cons to overloading tripod head?
 

Hi All,
I am finally upgrading from my 501HDV on Feisol legs. I am leaning strongly toward the Vinten Vision Blue based on the recommendations of Chris Soucy and others on the forum and elsewhere. The features and quality look great to me. As far as I can determine from the specs, the weight range on the Vinten should be fine for my HMC150 and also my GH2 with Gini rig, monitor, and follow focus (all together about 9 pounds 10 ounces). Even my stripped down GH2 on rails meets the minimum weight limit. However, if I add a matte box, the weight of my GH2 rig will surpass the 11 pound limit on the Vision Blue.

My question is this: what exactly is the downside to going over the weight limit on a video head? Is it just that it won't balance properly? Or are there other things that I should consider? I do much of my shooting without matte box right now, so overloading the Vision Blue would not be a regular thing. BTW, the Vision Blue is way at the upper limit for my budget, so going over $1200 is not really an option for me at this time. Any help in understanding the mechanics of the overloading issue would be very helpful.
Thanks.
Larry

Re: cons to overloading tripod head?
 

Why, Larry, you say the nicest things.

I think I can shed a bit of light on the subject.

The two MAJOR issues that are affected in an overload situation (I'll get to the minor ones later) are balance and counterbalance.

BALANCE:

The balance problem comes about owing to what is an industry wide misconception about how video pan/ tilt heads work, and even I hadn't had it rammed home, till fairly recently, when I was able to verify the problem empiracally with a special piece of kit.

Percieved Wisdom: The camera will balance perfectly, fall both forward and backward at an equal rate when pushed/ let go, when the COG of the rig is directly over the head tilt pivot point.

Truth: Simply not correct!

All the heads I've tested have the rig COG balance point significantly (1 - 1 1/2") forward of the TPP, meaning they are strongly biased in the "tilt up" mode.

I'll be honest, I have no definitive reason for this, it has come as a suprise to everyone in the industry I have asked for an explanation. That it has something to do with all that glass on the front end seems certain, but more than that I cannot say.

However, it does mean that when you approach the weight limit of the head, things can get more than a tad erratic in the balance department, as I discovered when doing the tests for my recent Vb5 review on DVinfo.

Once loaded to or past the weight limit of the head, the balance point started to simply move, as if by magic, as the two different spring rates (front/ back) degraded in different ways as the head was tilted, making the balance point a moveable feast.

I think it fair to say the head in question became something of a beast to control, as just when I thought it was balanced, it suddenly wasn't, and off it went, doing it's own "nodding donkey" thing as soon as the pan bar was let go.

So, not a good look.

[You can test this yourself with a great deal of patience, a QR plate and one of those hexagonal sided pencils/ pens. Fit the QR plate to the camera and spend the next half hour trying to get the rig to balance on the pencil on a desk, mark that COG point on the rig/ plate with a pencil.

Fit the camera to the head and balance it, note the COG of the camera in relation to the nominal tpp of the head (guess, if it's not a Sachtler), the former will be considerably further forward]

COUNTERBALANCE:

The very thing anyone buys a decent video head for - perfect counterbalance (amongst others).

Once you exceed the CB rating, you're right back to having to keep a hand on that pan bar at all times, even with judicious amounts of tilt drag.

Add in the problem produced by the BALANCE situation, you pretty well have an out of control head, how out of control determined by how much you have exceeded the weight limits and whether or not you ever get within a bulls roar of anything close to "balanced", as previously stated, almost impossible.

Then the "minors" are: stressing the tilt lock and drag systems if really abused, but the biggies are that you really don't want your video to look like it was shot on a Manfrotto 501, having spent all that money going upmarket.

If you're not too sure and not in a rush, don't sweat it, there's always something better "just around the corner" and sure enough, there is.


CS

Re: cons to overloading tripod head?
 

Chris, thanks for the detailed reply. Very helpful. And who would have thought that talking about video heads could conjure such a menagerie of metaphors about nodding donkeys, bull roars, and moveable feasts. It makes me want to recite Hemingway while finding the COG of my GH2. :-)

So if I unerstand correctly, the biggest drawback to overloading the Vision Blue is that i would lose much of the capability one would expect from such a nice video head. And a higher COG would effectively lower the upper limit of the head. I guess now I have to decide how often I plan to exceed the limit on the head and whether I can tolerate the regression to an unwieldy head on those occassions.

