GH1 Stereoscopic Rig Collaboration

I still hold that its more trouble to have auto iso. The light can change from one camera to the next. Then we have 2 images with a different brightness. Perhaps more noise in one. Remember that ISO is in discrete steps of 1/3 stop.
It makes sense to tie the iso function together.
Hmm.. Now I see why a MVC is so useful. You can have 2 cameras tied to a single PC, then you can control camera parameters via the PC.
With a servo zoom, even the zoom and iso functions can be fed automatically.
 
First test results!

GH1_rig_elephant.jpg


I'm ready to declare an initial victory with the GH13 stereoscopic camera rig. After considerable weekends and evenings spent bench testing and tweaking, I was actually able to get out and shoot over the weekend. The results aren’t bad. The critical problem of intermittent sync offset seems to be solved with manual lenses. There is still a LOT of work left to do to optimize quality and usability (e.g. tweaking the firmware hack parameters, building a better field monitor for alignment and exposure control, building a microprocessor-based controller with sync drift compensation…) and to make the project easier for others to duplicate.

Before all of that, however, I’ll be spending some time out shooting.

"Elephant in the Groove" test movie, shot with GH13 "C settings" AVCHD, Nikon 10-24mm w/ Iris-controlling adapter, can be downloaded here:

- 1080 Anaglyph Windows Media (VC-1): http://beampath3d.com/pub/Elephant_anaglyph_(med).wmv

- 720 Anaglyph M4V (H.264): http://beampath3d.com/pub/elephant_anaglyph(low).m4v

- 1080 Side-Side MP4 (H.264): http://beampath3d.com/pub/Elephant_side-side(h.264_med).mp4

- 1080 Side-Side Windows Media (VC-1): http://beampath3d.com/pub/Elephant_side-side(med).wmv
 
Another idea how to check synch

Another idea how to check synch

How about using this microCtrl setup:

- place a hole with a short pulse flash LED in the bottom black area of your rig
- when GH13 is powered up, also the µC system starts and immediately
sends a single flash on the LED
- two light traps with illumination sensors (PD) are attached to the viewfinders
and integrate the amount of light presented by the viewfinders
- The µC measures with two ADCs, compares both samples and decides whether
the synch is okay or not.
- if not, a red LED goes off
OR
- the cold start power up is controlled by the µC as well and is retried until
synch is established
 
pixelpartner said:
How about using this microCtrl setup:

- place a hole with a short pulse flash LED in the bottom black area of your rig
- when GH13 is powered up, also the µC system starts and immediately
sends a single flash on the LED
- two light traps with illumination sensors (PD) are attached to the viewfinders
and integrate the amount of light presented by the viewfinders
- The µC measures with two ADCs, compares both samples and decides whether
the synch is okay or not.
- if not, a red LED goes off
OR
- the cold start power up is controlled by the µC as well and is retried until
synch is established
Click to expand...

You don't have to do that. You can monitor composite video out signals all the time. However, according to David Cole, it doesn't have strong correlation to the actual synch between both cameras (when the actual frames are taken) when using auto lenses. However, with manual lenses, correlation is much higher.
 
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... initial victory with the GH13 stereoscopic camera rig
Click to expand...

Well done, I just watched the footage yesterday on my Alienware AW2310 Nvidia 3D Vision setup, and it looked really good. In particular I looked at the elephants fast moving trunk and tail at some parts of the video, and the sync just looks perfect. Now my questions is : " To wait or not to wait for the GH2 to be hacked and 3D sync ready ?"

Let's say I'd decide for the GH13. I think that there might be more people like me that enjoy shooting as well as editing 3D, are on a budget, but are no rocket scientists like some of you guys ( I mean it in a positive and respectful way, as it all is thanks to you guys ) and would be interensted in buying the final syncronizing machine, maybe even the full setup, of two GH1 with close manufactury numbers,hacked to GH13 with the sync machine and ready to go. At least I would be interested in such a deal, as at the moment even the Canon XF100 slaved to XF105 are still out of my budget, and cheapest sync and decent quality speaking, well they are the cheapest deal out there, while not being really cheap.

Anyone supporting my idea of this "Buy Now" product, write your thoughts or suggestions.
 
Dave, could elaborate the final rig of your 3D with the electronic curcuits?


So, now the problem is you can't zoom in and out in sync. And you have to manually adjust zoom if you want different zoom. How do you make the zoom exact same for both cam?

