Underwater Bubble Blowin' Users Group

[chuck colburn]

Get someone to put an Olympus mount on your Red and you can use some of the finest still camera optics ever made. Including this little ditty.

http://www.adorama.com/IOM714.html

 

[Michael Hastings]

The Olympus e sensor is 18 x 13.5 mm so would probably have the vignetting issue - also it seems to only have internal iris control like the other digital specific lenses.

Get someone to put an Olympus mount on your Red and you can use some of the finest still camera optics ever made. Including this little ditty.

http://www.adorama.com/IOM714.html

 

[chuck colburn]

The Olympus e sensor is 18 x 13.5 mm so would probably have the vignetting issue - also it seems to only have internal iris control like the other digital specific lenses.

Ahh I see. Should have read up on that 4/3 sensor size!

 

[Michael Hastings]

RE: Canon EF-S 10-22 and Birger engineering mounts.

RE: Canon EF-S 10-22 and Birger engineering mounts.

There has been some info in the lens section about a mount for the EF lenses. I posted this over there, but think it has relevance here too.

I have a strong interest in this sort of thing for use in making the underwater housing for the RED. We have a compact board with an onboard micro controller that we use to do focus, iris, etc. through LAN C that I believe could be easily reprogrammed to send whatever RS232 commands the birger adapter needs. It seems to me that with what they have done already and if RED will give us the information on the front plate of the camera and flange distances to the sensor it wouldn't be that hard to do the physical part either. It seems like the RED team should be seriously considering the utility of the EF setup as it seems like the Iris is easier to do on the canon EF than the Nikon system. Also, it seems like the EF-S 10-22 would be a possibility since the sensor size is almost identical and it would provide the phenomenal wide angle zoom that I think a lot of us are looking for - but particular us underwater guys. We have a CNC machining center, so if RED is overloaded, with a little help we could do it here.

The Guys at Birger Engineering are looking into this. They have an intelligent adapter which allows control of EF mount lenses, but it currently requires a computer to be connected to it for communication with the lens. http://www.birger.com/Merchant2/merchant.mvc?Screen=ef232_home

There has been an amount of discussion about repurposing this technology to make a RedOne mount for EF lenses which would have a separate hardware controller, could be wired or wireless. This would allow for focus as well as iris control and it could be configured to act as a very effective follow focus. The mechanical action of the focus ring on the lens could be remapped to allow for much more effective manual control than could be executed with the focus ring. Parts of the focus range could be expanded, preset focus points could be assigned to buttons... lots of potentiol.

This is all exciting stuff, but still vapourware at the moment, however Birger have suggested that there may be an announcement coming up to NAB. I have attached a quote from a post by Erik at Birger which comes from the "Spike Black... First Prototype photos" sticky on the Red One forum.

Martin

Just remembered that the 12-24 has no iris ring - a bit of a problem with the RED. Anybody know if you can dig into these lenses to hot wire the iris motor? - we've done it many times with video lenses and it sure would make external control easier than with gears.

 

[David Nardini]

... the EF-S 10-22 would be a possibility since the sensor size is almost identical and it would provide the phenomenal wide angle zoom that I think a lot of us are looking for - but particular us underwater guys. We have a CNC machining center, so if RED is overloaded, with a little help we could do it here. ...

Yep AquaVideoRed206 ... great lens if somebody could give us an aperture control mechanism :w00t:

The Birger Engineering folk appear to be working on an EOS adapter, so fingers crossed, we'll end up with a wider pick list than just the older style (aperture control) lenses.
Have not seen this lens on their 'list', but I assume the protocol is the same for all EOS lenses ?

 

[Ken Corben]

AquaVideoRed206...

EOS adapter with LANC control for the Canon 10-22mm sounds like the slickest lens solution I have heard. Would you "CNC" a canon front plate for the red camera? That would be far more elegant than other work arounds.

Are you planning on RED PVC and plastic or glass dome for the housing design?

Sharky

PS- If you would share your expertise on the pros and cons of plastic vs glass domes for a hypothetical Canon 10-22mm underwater that would be much appreciated. "Explain it to me as if I were a six year old," from Denzel Washington in Philidelphia.

 

[David Nardini]

... If you would share your expertise on the pros and cons of plastic vs glass domes for a hypothetical Canon 10-22mm underwater ...

Not quite an explanation for 6 year olds, but here is a starting point :

http://scubageek.com/articles/wwwdome.html

Plastic is great in that you can polish off small scratches (eg: t-cut) ... glass you are pretty much stuck with it, but underwater you will hard pressed to see their effects. For split level shots, however, you may see the defects clearly (stopped down & close focus) ... depends of the shot.

