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08-16-2021, 01:35 PM - 3 Likes   #1
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DIY load balancer / QR assembly / BG adapter

My problem was this: I'd gotten battery grips for both the KP and the K-1, but my Benro gimbal head wouldn't work with the BG's attached. Insufficient clearance between the bottom of the grip and the arm of the gimbal. So I invented a gizmo to raise the QR clamp up a bit to allow for the extra space needed.
Then I found out the thing I'd made was brilliant for balancing various camera and lens combinations.
What I did was to buy two "Promaster macro focusing rails" (the cheapest, no gears, no screw drive, still about a hundred bucks each). Each one comes with a long rail with Arca grooves cut in the upper and lower edges. The upper part consists of a small squarish set of two clamps hooked together at right angles by a screw set in the center. So, now I've got two of each component, the rail itself and the QR clamp that goes with it.

I used an allen wrench to unscrew each of the clamp-sets to rotate one of the two parts of each ninety degrees so the knobs that control tension on the clamp set opposite to each other. I used one of the rails as a very long Arca plate on some lens or another, and mounted both of the clamp-sets on top of the remaining rail, which in turn, gets mounted in the gimbal's clamp.

So now I've got all kinds of front-to-back adjustments. In the pictures below (assuming I'll be allowed to post), you will note the gizmo is holding up a KP with an old FA* 300mm f/4.5 attached, as well as a K-1 with a DA 560mm f/5.6 attached. The KP is mounted pretty far over to one side, while the K-1 is pretty far over the other way, because that's what it took to balance the weight of the combinations on the gimbal.

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PENTAX K-1  Photo 
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Last edited by dlhawes; 08-17-2021 at 05:28 AM.
08-16-2021, 02:18 PM   #2
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is it 160 or 200mm QR plates ( top and bottom ) ?

Last edited by nixxo2002; 08-16-2021 at 03:01 PM.
08-17-2021, 06:08 AM - 1 Like   #3
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QuoteOriginally posted by nixxo2002 Quote
is it 160 or 200mm QR plates ( top and bottom ) ?
The rail is 200mm, the QR plate on the 560 is 210mm, and the one on the KP (the one with the footless 300 attached) is about 40mm (actually almost exactly an inch and a half). I bought the extra long plate for the 560 as "overkill", not knowing exactly how I would be using it at the time that I bought it.
Here's a picture of the 560 with the plate attached.
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08-18-2021, 03:06 AM   #4
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A couple of additional observations:

I like the fact that I'm using two small clamps because I can spread them as widely as necessary to make me feel that the plate/foot is solidly attached, as in the picture above showing the foot of the 560. I think the weight and stress is better distributed that way. Also, there is a value in the redundancy because if one clamp were to fail (or the idiot photographer forgot to tighten it up right) the other holding fast would give me time to grab the thing and get it right. And in the case of the K-1/560mm combination, the rearmost part of the 560's foot is forward of the front-most section of the gimbal's clamp, which means that proper balance could not be achieved without the gizmo because I'd have to mount the 560 too far to the rear of the combination's center of balance. Also, the fact that the "macro focusing rail" is a good bit thicker than a single QR plate makes me think it'll be strong enought to support the weight of that heavy combination even though it's mounted off-center relative to the center of the gimbal's clamp.

Secondly, I should point out that the big blue knob is the central point on the gimbal's clamp, and thus represents its balance point. Note that the KP is mounted to the rear of the blue knob and the 560 is mounted forward.

08-18-2021, 04:05 AM   #5
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I am not sure I understand the problem you are trying to solve.

With the K1 attached to the DA560, I use a 168mm plate ordered off eBay and it balances on my JOBO Jr gimbal mount, and I don’t have any “interference” and my balance point is exactly where you show it, under the serial number band.

The issue I have with the gimbal mount is vibration induced by the flexibility of the swing arm. I removed it and put the acra Swiss mount directly on the swing arm pivot,

All your scheme achieves is raising the lens up from the bottom of the swing arm, but the swing arm can also be raised. What I see is many parts that can easily be deleted while achieving the same result, and every part added, adds potential for vibration
08-19-2021, 04:01 AM   #6
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QuoteOriginally posted by Lowell Goudge Quote
I am not sure I understand the problem you are trying to solve....
All your scheme achieves is raising the lens up from the bottom of the swing arm, but the swing arm can also be raised....
"ProblemS", plural. The central problem is the lack of clearance between the battery grip and the swing arm. Sure, I can raise the swing arm clamp, but that doesn't change the distance between the QR plate on the bottom of the battery grip and the vertical portion of the swing arm. No doubt it's because of the dimensions of my particular model of Benro gimbal, and other mfgrs'. models will be different in that respect. This is only a problem when I'm mounting a camera on the gimbal with a wider angled lens instead of a long-lens' "foot". So the main problem was simply to raise the height of the camera/BG above the point at which the triangular support component of the gimbal would interfere with the bottom left edge of the battery grip (as viewed from the rear of the camera). The load balancing aspect is an after-discovered bonus. Thing is, I don't like mounting and de-mounting hardware. I can leave this thing on the gimbal and use it for all purposes, I don't have to be taking it off and putting it back on depending on which lens or camera I'm using.


