Cinematography Mailing List - CML
    advanced

Hello, I just completed a series of spots where we did the old rear-net..Fogal brand this time. We used standard primes, swing-shifts and had to pull my 10:1 out for one shot. The 1st was a bit concerned about the travel of the rear elements on my Cooke/Century Series 2000 primes [worried that the extra travel might make a mess in my 35-3 camera cavity], but we had no problems. But, the zoom was a new one on me, I had never had a situation before where we rear netted a zoom...and this particular shot called for a massive zoom...from a 250mm tight all the way out to a 32mm..... The 1st was VERY concerned that this zoom out would make the net effect compress more making it more defocused the longer the focal length went...but my thought was that since we were on the rear element, as opposed to a front mount filter, that we would not change the effectiveness of the net regardless of the focal length. Through the camera, the effect looked great...and talking to the color timer, the effect is fine...but since I haven't seen the results yet myself, I always hold a bit of concern. Does anyone have any experiences rear-neting a zoom and what were their thoughts on the results?

Cheers, Jeff Barklage, s.o.c.

US based DP

http://www.barklage.com


Jeff, I did this back in the late 80s and early 90s quite a few times. Mostly 10-1 zooms, like the Cooke or the Angenieux HR or the 11-1 Primo.

In my memory, which is a bit foggy, we shot all over the lens, from 25mm to 250mm and never had any matching problems. I rarely, maybe never, zoomed over the range of the lens in one shot, but I shot many dialogue spots where I'm sure I used the lens all over the range. There's still one on my reel, I'm slightly embarrassed to admit . . .

-- Jim Dollarhide

Director of Photography


I've used all sorts of nets BTL on primes and zooms. I've never really had a problem. I also didn't shoot with a stop more than T/4-5.6 either. I know the longer lenses with more of a T/stop will have enough depth of field to allow one to see the net's texture.

Mark Woods,

Director of Photography

Stills That Move, Pasadena, CA

http://www.markwoods.com/


>I know the longer lenses with more of a T/stop will have enough depth of field to >allow one to see the net's texture.

Seems like that would be the "shorter" lenses ?

Jim

-- Jim Dollarhide

Director of Photography


> Seems like that would be the "shorter" lenses ?

No, the depth of field is just the opposite on the other side of the lens. On wide lenses, or short lenses, the rear depth of field is very shallow. On the longer lenses it's much greater.

Mark Woods,

Director of Photography


Mark Woods wrote :

>On wide lenses, or short lenses, the rear depth of field

It's called "depth of focus" when behind the lens, "depth of field" in front of the lens.

Jeff "semantics cop" Kreines


Busted! But accurate.

Mark Woods, Director of Photography


 


Copyright © CML. All rights reserved.