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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

The Gentleman's Underwater Bubble Blower Thread

Johnny, Mike,

I would love it if the culprit was IR contamination, easy enough to just figure out a way to slap a hot mirror somewhere along the light path, but I must agree with Mike it doesn't seem likely. In fact, doesn't the MX OLPF have an IR filter built into it? All said, I am willing to test this out just for the heck of it, far too many times have I come across the old "that cannot definitely work that way" only to disprove the notion, even to my surprise. If you have suggestions about fitting a hot mirror to a lens or camera, let me know, if not I will figure it out.

How about UV contamination? Could we test it with just a regular UV filter attached to the lens? I will test this too.

The idea that the MX's OLPF is indeed red in color has some merit to it, for any non-reflective color coating will indeed filter away the opposite wavelengths of the color it has. It just is mind boggling that the Epic, being such a great camera in every other aspect, has these awful problems underwater. Which of course, it is a phenomena exacerbated by conditions found underwater but whatever anomalies create this also have to have some impact on the camera's performance on land. FWIW, RED cameras have always had the worst IR contamination of any other camera I've seen them matched against. FWIW also, RED footage is the least productive in terms of color correction flexibility of all my cameras, albeit the one with the highest resolution, but it is a VERY hard pill to swallow every time I compare RED footage against old F900 clips, even EX-1 stuff shot side by side.

And whether Pawel knows the cause of the problem, or how to fix it, it is so far irrelevant since he's keeping mum about it so us mortals with the lesser intellects are left to figure things out all by our lonesome selves. Which is a proposition I like just fine.
 
Rudi, I have night footage shot with UV lights with no filter if that would be of use?

Can see what solid UV does.
 
I don't want to discourage you guys from experimenting. Just the opposite. IR and UV tests are worthwhile and good education for all other reasons, so please don't feel discouraged to play with ideas. It's good fun.

This phenomenon is quite complex and stems from sensor design and quantum efficiency. It is not present in any 3 CCD camera. So, Rudi is right on the money with his observations: the footage from F900 would look prisitine with nice rich blues, vivid colours and high contrast in comparison.

I have discussed it with Jon Shaw and even he admitted "it was way beyond him".

Even if I disclosed what the issue is, it wouldn't help you much as the solution is even more challenging. The good news is that we have taken the problem seriously and spent enormous amount of effort and expense to investigate, reproduce in the lab, measure it and overcome. We will be announcing the solution shortly when we are ready (does it sound familiar?).

And, before you go and ask Graeme Nattress to fix it, there is nothing to fix as this phenomenon, unlike IR or UV contamination, is highly desirable in most other situations. It is just a bummer it is highly undesirable in most situations underwater.

Best fishes from sunny Tasmania!
 
You are such a tease Mr Achtel. Hopefully your solution and understanding of the physics may shed light (pardon the pun) on even more drastic problem of megenta hue and halos with the NEX FS 700/100 camcorders for UW footage. Scarlet and Epic exhibit the phenominum too but not as bad. My EX1R never had that problem and I guess it may be because of each colour has a sensor. This may sound silly but what if one use two scarlets with a beam splitter and record two color in one and single color with the other. Set interaxial at zero. Just thinking aloud.

cheers

David
 
Johnny, the isopropyl alcohol rinse is working like a charm on my dome. I've also been using it on my dome port , even more effective.

Thanks for that, incredibly cheap and effective prophylaxis against salt and mineral ingress.

Anyone who wants the goods on best u/w practices, all you need do is follow his thread.:cheers2:
 
Btw, I did something incredibly stupid yesterday, I feel the need to express it here.

Woke up early morning, but late, was in a rush, had to do a black shade calibration because of switching to HFR for some specific shots. Fresh battery, fresh media, housing good to go, boat picks me up, out to the free dive comp which is already in full swing, they rush me into the water for some record attempts by some world champs, power up, monitor comes to life, full dark, rotate the iris wheel, nothing, turn the the housing around and look into the dome port, mother of Jesus the feckin lens cap is still on from the black shade!

