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#21 Barry C

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Posted 11 April 2016 - 09:11 PM

Hi Barry:  Thanks for your helpful answer!! I see above that you prefer to shoot in 2.7K in Protune mode with both medium (127 degree),   and wide ( 170degree)  FOV . After all the video you have taken in warm clear water what setting  give you the sharpest and best resolution video, and also which gives you the best 3D effect

when seen on the big screen. I have a 50in Panasonic that is my acid test. Do you ever shoot 1920x108060P in Protune?? I have a modified Gates Housing that I always shoot 1080P60 with a Panasonic triple chip camera and the results are excellent, however I have to do a bit of a run around using the program MuliAVCHD to process after rendering in Sony Vegas 10E so the footage can be seen as real 1080P60using the AVCHD 2.0 protocol. The newer Panasonic and Sony blue ray players accept this.

 

Regards Steve

IMO, 2.7K gives you the very best the 3+ Black has to offer.  I always end up rendering it as 1080 29.97p, however.  Downscaling the 2.7K I think gives a better result than shooting in 1080 natively.  In 2.7K, mode more of the sensor is used. It's really the sweet spot of these cameras. Again, just my opinion.  As for the 3D effect, this much depends on how you set up your shot.  The best 3D comes from distinct foreground, middle, & background elements. In order to get good negative parallax- aka popout- you need to have foreground elements at 4 feet or less from the port. This works very well for fish.  At over 4 feet, or so, you'll still get a very good sense of depth, kind of like looking out a window, but you won't get the popout type of 3D. Of course, you can't expect that in every scene anyway, nor should you.  You mentioned that you once tried a Sony TD10 but didn't like the narrow FOV.  My standard setup is the GPs mounted on a JVCTD1 housing.  The TD1 also has a very narrow FOV, but, when used well, can also have advantages. It's actually somewhat easier to get strong negative parallax with it than the wider FOV GPs.  But, the GP picture quality at that 2.7K mode runs circles around the JVC  and has a MUCH better dynamic range with far fewer clipped highlights as well as being progressive as oppossed to interlaced. (I'm not a big fan of interlaced) The other advantage to shooting at 2.7 is the cropping potential.  You can crop quite a bit and still come out with true 1080 res.  The only negative about shooting at that res is that when the files are paired- I use Edius as my NLE- the timeline really bogs down, so realtime smooth playback is just not in the cards.  But, its worth it and there are workarounds.



#22 Barry C

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Posted 11 April 2016 - 09:13 PM

GoPro made a red filter for the dual housing? I have not seen it before... Can u help to share the link..?

Here is a Amazon link to the filter.

 

http://www.amazon.co...dual red filter
 



#23 hellhole

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Posted 12 April 2016 - 06:34 AM

Here is a Amazon link to the filter.
 
http://www.amazon.co...dual red filter
 


Thanks

#24 Rockfish 770

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Posted 12 April 2016 - 01:41 PM

Hi; I cant find the direct Gopro link but there are actually two filters one a red filter for blue water and a Magenta one for green water , they can usually be seen offered  on Ebay...........Regards Steve



#25 Rockfish 770

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Posted 12 April 2016 - 01:56 PM

IMO, 2.7K gives you the very best the 3+ Black has to offer.  I always end up rendering it as 1080 29.97p, however.  Downscaling the 2.7K I think gives a better result than shooting in 1080 natively.  In 2.7K, mode more of the sensor is used. It's really the sweet spot of these cameras. Again, just my opinion.  As for the 3D effect, this much depends on how you set up your shot.  The best 3D comes from distinct foreground, middle, & background elements. In order to get good negative parallax- aka popout- you need to have foreground elements at 4 feet or less from the port. This works very well for fish.  At over 4 feet, or so, you'll still get a very good sense of depth, kind of like looking out a window, but you won't get the popout type of 3D. Of course, you can't expect that in every scene anyway, nor should you.  You mentioned that you once tried a Sony TD10 but didn't like the narrow FOV.  My standard setup is the GPs mounted on a JVCTD1 housing.  The TD1 also has a very narrow FOV, but, when used well, can also have advantages. It's actually somewhat easier to get strong negative parallax with it than the wider FOV GPs.  But, the GP picture quality at that 2.7K mode runs circles around the JVC  and has a MUCH better dynamic range with far fewer clipped highlights as well as being progressive as oppossed to interlaced. (I'm not a big fan of interlaced) The other advantage to shooting at 2.7 is the cropping potential.  You can crop quite a bit and still come out with true 1080 res.  The only negative about shooting at that res is that when the files are paired- I use Edius as my NLE- the timeline really bogs down, so realtime smooth playback is just not in the cards.  But, its worth it and there are workarounds.

