Underwater Bubble Blowers User Group Thread NEW

[Ron Lagerlof]

I have sort of settled on two lenses to start off, the Tokina 11-16 rectilinear and the Tokina 10-17 fisheye, both well known among underwater shooters.
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Again, suggestions in terms of lenses worthy of consideration or any other comments, ideas will be more than welcome.

Rudi, sounds like an ambitious project and I would be interested to see what you come up with. As you know, I love both lenses, but neither works at the full wide position. I could post a frame of the 10-17 wide open showing how much of the image it cuts off on the left and right. And the 11-16 cuts off the corners when using a diopter, so unless you can widen the outer element any other glass in front will likely have the same result. What would be awesome would be to get the 10-17 work first of all on a full frame (Nikon FX) sensor, and go from there...

Just my 2c. Ron

[Tom Hamilton]

Rudi, sign me up for the 11-16 optic.

[Johnny Friday]

Rudi,
The small OD....will this some how account for the gears and posts that gears sit on to protrude into the dome port area? seems at such a small OD, you run into a problem of HOW do you get posts, gears that sit outboard of the lenses to fit into the dome area in order to get proper placement of the lens behind the dome. But I'll assume you may have figured this out already. But i mention it since i recall having problems with a 6" dome port years ago not working with some gears i had modified for my AquaVideo housing and had to do some additional machining to get that to work....and in the end it seemed wider dome port would have to be necessary to fit with these new lens/gear configurations we are now using with DSLR or Video cams

[Johnny Friday]

Update: Sigma 15mm fisheye: now one of my go to lenses

shot on Epic at 5k; 2:1 @ 48fps @ 180shutter & a quick auto contrast/color in photoshop...also there is a lens correction filer in PS that you can use to make the image rectilinear. But to be honest....i like it "either" way. The fisheye effect is slightly noticeable in the background on the original shot but does not in any way bother me or my eye.




Image Link: http://www.flickr.com/photos/redcine...ream/lightbox/

[Rudi Herbert]

Ron,

I know the lenses vignette slightly on the Epic, that's why I'm taking down the 11-16 typical FOV of ~ 104 deg on a DX sensor to ~ 98 deg on the Epic, after accounting for loss of edge detail. On the 10-17, frankly, it doesn't much matter since you are starting with ~ 180 deg, so going down from there to ~ 150 deg, which is what I think it ends up yielding on the Epic, that's plenty wide anyway. In terms of adapting this lens for full frame or FX sensor, there are much better optics such as the aforementioned Nikon 14-24 and 16-35 lenses, both of which are made for FX sensors. I am trying to cater first and foremost to cinema applications, hence trying to suit the Epic sensor (don't much care for other cinema cameras, they are truly, secondary on my list) and second, trying to amortize costs by selling also to the photography crowd, since the large majority of them shoot DX/1.6 crop sensors instead of FX. But I think the 10-17 doesn't fit the FX sensor until about 13 mm or so, at which point, other lenses make far more sense.

Johnny,

Don't forget these domes are designed to "start" from the lens' front element forward, so behind that, you have all the space you need to run gears, actuators, levers and what not. that's part of the beauty of the design.

[Pawel Achtel]

DeepX article in June issue of Australian Cinematographer Magazine: http://achtel.com/News/AC%20June2012.pdf

[Tom Hamilton]

Well Johnny,

I think the art of shooting fisheye underwater involves framing subjects that take advantage of the corner sharpness, but only where it is not evident you are using a fisheye. Your sandy bottom in the lower portion of the frame has marked barrel distortion, disturbing, at least to my eye anyway, not too difficult to spot the lens type. If that's what the client wants, perfect. Just my opinion, you have the upper hand here.

I used the Sigma 15mm u/w at El Arco in Cabo a few months ago, sent it back afterwards to B&H for a few reasons, wasn't really happy with it. There are better f/e options out there.

Pretty shot btw, classic Friday!

[Johnny Friday]

Tom,
what lens is this? Is there obvious barrel distortion?
....as for the 15mm fisheye, i have to disagree. I think it's a strong lens. But as they say, beauty is in the eye of the producer.

[Pawel Achtel]

thanks Tom for nice comment.

Regarding fish-eye lenses, when used sparingly they can create pleasing effect. The most inspiring shots that I have seen were from David Hannan on Coral Sea Dreaming and Raptures. He used fish-eye to a great effect particularly on some schooling fish shots that do not have any reference to sea floor or other stationary subjects. However, I regard a fish-eye lens as specialty lens, not the main lens. It is about choices. There is a wonderful Sea&Sea 12mm fish-eye extreme wide angle lens that works very well on DeepX. But, for me, as a work horse lens, nothing beats the Nikonos 15mm: whether it is a sea dragon, a diver or a whale.

I think the main reason people so often resort to fish eye lenses with traditional systems is much simpler than "the beauty is in the eye of the producer". I think it is more of a necessity as they can not achieve good results with rectilinear lenses behind a dome port. I have not seen any footage or a frame grab shot with S35 or larger sensor and rectilinear land lens placed behind a port (either dome or flat) that would hold up on a large screen. This is also why many underwater film makers (Bob Cranston, David Hannan,...) still use 2/3" F900 HD cameras and produce better looking images than with RED One or Epic.

And it will get even more tricky with even larger Dragon sensor.

[Johnny Friday]

Here is Tokina 10-17 fisheye where you I dare say you can notice any curvature or distortion.



Image Link: http://www.flickr.com/photos/redcine...ream/lightbox/