Jump to content


Photo

More grain with wider lens???


  • Please log in to reply
3 replies to this topic

#1 Frank Barrera

Frank Barrera
  • Sustaining Members
  • 464 posts
  • Cinematographer
  • Los Angeles, CA

Posted 02 November 2006 - 06:04 PM

just saw the dailies from a 16MM spec spot we did last week. we used an Arri SR3 with a set of Zeiss 35MM primes. My first time using 35MM lenses on 16 camera. I attempted to over expose everything by 1/2 stop to "tighten" the grain a bit. Everything looks good, smooth and sharp but all the 10MM material appears to have more grain in the midtones than the longer lenses. It's very noticable and noisey. The 10MM was the widest lens I used. The lab checked the neg and it's not under exposed. But the grain sort of looks like it was under. It's a bit disappointing really.

Question: Is this a result of the 10MM lens? Does it being a 35MM format lens rather than a 16MM format lens have any effect???

I'm scratching me head over here...

thanks

f
  • 0

#2 Bernhard Zitz

Bernhard Zitz
  • Basic Members
  • PipPipPipPip
  • 342 posts
  • Other
  • Z├╝rich, Switzerland

Posted 02 November 2006 - 07:28 PM

hmm, might be a purely subjective phenomena. I always felt that the stuff I shot with 10mm looked grainier and softer than the what I did with a 75mm, but when I analyzed the still pictures; grain and sharpness looked the same. I have the same sensation in video(with my DVX-100). I hate this shots at the wide end of the lens, it feels soft and even at 0dB you notice the video-grain...

it seems that pictures shot with a longer lens tend to mislead the eye in a way that you notice less "failures" like grain etc... but this might be as well a purely subjective opinion of my own...

The lens shouldn't affect the grain, if you exposed the same way like the rest there shouldn't be any difference in grain...

I'd analyze the shots as still pictures, zoom in on a shot with a longer lens and do the same thing with a 10mm shot, then put one a side another and look if there really is a difference in grain...

cheers, bernhard
  • 0

#3 Bernie O'Doherty

Bernie O'Doherty
  • Sustaining Members
  • 232 posts
  • Other
  • Newark Valley, NY

Posted 03 November 2006 - 08:17 AM

Hi, Frank,

I'd like to add a couple of thoughts. Wide lens design is much more difficult than normal perspective lenses. The problem is that you're trying to squeeze much more information onto the film frame. We're taking both sides to the max, as well as top and bottom. That's a lot of complex lens design. I can't imagine the necessary formulae! I've spoken to lens designers at Panavision over the years, and they say that to design a perfect wide lens would almost be economically unfeasible--they can get very close, but generally something misses the mark. Holding perfect definition over the total area suffers. Contrast suffers. Flare becomes more of a problem. The rear exit pupil disperses light over a wider area and can cause internal reflections in the camera, etc.

Another aspect is finding focus. As you know, it's much more difficult to "hit" your focus point because of the depth of focus and our eyes' difficulty in distinguishing 7 ft from 8 ft, for example. This slight shift may be seen as grain to our eyes. Adding all of the negatives mentioned above might translate to a grainier look when compared with "normal "lenses.

I find that I need to check wide lenses with running film all the time. The normal film-in-motion pullback is greatly emphasized when using anything wider than 35mm in 35 format or 12mm in 16mm.

So, to summarize a long-winded post, I think there's just a difference in the look of wide lenses because of their inherent envelope-pushing design; I don't think the problem is anything you've done. Just make sure your focus is right on with these wider lenses by having it checked with moving film (important) on a collimator. Hope this helps a little!

Cheers,

Bernie.
  • 0

#4 Frank Barrera

Frank Barrera
  • Sustaining Members
  • 464 posts
  • Cinematographer
  • Los Angeles, CA

Posted 03 November 2006 - 08:52 AM

I suppose the answer may be that I need to shoot some tests using the Zone system so I can see where the grain becomes more or less apparent on which lenses. This would be my point of reference. Until then we'll just utilize some grain reduction on those particular shots.

Thanks

F
  • 0


The Slider

Rig Wheels Passport

Abel Cine

Media Blackout - Custom Cables and AKS

Paralinx LLC

Glidecam

CineTape

Opal

Aerial Filmworks

Willys Widgets

Broadcast Solutions Inc

Gamma Ray Digital Inc

Ritter Battery

Technodolly

Metropolis Post

Visual Products

FJS International, LLC

Wooden Camera

Tai Audio

rebotnix Technologies

CineLab

CineTape

Ritter Battery

Metropolis Post

Glidecam

Abel Cine

Wooden Camera

Rig Wheels Passport

Aerial Filmworks

Technodolly

Broadcast Solutions Inc

FJS International, LLC

Media Blackout - Custom Cables and AKS

Opal

CineLab

Visual Products

The Slider

Tai Audio

Willys Widgets

rebotnix Technologies

Paralinx LLC

Gamma Ray Digital Inc