XL2 goes soft in Tv and Av mode. at DVinfo.net

Jeff Carrion · September 23rd, 2005, 10:43 AM

So I've been playing around with my new XL2 and I found that when shooting in Tv and Av there are only a limited number of stops and shutter speeds to choose from as opposed to the XL1. So first of all, why the heck does the XL2 only offer its full range of settings in Manual mode?
Secondly, when I'm in Tv mode at 1/60 shooting in bright sunlight, the lens will stop down to like F32 and the whole picture will go really soft, REALLY soft. So then I must turn on some ND to open the lens some more. Is this a normal deal when the lens is stopped down so tight? (BTW, I'm using the 16x manual lens)
I also had a strange situation in sunlight when the lens seemed to go beyond F32 and almost close completely when shooting in Auto and panning around front-lit and back-lit objects. The picture would go soft and dark and strobe in and out contrast in a very erratic way. Anyone else seen this?

Chris Hurd · September 23rd, 2005, 11:04 AM

Quote:

Originally Posted by Jeff Carrion

...when I'm in Tv mode at 1/60 shooting in bright sunlight, the lens will stop down to like F32 and the whole picture will go really soft, REALLY soft.

This is a common issue in videography as well as photography. It's called diffraction and is explained here:

http://www.dvinfo.net/canon/articles/article19.php

The solution is to either not go beyond f/16 and/or add ND.

Greg Boston · September 23rd, 2005, 11:08 AM

Jeff,

High F-stop settings will induce a softness to the image. Lenses have a 'sweet spot' where the image is at its best. Typically, around 2 or 3 stops away from max open aperture. This is just a rule of thumb.

A couple things you can do are to set the gain at -3db and of course, use both ND filters. To keep the iris open far enough to keep the image sharp, you will likely have to go with a higher shutter speed or add additional ND filters in front of the lens.

-gb-

Ash Greyson · September 23rd, 2005, 11:16 AM

I guess I am confused... why would you NOT want an ND filter if you were having to close the aperture so much? Aperture is for FINE ADJUSTMENTS, not ultimate control. When you use the aperture to control the light, you not only get softness but you lose depth of field.

ash =o)

September 23rd, 2005, 10:43 AM	#1
Jeff Carrion New Boot Join Date: Aug 2005 Location: Chicago, IL Posts: 19	XL2 goes soft in Tv and Av mode. So I've been playing around with my new XL2 and I found that when shooting in Tv and Av there are only a limited number of stops and shutter speeds to choose from as opposed to the XL1. So first of all, why the heck does the XL2 only offer its full range of settings in Manual mode? Secondly, when I'm in Tv mode at 1/60 shooting in bright sunlight, the lens will stop down to like F32 and the whole picture will go really soft, REALLY soft. So then I must turn on some ND to open the lens some more. Is this a normal deal when the lens is stopped down so tight? (BTW, I'm using the 16x manual lens) I also had a strange situation in sunlight when the lens seemed to go beyond F32 and almost close completely when shooting in Auto and panning around front-lit and back-lit objects. The picture would go soft and dark and strobe in and out contrast in a very erratic way. Anyone else seen this? __________________ Jeff Carrion Director/Editor Midwest Outdoors Television "TV said that? Then it must be true." -Homer Simpson

September 23rd, 2005, 11:08 AM	#3
Greg Boston Wrangler Join Date: Oct 2003 Location: DFW area, TX Posts: 6,117 Images: 1	Jeff, High F-stop settings will induce a softness to the image. Lenses have a 'sweet spot' where the image is at its best. Typically, around 2 or 3 stops away from max open aperture. This is just a rule of thumb. A couple things you can do are to set the gain at -3db and of course, use both ND filters. To keep the iris open far enough to keep the image sharp, you will likely have to go with a higher shutter speed or add additional ND filters in front of the lens. -gb-

September 23rd, 2005, 11:16 AM	#4
Ash Greyson Trustee Join Date: May 2003 Location: Tulsa, OK Posts: 1,689	I guess I am confused... why would you NOT want an ND filter if you were having to close the aperture so much? Aperture is for FINE ADJUSTMENTS, not ultimate control. When you use the aperture to control the light, you not only get softness but you lose depth of field. ash =o)