Let's Talk Depth Of Field

[Erick Stoll]

I'm looking to shoot a short film on the Red with Zeiss standard primes, utilizing wide lenses the most. It is, obviously, a budget film, so pumping ridiculous amounts of light in to increase our DOF isn't going to be an option, and we will probably be sitting around 2.8-5.6, at 320 of course.

What is our DOF going to be? I want shallow DOF in general for this film, but I don't want to be limited in anything. Just how ridiculous is 35mm DOF with the Red?

 

[Colin Sheldon]

There are DOF calculators that you can use to figure it out. isee4k is a great iphone app.

25mm+T2.8+Focused at 10 feet = everything from 7.5feet to 15.1 feet will be in focus.

 

[Brandon Fraley]

if you're going to be using 25mm and wider, it's going to be difficult to get shallow focus on anything that's farther away than 4-5 feet.

Best thing to do it spend a few minutes testing, you'll get the feel very quickly.

 

[Daniel Browning]

What is our DOF going to be?

It depends greatly on your display conditions. A 4K projection seen by viewers sitting close enough and with high enough acuity will see much thinner DOF than direct-to-DVD seen from across the room by a near-sighted viewer.

 

[Brandon Fraley]

It depends greatly on your display conditions. A 4K projection seen by viewers sitting close enough and with high enough acuity will see much thinner DOF than direct-to-DVD seen from across the room by a near-sighted viewer.

very true, If you're going to project it on a large screen in 4k, it will be more apparent, but if ur going to dvd, those wide lenses will keep everything in focus from 4 feet to infinity.

 

[David Mullen ASC]

Saying you want the depth of field to be shallow but not too shallow is a bit like saying you want your food to be salty but not too salty -- it's hard to quantify it.

F/2.8 is a commonly-used f-stop for interior work, so if you shoot 4K at that stop, you'll be in the same DOF characteristics as most features shot in 35mm -- the main challenge will be following-focus on tighter shots of moving actors. Whether that's "too shallow" all depends on how hard your shots are going to be to follow-focus and how good your focus puller is. And, as mentioned already, how large the final image is going to be.

 

[Erick Stoll]

Saying you want the depth of field to be shallow but not too shallow is a bit like saying you want your food to be salty but not too salty -- it's hard to quantify it.

F/2.8 is a commonly-used f-stop for interior work, so if you shoot 4K at that stop, you'll be in the same DOF characteristics as most features shot in 35mm -- the main challenge will be following-focus on tighter shots of moving actors. Whether that's "too shallow" all depends on how hard your shots are going to be to follow-focus and how good your focus puller is. And, as mentioned already, how large the final image is going to be.

Excuse my lack of clarity. I really just meant that I'd like to shoot with a shallow DOF, with the option of getting deeper if need be. Also, I've read about instances where you just have a few millimeters worth of focus... which just sounds ghastly to deal with.

Also, I'm confused as to why what you are viewing it on would actually change the DOF. I understand that it could affect the viewers perception, but to actually change the DOF?

 

[David Mullen ASC]

Well, yes and no, DOF charts are based around the Circle of Confusion figure, which to some degree is based on degree of enlargement. But of course, you could blow up a picture to fill a 100' wide screen but if someone watches it from the back row, it might as well be a TV screen at home.

But I'm talking more generally, that focus mistakes are easier to catch on a large screen.

A few millimeters of depth of field seems limiting, but again, there are other factors that affect how visible that is. Until you start shooting, you'll never know whether it is a problem or not. Obviously there are hundreds of people shooting everyday with 35mm depth of field, big and small budget shows, and they manage to deal with it. So don't let a DOF chart scare you off from trying something new.

 

[PatC]

Hey Erick,

I am no master, but I think that you should wait and get more $$$ so you can get the lighting you need for the look you want. Don't sell yourself short because you need to shoot right now. I think that having a narrow DOF is the cat's meow, See if you can volunteer or something at a local rental house and in exchange they'll hook you up.

Try to get your hands on a knowledgeable AC and he will guide you wisely through the land of focus pulling!

Either way best of luck on your shoot!

 

[Liam Hall]

I'm looking to shoot a short film on the Red with Zeiss standard primes, utilizing wide lenses the most. It is, obviously, a budget film, so pumping ridiculous amounts of light in to increase our DOF isn't going to be an option, and we will probably be sitting around 2.8-5.6, at 320 of course.

What is our DOF going to be? I want shallow DOF in general for this film, but I don't want to be limited in anything. Just how ridiculous is 35mm DOF with the Red?

Go borrow a Nikon D300 or D90, set the ISO to 320 and shoot some pics. You'll get the idea without having to swallow too much salt