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Underwater Bubble Blowers User Group Thread NEW

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Beautiful. Looking at the back plate, have a very good idea of the size of the housing now, nice and compact.

Excellent work John and the Gates team!

Just a thought here, would be interesting to have a shock-absorption protective cradle that would allow the Epic to be transported inside the housing, the whole package sized in an airline carry-on friendly way.
 
How do you trigger the EPIC when in a housing

How do you trigger the EPIC when in a housing

Hi,

I have a custom U/W housing for the RED ONE that also works with the Alexa and Phantom cameras. I now would love to get an Epic running inside but have not really been following all the posts etc about the Epic. Can any of the underwateries tell me how do you trigger the Epic camera to record when in a housing? i.e. is there a little fischer/lemostyle connector or what? Also I think I heard that there were detailed size drawings for the Epic somewhere on the RED USER site. Is this correct? and if so can anyone point me in the right direction.

Thanks in advance.

Kind Regards


George Evatt
www.coralseatv.com
Sydney, Australia
 
Hey George,

Long time no hear.

I was going to give you a ring to catch up. There are several options for triggering, not as simple as Red One. But, the biggest problem currently is to power the camera on: there doesn't seem to be a way to do it remotely and requires pushing the side button. The word from RED is that they are looking itno it as this is a big limitation for any remote operation. Let's catch up, Ive got all the current info and drawings.
 
Question for you..I did 2 RED shoots underwater last 2 weeks using a standard 14 Zeiss pl lense....2 days ago I mounted the 14 zeiss as I always do and prefocused it on land with my large focus chart..went in the pool for the Tv shoot with 3 sets of kino flo underwater lights.I again checked prefocus on 2k at 100fps for up close drowning actor shot and could not focus this lense underwater.poked the lense above water it was in focus..so we switched over to optitek nikon promount with Tokinia 11-16,, .2,8 nikon mount lense and focus was perfect above and below water...Anyone had such a problem ...
Jim Kozmik IATSE 667 DOP..Canada
 
Can someone quickly tel me if there are closed circuit re-breather systems that let you blow zero bubbles? And are there "semi-closed" circuit re-breathers??

I've seen several videos where divers are using closed circuit re-breathers but they still where blowing (few) bubbles, even while staying at a fixed and very shallow depth.

Thank you.
 
jim kozmik said:
Question for you..I did 2 RED shoots underwater last 2 weeks using a standard 14 Zeiss pl lense....2 days ago I mounted the 14 zeiss as I always do and prefocused it on land with my large focus chart..went in the pool for the Tv shoot with 3 sets of kino flo underwater lights.I again checked prefocus on 2k at 100fps for up close drowning actor shot and could not focus this lense underwater.poked the lense above water it was in focus..so we switched over to optitek nikon promount with Tokinia 11-16,, .2,8 nikon mount lense and focus was perfect above and below water...Anyone had such a problem ...
Jim Kozmik IATSE 667 DOP..Canada
Click to expand...

Jim, this is normal, I'm surprised that you are asking the question. You would be focusing on a virtual image through a dome port. You can calculate the conversion between land and underwater. It is not a linear scale. You can read some basics of dome port on my website, here: http://achtel.com/Optics/
 
Roberto Lequeux said:
Can someone quickly tel me if there are closed circuit re-breather systems that let you blow zero bubbles? And are there "semi-closed" circuit re-breathers??

I've seen several videos where divers are using closed circuit re-breathers but they still where blowing (few) bubbles, even while staying at a fixed and very shallow depth.

Thank you.
Click to expand...

Roberto, semi closed rebreathers allow you to breathe fixed mix and release about 1/4 the volume each breath. Assentially you breather fixed % Nitorox and your PPO2 varies. Closed circuit rebreathers allow you to breathe variable mix with constant PPO2 and do not release any gas into the water except only to compensate for the volume change with depth change. I'm rushed to the beach ....so this simple explanation will have to do for the time being :)
 
Roberto Lequeux said:
Can someone quickly tel me if there are closed circuit re-breather systems that let you blow zero bubbles? And are there "semi-closed" circuit re-breathers??

I've seen several videos where divers are using closed circuit re-breathers but they still where blowing (few) bubbles, even while staying at a fixed and very shallow depth.

Thank you.
Click to expand...
Most closed circuit rebreathers will not blow bubbles if the operator is skilled at the use of the unit. However on ascent the closed circuit rebreather has to blow off the expanding gas in the counter lungs. There are many wonderful units manufactured in the USA. I personally use a ISC Megalodon as they are robust and have integrated Shearwater computer for efficient monitoring of decompression obligations etc.
 