Hi Barry : Thanks again for the info, it sounds like you have really done a lot of experimenting. I have read many totally conflicting reports about the way GoPro uses their sensors for 1080 and 2.7K recording and also for the change of field of View from 170 degrees to 120 degrees, do you see a better 3D effect with mid  or Wide (170 DEGREE) angle when shooting 3D or is the quality and effect the same , just a different perspective??     You have given me alot of impulse to try UW 3D again!!  Yesterday I bought a Dual 3 Gopro housing  and the red filter......... now I have to buy both the GOPro 3+ Blacks. Once I get them I'll have to try them out in a pool before our next dive trip!!! Regards Steve



#26 Barry C

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Posted 12 April 2016 - 05:27 PM

Hi Barry : Thanks again for the info, it sounds like you have really done a lot of experimenting. I have read many totally conflicting reports about the way GoPro uses their sensors for 1080 and 2.7K recording and also for the change of field of View from 170 degrees to 120 degrees, do you see a better 3D effect with mid  or Wide (170 DEGREE) angle when shooting 3D or is the quality and effect the same , just a different perspective??     You have given me alot of impulse to try UW 3D again!!  Yesterday I bought a Dual 3 Gopro housing  and the red filter......... now I have to buy both the GOPro 3+ Blacks. Once I get them I'll have to try them out in a pool before our next dive trip!!! Regards Steve

Steve, I'm not certain how you're defining "3D effect." Are you referring to negative parallax- aka popout, or the overall sense of depth of the scene, without regard to negative parallax? I find both medium FOV & wide FOV quite useful for underwater work. It just depends on the scene. For non UW work, I'm no fan of the wide FOV with its horrible barrel distortion- which, of course, can be corrected in post. I just don't have much use for it and ALL my non UW shooting is at medium FOV. That being said, underwater, the wide FOV is quite good and, due to the optical qualities of water, the view isn't as wide and the barrel distortion is almost non existant. In the Bahamas video I posted on Youtube, the entire second chapter- Shipwrecks- was shot at wide FOV. So, that might give you some idea of how it looks. As for negative parallax, again, you will need to be quite close to your subject, the wider you get. With wide FOV, perhaps 2 feet and less.

Regarding buying GP 3+ Blacks, I need to give you a heads up on this. I've found that a VERY HIGH percentage of late manufacturered cameras have vertical alignment issues. I actually had to send several back to Amazon. My first 4 cameras were purchased several months before they were discontinued and didn't have this issue. But, I assume these later ones, which were new, we're manufactured at the end of the product cycle. I also ran into a few instances of white balance disparities between 2 different cameras from this group- although this anomaly was less frequent than the vertical alignment issue. As for this problem, if someone was only using 1 camera, this wouldn't be a factor, but it is when paired with a second camera in the housing. Generally, this alignment can be corrected in post with stereoscopic adjustment tools, but check to see if this looks severe after you've paired the clips and put them on the timeline. Also, check your white balance to see if the cameras are consistant. In addition, check to make sure your lenses are both equally sharp, as I ran into one camera which was just slightly soft, when compared to the other camera. When underwater, you should shoot at WB raw, so this might not be an issue there, but could be for dryland use when you may want to use the auto WB.