Your suggestion to wait and see what's around the corner sounds intriguing. Can you say anything more? Even about "ideal specs" for the "ideal" tripod in this niche? I'm eager to upgrade my current tripod, but I'd be willing to wait a little longer for a better match for my rig. I would hate to have to wait too long though. ;-)
Thanks again. Larry

Re: cons to overloading tripod head?
 

I have overloaded a few tripod heads. Chris' detailed testing of shifting balance points is very interesting.

Currently, my "big" head is a Gitzo G1380 (still a pretty small head by big-camera standards, 75mm bowl):
http://www.bhphotovideo.com/c/product/206505-REG/Gitzo_G1380_G1380_Video_Fluid_Head.html
I was so happy when I was able to perfectly balance the head for a new teleprompter system by installing a heavier counterbalance spring. An assortment of springs and a special allen wrench are included with the system. A small bother to do it, not an on-location operation, but it really works very well.

Since then, it's become my go-to head for unusual rigs... I've recently mounted a robotic panorama head for stills - the head and camera probably only weigh about 12 lbs, but, the rig is so top-heavy a much heavier counterbalance is needed.

I would rate their claim of supporting 2.2 to 22 lbs as true.

Summing up my experience, there's nothing "wrong" with overloading a head, excepting your camera is more likely to go over if you fail to lock tilt and walk away, and it can become difficult to do a smooth move during a shot.

PS. I don't know their line that well, but I've been very impressed with Libec heads, good value for the $.

Re: cons to overloading tripod head?
 

Chris you are a tripod Guru. :)
I learned a lot (again) from your post, so I thank you for that! I'll make sure to store this great piece of info somewhere for future reference.

Larry, good luck deciding. The Vision blue is a fantastic tripod. My FS100 feels very comfortable on one (translation: I never heard it complaint). I've owned a Manfrotto 501, not the HDV version btw, and it's almost impossible to compare the two. I would definitely recommend staying within the Vision blue payload range otherwise you would miss out on the magic that is called Perfect Balance. And of course because of the nodding donkeys Chris was talking about. ;)

Re: cons to overloading tripod head?
 

Larry.................

I can't really say much more, except that if you believe your rig is going to bust the Vb upper limit, give it a month or two, things are in the pipeline, and no, I have no dates whatsoever.

Conversely, if your rig is most definitely NOT going to burst the upper limits of the Vb, don't drag your feet, get one now.

(I think I may have just set myself up for a smack on the wrist, but what the hell).

Seth..................

The changeable spring heads definitely have/ had their place, the beauty being that any helical coil spring has only so much compresion before there is no adjustment possible, as it is fully compressed.

The down side is that there is no "middle way" with them, the springs work for just one mass/ COG and that's that.

If your rig doesn't sit within the top 5 - 10% of the springs capacity, it will be either too strong or too weak, meaning you are unlikely to get "perfect" counterbalance.

If the manufacturers had included some mechanism that allowed you to tension the spring, to up it's rating, they could have achieved pretty close to "perfect" without moving to the single fixed spring system, but, hey, they didn't.

I started my support journey proper with a Vinten Vision 3, which is probably a reworked Gitzo (they share the same changeable spring range) and had no end of grief with it till I worked out the physics and did a bit of accesorising.

[About this time I started my long association with Peter Harman, the then Vinten Product Manager, going on 7 years ago now]

I still have my V3, along with a 3AS, Vb and a Vb5, and for reasons I still can't fathom, a Sachtler FSB 6 on 75 CF sticks, oh, and a Manfrotto 503 (not HD) as a constant reminder of just how bad a head can really be.

Derran...............

I try to keep the troops entertained and informed.

You know the best thing about being a camera support Guru? {I am minded of the saying: "In the land of the blind, the one eyed man is King"}

There sure isn't a heck of competition that knows diddly squat about any of it.

It's like some video "black hole" swallowed the entire industry and information pertaining to it, whole.

The change to video, and HD video in particular, has brought the subject "front and centre" to so many new people as to be scary, heck you can now shoot in Panavision with a $10k (or less) camera ferchristsakes!

Watch out for those "nodding donkeys", they bite.


CS

Re: cons to overloading tripod head?
 

Thanks everyone. Your collective experience has helped to clear things up for me. I just need to evaluate my current and future tripod needs and make a decision to either go for the Vision Blue now or wait to see what's behind door number two. Hmmm...

And Chris, one-eyed or not, it's really great to be able hear your on the workings of video heads and tripods. Your systematic approach to your reviews gives your words credence that seems to be lacking from many other reviewers I have found on the net. Thank you.