GH1 Stereo 3D rig

Yeah, I've been doing 3d stills for ~20 yrs now. Not some hobbled together twined rig, but a purpose built Stereo Realist from the 50's.

I've toyed with twined video rigs - but man it's like bashing your head against the wall...

I'm gonna let Panny take the lead on this one. I'll jump in both feet once they get it down solid and easy, as I'm sure they will.
 
I wonder what is the closest distance that you can get the two lenses/bodies together? From what I've read, lenses should be 75mm apart or less (not greater than the separation of human eyes).

This is not entirely true. You can shoot with larger distance, but the closest subject should be further away (let's say at least 30-times more than separation of the lenses at 35mm/35mm equivalent lenses - so 17.5mm lenses on GH1). However, the subjects would look smaller.

You can make great hyper-stereo pictures/movies.
 
Also I am not ruling out a mirrored prism for two lenses on one camera, I have not done the exact math on the gh1 sensor size for putting two imagies on it just a rough est.

Easier solution would be to make a half-mirror rig. Then you would have adjustable base from 0cm (inches) up to.... whatever you like. However, you loose half of the light (1 stop).
 
genlocking the dslrs would be my concern.

Mine too. However, as it seems, it is not easy. There is a quartz inside and service manual does not cover the main board. However, temporary synch might be achieved. I'll probably do some tests in the near future.
 
I've just created a new thread on this topic, in the GH13 firmware hack sub-forum. We've had some limited success with a twin-GH1 mirrorbox rig and are interested in collaborating with other stereo enthusiasts.

David, I am not so sure that thread should be placed within GH1 Firmware Hack forum. I would rather choose "GH1 Hardware, Lenses, etc." forum. 3D does not have any direct relation to the hack, yet.

And, yes, I am interested in collaboration as well. :)
 
I actually bought two Panasonic TM700 camcorders to do 3D work...but after comparing the image quality with my hacked GH1's I've decided they are not worth the effort. So I'm back to base one. Not sure how two Gh1's would go with such a large inter-lens distance...my guess is that it might be OK...but the 3D effect will be magnified.

Why do you think that image quality of TM700 is not OK? I thought that sharpness on TM700 should be higher. With larger inter-lens distance you have to step back. With 20mm lenses (40mm equiv.) my guess is that the closest subject should be at least about 5m away. Otherwise you may experience pain in your eyes.

An important issue is lack of Genlock. I'm currently building a cable switch that will start/stop both cameras in "sync". I'm also hoping that shooting at higher fps will smooth out any slight sync variation (sound sync isn't an issue for what I shoot). I've read that there's software (Pluraleyes) that helps correct sync.

It won't help considerably. Any movement of the hand or falling leaves, moving cars, etc. will result in bad 3D. It depends on cameras missynch, anyway. 1/100s or 1/120s of a difference can be clearly noticed.

Depth of field needs to be as great as possible for the best 3D effect...otherwise it tends to look a bit like a kids pop-up book.
...
I suspect that soon Panasonic will have an affordable purpose built camera...not simply some ad-on lens but a consumerised version of the full HD 21k$ unit they are about to release.

I agree about depth-of-field. It's almost always good to have deep DOF. However, in some (limited) cases you can use shallower DOF as well.

Even if they make it, it will still have fixed stereo base (the distance between the lenses). So, better solution would be to make a camera with external genlock connector with all other signals (pre-trigger, shooting, movie button, menu, etc.).
 
David, I am not so sure that thread should be placed within GH1 Firmware Hack forum. I would rather choose "GH1 Hardware, Lenses, etc." forum. )

Good point. Do you happen to know if there is a process for moving a populated thread? There has already been some useful discussion there. Many of the points discussed above (e.g. inter-occular, sync) are being discussed there as well.
 
I just measured the distance...135mm. This is almost double the ideal interocular distance of about 70mm.

I think the application for a side-side GH1 rig will be pretty limited. There are some good mirrorbox rigs available off-the-shelf. We're using a 3DFilmFactory INDIE rig at the moment (http://www.3dfilmfactory.com/index.php?option=com_content&view=article&id=52&Itemid=76) and their MINI rig looks ideal.

Additionally, if we get sync working, Aquavideo has committed to building a very flexible GH1 rig. They are developing a mini mirrorbox that can fit into an underwater housing, on a shouldermount or on a steadycam mount. I'll ask Mike Hastings at AquaVideo to chime in and drop some details.
 
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