Please all, I require your ridicule, in the strongest of terms, embarrass me to the max, so I never, ever, ever, do that again!

:emote_headwall:
 
david cheung said:
... This may sound silly but what if one use two scarlets with a beam splitter and record two color in one and single color with the other. Set interaxial at zero. Just thinking aloud.
Click to expand...

Conceptually, this is not silly thought process. But, you shouldn't be looking for a solution without clearly understanding what it is that you are actually trying to fix. Where it fails is that you can't align them and assure thermal and mechanical stability to less than 1μ, which is what you will need to achieve. Why do you think they don't make S35 3-CCD or 3-CMOS sensors? It is very hard to align them. That would be your first problem, the second problem would be to actually not repeat what is acctually causing the issue in the first place. So, we end up where we started from, and that is to understand, reproduce and quantify this pehenomenon before we try to fix it.

I can believe NEX FS 700/100 exhibits similar behaviour and, I think, all CMOS sensors would exhibit this behaviour to various degree.

The best (and our long term) solution is to come up with entirely different sensor design that has all the benefits of CMOS design, yet does not exhibit this phenomenon. I think I may have a solution to this!

We have a mathematical model of such design and it looks very promising so far. Also, as an interesting benefit and perhaps interest to the entire film making industry, is substantially lower noise floor (particularily in blue channel) and significantly higher sensitivity compared with current crop of CMOS sensors. We are aiming for about 2 stops (400%) of increased DR, and in addition to the ability to produce vibrant, high contrast images in underwater environment - something current CMOS sensors can't really do.

Anyone interested in funding my new sensor development programme? :)
 
Tom Hamilton said:
Btw, I did something incredibly stupid yesterday, I feel the need to express it here.

Woke up early morning, but late, was in a rush, had to do a black shade calibration because of switching to HFR for some specific shots. Fresh battery, fresh media, housing good to go, boat picks me up, out to the free dive comp which is already in full swing, they rush me into the water for some record attempts by some world champs, power up, monitor comes to life, full dark, rotate the iris wheel, nothing, turn the the housing around and look into the dome port, mother of Jesus the feckin lens cap is still on from the black shade!

Please all, I require your ridicule, in the strongest of terms, embarrass me to the max, so I never, ever, ever, do that again!

:emote_headwall:
Click to expand...

I'd complain to the housing manufacturer for this design fault!

Embarrassing enough? LOL ;-)
 
Tom Hamilton said:
Thanks Pawel, I figured you'd be the first to respond, have you ever done anything daft in your life?
Click to expand...

I left the lens cap on in my HDCAM camera housing three times. :)
 
Tom Hamilton said:
Btw, I did something incredibly stupid yesterday, I feel the need to express it here.

Woke up early morning, but late, was in a rush, had to do a black shade calibration because of switching to HFR for some specific shots. Fresh battery, fresh media, housing good to go, boat picks me up, out to the free dive comp which is already in full swing, they rush me into the water for some record attempts by some world champs, power up, monitor comes to life, full dark, rotate the iris wheel, nothing, turn the the housing around and look into the dome port, mother of Jesus the feckin lens cap is still on from the black shade!

Please all, I require your ridicule, in the strongest of terms, embarrass me to the max, so I never, ever, ever, do that again!

:emote_headwall:
Click to expand...
Not too bad Tom.... thought you were going to say "no lens mounted" .... hahaha!
I once had a "No media attached" on my monitor when I pulled the record lever.... even HH did the same when we were in Indonesia :-)
I think everybody does "stupid" things like that.
That's why I now take a test-shot before the serious work starts!
 
Tom Hamilton said:
Btw, I did something incredibly stupid yesterday, I feel the need to express it here.

