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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

Ya, I saw that. Good news for us all indeed.

John J Ellerbrock said:
Possibly good news for bubble blowers.

http://www.reduser.net/forum/showthread.php?111400-Dragon-Flare
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Great photos John, thanks for sharing.

John J Ellerbrock said:
Peter Kragh shared these photos from a recent gig at the NBL. Peter specializes in time lapse underwater imaging. Take a look at his demo reel.

www.PeterKragh.com

http://peterkragh.com/timelapse.html

J-
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I would like to see that. <wink>

Rudi Herbert said:
Ias I told Jarred before, I will HAPPILY eat my wetsuit (a piece of it at least)
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sorry for kidnapping the thread but just wonder if you guys can give me a site/forum where used underwater housings can be found/posted as I'm getting an epic any day now and want to sell my 5D MkII housing. thanks so much.
you can pm me so we don't trash this thread. thanks again
uros
 
Hello Uros,

Wetpixel is one of the best places to sell your gear. (http://wetpixel.com/forums/index.php?showforum=6). Try eBay also.

If you're looking for an underwater housing for your Epic, I can assist. Send me a PM.

J-

Uros Zuraj said:
sorry for kidnapping the thread but just wonder if you guys can give me a site/forum where used underwater housings can be found/posted as I'm getting an epic any day now and want to sell my 5D MkII housing. thanks so much.
you can pm me so we don't trash this thread. thanks again
uros
Click to expand...
 
John J Ellerbrock said:
Peter Kragh shared these photos from a recent gig at the NBL. Peter specializes in time lapse underwater imaging. Take a look at his demo reel.

www.PeterKragh.com

http://peterkragh.com/timelapse.html

J-
Click to expand...

Cool stuff.

Back in the late 90s I built 7 underwater cameras that NASA used whenever an astronaut was in the water. These provided a live view of each astronaut to the surface crew, for both safety and training purposes.

The space suits are extremely positively buoyant so the astronauts are heavily weighted to make them neutral and they are lowered into the water by a crane. Obviously any kind of leak could quickly become disastrous so they always have a team of two safety divers and the live camera within a few feet of them.


Sorry for the crappy capture from a youtube video. You can also see the cameras in the first couple minutes of the Space Station 3d Imax movie.
 

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Nikon 14-24/2.8 doesn't accept front mounted filters, and as such we have never tested it with a close up lens. I've looked at some press in things, but they all cause vignetting at 14mm on full frame (but maybe not on the sensors discussed here).

From an edge sharpness perspective, Nikon 14-24/2.8 is one of the worst lenses I've ever used behind spherical dome ports. All of these things are relative... This is tested on full frame 35, so some of that smushiness will be outside the image circle of even dragon. The lens isn't that much worse that other 14mm lenses that are available (I've used Canon 14mm /2.8L II, Nikon 14 /2.8, Sigma /2.8, and Sigma /3.5). The corner sharpness improves as you stop down, as you get further from the subject, and with a bigger dome.

With all that said, I'll use it for versatility with big animals in blue water. The ultimate decision is left to the user, and I'd always suggest that they buy/rent and test these things for themselves. I would agree with Rudi that 10-24 /3.5-4.5 is sharper at 14mm in most situations that I've tested, but it is slower and might not cover your sensor.
 
Rudi Herbert said:
The sharpness drop off at the edges is just too drastic, not a gradual drop but a sudden, abrupt transition, so with a diopter you smooth that up somewhat. Yes, the lens already focuses close enough that, when I tested on a RED and Gates, I had to go back to the PE 486 which is the longest extender Gates has to bring the lens back from the front of the dome. And then, with the loss of FOV from the diopter and it being a 14mm already, well, not worth the pain for me. But then, the Tokina 11-16 behaves in almost the same way as far as I can see in particular when shooting at an angle from the subject. Which is why, there I go again, I use the nikon 10-24, which boasts the sharpest corners I've seen from any lens behind a dome.
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Rudi, what closeup lens did you test, how did you attach it, and did you happen to try it on a full frame dslr to see if there was any vignette?
 
Ryan,

I had somebody saw off the petals on the front of the lens and adapt a filter holder to the remaining metal, which can then take I think an 82 mm filter. I used a B&H diopter. I think I may have tested it on an old full frame body (on land) and did not see vignetting through the optical viewfinder, but I don't recall if it was a +2 or a +4, and I can't be sure if there was slight vignetting either. If there was, it was not pronounced. Interestingly, this lens works much better with my corrected dome prototype than any other dome I've seen, though it still exhibits aberrations but they are quite passable, like the Tokina 11-16. I'm really thinking about going back to drawing board with my engineers in Germany to repurpose my dome specifically for this lens because the Sony 4K full frame cinema camera should be released within the next 6 months...
 
