What zoom to buy?

[Norm53]

I put up a bird feed at the edge of a woods about 80 feet from my lunch table behind a french door. My Canon EOS Rebel T3i with EF 75-300 mm 1:4-5.6 will not bring into focus the birds, large and small.

What lens do I need to buy that will do the job? Cost is no object.

Thanks, Norm

[Norm53]

I finally found the benro gimbal bh3, but couldn't find many reviews, I suppose because of its newness.

Feisol UA-180 gets excellent reviews.

Lots of discussions at Photo Camel comparing the Wimberly II with the Mongoose 3.6:

The "Mongoose" looks kind of similar to the Kirk Enterprises "King Cobra" (I suspect it may have inspired the name somehow, too  ) in terms of it being a side mount. I prefer the full Gimbal, since with the "cradle" with the lens mount underneath the lens, you have the lens centered over the tripod. With the side mount, you get an odd off-centered movement that makes turning a bit awkward (unless, of course, you have the good fortune to have the exact lens that has the perfect tripod mount and lens barrel dimension such that it is precisely centered over the tripod mounted to your side-mount Gimbal).

This is an interesting point that you make. It is along the lines of some of my thinking in that when I looked at the side-mount I got the feeling that it could be potentially, or inherently, unstable in some situations - not sure which ones, but the wee bit of physics I took way back when, got me thinking about stability and I felt the cradled model such as the Wimberley or the Custom Brackets and other similar designs, where the lens is "over" the main, central axis of the tripod, just looked a bit more stable.

Knowing my physics, I'm persuaded that a cradle gimbal head is more stable than a side gimbal head.

Ah, decisions, decisions!

Norm

[Waddizzle]

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@Norm53 wrote:

bh3 gimbal did not compute at google. However, the ghb2 ought to get the job done. I'll order that one and fit it to the Manfritto tripod.

You mentioned Amazon.  Personally, I have never used the service, and doubt if I ever will. 

Googled the manfritto gimbal looking for reviews and up popped amazon. Have no intention of buying this equipment there. I use amazon extensively, but more for books, DVDs, and CDs.

Norm

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Sorry, that was a typo on the Benro model numbers.  That should have been the Benro GH2 and GH3 gimbal heads.  I would point out that the Benro heads come with a dust bag, to protect the head whether it is mounted on or off the tripod.

I sub-majored in Theoretical and Applied Mechanics in college.  The side mount gimbals are just as stable as the other design.  The side mount is just as centered over the tripod as the cradle mount.  In fact, I would expect that the side mount gives you more room to work with because the metal bracket is not in the way on one side.  Don't forget, you may want to reach out and adjust your lens from time to time.

The Wimberly WH-200 II has stellar reviews, but is a bit more costly than the Induro, Benro, or Feisol models that I have mentioned.  The Induro head also comes in a carbon fiber version, weighing in at 3.0 lbs. compared to 3.2 lbs for the aluminum.  The small weight gain for carbon fiber is not worth it to me.  However, carbon fiber will be stronger than a comparably sized piece of aluminum.

[Norm53]

The side mount gimbals are just as stable as the other design.  The side mount is just as centered over the tripod as the cradle mount.  In fact, I would expect that the side mount gives you more room to work with because the metal bracket is not in the way on one side.  Don't forget, you may want to reach out and adjust your lens from time to time.

Fine for stability and work space, but what about the Photo Camel reviewer's opinion on movement:

With the side mount, you get an odd off-centered movement that makes turning a bit awkward (unless, of course, you have the good fortune to have the exact lens that has the perfect tripod mount and lens barrel dimension such that it is precisely centered over the tripod mounted to your side-mount Gimbal).

Norm

[Waddizzle]

What do I think?  I think someone failed to properly balance their rig, or read the instruction manual.  That review seems to be more of an outlier, than anything else.

[Waddizzle]

I am not sure what that person is really talking about. It almost sounds like they are describing something like what is pictured just below, Induro GHBA, ball to gimbal adapter.

Notice how the lens bracket is on the side.  Is that what the person is talking about?  Those adapters may require spacers for some lenses, in order to center the lens over the panning axis of rotation.  If you lens is too big, and overshoots the center of gravity, then I guess you'd just be out of luck.  I would not recommend that type of device, at all.

[Norm53]

I think I'll go with the Waverley. Gets 5 stars from a bunch of reviewers. Therefore, if I can't get it right, then I know it is user error, not the head.

BTW, does the Monfrotto tripod have leveling bubbles? Bubbles are important say the Waverley reviewers. Or maybe the waverley head has the bubble(s)?

Came across an Oben CT-2381 carbon fiber tripod, which has excellent reviews. Anyone here had experience with it?