Regards,
Barry

#27 Barry C

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Posted 12 April 2016 - 05:54 PM

Another thing to consider when shooting 3D- or 2D, for that matter- with the GP is stabilization. Shaky 3D doesn't look too swift. My way of minimizing it, in addition to VERY careful shooting, is to mount the GPs on the larger JVCTD1 housing. I recently designed and had a plastic house fabricate a stabilizer fin for stand alone use of the GP at times when I choose not to mount it on the TD1 housing. It looks kind of like a small diving fin with a large bottom vertical rudder. It, hopefully, will provide good stability for both vertical and lateral movement. I'll be testing it in Cozumel this summer. There are some really good software stabilization solutions, as well. But, it's best to try to get stable content and then fine tune in post. Anyway, give it some thought in advance.

Edited by Barry C, 12 April 2016 - 05:55 PM.


#28 hellhole

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Posted 13 April 2016 - 05:30 AM

I found this a while back when I first started. It is still available on the gopro support page.

Now that I know they have a filter for it.. I am quite excited to start again...

So glad that I have kept the 3+ black!!! Whooohooo

What is the optimal distance for 3D recording?

Where does it apply?

3D HERO SystemDual HERO System

Answer

For optimal 3D recording we recommend keeping your subject at least 3 feet from the camera when shooting in WVGA, 720p, and 720p, and 5 feet when shooting in 1080p.

Edited by hellhole, 13 April 2016 - 05:31 AM.


#29 Barry C

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Posted 13 April 2016 - 06:26 AM

As for optimal distance, that would depend on the subject matter and what you want to accomplish. It would also depend on the FOV you're shooting at. Additionally, IMO, all GP Dual content will require Y axis stereoscopic adjustment in post. What I mean is that Dual content is pushed quite deep into the window and will need to be brought forward which is generally accomplished by moving the horizontal Y axis slider to the right. I have found that when shooting underwater, and trying to get nearby swimming fish in negative parallax, you will need to be under 4 feet from them. There is no problem with the GP even shooting at under 1 foot when trying to achieve negative P. Furthermore, if necessary, you can always push the window back in post with a left stereoscopic Y axis move.

#30 hellhole

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Posted 13 April 2016 - 08:38 AM

Hm... Interesting.. We have to remember that their fact pages are be on land.

#31 Barry C

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Posted 13 April 2016 - 09:14 AM

Even on land, if you feel that negative parallax would be desirable- which it definitely isn't in many scenes- I think under 5 feet would be much better. I would suggest from under 1' to 3' for best results. Shooting with the GP Dual, whether in water or dry land, is interesting for 3D. I think it's ACTUAL TRUE 3D zone is probably out to about 75' at the most. However, due to its propensity to push the window quite far back, it gives the perception of depth out to infinity. Of course, the objects that far back aren't really in true 3D but will appear to be due to the window pushback effect. Forinstance, when I'm using it to shoot landscapes for my Yosemite Channel, I frame the shots so that there are distinct foreground and middle ground objects within 10 to 50 feet or so and by doing this, the far away mountains, etc., will seem to be carried into the actual 3D zone. I call this hybrid 3D. But, with this camera, it is quite effective. What's nice about this, is that it gives a pleasing 3D effect with landscape views which have both near and far elements. The advantage to this is that in order to shoot true 3D of a distant object, your interaxial- actual lens separation- would have to be 1 meter, or more. This creates problems for any objects that are closer than your distant subject as they will appear to be quite miniturized, like little toys. So, I find the GP with its somewhere around 33mm interaxial, seems to be kind of a sweet spot for most common 3D shooting situations.

If you want to see this type of effect, watch the May Lake 3D video on my Yosemite Channel which is linked to the Underwater 3D Channel. That video was shot entirely with the GP at 2.7K medium FOV.

Edited by Barry C, 13 April 2016 - 01:41 PM.


#32 hellhole

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Posted 13 April 2016 - 11:12 AM

So cool. This is some great info...I am going to dust of my dual again and start some filming!!!!

