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ChipG
05-26-2009, 05:47 AM
I went ahead and pre orderd a 2nd GH1 to shoot in stereo 3D.

My Avid can edit stereo 3D so if figured why not, it'll be a fun learning experience & I have always wanted to try to shoot in stereo 3D. I know a DIT who does 3D stuff for hollywood feature films and he will be giving me pointers and tips along the way.

Does anyone here have any interest in shooting stereo 3D with the GH1 or other DSLR?

divide
05-26-2009, 06:22 AM
Keep in mind that you can't sync capture time, zoom and focus on the 2 cameras. It will be your own judgement.

TrueIndigo
05-26-2009, 10:25 AM
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).

ChipG
05-26-2009, 05:01 PM
Keep in mind that you can't sync capture time, zoom and focus on the 2 cameras. It will be your own judgement.


Correct, I know of others who have had really good success using a dvx & hvx for 3D stereo without gen synch.

ChipG
05-26-2009, 05:04 PM
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).

75mm is a good distance, at times a lttle closer together would be good. It depends on what your shooting.

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.

androoow
05-27-2009, 04:33 AM
how do u plan on presenting your 3d footage to others?? via the red and blue glasses ..cause i don't think that cuts it anymore and i thought the polarizing method is only possible via cinema projection????although this "NEW TECH" that James Cameron's using for AVATAR might be something.... new??? if its just polarizing lens on glasses in cinema..then.. . kinda so what??
anyway i am curious to know what methods are available to us mere mortals.

ChipG
05-27-2009, 04:51 AM
I'm not planning on presenting it to others on a large scale (I'll post some files for the few people who do have interest), they would have to have a 3D stereo polarize display to view it in 3D, there are several of them hitting the market now.

http://www.engadget.com/2008/06/06/philips-debuts-22-inch-auto-stereoscopic-3d-monitor/


http://www.consumerdepot.com/productstd.asp?id=17120B&referer=google


My post wasn't really ment to be a big deal it was more to see if anyone else had any interest in it for a hobby type project you know, for fun.

Lots of studios are moving over to 3D and Dreamworks is now shooting 3D for all thier movies for some time to come so I want to learn a little about constucting the rig, editing the footage and displaying it etc. to stay up with the current movie making techniques and lingo.

ChipG
05-27-2009, 04:53 AM
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).

I'm waiting for measurements but don't rule out that you can turn one camera upside down to get it closer to the other one and flip the image in post, you can also butt the camera's up together (bottom to bottom) then crop in post and rotate each image 90 degrees, one to the left and one to the right.

androoow
05-27-2009, 05:46 AM
those monitors look interesting..will have to do some research , ive messed about with creating 3d with 3ds max with different quality of results .. wonder how they do their voodoo ..

ChipG
05-27-2009, 06:19 AM
those monitors look interesting..will have to do some research , ive messed about with creating 3d with 3ds max with different quality of results .. wonder how they do their voodoo ..

What type of monitor did you use to view your 3d studio max 3d project?

j
05-27-2009, 06:31 AM
I just made the change from NTSC CRT to HD at home. There are a couple of flat screens that are 3d ready. I got a samsung 42" 3d ready for $699 at best buy.

ChipG
05-27-2009, 06:41 AM
I just made the change from NTSC CRT to HD at home. There are a couple of flat screens that are 3d ready. I got a samsung 42" 3d ready for $699 at best buy.

Geez, that is an awesome deal. I knew they had hit the retail outlets but I ddn't know they were that cheap. I'll buy one of those before I will buy the $799 computer 3d monitor.

Nitsuj
05-27-2009, 08:10 AM
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.

Please tell me you have an example of this you can show. Do we know of anything that will have two cameras shooting through one glass by using a rotating mirror? I have an idea about something and I am thinking this would be the only way to do it.

ChipG
05-27-2009, 09:15 AM
Please tell me you have an example of this you can show. Do we know of anything that will have two cameras shooting through one glass by using a rotating mirror? I have an idea about something and I am thinking this would be the only way to do it.

Interesting Idea but don't you need the spacial offset of the lenses to make the image 3D? A left & right like the eyes?

No I don't have anything to show yet, just a couple pics of other people rigs.

http://www.dvxuser6.com/uploaded/30752/1243440877.jpg
http://www.dvxuser6.com/uploaded/30752/1243440910.jpg
http://www.dvxuser6.com/uploaded/30752/1243440931.jpg

Nitsuj
05-27-2009, 10:59 AM
Oh yes you do need that offset. I am wanting to get two cameras with different exposures in one lens. You know... HDR stuff. It is the only way I can think of that would make it possible other than filters in post which isn't the same. I have been doing some research on it and there are some college students who have been working on that concept but nothing more about it other than a pdf document floating around.

The 3D is something to think about. Thanks for the pics.

el presidente
05-27-2009, 02:06 PM
I went to an exhibition at earls court in london earlier this year and saw a company demoing all this technology using what i think was 2 of those cheap canon 1080i cameras(hv10?). I put on the glasses to see on a 52inch screen some footage of london and it was AMAZING...I asked about sync problems and they said theyd overcome them with cheap cameras...not sure how but there was some button on the rig that did something to help the sync.

j
05-27-2009, 04:53 PM
I think that Loreo produces 2 side by side images.

j
05-27-2009, 04:54 PM
genlocking the dslrs would be my concern.

David Cole
08-29-2010, 10:49 AM
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.

Skeptikal
08-29-2010, 05:55 PM
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).


I just measured the distance...135mm. This is almost double the ideal interocular distance of about 70mm.

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.

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.

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.

3D panels are all the rage here in Australia at the moment. The quality of the 3D effect is very impressive and pricing is reasonable because of the marketing promos available.

Within a year or so every large LCD or Plasma panel/TV will be 3D capable since it's very straightforward tech for the manufacturers...basically a 200 Hz panel with synched LCD glasses.

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.

swyzlstyx
08-29-2010, 06:11 PM
.....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.

http://www.bhphotovideo.com/c/product/723055-REG/Panasonic_HDC_SDT750_HDC_SDT750_3D_Camcorder.html

j
08-29-2010, 07:32 PM
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.

crunchy
08-29-2010, 11:27 PM
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.

crunchy
08-29-2010, 11:30 PM
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).

crunchy
08-29-2010, 11:32 PM
Do we know of anything that will have two cameras shooting through one glass by using a rotating mirror?

I suppose you meant half-mirror?

crunchy
08-29-2010, 11:35 PM
I asked about sync problems and they said theyd overcome them with cheap cameras...not sure how but there was some button on the rig that did something to help the sync.
Probably they used LANC synchronizers (you can find LANC/ACC inputs on many Canon camcorders). I built one by myself some time ago. There are some details about my project:

http://dsc.ijs.si/3dlancmaster/

crunchy
08-29-2010, 11:38 PM
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.

crunchy
08-29-2010, 11:42 PM
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. :)

crunchy
08-29-2010, 11:57 PM
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 Cole
08-30-2010, 10:10 AM
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.

David Cole
08-30-2010, 10:18 AM
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.

David Cole
08-30-2010, 10:22 AM
...I'm currently building a cable switch that will start/stop both cameras in "sync"....

It would be great to share R&D on sync with you. Our efforts to date are outlined here: http://www.dvxuser.com/V6/showthread.php?t=221553

swyzlstyx
09-10-2010, 04:57 PM
Damn....just when I thought I was done buying crap for a while, there's a Lumix 3D lens coming...and now Vegas 10 with 3D editing is coming next month. It's going to be an expensive year for home video gear! :D

http://www.sonycreativesoftware.com/vegaspro10