Woke up early morning, but late, was in a rush, had to do a black shade calibration because of switching to HFR for some specific shots. Fresh battery, fresh media, housing good to go, boat picks me up, out to the free dive comp which is already in full swing, they rush me into the water for some record attempts by some world champs, power up, monitor comes to life, full dark, rotate the iris wheel, nothing, turn the the housing around and look into the dome port, mother of Jesus the feckin lens cap is still on from the black shade!

Please all, I require your ridicule, in the strongest of terms, embarrass me to the max, so I never, ever, ever, do that again!

:emote_headwall:
Click to expand...
The worse thing I ever did was close the housing of my old 16mm ACL Eclair and capture a fly. I was shooting a drama and when we watched the rushes every other shot the fly would crawl over the inside of the dome port. Luckily we had enough coverage for the scene to work.
 
Tom Hamilton said:
Please all, I require your ridicule, in the strongest of terms, embarrass me to the max, so I never, ever, ever, do that again!

:emote_headwall:
Click to expand...

I jumped in without my monitor connected! That was stupid.. and I have done the Memory Card at home trick...

Michael Maes said:
That's why I now take a test-shot before the serious work starts!
Click to expand...

LOL you would think none of us were serious with this level of amateur hour ;-)
 
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Some gigs, guys, are just a real pleasure. Pro mermaid Linden Wolbert, we did a spot for the Marine Preservation Society today, thirty or so local elementary school kids were invited on a glass bottom boat tour. Linden and myself snuck out on our own boat, she slipped into the water and appeared suddenly, even through that thick glass and several meters of water, I could hear their insane screams of joy. Really touched my heart, wonderful stuff.
 

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New thread: What's the dumbest thing you've done with your camera.
(Not talking about all the dumb shit we do diving....)

Mine: Letting the boat leave the dock with my camera rig still on the dock. Two f'in dives without a camera - are you kidding me!!!
 
Ron, I hope the camera was still there when you came back :-)

I have left lens caps on, no media, no batteries, alas, all of it came to light while performing the pre-dive checkup, not while already in the water. My best woopsie though was going down on a deep wreck with two cameras and leaving one of them tied off to a railing on the ship together with a stage bottle while I went on filming the rest of the wreck, only to come back 30 minutes later to find nothing! I didn't check the integrity of the railing, and being very brittle, it broke off and fell to the sand taking the housing and tank with it, landing 50 ft deeper while I already had over 2 hours of deco awaiting me. I had to come back the next day and spent over 50 minutes of bottom time searching for the housing, did not find it. So I came back a third time armed with a metal detector and found the housing, already 6 inches under the sand, and a good 100 ft down from where it had fallen. The stage bottle was never found, so somewhere off the coast of Genova in Italy there is a nice 80% O2 blend waiting for some lucky user. Housing was intact (Gates) camera still had battery power, but the whole ordeal cost me more in boat trips and gasses than the camera was worth, just 'cause you know, we don't leave no housing behind :-)
 
Guilty of this also Ron.

Guilty of this also Ron.

Ron Lagerlof said:
New thread: What's the dumbest thing you've done with your camera.
(Not talking about all the dumb shit we do diving....)

Mine: Letting the boat leave the dock with my camera rig still on the dock. Two f'in dives without a camera - are you kidding me!!!
Click to expand...

I was just so busy loading all the other gear and bags I did the same thing, left the camera housing bag in the car. Then was busy talking with someone on the boat.

I didn't even dive, just sat on the boat, why dive without a camera, fortunately nothing that was a working gig.

Thankfully a nice calm relaxing day out on the water here.
 
OK, I just did the dumbest thing ever I guess...
Just back from our trip to Cat Island and wanted to give the Deep Epic a good rinse....
I filled the rinse tank with clean water and had the housing in it while doing so.
Suddenly I hear "big bells" and looked in the tank: I put it in without monitor so the big bulkhead was completely open!
Fortunately the camera was not in the housing....
 
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