#33 Barry C

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Posted 13 April 2016 - 12:21 PM

Keep me posted:)

#34 Rockfish 770

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Posted 13 April 2016 - 09:54 PM

Steve, I'm not certain how you're defining "3D effect." Are you referring to negative parallax- aka popout, or the overall sense of depth of the scene, without regard to negative parallax? I find both medium FOV & wide FOV quite useful for underwater work. It just depends on the scene. For non UW work, I'm no fan of the wide FOV with its horrible barrel distortion- which, of course, can be corrected in post. I just don't have much use for it and ALL my non UW shooting is at medium FOV. That being said, underwater, the wide FOV is quite good and, due to the optical qualities of water, the view isn't as wide and the barrel distortion is almost non existant. In the Bahamas video I posted on Youtube, the entire second chapter- Shipwrecks- was shot at wide FOV. So, that might give you some idea of how it looks. As for negative parallax, again, you will need to be quite close to your subject, the wider you get. With wide FOV, perhaps 2 feet and less.

Regarding buying GP 3+ Blacks, I need to give you a heads up on this. I've found that a VERY HIGH percentage of late manufacturered cameras have vertical alignment issues. I actually had to send several back to Amazon. My first 4 cameras were purchased several months before they were discontinued and didn't have this issue. But, I assume these later ones, which were new, we're manufactured at the end of the product cycle. I also ran into a few instances of white balance disparities between 2 different cameras from this group- although this anomaly was less frequent than the vertical alignment issue. As for this problem, if someone was only using 1 camera, this wouldn't be a factor, but it is when paired with a second camera in the housing. Generally, this alignment can be corrected in post with stereoscopic adjustment tools, but check to see if this looks severe after you've paired the clips and put them on the timeline. Also, check your white balance to see if the cameras are consistant. In addition, check to make sure your lenses are both equally sharp, as I ran into one camera which was just slightly soft, when compared to the other camera. When underwater, you should shoot at WB raw, so this might not be an issue there, but could be for dryland use when you may want to use the auto WB.

Regards,
Barry

Hi Barry: Trying to define what is a good 3D effect is hard, I think it really depends on taste however I also like a bit of pop-out once in awhile, with my land 3D Im trying to aquire a mental library of whats really good and there are alot of variables to what makes a scene stunning aside from just the normal criteria, but I think reef scenics have tobe  just about perfect as long as your at the right place at the right time ,,,,,,,,,,,,,,not that easy in real life even for  2D video!!! Thanks also for all you recomendations on how to shoot good 3D UW, I can see it will also be a real challenge to master, I think maybe I'll start off with doing some shallow shoredives so there is no time preassure to be back on the boat plus Ill get the bright light from being close to the surface, after putting a red filter on and having a F2.8 lens on the GoPro I imagine the video falls apart fairly fast at depth, unless you have squeaky clean water and a cloudless day!

               Thanks also for the heads -up about the GoPro 3+ blacks , thats going tobe a challenge, I was planning to buy on Ebay, I may end up a major Gopro seller after all is said and done!! But at least you warned me , I will now know what to look for and not get too discouraged thinking it was a problem with the housing or just  not a worthwhile to continue on for lack of quality, Many thanks once again, you have been really helpful,    Sincerely Steve

P.S. I saw just a bit of your videothe shark scene was really nice at the beginning. I am having super slow internet now once it gets fixed I'll watch it all, can it be seen on a Panasonic or sony 3d TV?



#35 Barry C

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Posted 13 April 2016 - 10:22 PM

Steve, the GP holds up pretty well at depth. 50-80 feet are no problem as long as it's not a real cloudy day overhead. The water doesn't have to be perfectly clear either, but it certainly helps. Alot of these types of imperfections can be cleaned up nicely in post. The other cool thing about shooting 3D, is that backscatter- I'm not referring to the type caught in video lights which I never use- is actually your friend. It is often close to the camera in the negative parallax zone and helps create a good 3D effect.

As far as the best way to watch 3D Youtube and if you can on your TV, I just can't say, not being familiar with your setup. I do no know that it can be very inconsistant. The way I watch it is through my HTPC using Cyberlink Power DVD as a software player. Power DVD will only play 3D at 720p but it usually looks quite good. I think that HTML5 through a browser will also work, but I haven't messed with it much. Wish I could be more help.

