Why Do Anamorphics Have Shallower DoF?

[Rob Ruffo]

DIT'd by me

Alexa, unsqueezed the transcodes by cutting the height in half in Resolve, looks like that's what they did in post as well

Forget which lenses, it was over a month ago

How many days was the shoot? What was the budget? I'd be grateful for any info you can share.

 

[Peter Dmitriyev]

Rob: landmark is a strong word ..but it's definitely one of the better and more cinematic videos coming out in recent times and I do personally think Mandler is the best and does the most cinematic work

 

[joe hedge]

How many days was the shoot? What was the budget? I'd be grateful for any info you can share.

2 days, 2 cameras, no idea on budget

 

[Nick Gardner]

One thing to throw in here because it is often misunderstood and it annoys me, is that longer lenses DO NOT have shallower depth of field than wide lenses. If you shoot a close up on a 50, and fill the frame with the subjects face, the dof is exactly the same as if you had shot the same shot on 25 and moved in closer. The only things that affect dof are image magnification and f stop-hence, the shallower dof on anamorphic, as you are magnifying the image more than on spherical 35. The practical way of doing that is using a longer focal length to get the same fov, however the longer focal length doesn't have any shallower dof than a wider one.

Look at it in the extreme - say you are shooting a campfire scene with 4 people sitting around a campfire, You are nice and close and you want to get everybody in the shot so you throw up an 18mm. Nice! everyone is in the movie and everyone is more or less in focus. Now, throw up a 300mm and take a hike way back. By the time you get the same wide shot with all 4 people in it, you are so far away, that the dof is the same as the 18mm and every one is still in focus. The dof doesn't get more shallow until you start making the people bigger in the shot, ie magnifying them more. Of course the angle of view changes, and the perceived dof is arguable, but the hard facts as to what the dof is remains the same.

Thanks for listening to uncle Nicks crazy old man ramblings. Tune in next week for "Get those damn Kids of my lawn!" and "why is that guy yelling at a chair?".

Nick

 

[Nick Morrison]

If you shoot a close up on a 50, and fill the frame with the subjects face, the dof is exactly the same as if you had shot the same shot on 25 and moved in closer.
Nick

Except the 25mm "closeup" will have wide angle "HERO" distortion, while the 50mm will look more flat and compressed ...so they won't LOOK identical at all, even if the background falls off in a similar way.

 

[Nick Gardner]

Except the 25mm "closeup" will have wide angle "HERO" distortion, while the 50mm will look more flat and compressed ...so they won't LOOK identical at all, even if the background falls off in a similar way.

Which is exactly why i said this -

Of course the angle of view changes, and the perceived dof is arguable, but the hard facts as to what the dof is remains the same.

Talking specifically about DOF.

Nick

 

[David Mullen ASC]

In this case, however, because the anamorphic lens "sees" a greater view horizontally, it acts like a wider-angle lens but retains the actual depth of field that comes with its focal length, so when comparing an anamorphic-lensed image to one shot on a shorter spherical lens to match the same field of view, you aren't changing distances to match FOV -- a 50mm lens set to the same f-stop and distance as a 25mm lens has less depth of field. In other words, you can treat the anamorphic image as if you had doubled the width of the film format or sensor size and had used a spherical lens.

 

[Nick Gardner]

In other words, you can treat the anamorphic image as if you had doubled the width of the film format or sensor size and had used a spherical lens.

And that is precisely what I am saying. You are effectively using a larger negative, and enlarging the image more to get the same sized shot.

Nick