Another video of the same product, just a bit shorter and more casual.

How do rails mount to the cage for a follow focus?

Think I've sussed it. From the same manufacturer - http://jag35.com/new/products/bottom-rods/

I'd be very surprised if they didn't fit their GH2 cage as well

When I was test-driving this rig, i used things like this http://jag35.com/products/railblock.html and this http://jag35.com/products/dslrstand.html. That's because that's what was handy, but lots of companies make that kind of thing.

Had an email conversation with David Aldrich from D-Focus about this product. Went like this:

Me: Question: Are you guys also designing a rail block to mount to the bottom of the cage? That's the other thing that is wonky with the GH2, getting the lens the correct height off the rails. My concern is that if you're counting on us to use a baseplate from somewhere else, by the time you factor in the height of a baseplate (even one that has height adjustment) and then add in the height of a quick release clamp and quick release plate, and then add the thickness of the cage, there's a good chance your way too high. If you have that problem already addressed, great! I'd love to hear about your solution.

Dave: I do have a rail block planned, but it's pretty tricky with the GH2 as I want there to still be access to the battery door.

In the mean time, the GH2 in the cage, mounted on a JAG35 DSLR baseplate is just slightly higher than the 85mm standard and should work fine in most cases.

Me: Sounds pretty good. How are you mounting the GH2 to the Jag35 baseplate and preventing it from rotating?

Dave: Nothing to prevent it from rotating other than friction at the moment. It works pretty well though. More secure than I would have expected.

@airboxlights - did the jag35 railblocks work ok with the cage during your road test? I like their other stuff very much.

Funny that you raise this... the cage did swivel around a bit on top of my quick-release plate. It was a little annoying. Soluble though. I had the cage mounted on to my Lanparte base and all the other crap you see mounted to the top of the cage. The lanparte base does have a little spring loaded pin going up into a second hole on the cage, but with all that torque on it (top handle, lights, etc.) sometimes the little spring loaded pin would slip out of hte whole. Very viable solution is just using a second 1/4-20 captive screw in the slot in the quick-release plate. I didn't have a screw like that with me, but it would solve the problem since the cage has sumerous threaded holes in the bottom.

The only JAG35 railblocks I used in that setup were a 2-rod railblock on top of the cage to use for the top handle, and one single railblock to noga arm to hold the sound rig. Those worked fine. The 2-rod railblock swiveled a bit on me because it's one screw that both tightens the railblock to the cage and bites down on the rods to keep them from slipping. Just one screw and all that torque from the carry handle, not going to work in the long term. Would need two of those railblocks in a row to give me two screws into the cage or else need a different railblock.

I'm in .. @vitaliy .. I feel this might be worth a special deal if you were able to arrange, considering the number of GH2 users :) .. pretty please have a go

@B3Guy .. watch the videos .. he details held by 1/4 thread in base, by flash shoe at top, and there are two knobs/lumps which also prevent rotation.

Someone mentioned Rewo production problems. Is there a known reason why the Rewo GH2 Cage isn't currently available? I have emailed and tweeted them asking when it will be back and available for purchase and heard nothing back. Quite annoying.

@plasticated ReWo guys are very likable but their focus is not on the business with ReWo products. As @Vitaliy_Kiselev mentioned they are mostly busy with shooting and directing. I bought a cage months ago and they sent me the wrong plate for hot shoe mount (from 7D which is slightly different) I am in personal contact with one of these guys and it was promised several times to be sent "today" but I am still waiting for it. Regarding GH2 cages I was told that one of their main supplier is out of business due to insolvency and all CAD tools they paid in advance are lost. There will be no more ReWo GH2 cages.

Do not like their bottom part, as if you mount it directly on QR plate contact space will be quite small due to cutouts.

Also no customized rods mount makes battery hole not very useful.