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DemonDuck
10-26-2010, 05:40 PM
I bought a T-II in hopes that it would provide a more consistent alignment of my Panasonic LX3. It doesn't. Here's why.

The length of the camera plus an extension tube and wide angle lens adapter is such that I can't move the camera back far enough on my NN3 so as to put the lens at it's proper no parallax point. I must reverse the T-II so that the attachment point is underneath the extension tube. I have to also do that with the T-30.

The problem is that the bumpers on the T-II then push against the front of the camera which is ok but the distance between the bumpers is not wide enough to allow the extension tube to fit in between.

So I can't use the T-II in it's normal orientation because it doesn't allow the camera to be put at the no parallax point and I cannot reverse the T-II because the distance between the bumpers is not wide enough for the extension tube.

Using the previous T-30 is also a poor choice because the distance from the tripod mounting hole to the optical center line is about 22mm. That makes a fairly long lever arm about which the camera twists because of the weight of the wide angle lens.

Given that large sensor cameras are getting smaller and compact cameras are getting better, I think there should be more thought put toward developing gear that supports effective use of those cameras. The NN3 is a good size -- actually a little big for EVIL's and compacts but it can work if you think through the simple adapters that gives a solid and well aligned support.

DD

nick fan
10-26-2010, 09:15 PM
You see it is difficult to have a simple design to fit all P&S cameras.
You can use the T-adapter II without using the anti-twisting pins. Just unscrew all the parts. I guess using polymorph to make a custom anti-twisting flange is the simplest solution for you.

nick

DemonDuck
10-27-2010, 10:56 AM
Fanotec
We listen. We try harder.

nick fan
10-27-2010, 10:59 AM
I will see if I can add anti-twist feature to both sides T-adapter.



nick

DemonDuck
10-30-2010, 04:35 PM
Here's something else to think about --

On my LX3 (not a cheapo P&S) the tripod hole is offset 22mm from the optical center line -- to the best I can determine.

The space between the anti-twist bumpers is about 36mm or from the center of the mounting hole -- about 18mm from the mount hole center line.

So that means that one bumper is "inside" the tripod socket. That means that while there is good resistance to twist one way, there is no resistance to twist the other way. This may be hard to visualize. I suggest you try a test to see what I mean.

I think the bumpers are only going to work in some instances. Perhaps a lipped plate like the Camera Mounting Plate CP2 in a track and a locking screw instead of the double bumpers might give a better alignment and resist twisting. It doesn't have to be very wide or very high. 0.5cm above the cork friction pad and 2cm wide would work on my camera. But because of the potential for twist I described above, two opposing lipped plates might be needed.

I offer these thoughts not as complete solutions but just as observations for the purpose of brain storming.

Possibly the simplest solution would be a lens ring type attachment that would fit around the adapter tube. It's about 48mm in diameter and about 2.5cm long. The lens (adapter) ring would just fit into the arm of the NN3 like an ordinary mounting plate. That would be much, much simpler. You could make it such that the stand off distance would be large enough to handle the sometimes very big adapter lenses that can be used with the high end compacts. Think about the Nikon FC-e9. Or look at the size of this wide angle adapter lens designed for the LX3 --

http://cgi.ebay.com/Panasonic-LUMIX-DMW-LW52-Adaptr-DMC-LX3-/120639147185?pt=Camera_Lenses&hash=item1c16a74cb1

That's huge. Even if you redesigned the T-II, there just wouldn't be enough clearance to put that lens on a NN3/5/XXX. And with a lens (adapter) ring, there wouldn't be the huge amount of torque on the tripod screw when using a big lens like the FC-e9 which weighs 17.5 oz.

I don't think any one solution will solve every mounting problem.

DD

nick fan
11-01-2010, 09:57 AM
Here's something else to think about --

On my LX3 (not a cheapo P&S) the tripod hole is offset 22mm from the optical center line -- to the best I can determine.

The space between the anti-twist bumpers is about 36mm or from the center of the mounting hole -- about 18mm from the mount hole center line.

So that means that one bumper is "inside" the tripod socket. That means that while there is good resistance to twist one way, there is no resistance to twist the other way. This may be hard to visualize. I suggest you try a test to see what I mean.
I think the bumpers are only going to work in some instances. Perhaps a lipped plate like the Camera Mounting Plate CP2 in a track and a locking screw instead of the double bumpers might give a better alignment and resist twisting.

Hi DD,

Thanks for your suggestions. I can make a plastic bar to replace the plastic pins. Beside I will add anti-twisting feature in the opposite side as well. I can make a mod to the mold to add this function.



Possibly the simplest solution would be a lens ring type attachment that would fit around the adapter tube. It's about 48mm in diameter and about 2.5cm long. The lens (adapter) ring would just fit into the arm of the NN3 like an ordinary mounting plate. That would be much, much simpler. You could make it such that the stand off distance would be large enough to handle the sometimes very big adapter lenses that can be used with the high end compacts. Think about the Nikon FC-e9.

This was also on the to do list. I just need to focus on the more important and profitable items first. I have more than a dozen products to develop.

Nick

DemonDuck
11-01-2010, 12:32 PM
Very good. Looking forward to a solution to the twist and alignment problem that cameras (any camera) with offset tripod holes have.