DOF calculator with still camera lenses

[wop]

Dear all,

I’m using still photography lenses on the red (shooting at 4k), and would love to find an accurate dof chart… can anyone help?

Given that there is a 1.6 (is this correct?) focal length multiplication factor, am I right in assuming that sites such as http://www.dofmaster.com/dofjs.html are not reliable?

Or does anyone know how the focal length multiplication affects the charts findings?

 

[Carlo Pisani]

I'm using still lenses too, and that question was always on my mind! Anyone got an answer?

 

[Martin Weiss]

DoF has nothing to do with what type of lens you are using. 50mm is 50mm is 50mm. Period.

The fanciest 50mm will have exactly the same DoF at a given t-stop as a 50 year old stills lens you pick up on eBay for 99 cents.

Any good DoF program will let you enter a specific Circle of Confusion setting which gives you the results you need for your chip size. David Samuelson's book is still a bible for camera assistants and DPs.

The field of view is what changes with different chip sizes.

 

[wop]

Hi Martin,

So as you are an owner, can you tell me what the circle of confusion is for the RED?

Thanks

 

[Miklos Konczol]

RED 1 CoC: 0.017

(correct me if i m wrong)

 

[wop]

Thanks for getting straight to the point xcm, really much appreciated.

 

[Martin Weiss]

CoC is also an asthetic choice - and depends on your shooting resolution and delivery format. I.e. if you know that the delivery format is HD you will have a bigger CoC than if you go for 4k projection.

For further reading, see Wikipedia and Reduser

 

[wop]

Ehm Martin,

Say you have to go on a shoot on RED, 4k HD, using a set of full frame photographic still lenses. Which accurate DOF chart would you use?

 

[Martin Weiss]

http://reduser.net/forum/showthread.php?t=9046&page=2

 

[wop]

Ehm Martin, for the second time,

Say you have to go on a shoot on RED, 4k HD, using a set of full frame photographic still lenses. Which accurate DOF chart would you use?

"Now can't you give me a STRAIGHT ANSWER anymore!!!"

 

[wop]

Ok Martin and all, thanks.

here's the straight answer. (hope it's right!)

For full 4K workflow and 4K filmout: 7μm
For 2K filmout: 10μm
For 1080 HDTV: 12μm
For SD TV and DVD: 25μm.