Underwater

[Austin Meyers]

here is some underwater footage using the sony spk-hcb underwater housing, and the remote in a watertight bag.

everything was shot in 24p "P"mode AWB

http://file.meyersproduction.com/hv2...%20HD%206k.mov

as of 1:40 AM CST the file needs about 20 more minutes to upload. it's 74mb. just wanted to get this posted up before i hit the sack for the night.

[Glenn Thomas]

Interesting clip. The place too, as from the outside it looks like a big public swimming pool, but there's fish and wildlife under the water. Nice.

[Austin Meyers]

it's a very cool place... it's a huge natural spring, that has been made into a public swimming pool. it's completely untreated and actually is home to some protected salamanders. bartin springs in austin tx. worth checking out if you're ever in the austin area. also the water is 68F year round... so be warned.

[Adam Perry]

the video looks nice!

how did you get 1920x1080 footage instead of 1440x1080?

[Blake Calhoun]

Does the case allow you to control the camera easily since it's made my Sony and not Canon? You mention putting the remote in a water tight bag?

I have an underwater shot I am planning and am curious.

Thanks,
Blake

[Austin Meyers]

i export it as 1920x1080 square pixel aspect out of compressor, but from what i've read recently that's no better than 1440x1080 and actually creates a bigger file, i'm doing some testing now...

because it's a sony housing you can't use any of the built in controls, so i just use the remote in a bag, it's works fine underwater for start/stop/zoom. i also modified one of the trays that snap into the housing to better fit the hv20, but one of the stock trays will work, but it's a bit tight.

this thread has more on that...

http://www.dvinfo.net/conf/showthread.php?t=91813

[Blake Calhoun]

Thanks for the link. Stuff looks good!

[Blake Calhoun]

Austin,

Could you fit the HV20's wide angle adapter on the camera with this housing?

[Austin Meyers]

i don't think so... there's only about 5mm clearance in front and only an 1 in or 1.5 in the back. the spk-hcc might be able to house both...

[Ray Bell]

not sure as to why, but underwater setups have the wide angle lens on the outside of the housing... its so the wide angle lens cant see the inside of the housing........

[Blake Calhoun]

So you're saying the actual housing would have special space for the camera's wide angle lens?

i notice on the descriptions of the two sony housings at B&H that for "wide angle" they say "no".

[Ray Bell]

Hi Blake... I don't think the Sony brand of underwater housings support wide angle lenses...

Wide angle lenses for underwater are a special lens that work underwater and do not work on land.... this is due to the fact that when a lens is surrounded by water the lens itself is effected by the water magnification...

The water surrounds the lens and the water itself becomes a lens in itself...
thats why underwater housings have flat ports and dome ports... in the case of a dome port the lens and water represent a convex and a concave lens relationship... the relationship forms a virtual focus area in front of the camera.

some wide angle lenses for underwater work are made by ion....

[Ron Chau]

The Sony underwater housing is only meant for casual use at shallow depths of 17 feet or less.

If you are a diver, you will want something more serious that gives you access to more controls, lens options, deeper depths, etc.. These housings often cost as much if not more than the camcorder itself. But if you like to dive and you like to shoot video, it can be a very fun and rewarding hobby.

[Blake Calhoun]

Thanks for the info guys. I have two shots for a project that will be done in a pool at a depth of about 10 feet looking back up towards the top of the water. I'm just worried that the lens in the HV20 is not wide enough for the shot, but maybe it will be based on your info.

The Sony housing is cheap so I can buy it and test before the shoot. I've never done underwater shooting so it's new to me.

One other quick question, is there a general rule for light loss and water? How many stops will I have to compensate for or will I? I'm sure it depends on the clarity of the water, but I will be in a clear pool shooting at dusk with a 1200 watt HMI Par for lighting (hoping to achieve shafts of light coming into shot - a dream effect).

Thanks!

[Ray Bell]

Blake, the effect your asking about is called a sun burst... these types of shots are normally done at much deeper depths than a swimming pool and the ray effects are created due to material suspended in the water that breaks the sun into rays....

Shooting video from the bottom of the pool will capture items that are suspended over the pool... tree's, power lines, clouds, sun shine.. or what ever...

I don't know what is involved in your project but if you just need some footage to enhance some other footage you'll be shooting you might consider a canned product.... here is some footage that you can purchase for a underewater sun burst..

http://www.animationsforvideo.com/html/vol_4_p2.htm

I have no affiliation to these folks but they do have some nice products and aren't too expensive...

also to answer your question about light loss, in a pool at 10 feet you should not experience light loss.. the pool bottom itself will act as a source of illumination, reflecting the light