QuoteOriginally posted by Lowell Goudge Quote
...The issue I have with the gimbal mount is vibration induced by the flexibility of the swing arm. I removed it and put the acra Swiss mount directly on the swing arm pivot,
... every part added, adds potential for vibration

I don't get any of that at all. Are you referring to vibration from the ground transmitted through the tripod & head? Or do you figure that extra components vibrate for some other reason? Since vibration (i.e., low frequency sounds) move through solid materials pretty well over long distances, I can't see that extra bits of metal in the assembly will make any difference as to vibration. I'd be interested to know why you feel that would be a problem.
08-19-2021, 07:46 AM   #7
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So it's $200 for two sets:
MR1 Macro Focusing Rail with quick release

How could it be modified into holding the DA560 and the camera on one rail to reduce vibrations even more?

08-19-2021, 09:34 AM - 1 Like   #8
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QuoteOriginally posted by dlhawes Quote
"ProblemS", plural. The central problem is the lack of clearance between the battery grip and the swing arm. Sure, I can raise the swing arm clamp, but that doesn't change the distance between the QR plate on the bottom of the battery grip and the vertical portion of the swing arm. No doubt it's because of the dimensions of my particular model of Benro gimbal, and other mfgrs'. models will be different in that respect. This is only a problem when I'm mounting a camera on the gimbal with a wider angled lens instead of a long-lens' "foot". So the main problem was simply to raise the height of the camera/BG above the point at which the triangular support component of the gimbal would interfere with the bottom left edge of the battery grip (as viewed from the rear of the camera). The load balancing aspect is an after-discovered bonus. Thing is, I don't like mounting and de-mounting hardware. I can leave this thing on the gimbal and use it for all purposes, I don't have to be taking it off and putting it back on depending on which lens or camera I'm using.

Ok that explains why I didn’t understand the issue, I only use the gimbal for super tele applications

QuoteQuote:


I don't get any of that at all. Are you referring to vibration from the ground transmitted through the tripod & head? Or do you figure that extra components vibrate for some other reason? Since vibration (i.e., low frequency sounds) move through solid materials pretty well over long distances, I can't see that extra bits of metal in the assembly will make any difference as to vibration. I'd be interested to know why you feel that would be a problem.
Here is the vibration due to added components between the tripod and the lens/camera. When you mount a super tele to the tripod, even if the tripod itself is stable, there can be vibration of the camera / lens with the mount itself. I found on the JOBO Jr. for example the “L” shaped swing arm is flexible. The main bracket is about 25mm diameter tubing, but the “L” is a 30mm x 12 mm channel with about a 3 mm thickness it has some flex.

To test this just tap the lens when looking through the view finder, and you will see the image shake.
08-19-2021, 05:08 PM   #9
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QuoteOriginally posted by angerdan Quote
So it's $200 for two sets:
MR1 Macro Focusing Rail with quick release

How could it be modified into holding the DA560 and the camera on one rail to reduce vibrations even more?
Unless what you mean is to mount both the camera and the lens on the same rail at the same time, that's exactly what I'm doing with it. I can mount either the camera or a long lens just not both at the same time (though a big reason for that is that the bottom of a lens foot doesn't stick out so far as the base of the battery grip).
08-21-2021, 05:07 AM   #10
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Oh, and as to reducing vibration further, I don't think it's possible. I'd thought you could put a layer of Sorbothane between two or more of the layers, but the vibration would still be transmitted through the screws. Where do we suppose this vibration is coming from, anyway? I'm thinking if it's from nearby roads or train tracks, or if from the wind, or from the shutter going click, I don't see as how anything but a fast shutter speed is going to make any difference. And if there were so much vibration that it would really affect the shot, then the image stabilization ought to be on, because as long as it's got some real movement to measure and compensate for, it's not going to get into a feedback loop, I should think.
09-15-2021, 12:01 AM - 2 Likes   #11
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what you would need is a long lens support bracket, in reversed position
I use the 12in Hejnar Photo one (12 Inch Heavy Duty Lens Support Package With Quick Height Adjustment) on my FA* 250-600, in a reverse position, i.e. the vertical bracket with rolls support the barrel near the camera body, like in the photo below.


P1040206.jpg

helps a lot to reduce vibrations...

but with a gimbal it add restrictions to shoot right upward...
But Nowadays I am using a Video Head instead of a gimbal, and all is good and smooth ! (Benro S8 in the following photo)


IMG-20150102-01847.jpg
by Sylvain Côté, on Flickr
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