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el_stupido
03-26-2008, 06:42 AM
i come to you, my more experienced peers for advice...

Coming from the mini DV world, I'm about to do a shoot for a short film using prime lenses. I've tried to read as much as I can (i buy american cinematographer etc etc & wikipedia is excellent for F-Stop/T-Stop explanations) before diving in on using them... I'm a little scared I'm going to end up with dark & out of focus rushes.

So I just want to ask though at the risk of being bludgeoned to death: what are you doing when you use a tape measure and measure how far away something is from the camera? Once you have that measurement, what are you adjusting on the lens? How does that help you focus/pull focus????? I can't find a 'how to' online anywhere...

Any advice/tips for a virgin prime lens shooter would be appreciated!

go on... pop my cherry. :love:

El Stupido

PS: Shooting with HVX202 & P+S Technik Mini 35 adaptor.. can't wait to use RED, but not booked out for the weekend I am shooting :waaa:

Davide B.
03-26-2008, 06:54 AM
You use the tape measure to figure out what the focus distance to the object in front of the lens is. The measurement of the tape measure can be combined with the DOF markings on the lens to see what is in focus. So if you measure your actor as being 9.5 ft. from the lens, then set the focus distance on the lens at 9.5 feet. You should then double check your focus by looking at a monitor.

I just put those numbers into a DOF calculator assuming a 50mm lens and an f-stop of 1.4. Everything from about 9.9ft away to 9.13ft away would be in focus: not that much at all.

Two things will make your life much easier: a good HD monitor and a good focus puller. You'll need a hi-def monitor to be able to tell what is in focus and what isn't when shooting with the HVX. I heard that the Panasonic monitor is great for this. And a focus puller would also be really helpful. They can take care of taking all the measurements and pulling focus to make sure that you're talent is never blurred out. Then the only thing you'll have to worry about as a director is making sure that your actors hit their marks.

Mike Van Laanen
03-26-2008, 07:27 AM
Davide, which Panasonic monitor are you speaking of?

ericyoung
03-26-2008, 08:34 AM
[QUOTE=davide;182570]You use the tape measure to figure out what the focus distance to the object in front of the lens is. The measurement of the tape measure can be combined with the DOF markings on the lens to see what is in focus. So if you measure your actor as being 9.5 ft. from the lens, then set the focus distance on the lens at 9.5 feet. You should then double check your focus by looking at a monitor...QUOTE]

On page 8 of the downloadable operator manual, the focus hook labelled "A" is where you measure from the adapter to the subject you want in focus.

http://www.pstechnik.de/en/downloads/MINI35%20Manual_050216.pdf

Davide B.
03-26-2008, 07:50 PM
You're right, you do measure from the film plane, not the lens. My mistake. The monitor I was speaking of is this:
http://catalog2.panasonic.com/webapp/wcs/stores/servlet/ModelDetail?displayTab=O&storeId=11201&catalogId=13051&itemId=114038&catGroupId=14625&surfModel=BT-LH80W
There is a review of it here: http://www.dvxuser.com/V6/showthread.php?t=129780

davide

Cail Young
03-27-2008, 07:58 AM
You're right, you do measure from the film plane, not the lens. My mistake.

On the Mini35 there's a white line painted around the adapter marking the ground glass plane, which you should measure from.

el_stupido
03-27-2008, 04:32 PM
guys thanks for this info, thanks heaps!

El Stupido