If you're shooting video with the Panasonic GH3, I highly advise you take a look at the Fhugen GH3 Video Cage. It's compact enough that you can leave your camera in there the entire time, and will give you more mounting points for adding on those necessary accessories. One question that comes up often is 'How do you add rails to the Fhugen Cage?'.
Although there isn't a dedicated 15mm rod adapter for the cage, the design is straight forward much like the tripod mount under your camera. You can mount it to a variety of baseplates that support 15mm rails (and yes it will be optically centered).
In the example above i'm using the PNCGear MP-2 dual rod baseplate (found here). There are height adjustments on the MP-2 if you need to make your rails slightly higher or lower. The baseplate can be used in any direction, but here I have the logo on the side of the LCD screen. Under the baseplate is enough tripod mounts to add your quick release plate of choice for tripod mounting.
I just ran into this auction for a used REWO GH2 Specific Video Cage. I'm sure someone out there might find this useful. This is a great product, but typically priced in the $400 dollar range. EOSHD has a nice write up about this cage (found here).
The REWO cage allows you to mount several accessories to the body of a GH2, and will clamp 15mm rails if you plan to use a Follow Focus or other 15mm accessory. I'm curious if it could work well to fit a Sony NEX, OM-D, Sony RX1, or other similar small body HD camera. I doubt it could fit the new and slightly larger GH3. The current price (as of writing) is set to $82 US dollars. Check out the auction following the link (click here).
Here's a simple DIY way to add an HDMI Cable Pinch to one of those Gini Panasonic GH2 Video Cages [Thanks Asa]. You could use this same technique on any of the other cages offered by Gini, and I just noticed that Gini is also offering a specific cage for the Canon 5D Mark III if you need all of those mounting points. Check out the Gini gear on eBay (Click Here).
Here's a (fairly lengthy) look at the Gini Rigs GH2 cage that provides all the cut outs to view controls and still have access to different ports around the camera. It looks like it's cut out to allow the LCD to still swing out also. No doubt it's high quality stuff, but there's been mixed complaints about the threading used on these cages as they may not be 1/4x20 accessible, but looking through the top area of the cage there seems to be different sized holes and threads. Maybe the new cages are supporting 1/4x20?
Still waiting to hear back from YouTube member feha1000 about that question, or if anyone else can chime in about a recent Gini Cage purchase. [Update] Here's the reply:
About 20 1/4" threads are on the top plate only the res M5 threads , and yes they work well with friction arms
The new PNC grips are on the way and should be added to the product line hopefully in about a week. Another product that's been in the works are a few different DSLR cages. The goal is to be the most affordable cage on the market, have excellent build quality, and offer a few varieties in size.
Seen in the (discreet) images above is the GH2 mounted inside one of the cages. The new DSLR cages I helped designed for PhotographyandCinema.com is pretty much hammered out in the production process and should be available in the coming weeks. Follow me on Twitter for more of these updates.
We finally get to see a video review of the ALZO Transformer DSLR Rig Accessory Cage. If you've collected quite a bit of external accessories, a cage is a simple way to keep things together while moving your about. Vimeo member Brian Russell shows how it's in use with a JuicedLink DT454 and an external Monitor. The handles of a cage aid in stabilization when going hand held, and not seen in the video could be the optional top handle from Alzo if you need to shoot low. The Alzo cages are available on Amazon (click here).