Regarding buying 3+ Blacks, the main thing is to buy from somewhere that will accept returns without a lot of hassle. Hopefully, you won't have to return them, but you might. I actually had to return 6 of them to Amazon. If you get an older pair, not from last production run, you might do quite well. If the only problem is mild vertical lens alignment disparity and the WB and sharpness are otherwise consistant between the 2 cameras, you might want to just correct that in post, and put up with it. It's really a fairly simple correction. However, if there is severe misalignment, then I wouldn't put up with it.

#36 Rockfish 770

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Posted 14 April 2016 - 10:06 PM

Steve, the GP holds up pretty well at depth. 50-80 feet are no problem as long as it's not a real cloudy day overhead. The water doesn't have to be perfectly clear either, but it certainly helps. Alot of these types of imperfections can be cleaned up nicely in post. The other cool thing about shooting 3D, is that backscatter- I'm not referring to the type caught in video lights which I never use- is actually your friend. It is often close to the camera in the negative parallax zone and helps create a good 3D effect.

As far as the best way to watch 3D Youtube and if you can on your TV, I just can't say, not being familiar with your setup. I do no know that it can be very inconsistant. The way I watch it is through my HTPC using Cyberlink Power DVD as a software player. Power DVD will only play 3D at 720p but it usually looks quite good. I think that HTML5 through a browser will also work, but I haven't messed with it much. Wish I could be more help.

Regarding buying 3+ Blacks, the main thing is to buy from somewhere that will accept returns without a lot of hassle. Hopefully, you won't have to return them, but you might. I actually had to return 6 of them to Amazon. If you get an older pair, not from last production run, you might do quite well. If the only problem is mild vertical lens alignment disparity and the WB and sharpness are otherwise consistant between the 2 cameras, you might want to just correct that in post, and put up with it. It's really a fairly simple correction. However, if there is severe misalignment, then I wouldn't put up with it.

Hi Barry: Thats good to hear that you can use the the Dual GoPro set-up all the way down to 50-80 feet, thats actually amazing, I wonder if they just automatically raise the iso or gain-up, if there is such a thing as gain internally on these little cameras, they really are amazing to be able to do this.Next week Im going to the NAB show here in Vegas( I live here also, now) GoPro usually has a big exposition there I will ask them some of these more intricate questions,there should be someone there to answer.That will be interesting to see how your invention for a UW stabilizer will work this summer, I was  thinking of mounting it to my Gates housing or just taking it down solo and floating as still as possible as I film, plus also putting a small line level on it so the video is at least not tilted , thats the main reason I have never bought one the lack of a good LCD or Viewfinder. 

                Once Im able, Ill try to watch your videos, , I dont have a HTPC, usually I just  load what need watching on a Western digital Media player and most all formats work ....however I have never tried  3D You Tube videos , Ill let you know if they work, although with YouTube downressing and there compression, Im sure the video is FAR from the quality of your original edit. today I bought my first Gopro it was originally bought in Jan 2014!!! We shall see how it pairs with the next one!! Best Regards Steve



#37 Barry C

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Posted 15 April 2016 - 06:33 AM

On the Gopros in Protune mode, you have the option of setting the iso to auto with a max of 400, or a max of 1600. I use the max of 400 setting. Actually, when diving in a place with good sunlight and clear water, if you used the max 1600 setting, I would expect, even 100,' would be possible. However, you might have to do some denoising in post.

As for stabilization, I would strongly suggest you don't use it as a stand alone. I just don't think you'll be happy with it, since you sound like a perfectionist like I am about such things. Besides using the main housing for stability and LCD viewfinder alignment, there is another solution which I failed to mention when I wrote about my stabilizer fin. You need to buy a Gopro 4 Silver. It has a built in LCD. I had a very simple L shaped plastic mount made that attaches to the Dual housing with Velcro. It has a GP mount on top of it so that the GP Silver can mount to it. This allows you to use the Silvers viewfinder on top of the Dual. It works quite well!

Cheers!

