Manfrotto 503HDV - Aligning the half-ball

[Nick Wilson]

Hi

I have a 503HDV head which comes with a half ball adaptor for the 75mm bowl. The adaptor is attached by a central threaded rod and nut, with three grub screws to set the alignment between the head and half ball.

On a shoot, the head worked loose from the half ball, and to continue the shoot I just tightened everything. Now, the alignment is out in that if I level the head, then turn it through 360 degrees, the bubble drifts off centre before returning. The discrepancy is not huge, but I would like to adjust it out. Is there any procedure or tips about the quickest way to set up the head so it stays level throughout any pan?

Many thanks,

Nick

[Paul R Johnson]

If the head goes out of level as you spin it then something odd is happening. To do this, the bottom of the head, with the bolt that goes into the ball must be changing it's alignment to the top of the head - which unless the joint is actually loose, should be impossible? Are you sure the head isn't spinning on the ball to bottom plate bolt rather than the real joint?

[Greg Boston]

Originally Posted by Paul R Johnson

Are you sure the head isn't spinning on the ball to bottom plate bolt rather than the real joint?

I think that's what he was saying. Something isn't quite level where the base of the head mounts to the half-ball adapter.

Using a circular level, I would place the head with half-ball and tightening post upside down on a known level surface. Then, placing a circular level on the inverted tightening post should yield a level reading as well. If it doesn't, make your adjustments until the two agree with each other.

-gb-

[Nick Wilson]

Yep - the head and the tightening post are not an exact right angle. Greg - thanks for your suggestion but I am not sure if I could get it to work. It would seem to rely on having no tilt between the top and base of the head, and I don't think that the end of the tightening post is sufficiently flat to get anything meaningful from putting a spirit level on it.

What I have tried is marking the half ball, then levelling the head, turning it 180 degrees, seeing which way the bubble moves and tightening or slackening the 3 grub screws to try to eliminate the bubble movement. However, I just end up chasing the error. I guess the right approach is similar, but I am probably missing something obvious!

Cheers,

Nick

[Chris Soucy]

I think the problem is your perception that the three grub screws are there for leveling the head with respect to the half ball.

As far as I know, they're not.

I believe that when the head has been screwed down tight onto the half ball such that the head base is flush with the face of the half ball, perfect alignment is acheived.

The three grub screws are to ensure that at least one will engage in the appropriate lock indent on the underside of the head to prevent it rotating back off the half ball.

My suggestion:

Back off all three grub screws, remove head from half ball and ensure all three grub screw points are below the face level of the half ball.

Replace the head on the half ball central bolt and screw it down till the pips squeak (no tools required - hand pressure only!)

Tighten all three grub screws ditto (screwdriver mandatory for this bit)**.

Now, unless there is some serious alignment issues with the head base or the half ball central bolt, the leveling bubble should stay centred at any point in a very very slow 360 pan (bearing in mind that there wouldn't be many heads that won't show SOME deviation under the same circumstances).


CS

**If you find that none of the three grub screws has engaged an indent, it may be necessary to back the head off just a tad, tho' that's pretty unlikely

[Nick Wilson]

Chris

Many thanks for your suggestion - I will give that a try.

Cheers, Nick