Focal Plane and panning / tilting ?

Shooter

Shooter

Veteran
I viewed many of the adaptor rig photos in a previous thread and many seem so un balanced and extended that I was curious how the users have worked around the focal plane when panning and tilting.

Some users apear to have a rig balanced for the head without any regard to the focal plane (or axis of the pan). This creates a jib/pan effect with close subjects and can also affect the focus distance.

Where is the focal plane with a 35mm DOF Adapter? I assume its the GG in the adapter as so is well forward of the original lens to camera body attachment or the sensor. Theoretically this should be the axis for the head and the pan/tilt.

BTW: I get my adapter this coming week and it will be one of my first tests so I can set up the rig properly for my work. I do a lot of tabletop shoots.
 
Interesting ...no comments on this matter.

I have since viewed all the pix of DOF rigs in previous thread and conclude that many are grossly mis-setup in the regard to focal plane position and pan axis. (Also note that I consider some appear very well set up)

Seems some are set up purely to balance out on heads to light for the function. Loved one rig that measures over one metre long.

My Letus has just arrived and I look forward to the process of setting it up as I believe it should be. Will post pix when completed and hope I can get it well sorted. I was actually surprised how heavy the Letus Elite adapter is in real life!
 
The focal plane on a 35mm adapter is indeed the ground glass.
The best way I get closer to this plane is to use a longer camera plate (I have a 516 head, the long plate helps to get it closer.)
Long plate for a 516 head...
http://www.bhphotovideo.com/c/produ...nfrotto_357PLONG_357LONG_Pro_Video_Quick.html

Using a long camera plate and a Nodal fluid head would be best though. Nodal heads tend to be pricey, you don't see them much at this price level (there's typically cartoni and ronford, but varizoom makes a cheaper version which looks pretty interesting)

I enjoy seeing those meter long cameras as well... not sure how anoyone could ever do handheld with those setups. lol
 
A Ronford F15 would be a great head to use with these rigs. Nodal points for pan and tilt.

These DOF Adapters do raise the camera quite a way up from the head base plate.

I also intend to use a longer plate to achieve the set up.
 
Hi Shooter,

I'm new to DPing but are you saying the our GG's should be aligned or close to the pivot area of the Tripod Head ?
 
I have always believed that the focal plane is the nodal point of a pan. The point around which the rotation occurs.

It is more difficult to achieve for a tilt (without a rig such as a Ronford F15)

A good grip will always try and set up a camera and mount this way and it is usually easier for the operator to maintain eye contact with the eyepiece.

It is more aparent in very close work but the effect is more of a sweep (jib) movement if you have the f.p well forward of the nodal point.
 
Thanks for this post, Shooter, I'd somehow never even considered this as part of setting up a rig. It seems so obvious now that you've brought it up. I'll definitely keep it in mind next time I set my adapter rig on a tripod. If I understand right, it means the actual focal plane of the rig (the ground glass inside the adapter) should be close to the tripod head itself (or whatever is being used as a nodal point for a pan/tilt). When doing this on a 35mm adapter rig, wouldn't that result in most of the gear hanging off the back side of the tripod? How do you balance it out?
 
I am just setting mine up now (Letus Elite with an HVX and a mattebox) using a combination of the slide plates, rods and adjustments.

Looks like I will get fairly close to FP over centre of the pan axis (not exactly but thats o.k)

Until I get it all together, I wont know how the weight distributes but early indications are it will be fine. I will probably use an onboard monitor as the counter balance if required.

I am trying to keep it all neat, compact plus quick and easy to rig.

Will post pix once done.
 
I set up my adapter so the center of gravity isn't so high, makes everything much more stable. I don't understand why so many of the manufacturers decided to shim the setup further raising the center of gravity of the camera.
This is the setup i've arrived at. Tried to keep everything light, compact, and evenly distributed so I went with lens shade vs. a mattebox.
http://www.dvxuser.com/V6/showpost.php?p=1398089&postcount=187
 
The "focal plane over axis" concept helps to keep bring the focus closer one point in space. This is important for helping to keep focus on tabletop/circular moves where your sweeping the camera around a object.
 
Put another way.
Your eyes are near to being on axis with the rotation of your neck. You see the world quite differently when you are swung from your feet. :-)

Sometime in table top work I deliberately set the camera well off fp axis to gain an effect in a close up shot. Like a mini track with a sweep.
 
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