Rack focusing

C

colinmday

Member
I have heard from nemerous people that you can program different focal distances to the User buttons allowing you to rack focus with the push of a button. I hope this rumor is true as it would be very easy to accomplish multiple racks with great accuracy. Has anyone else heard of this feature and if so, do you know how to set it up?
 
I don't think you would like a "mechanical" rack focus either. It probably wouldn't look very natural/smooth, and be very absolute and precise, in a bad way.
 
The HVX doesn't provide such a capability via a button press, but it's very, very easy to get an absolute precise rack focus just by using the focus ring.

In addition, the remote focus port appears to allow repeatable positioning, so it should be possible for aftermarket vendors to make a programmable focus control.
 
Thanks

Thanks

I usually use a follow focus knob. I was just thinking of a very specific shot where this would have looked cool, and wanted to know if it is capable. The more I think about it, I would much rather have total control over the speed in wich I rack.
 
There is something great about the independent / guerrilla filmmaking scene, where we talk about recalibrating rubber bands. It's so dynamic, I love it.
 
There's a follow focus trick I learned which may be useful when you need to rack yourself while operating and you're in a pinch. Take a piece of gaffers tape and de-tack the length of the center portion whichever way you choose. You can use another piece of tape face to face to do so and what you get is a length of tape with two sticky ends.

now mark end focus position by applying one end to the camera and the other end to the focus wheel in such a way that their is no slack AND it slackens in the direction of the starting position.

You're now set to follow or rack blind once you find the start position and turn until you hit the custom stop. And this little device can be easily reused until you lose tack.


- enjoy
 
film plane

film plane

When you are measuring distance from your subject, where exactly do you measure to on the HVX? I know on 16mm and 35mm you measure to the film plane. Do you estamate where the CCD is? Is it right where the lens ends?
 
For my rack focuses on my DVX I just use the numbers... find a focus on the second subject... remember the number... get the focus on the first subject, then rack to the second number...
 
colinmday said:
When you are measuring distance from your subject, where exactly do you measure to on the HVX? I know on 16mm and 35mm you measure to the film plane. Do you estamate where the CCD is? Is it right where the lens ends?
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we did some testing checking the lense distance accuracy.....measuring from the back of the lense barrel (where the lense meets the body) to the subject. The focus was DEAD on with the lense markings.
 
briceman said:
For my rack focuses on my DVX I just use the numbers... find a focus on the second subject... remember the number... get the focus on the first subject, then rack to the second number...
Click to expand...
What Briceman said . . . For me, using the numbers of the viewfinder's focus index is the easiest way to do precision focus pulls without a camera assistant. Super-repeatable. Super-easy. Super-accurate.
 
hey, sure thing...just passing on little nuggets that I learned.

I don't know about the rest of you but I find it tough to frame a moving subject well that's also moving toward or away from camera, while trying to hit focus marks. How many times do you find yourself undershooting or overshooting...for me, all the time . This little trick lets you concentrate on the framing.
 
My dp acutally got a really good rack focus on the xl2 I'll post a clip as soon as I can.

By the way he said he got lucky!!!
 
Couple of points - first if you just use the numbers you need to keep in mind that there are changes in focus within a single number - not sure the increments but you can be tack sharp and slightly off all within one number - just good to know if you want to be precise.

Also, according to the panny manual the distance for focus is only approximate - do not use it for critical focus
 
dailyrushes said:
Also, with a little practice, you can learn to rack focus by "feel", the position of your wrist as you turn the focus ring back and forth between two positions.

It works for me on an intuitional basis rather than having to go into an analytical mode and translate numbers into hand-eye coordination. This may not work for everyone!
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That's true for certain situations and if you don't have too big a distance to rack between. It's tough to do that on the hvx due to the large focus ring and can be pretty difficult with shallow DOF when you're zoomed in.
 
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You cannot rack by feel in HD if you want a tack sharp picture - you need to be precise with all those pixels on the screen - and you cannot judge by the lcd unless you zoom in and use focus assist and dtl.
 
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