figuring out approx focal length at DVinfo.net

Darren D'Agostino · March 17th, 2008, 01:16 PM

I was wondering if there was any way to determine the approximate focal length of the XH-A1. I need to add some CG to XH-A1 footage that will be shot with the stock lens. However, it seems that there is just a slider in the viewfinder and no readout of what the approximate focal length would be.

Does anyone know a way to figure this out? Is there some setting in the preferences that will make this info appear in the viewer? If not, is there some formula to use based on points you can see, distance from the gate, parallax and all that jazz?

Btw, the shot will be locked off, no camera movement, so we can't use boujou to track it. While we will be setting up the cameras by eye in Maya, guessing the focal length can be a real pain, especially since this is a zoom lens the focal length may need to be a decimal value.

Any info will be appreciated.

Thanks

D

Dmitry Futoryan · March 17th, 2008, 02:14 PM

Hello Darren,

This is actually answered in another post:

http://www.dvinfo.net/conf/showthrea...hlight=a1+lens

In your settings on the A1, there is a Custom Functions feature that allows you to assign a numeric value to the zoom setting.

Find the chart in the thread above to convert the zoom numbers to 35mm focal lengths.

Hope this helps!

Darren D'Agostino · March 17th, 2008, 02:32 PM

I didn't see this when I did a search. Should do just what I need.

Thanks a lot for the help

D

March 17th, 2008, 01:16 PM	#1
Darren D'Agostino New Boot Join Date: Dec 2007 Location: NY, USA Posts: 19	figuring out approx focal length I was wondering if there was any way to determine the approximate focal length of the XH-A1. I need to add some CG to XH-A1 footage that will be shot with the stock lens. However, it seems that there is just a slider in the viewfinder and no readout of what the approximate focal length would be. Does anyone know a way to figure this out? Is there some setting in the preferences that will make this info appear in the viewer? If not, is there some formula to use based on points you can see, distance from the gate, parallax and all that jazz? Btw, the shot will be locked off, no camera movement, so we can't use boujou to track it. While we will be setting up the cameras by eye in Maya, guessing the focal length can be a real pain, especially since this is a zoom lens the focal length may need to be a decimal value. Any info will be appreciated. Thanks D

March 17th, 2008, 02:14 PM	#2
Dmitry Futoryan Regular Crew Join Date: Feb 2008 Location: Minneapolis, MN Posts: 37	Hello Darren, This is actually answered in another post: http://www.dvinfo.net/conf/showthrea...hlight=a1+lens In your settings on the A1, there is a Custom Functions feature that allows you to assign a numeric value to the zoom setting. Find the chart in the thread above to convert the zoom numbers to 35mm focal lengths. Hope this helps!

March 17th, 2008, 02:32 PM	#3
Darren D'Agostino New Boot Join Date: Dec 2007 Location: NY, USA Posts: 19	I didn't see this when I did a search. Should do just what I need. Thanks a lot for the help D