Jump to content
Sign in to follow this  
Jared Williams

Film Latitude/Dynamic Range

Recommended Posts

Hello all,

 

This is my first post. I'm a student and have mainly shot digital and last week finished my first project on 16. It was stocks 7219 and 7205. I should be getting footage back by the end of the week. It was transferred best light to HDCAM.

 

A question I have deals with the film handling overexposure. With the HVX or EX-1 I have found myself really having a issue with clipping in EXT. shots where there is a wide spectrum of shadows and highlights and something 2 stops over can clip.

 

I found myself in a regular situation (no ultrabounce or HMI's) where I had a shot that was backlit and a exposure difference. Through some help from these forums I underexposed a bit but my background was 2 stops over. I have done the same with digital and always find myself clipping and needing to adjust the shot a lot in post to make it right. With film will I find 2 stops to be too much? Should I have underexposed more? I was a stop in a half under (with incident) in the shadows. Before shooting I remember my teacher saying film likes the highlights and digital sees in the shadows.

 

So I am just hoping to get a decent image that with some slight tweaking I will be happy.

 

Also what is the difference between Latitude/Dynamic range? One I hear a stock has 7 stops latitude then I heard 16 stops dynamic range. So I am a little confused.

Share this post


Link to post
Share on other sites

Either way, you have at least another two to three stops of overexposure detail with color negative over digital. Digital has almost no latitude for overexposure -- even a two-stop overexposure is hard to correct back down to normal.

 

The confusion over naming a range is that there is a difference between total measurable range and a workable, practical range that takes into account that a film print or video display generally has to use a smaller range than the original. Plus many ways of measuring dynamic range count detail recorded in the extreme low end which is usually too noisy or grainy to be usable detail.

 

So while I can tell you that the general idea is that the best digital cameras have something like 11 to 12 stops of dynamic range and film negative has something like 15-stops of dynamic range, you generally won't find that much range to be usable in your work, you have to count on a narrower range. For most digital cameras, it's more like an 8 to 10-stop range max and for film it's more like a 10 to 12-stop range.

 

Generally "latitude" means the range that is correctable, the degree to which one can correct an image, while "dynamic range" refers to the total range of exposure values that are recorded. So latitude is a much smaller range than dynamic range. For example, you can record detail that is five-stops underexposed on both film and digital, but that doesn't mean that a shot that is five-stops underexposed is correctable back to normal.

Share this post


Link to post
Share on other sites
Also what is the difference between Latitude/Dynamic range? One I hear a stock has 7 stops latitude then I heard 16 stops dynamic range. So I am a little confused.

 

The dynamic range is the distance in stops from the toe of the curve to the shoulder. It is a measurement of the usable range of the curves. In the case of 7219 the range is 15 stops. That is the difference between your minimum exposure for shadows and maximum exposure for highlights.

Latitude is a measurement of how much you can overexpose from the minimum exposure that will record your shadows without crushing, to an exposure that will record your highlights without crushing. The latitude is entirely dependent on the brightness range of your scene and the dynamic range of the film. If you are shooting a gray card in a fog you will have a very low brightness range say 1 stop. In this case the latitude of the film would be 14 stops. If you are shooting a scene with a high brightness range, a polar bear in a coal cellar and the difference between the highlights and the shadows is 6 stops then the latitude of the film is only 9 stops.

Brian

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  


  • Metropolis Post



    G-Force Grips



    The Original Slider



    Glidecam



    Broadcast Solutions Inc



    Visual Products



    Gamma Ray Digital Inc



    Wooden Camera



    Tai Audio



    New Pro Video - New and Used Equipment



    Abel Cine



    CineLab



    Ritter Battery



    Serious Gear



    FJS International



    Paralinx LLC



    Just Cinema Gear



    Rig Wheels Passport



    Media Blackout - Custom Cables and AKS


    Cinematography Books and Gear
×
×
  • Create New...