Is there a way to fix the darker image caused by zooming? at DVinfo.net

Ed Glaser · May 31st, 2006, 11:13 AM

I have what is probably a very standard question, but I'm afraid I couldn't seem to find an answer seaching through the forums. Oh, and my apologies if this is posted in the wrong forum.

I know that by zooming in with a videocamera, the amount of light intake is reduced, and the image gets progressively darker. But is there any way around this?

I use a Panasonic AG-DVC30. My old camera was a consumer Handicam, and it seemed to deal with the problem automatically, so I would zoom in and the light level would look the same. Similarly, more professional videos use zooms all the time and it looks fine, so there must be a way around it. I can't imagine professional shoots have an "exposure puller" as well as a focus puller... But then, I really don't know.

However, not being able to zoom is driving me nuts.

Raji Barbir · May 31st, 2006, 11:21 AM

does the DVC30 have an automatic gain setting? You might have it set to manual, so it stays the same while the aperture gets smaller (ie. bigger number). I imagine that's what handheld cameras do to keep the video looking like it's lit the same. Also, you might try setting your camera to aperture priority so that it automatically adjusts the shutter speed.

Boyd Ostroff · May 31st, 2006, 11:26 AM

This should only be an issue when shooting in dark places where you need the maximum aperture. For example, let's say the largest aperture at full wide is f1.6 and at full telephoto it goes down to f2.8. If you set the iris at 1.6 and zoom in then you'll get the problem you described - things will get darker (assuming you're in full manual mode).

On the other hand, if you set the iris to f2.8 at the wide end of the zoom, then there won't be any change as you zoom in. But if you're working in a dark place then this might not work for you so you could try one of Raji's suggestions.

Ed Glaser · May 31st, 2006, 12:03 PM

You're right -- I think the problem occurs in low-light environments. Unfortunately, I'm doing a great deal of shooting in low-light.

I'll have to check on the automatic gain. From what I gather, changing the shutter speed isn't the greatest idea. Especially since I ultimately want to run the footage through Magic Bullet. So I've been keeping it at 1/60.

May 31st, 2006, 11:13 AM	#1
Ed Glaser New Boot Join Date: Jan 2006 Posts: 21	Is there a way to fix the darker image caused by zooming? I have what is probably a very standard question, but I'm afraid I couldn't seem to find an answer seaching through the forums. Oh, and my apologies if this is posted in the wrong forum. I know that by zooming in with a videocamera, the amount of light intake is reduced, and the image gets progressively darker. But is there any way around this? I use a Panasonic AG-DVC30. My old camera was a consumer Handicam, and it seemed to deal with the problem automatically, so I would zoom in and the light level would look the same. Similarly, more professional videos use zooms all the time and it looks fine, so there must be a way around it. I can't imagine professional shoots have an "exposure puller" as well as a focus puller... But then, I really don't know. However, not being able to zoom is driving me nuts.

May 31st, 2006, 11:21 AM	#2
Raji Barbir Regular Crew Join Date: Dec 2005 Location: Salt Lake City, UT Posts: 97	does the DVC30 have an automatic gain setting? You might have it set to manual, so it stays the same while the aperture gets smaller (ie. bigger number). I imagine that's what handheld cameras do to keep the video looking like it's lit the same. Also, you might try setting your camera to aperture priority so that it automatically adjusts the shutter speed.

May 31st, 2006, 11:26 AM	#3
Boyd Ostroff Wrangler Join Date: Dec 2002 Location: Mays Landing, NJ Posts: 11,802	This should only be an issue when shooting in dark places where you need the maximum aperture. For example, let's say the largest aperture at full wide is f1.6 and at full telephoto it goes down to f2.8. If you set the iris at 1.6 and zoom in then you'll get the problem you described - things will get darker (assuming you're in full manual mode). On the other hand, if you set the iris to f2.8 at the wide end of the zoom, then there won't be any change as you zoom in. But if you're working in a dark place then this might not work for you so you could try one of Raji's suggestions.

May 31st, 2006, 12:03 PM	#4
Ed Glaser New Boot Join Date: Jan 2006 Posts: 21	You're right -- I think the problem occurs in low-light environments. Unfortunately, I'm doing a great deal of shooting in low-light. I'll have to check on the automatic gain. From what I gather, changing the shutter speed isn't the greatest idea. Especially since I ultimately want to run the footage through Magic Bullet. So I've been keeping it at 1/60.