Jack, there is an assumption being made here by Mike (and myself after reading the OP), that auto-focus is turned on. If that's the case, and the camera operator is moving, the auto-focus is attempting to maintain optimal focus and is therefore 'using' the only available motor shared by zoom and focus. When he stops moving, the auto-focus can release the motor for use by the zoom ring.

I know the original poster said nothing about focusing. But given the operational restriction of the lens, and the description of the problem, it is a fairly safe assumption that auto-focus was on at the time.

-gb-

April 27th, 2007, 12:33 PM	#1
Scott Welch Regular Crew Join Date: Jun 2006 Location: Wisconsin Posts: 27	Zooming when moving... When I move when zooming in it seems to stop the zooming til I stop moving and then it'll work fine... Anyone know why?

April 28th, 2007, 09:00 AM	#2
Jack Barker Major Player Join Date: Apr 2004 Location: Ann Arbor, MI Posts: 342	Is Image Stabilizer turned on while you are doing this? If so, try turning it off.

April 28th, 2007, 04:34 PM	#4
Eric Shepherd Major Player Join Date: Feb 2007 Location: Orlando, FL Posts: 404	Would this also be a problem in manual mode, using the zoom with the motor, while focusing by hand, since the focus is servo controlled? What is the point of the full manual lens, btw? I've used studio and handheld high-end cameras, but never needed to look at the numbers, but the numbers seem to be a big selling point? :) i could see having a quicker response than the servos provide. But what's the big deal? :) -Eric

April 28th, 2007, 04:59 PM	#5
Owen Hughes Regular Crew Join Date: Feb 2005 Location: Cwmbran, Wales, UK Posts: 41	Yes, you cannot manually adjust the focus whilst zooming in using the servo. It's a bit annoying, but like somebody else has said, you need to make a choice on which is more important

April 28th, 2007, 05:46 PM	#6
Jack Barker Major Player Join Date: Apr 2004 Location: Ann Arbor, MI Posts: 342	You know guys, the OP never even mentioned focusing in his question. He's having trouble zooming while he's moving.

April 28th, 2007, 06:03 PM	#7
Eric Shepherd Major Player Join Date: Feb 2007 Location: Orlando, FL Posts: 404	we're having trouble focusing on the question ;) So then is the problem that the motor isn't running/moving the lens while being shaken from movement? sounds like a wiring or mechanical connection problem to me.

April 29th, 2007, 09:58 AM	#10
Jack Barker Major Player Join Date: Apr 2004 Location: Ann Arbor, MI Posts: 342	Mike, the OP not only didn't mention focus, he didn't mention auto focus. What the heck are you talking about?