#38 Rockfish 770

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Posted 16 April 2016 - 11:17 AM

Hi Barry: Thats really great that the GoPros have two range limits for the iso settings. I am a huge non-fan of high iso usually on my DSLR's my max is about 400 and usually 90% of the time I have the iso pegged at 100! Im a die-hard film guy and try to get it right the first time and with the best quality, without having to resort to excessive post work. UW video is a bit different from stills with all the water variables, clouds going over and changes in currents that really affect the quality of what we shoot in a large and uncontrollable way. That will be interesting to hear from you about your use of a GoPro Silver 4 as a monitor once you come back from your dive trip. Before you told me this I was thinking about using a 20mm Nikonos viewfinder . Both will probably work fairly well they just will need some  finetuning in the field. Have you ever taken the Gopro 3d housing down alone , that is, not fixed to your big housing? Is the video horrible like that?? 



#39 Barry C

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Posted 16 April 2016 - 05:25 PM

I've never used the Dual housing underwater as a stand alone and probably never will. I do, however, regularly use it as a stand alone on land, I've used it there with the 4 Silver mounted on top for the viewfinder as well as with an optical viewfinder I bought and made another plastic L bracket for so that it can be mounted on top. Both work quite well. Of course, I can't use the optical viewfinder underwater and will use the 4 Silver top mounted for that when I use it with the fin stabilizer. Again, if you're shooting underwater for things you really care about, I wouldn't recommend it stand alone. I just don't think you'll be happy. On land, I also don't use it while walking. I have a friend who recently started using it with a gimbal for that.

As for iso, I'm with you, 400 is my limit on these small sensor cameras. I recently bought a Sony A7S2 with full frame sensor for some high end motion controlled- non underwater- timelapse projects I'm planning. I'm getting really spoiled since it shoots squeaky clean up to iso 12800 and with quite usable- after some post corrections- content up to about iso 51000! Needless to say, I'm planning on doing a fair amount of astro timelapse and lowlight 4K video with it.

#40 Rockfish 770

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Posted 18 April 2016 - 10:54 AM

I've never used the Dual housing underwater as a stand alone and probably never will. I do, however, regularly use it as a stand alone on land, I've used it there with the 4 Silver mounted on top for the viewfinder as well as with an optical viewfinder I bought and made another plastic L bracket for so that it can be mounted on top. Both work quite well. Of course, I can't use the optical viewfinder underwater and will use the 4 Silver top mounted for that when I use it with the fin stabilizer. Again, if you're shooting underwater for things you really care about, I wouldn't recommend it stand alone. I just don't think you'll be happy. On land, I also don't use it while walking. I have a friend who recently started using it with a gimbal for that.

As for iso, I'm with you, 400 is my limit on these small sensor cameras. I recently bought a Sony A7S2 with full frame sensor for some high end motion controlled- non underwater- timelapse projects I'm planning. I'm getting really spoiled since it shoots squeaky clean up to iso 12800 and with quite usable- after some post corrections- content up to about iso 51000! Needless to say, I'm planning on doing a fair amount of astro timelapse and lowlight 4K video with it.

Hi Barry: Thnaks for the advise on how you think would be best to use the Gopro 3D UW, without a doubt using the Gopro silver 4 as a monitor will be best for framing the scene and getting some really nice footage. The lack of a good viewfinder is without a doubt the Gopros weakest link, I have been shown umpteen shots of UW Gopro footage thats completely forgettable for lack of being able to frame the shot well. I think to begin with I am going to mount it on the my Gates  housing, I have used housings that are light , small, mid weight and heavy and there is something to said for a lot of mass in giving stability for really smooth video if your movimg either finning or going with the current. When I here about how your fin invention turns out, if your really happy with it , I may change. Water does help in smoothing things out. The Sony TD-10 I use has great image stabilization, however on land several times I have shot the same scene hand held and also on a tripod and the results are MUCH  BETTER on a tripod, actually I have quit shooting hand held because the loss in quality is that much. Shooting the same camera in 2D the results are great hand held!! Just the slightest bit of degradation in the 3D footage makes the results on the big screen a lot less nice. 

                The Sony A7 you bought will be a real adventure to use, they are extraordinary!!! The sensors they have are almost like science fiction, it makes you think ............what will we have in 4-5 years time. Are you also into Astrophotography with telescopes?? Best Regards , Steve