Actually, I own a Panny 3D TM700 which was just out. I got it before the official release 10/15, and the official one is TM750, but mine is "hacked one", if I can say so. And fuctions exact the same. I can confirm the the problem as mentioned here before ( I believe if you get a pancake 3d lens for the gh1 would be the same). First, horizontal rez would be half, but my motion would be better, bcz TM700 has 1080P/60 mode, which is nicer. The biggest problem is the zoom is fixed at about 11X, Panny did this because they want auto focaus adjustment to minimum (at 11x will have long field range of focus, or they don't want you mess up with their pro 3D series). Yes, you can zoom, but you know with two frame in same main lens, you are immediately out of para pictures, say, you get each frame a half face, one left, the other right half, that's done with your so called 3D.
 
Last thing,if anyone else interested in this, I might get you two hackable gh1(body only) at 1100, or one at 550, but maybe not same batch.
 
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So was this a "hey look what i can do" thread, or are you actually going to make any of this available to us?
 
Do you want an engraved invitation? I provided the schematics for my controller on 08-29-2010, post #15. As I stated clearly above, the synch issues using that setup seem to have been solved by using manual lenses (I'm not sure that anyone has replicated my results, however). There MAY be a more sophisticated controller in the future - but - as I have said in this thread - I'm going to shoot for a while and not test. My test procedure and equipment are detailed in post #24, from 08-30-2010, by the way.
 
Ok, so I see several people contribute to this project. Is that any of you can elaborate the whole rig set up in detail with electrnic diagram on the switch or so?
 
Nice comeback.
David Cole said:
Do you want an engraved invitation? I provided the schematics for my controller on 08-29-2010, post #15. As I stated clearly above, the synch issues using that setup seem to have been solved by using manual lenses (I'm not sure that anyone has replicated my results, however). There MAY be a more sophisticated controller in the future - but - as I have said in this thread - I'm going to shoot for a while and not test. My test procedure and equipment are detailed in post #24, from 08-30-2010, by the way.
Click to expand...
 
iWATCH3D said:
Let's say I'd decide for the GH13. I think that there might be more people like me that would be interested in buying two GH1 with close manufactury numbers,hacked to GH13.
Click to expand...
Is it strictly necessary?

Don't any serial numbers work in a way or another?
 
Regarding matched sets of GH1's with nearby serial numbers....

Im pretty sure just about any pair will work - however - the unknown is how quickly they will drift apart (as this is a factor of tolerances in the oscillator onboard). What I do is to power-cycle after every take, which resets the drift offset to zero. If you keep your takes short, any GH1 pairs that you have will almost certainly have acceptable synch. I'd go for it!

The synch check described in this thread will tell you quickly and certainly how your pair of cameras perform, and it's FREE if you have an old CRT laying around. If not, a fast camera flash will do the trick.
 
iWATCH3D said:
Well done, I just watched the footage yesterday on my Alienware AW2310 Nvidia 3D Vision setup, and it looked really good. In particular I looked at the elephants fast moving trunk and tail at some parts of the video, and the sync just looks perfect. Now my questions is : " To wait or not to wait for the GH2 to be hacked and 3D sync ready ?"

Let's say I'd decide for the GH13. I think that there might be more people like me that enjoy shooting as well as editing 3D, are on a budget, but are no rocket scientists like some of you guys ( I mean it in a positive and respectful way, as it all is thanks to you guys ) and would be interensted in buying the final syncronizing machine, maybe even the full setup, of two GH1 with close manufactury numbers,hacked to GH13 with the sync machine and ready to go. At least I would be interested in such a deal, as at the moment even the Canon XF100 slaved to XF105 are still out of my budget, and cheapest sync and decent quality speaking, well they are the cheapest deal out there, while not being really cheap.

Anyone supporting my idea of this "Buy Now" product, write your thoughts or suggestions.
Click to expand...
this would be a great idea!
 
Not sure on the GH2s. The same sync / record trick we use on the GH1s will work, however, we'll have to see if they power-up in sync and drift as little as the GH1s. I'll let you know as soon as I get my grubby mitts on a pair.

As for the HDMI recorder deck(s)... results will only be as good as the sync'ed signal that you feed in. Garbage sync in, garbage sync out.
 
David Cole said:
As for the HDMI recorder deck(s)... results will only be as good as the sync'ed signal that you feed in. Garbage sync in, garbage sync out.
Click to expand...
What exactly does it mean?

I'm sorry, I am not an english speaker. Not even techie guy. Is it easy? Is it not? Quite possible?
 
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