Norm

[Norm53]

A zillion Waverley users can't all be wrong, so the side bracket is not a problem.

Norm

[TCampbell]

I have an Induro GHB2 -- basically identical to the Waverly.

The critical thing is that it must allow the camera to be balanced both front to back (to keep it from being nose-heavy or tail-heave) and it also needs to allow a height-adjustment so that just as much weight is above the pivot axis as below the axis.  

Once you achieve that balance, the camera can be pointed anywhere, without having to snug the clutches, and the camera will remain pointed wherever you put it when you let go.

[Norm53]

The critical thing is that it must allow the camera to be balanced both front to back (to keep it from being nose-heavy or tail-heave) and it also needs to allow a height-adjustment so that just as much weight is above the pivot axis as below the axis.

Thanks for your reply. Two questions:

Can I assume that the only way that I will know that I have achieved proper balance is by turning the head knobs and testing movement "with my little pinky"? (Height of viewfinder must always be at a 4' above floor as I sit in chair.)

After I achieve the proper balance, will it stay that way when I change elevation at the main feeder, pan the ground under that feeder, and refocus to the hummingbird feeder at 30'? (The main feeder is at 64'). I don't want to be constantly adjusting for balance; that would be frustrating.

Norm

[TCampbell]

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@Norm53 wrote:

The critical thing is that it must allow the camera to be balanced both front to back (to keep it from being nose-heavy or tail-heave) and it also needs to allow a height-adjustment so that just as much weight is above the pivot axis as below the axis.

Thanks for your reply. Two questions:

Can I assume that the only way that I will know that I have achieved proper balance is by turning the head knobs and testing movement "with my little pinky"? (Height of viewfinder must always be at a 4' above floor as I sit in chair.)

After I achieve the proper balance, will it stay that way when I change elevation at the main feeder, pan the ground under that feeder, and refocus to the hummingbird feeder at 30'? (The main feeder is at 64'). I don't want to be constantly adjusting for balance; that would be frustrating.

Norm

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If you had a ball-head or a pan/tilt head then achieving "balance" would not be possible in any orientation because the pivot point is below the camera.  That means when you point the camera upward, you are moving the entire body of the camera farther back BEHIND the pivot point and that would ruin the balance.

But on a gimbal head, the whole point of the head design is that the pivot axis is literally located at the camera's center of gravity (in every axis).  This means when you tilt the camera to point upward, there is still just as much weight in front of the pivot axis as behind the pivot axis and as much weight above as below.  In other words... the balance wont change just becuase you change targets or point the camera higher or lower.    This is what makes it possible to leave the clutches loose on a gimbal head and yet still be able to point the camera anywhere you want (with your pinky finger if that's how you want to do it) and it will just "stay" wherever you point it -- without needing to snug anything down.

To achieve this balance on a gimbal head...

The camera mounts to a platform which works "like a swing".  But that platform is heigh-adjustable.  

Snug the clutches (knobs) on the gimbal mount.

Lower the platform down (the platform is called the "saddle"). Mount the camera LENS to the arca-swiss (dovetail) mounting plate onto the saddle and secure it, and then attach the plate to the platform.  The camera will be sitting too low at this point... but right now we just want to balance the camera front-to-back on that platform.  

Hold the camera stationary and loosen the altitude knob (that's the one that lets the camera point up/down and it's on the side of the gimbal head.)  Test to see if the camera wants to point up or down as you begin to release it (don't let it crash).  If it points "up" then the camera is tail-heavy.  But the arca-swiss (dovetail) mounting plate is basically a kind of rail... if you slightly loosen the saddle you can slide the plate either forward or backward in the saddle to shift the weight front or back.

When the camera naturally wants to sit "level" when you release it (doesn't want to point up or down -- but points at the horizon) then you've properly balanced the camera on the saddle ... front-to-back so that it is neither nose-heavy nor tail-heavy.

Make sure the arca-swiss rail is snugged tight in the saddle -- you're done with that adjustment.

Next ... raise the platform height.  Since the platform was basically at the bottom of it's travel limit, all the weight of the camera was "below" that altitude pivot axis.  What you want to do is raise it up so that 50% of the weight is above the pivot axis and 50% is below.  You'll find that when the axis of rotation is basically aligned to the center of the lens that you're pretty close.  You might need to adjust very fractionally up or down by perhaps just a millimeter or two... but it wont be much.

Snug the height adjustment and test the lens by point it up or down and make sure it stays where you point it when you let go (without needing to snug the axis).  If it wants to swing itself back level again then the center of gravity is still too low... raise it up very slightly.  if the camera wants to swing to point up or point down when you release it the the center of gravity is too high... lower it very slightly.    But when you find the point where it just remains stationary when you take your hands off it... then you've nailed the balance.