Nikon 14-24 / Ruby 14-24

Nikon 14-24 / Ruby 14-24

Thank you all for comments on the Nikon 14-24 / Ruby 14-24.

J-
 
Mauricio Handler said:
Pricing, accessibility / availability aside- does anyone
have any opinion on this glass as a viable option? John E, Johnny F others?
Sorry- Arri site down for repairs so will not send you to those links...
Thoughts?

Specs
http://cinescopophilia.com/arri-ultra-wide-zoom-uwz-9-5-18t2-9-lens/


Youtube
https://www.youtube.com/watch?v=TW_5hHsQvqU
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Mauricio: Yes, here's my thoughts---i have feature folks that would love for me to use this glass and pay a nice renal fee for it. And, based on MFD it should work behind a dome. That said, took me a few days to hang up that idea..how many rentals to recoup i think something around 40k or 50k....i can't recall the actual street price, but it made the Arri 8r look like a deal as i recall....
Get one Mauricio so i can rent it from you.....
 
Johnny- My sentiments are the same- I was just questioning (definitely setting costs aside) the physical properties of this glass and seeing if it would indeed work for us uw.
I would love to see results! anyways- A man can dream....

Best- MH
 
Ditto Johnny's comments. Further, the specs give you an idea of compatibility, but the true nature of performance with a dome is only revealed by testing. Modern lens design changes the traditional thinking of dome/lens interaction.
 
A couple of things about this lens; fixed entrance pupil position throughout the entire zoom range, that is ideal for an underwater zoom behind a dome. Unfortunately, looking at the barrel markings, minimum focus distance is 1.2 meters/47.3 inches. If my math is correct, and I stand ready to be corrected, that isn't close enough to focus on the virtual image for most dome ports out there. Except maybe Pawel's Cineport.
 
No, no dome port in existence can let that lens focus without the help of heavy magnification, at which point, it is no longer a super wide zoom but a regular medium to wide lens. And it would still cost $45K, and it would still be super heavy and super long and require big port extenders to accommodate it, which would then result in an immense amount of drag underwater and positive buoyancy to compensate for...

I don't know, I understand the allure of these "professional" optics but I think the differences in optical quality they may bring over good photography lenses are so minimal as to be truly irrelevant. And I am the (not so) proud ex-owner of an Arri 8R, which I used underwater a grand total of 6 times, and took me 5 months and over $15K to get something manufactured that could accommodate it. That Nikon 14-24 we were just talking about can run circles around it in every department on land, as can the Nikon 10-24 underwater. Happiest day with that lens was when I sold it. But of course, when the name ARRI is brandied about, magic conjurations of unmatched image quality start floating in people's minds, and perception, whether true or not, is the hardest thing to overcome. But to each his own, with absolute respect.
 
I seem to recall someone mentioning Pawel's Cineport was effectively a slice of a larger dome, although that number was never released.

Re perception, Rudi, that metric is known in some circles as Net Promoter Score, companies like Google, Apple, Starbucks, and Virgin America have some of the consistently highest scores year after year. Perception yes, but based on a very solid product, I imagine where we are concerned, what we do underwater, companies like Red, Gates, Arri, Aquatica etc would likely score right at the top as well.
 
Tom Hamilton said:
A couple of things about this lens; fixed entrance pupil position throughout the entire zoom range, that is ideal for an underwater zoom behind a dome. Unfortunately, looking at the barrel markings, minimum focus distance is 1.2 meters/47.3 inches. If my math is correct, and I stand ready to be corrected, that isn't close enough to focus on the virtual image for most dome ports out there. Except maybe Pawel's Cineport.
Click to expand...

Tom, in the video you can see them rotating the focus ring and it gets to .7 meters before the shot cuts away - I suspect it probably goes to less than .6 meters. Also the lens is 13.3" to the pl mount so add 2" to the sensor and focus on something touching the front of the lens would be 15.3" - add 3.5" to the dome and 8" or so to the virtual image (approx 3 ft actual subject on an 8" dome) and you get to 26.8" so pretty close to even that .7 meter/27.3" mark.

All in all though it seems like a pretty unwieldy lens for underwater work. Would have to be really special to make it worthwhile.

PS a little searching turns up a close focus of .55 meters/21.6 " so focus shouldn't be a problem with an 8" dome.
 
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