I think the problem was.trying to shoot 2k on the RED at 100fps with a 14mm lense that compressed the image size and the f stop was set to low I think around F5.6..when we swapped lenses the tokinia 11-16 was set at F11 and was tac sharp in air and water..I will play with this...never done much with math underwater..kozz
 
jim kozmik said:
I think the problem was.trying to shoot 2k on the RED at 100fps with a 14mm lense that compressed the image size and the f stop was set to low I think around F5.6..when we swapped lenses the tokinia 11-16 was set at F11 and was tac sharp in air and water..I will play with this...never done much with math underwater..kozz
Click to expand...

Just guessing here Jim, but if it was a rez/f-stop/frame rate-, and not a focus issue, methinks you should have had the same result with both lenses? Please post test results when you've resolved (so to speak :smile5:) this.

Cheers.

Tom
 
For actual focus your lenses have to be able to focus down to around 11" for a 6" dome or 15" for the 8" dome. Dof can catch that sometimes and fool you.

There really are some fairly basic optical physics going on here - that can be easily calculated. If you don't try to get a bit of a handle on the principles, the testing can often create more confusion than it solves.
 
Tom, he is probably shooting with a dome considering it is a 14mm, so no magnification factor. :)

Jim,

Mike is correct. I did a simple Excel spreadsheet conversion table, taking account the size and thickness of the dome and focal length of the lens. It is very interesting to play around with it. Also used it to optimise my CinePort. Some lenses can't focus close enough and require a diopter. My CinePort, for example, is 12" and therefore causes relatively small curvature of field and virtual image is reasonably far away. Not all domes are created equal... :)
 
Can you post these charts for film lenses for me thanks..Jim Kozmik
 
Well Roberto.. we do breath air and it expands as we come up and we do vent underwater for over inflateing breathing bags..I have been using rebreathers for Ocean shooting for 11 years...I use now the last 4 years the Evolution with a travel pack and costumized to help me in deep cold dark Canadian waters as well..It is the best method for any underwater filming.You play dead on the bottom.fish love you..my whole underwater team is on rebreathers..shooting in a pool towards the surface..dead flat and also I can hear the director yelling at us underwater better on the hydrophone system...diving less than 20ft of water is always difficult with rebreathers..Kozzz
 
Hay Mike..do you have any conversion charts for PL film lenses..You going to DEMA..see you there..Kozz
 
jim kozmik said:
Can you post these charts for film lenses for me thanks..Jim Kozmik
Click to expand...

Jim, there are too many variables than the lens. You need to know the location of the entrance pupil of your lens. It is also a function of the shape of the dome too. I'm attaching sample focus calculations for CinePort (TM) and Master Prime 14mm lens. As you can see:

1. for a subject 50mm from the dome, the lens needs to be focused at 374.8mm from the image plane
2. for a subject 0.5m from the dome, the lens needs to be focused at 547.5mm from the image plane
3. for a subject 5m from the dome, the lens needs to be focused at 766.9mm from the image plane

You can see the conversion from actual image to virtual image position is non-linear and requires a close focusing ability of the lens.
If you like to know more you can contact me by email at pawel.achtel (at) 24x7.com.au
 

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Just got my email from RED that SN206's epic-x is almost on its way - so we are having a housing sale - this week only - 20% discount on new Epic housings and accessories. 25% discount on a demo PVC epic housing. 35% discount on demo RedOne housings.

Current introductory list price on Epic Housings:

PVC: $5795 $4636 this week only
Aluminum: $7895 $6316 this week only
Redmote underwater case $1295 $1036 this week only

8" Glass dome frontplate (option) Red1 or Epic $2395 30% disc $1676.5 this week only

Demo PVC Epic housing (the one in the pic and the .pdf press release) nicely configured for Focus optics Ruby 12-24 zoom, will work with other lenses. $4346.25 immediate delivery.
Demo Alum Epic housing (the one in the .pdf press release) nicely configured for Focus optics Ruby 12-24 zoom, will work with other lenses. $5921.25 immediate delivery.

Brief press release on the epic housings:

http://www.aquavideo.com/press/AquaVideoEpicUnderwaterPrRelease.pdf



Demo R1 housings $5K to $10K list depending on configuration (one is configured with Birger controller) less 35%
 

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Michael Hastings said:
Redmote underwater case $1295 $1036 this week only...
Click to expand...

Mike, Very interesting. Could you post detail pictures of the Redmote case? I think terrestial redusers would be also interested :)
 
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