Difference between still and video lenses? at DVinfo.net

Patrick Janka · November 27th, 2010, 08:09 PM

I apologize in advance if this has been covered, but should lens selection be based on whether one is shooting stills or video, or can the same set of lenses work equally for both? Thanks!

Lee Ying · November 28th, 2010, 09:19 AM

From my perspective, since there is no flashlight in video, the speed of the lens is probably more important than the absolute sharpness as all lenses are trade-offs of various features. The second thing I think its important is the focus ring--whether it is smooth or rotates in the direction you want. You probably don't want to have a set of lenses that have different focus ring directions.

Norman Pogson · November 28th, 2010, 02:28 PM

Yes the same set of lenses can be used for still or video.

John Wiley · November 28th, 2010, 05:37 PM

Any stills lens is going to be a compromise for video because that is not what it was primarily designed for.

Having said that, some lenses are (by chance/luck/design) better for video than other still lenses. Here's a few important considerations:

1) Constant aperture - some zoom lenses have the same maximum aperture no matter what the focal length, whereas others will have a smaller maximum aperture at full zoom. Constant aperture lenses let you zoom in/out without having to adjust exposure mid shot which can be very obvious on DSLR's which aren't designed with the same stepless smooth adjustments as most camcorders.

2) Focus ring - some lenses are designed entirely for autofocus and have terrible focus rings which are difficult to grip or rotate. I've even seen some cheaper Canon lenses that don't have a focus ring at all. Obviously this will be a problem for video because you need manual focus.

3) Parfocal/varifocal - most camcorder lenses are parfocal, meaning that focus distance stays the same regardless of zoom. This allows you to zoom in fully, focus, then zoom and to frame your shot, knowing you can zoom in or out at any time without ruining your perfect focus. Most still zoom lenses are varifocal, meaning that when the zoom changes, so too does the focus distance. So zooming midway through a shot becomes very difficult or impossible.

Norman Pogson · November 29th, 2010, 07:00 AM

In reality I do not zoom in or out with a dslr while shooting video, that is a camcorder shot. I have some parfocal zooms, but I don't need to zoom in to focus then zoom out to frame the shot, as my Canon 7D has a x5 and x10 magnifier of the rear LCD image that does that for me, or use an external monitor like Marshall that has focus assist.

November 27th, 2010, 08:09 PM	#1
Patrick Janka Major Player Join Date: Jan 2010 Location: Orlando, FL Posts: 623	Difference between still and video lenses? I apologize in advance if this has been covered, but should lens selection be based on whether one is shooting stills or video, or can the same set of lenses work equally for both? Thanks!

November 28th, 2010, 02:28 PM	#3
Norman Pogson Regular Crew Join Date: Feb 2010 Location: Ottawa, Canada Posts: 140	Yes the same set of lenses can be used for still or video. __________________ My Stock Video Blog Linkedin

November 29th, 2010, 07:00 AM	#5
Norman Pogson Regular Crew Join Date: Feb 2010 Location: Ottawa, Canada Posts: 140	In reality I do not zoom in or out with a dslr while shooting video, that is a camcorder shot. I have some parfocal zooms, but I don't need to zoom in to focus then zoom out to frame the shot, as my Canon 7D has a x5 and x10 magnifier of the rear LCD image that does that for me, or use an external monitor like Marshall that has focus assist. __________________ My Stock Video Blog Linkedin

November 28th, 2010, 09:19 AM	#2
Lee Ying Regular Crew Join Date: Feb 2007 Location: Atlanta, Ga Posts: 73	From my perspective, since there is no flashlight in video, the speed of the lens is probably more important than the absolute sharpness as all lenses are trade-offs of various features. The second thing I think its important is the focus ring--whether it is smooth or rotates in the direction you want. You probably don't want to have a set of lenses that have different focus ring directions.

November 28th, 2010, 05:37 PM	#4
John Wiley Trustee Join Date: Oct 2008 Location: Byron Bay, Australia Posts: 1,155	Any stills lens is going to be a compromise for video because that is not what it was primarily designed for. Having said that, some lenses are (by chance/luck/design) better for video than other still lenses. Here's a few important considerations: 1) Constant aperture - some zoom lenses have the same maximum aperture no matter what the focal length, whereas others will have a smaller maximum aperture at full zoom. Constant aperture lenses let you zoom in/out without having to adjust exposure mid shot which can be very obvious on DSLR's which aren't designed with the same stepless smooth adjustments as most camcorders. 2) Focus ring - some lenses are designed entirely for autofocus and have terrible focus rings which are difficult to grip or rotate. I've even seen some cheaper Canon lenses that don't have a focus ring at all. Obviously this will be a problem for video because you need manual focus. 3) Parfocal/varifocal - most camcorder lenses are parfocal, meaning that focus distance stays the same regardless of zoom. This allows you to zoom in fully, focus, then zoom and to frame your shot, knowing you can zoom in or out at any time without ruining your perfect focus. Most still zoom lenses are varifocal, meaning that when the zoom changes, so too does the focus distance. So zooming midway through a shot becomes very difficult or impossible.