hd lens f-stop question

Rich Lee

Rich Lee

I shoot Pirates.
i've been searching trying to find a post i remember reading about hd lenses and how their dof compared to film lenses.

anyway...

is it true that a fast hd lens (im guessing like an f1.8?) is similer to shooting with an f4 film lens? Depth of field wise i mean....is that the case?

thanks!
 
It's not the lens, it's the focal length.

So to figure it out, you compare what focal length you need to use to get the same field of view, and then refer to a DOF chart or DOF calculator to find out what f-stop to use to deliver equivalent DOF.

A 2/3" HD camera, at 10mm, is about the same field-of-view as a 35mm movie camera at 24mm. So a multiplication factor of about 2.4. So, at 100mm, and f/2, 200' away, a 2/3" HD camera has a DOF from about 150' to about 280'. When switching to a 35mm camera and using the same distance to subject but a 240mm lens, you have to stop down all the way to f/11 to get the same DOF, according to the DOF calculator at:
http://www.panavision.co.nz/main/kbase/reference/calcFOVform.asp

So to directly use your numbers, you could say that the HD lens at f/1.4 is more like a film lens at f/8.
 
thanks Barry...i didnt realize the dof was that far off from hd to film with similer field of views.

thanks man
 
Again, it's not just HD -- it's 2/3". A 1/2" HD camera (like the forthcoming HDCAM-XD) will have even deeper depth of field, and of course the HVX/HD100/XLH1/Z1 all have substantially deeper depth of field as well.
 
of course...bad habit of mine to clump all hd cameras together...i was referring to the 2/3" chip variety.

danke Barry.
 
You must log in or register to reply here.
Back
Top