Nikkor Zooms for Video: OK...I will acknowledge that I've proudly said in the past that I had little or no interest in the video capabilities of my DSLR cameras. I have been...

larryepage Loc: North Texas area

OK...I will acknowledge that I've proudly said in the past that I had little or no interest in the video capabilities of my DSLR cameras. I have been experimenting with the capabilities of some of my newer equipment, however, and have discovered some interesting and a little bit troubling things. Not so much about the cameras, but about the lenses.

My preference for still photography is to use good, low ratio, constant aperture zooms...generally no more than 3:1 or so. I find that those tend to give real-world performance that is pretty similar to most prime lenses on today's cameras.

The problem, though, is that video places different requirements on lenses. Specifically, wider zoom ranges are needed, and, more importantly, a lens used for video must maintain focus as its focal length is changed, because 'live zooming' is a key technique to creating interesting video. (And because a very common technique in videography is to 'zoom out' to maximum focal length for most accurate focusing, then zoom back out to the shooting fl.)

A couple of weeks ago, I was videoing a robotics match using my 18-200mm DX Nikkor zoom, since it is the only wide ratio zoom that I own. It performed reasonably well in many aspects, but very poorly at maintaining focus while zooming.

So my question for the forum is whether anyone has discovered and used lenses on Nikon cameras, whether DX or FX, with a zoom ratio of 10:1 or more, which maintain focus while zooming. My question is not what specifications say, or what reviews have indicated, but rather what your actual experience has been.

I am expecting that focus maintenance has not been a design priority at Nikon. The shoulder-carried Panasonic VHS camcorder that I bought 30 years or so ago maintained focus very well throughout its zoom range. And as a side note, I'm wondering if this is something that Canon does better at, and is the reason that Canon DSLRs have been used in the filming of several movies. (And no, I'm not going to switch, even if that turns out to be the case. If anything, I'd just get a dedicated video camera.)

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

larryepage wrote:

OK...I will acknowledge that I've proudly said in the past that I had little or no interest in the video capabilities of my DSLR cameras. I have been experimenting with the capabilities of some of my newer equipment, however, and have discovered some interesting and a little bit troubling things. Not so much about the cameras, but about the lenses.

My preference for still photography is to use good, low ratio, constant aperture zooms...generally no more than 3:1 or so. I find that those tend to give real-world performance that is pretty similar to most prime lenses on today's cameras.

The problem, though, is that video places different requirements on lenses. Specifically, wider zoom ranges are needed, and, more importantly, a lens used for video must maintain focus as its focal length is changed, because 'live zooming' is a key technique to creating interesting video. (And because a very common technique in videography is to 'zoom out' to maximum focal length for most accurate focusing, then zoom back out to the shooting fl.)

A couple of weeks ago, I was videoing a robotics match using my 18-200mm DX Nikkor zoom, since it is the only wide ratio zoom that I own. It performed reasonably well in many aspects, but very poorly at maintaining focus while zooming.

So my question for the forum is whether anyone has discovered and used lenses on Nikon cameras, whether DX or FX, with a zoom ratio of 10:1 or more, which maintain focus while zooming. My question is not what specifications say, or what reviews have indicated, but rather what your actual experience has been.

I am expecting that focus maintenance has not been a design priority at Nikon. The shoulder-carried Panasonic VHS camcorder that I bought 30 years or so ago maintained focus very well throughout its zoom range. And as a side note, I'm wondering if this is something that Canon does better at, and is the reason that Canon DSLRs have been used in the filming of several movies. (And no, I'm not going to switch, even if that turns out to be the case. If anything, I'd just get a dedicated video camera.)

OK...I will acknowledge that I've proudly said in ... (show quote)

TriX Loc: Raleigh, NC

Or alternately, you could just use a video camera. I have tried videos with my Canon DSLR, and the focusing problems you describe while zooming are a real PIA.

larryepage Loc: North Texas area

Thanks guys. I really suspected that was going to be the answer. Of course, I don't think I necessarily have to have a perfectly parfocal lens...just one that is a better approximation than what I have now. Or at least a firmware update that will allow continuous autofocus when shooting video...

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

larryepage wrote:

Thanks guys. I really suspected that was going to be the answer. Of course, I don't think I necessarily have to have a perfectly parfocal lens...just one that is a better approximation than what I have now. Or at least a firmware update that will allow continuous autofocus when shooting video...

That would be great - but unlikely at least for now.