An excellent (old but still good) reference book is 'The Manual of Underwater Photography' by T. Glover, G.E. Hardwood and J.N. Lythgoe (Academic Press). Not sure if it's in publication ... worth picking up an old copy.

The thing I don't like about domes is the curved depth of field they inherently exhibit. I much prefer Ivanoff ports (they also work better in air & for split levels). I'm trying to find somebody (?) who can machine / polish one up :help:

I've got the formula somewhere ... once I find it (Ivanoff port + corrective diopter pair) I'll post it ...

 

[chuck colburn]

David,

There are lots of sites for surplus optics (windows, lenses etc.) out there.
Some with anti-relective coatings already applied. These could save you a bundle over having one generated and coated. Do you have an idea of how large of one you would need. I like to poke around at these sites and might stumble onto one that would serve your porpise. hehe

Chuck

 

[David Nardini]

Ivanoff-Rebikoff u/w correction approach

Ivanoff-Rebikoff u/w correction approach

... Do you have an idea of how large of one you would need ...

Below is a picture summarising the Ivanoff-Rebikoff correction lens and some formulas ... hope I've not made a typo !
Essentially it's a reversed Galilean telescope in which the front (plano) concave lens is used for the watertight window. The lens system will be afocal if :
fd = fn + d
where :
fd = focal length of the positive lens
fn = focal length of the negative lens
d = separation between the lenses

In summary, the main benefits of this port system (as can be found on the Hassy SWC housing) :

• it is afocal and can be used in conjunction with a conventional camera lens of any focal length as long as it does not vignette the corners
• the focal length and field of view of the camera lens are the same in water as in air
• pincushion distortion, chromatic aberration and other aberrations of a plane (flat) port are corrected
• depth of field is increased by about a factor of 2 over a plane port with the same camera lens and aperture

Alignment of the optical axis of camera lens and correcting lenses (+ve and -ve) is critical. Ideally, they should all be mounted on one rigid mechanical unit (any flexing of the u/w housing under pressure will not affect quality; this is clearly only an issue for deeper work).

That's it :biggrin: anybody out there that can machine up / polish a perpex port for me :help: (I can sort out the +ve diopter). The underwater community could really do with a supplier of these ports ... !

EDIT : oh ... forgot to say, I don't know how zoom lenses will stack up in this scenario, but will find try and find out ...

 

[Mark Thorpe]

This thread is really coming into its own. A lot of information from a lot of talented people. Let's keep it going. I too am wondering what we will all end up with. David I'm hoping it will become possible to use the SWP44 but I think we are all starting to look at avenues that point to other glass options. I really do like this lens. The following is a shot from about 1 ft from the subject. Great coverage I reckon.

Cheers,
Mark

 

[Ken Corben]

Perpex Port - Sherlock Holmes is in the house...

Perpex Port - Sherlock Holmes is in the house...

David,

Thanks for the brilliant post on perpex ports and other ports- very intriguing!

Here's a lead - your looking for a guy named Warren Williams. This bloke worked on the original HASSY housings. I believe that Dr. Mustard (a friend of the Beatles?) has William's contact info and he is in your neck of the woods. Ring him and let us know what you discover.

Dr Alexander T. Mustard
Email: alex@amustard.com
Phone: +44 (0) 7876 523 110

Sharky

BTW - is this what the port looks like?

 

[David Nardini]

Swp44

Swp44

... David I'm hoping it will become possible to use the SWP44 but I think we are all starting to look at avenues that point to other glass options. I really do like this lens ...

Hi Mark,

As you own one of these, I'D HANG ON TO IT ! The reconditioned unit I was going to try and test tomorrow has been sold ... arghhh :angry03:
Brand new they are not a cheap item, BUT if they perform as good as suggested, then I'd be thinking of holding onto to it until you can test it on the RED (the only REAL way you will get confirmation).

I've asked a few folk here in UK to see if I can test against their unit ...

In the mean time (as you can tell) I'm also trying to source an Ivanoff port or somebody who can make me one ... given that the Nikkor 17-35/2.8 does not change in size during focusing / zooming I'm hoping that it should work ok.
Aim is for a port that covers up to 90 FOV (gut feel tells me that beyond this the port will become quite large).

There are plenty of dome ports suppliers, glass or perspex ... this is the simple and 3rd choice.

Another alternative is to jump on a plane and do a week in Palau ... now THAT would be too nice :w00t: (& pigs will fly too !)

The hunt continues ... (having said all this, if you really want to shift your SWP44 => let me know !).

 

[David Nardini]

David,

Thanks for the brilliant post on perpex ports and other ports- very intriguing!

Here's a lead - your looking for a guy named Warren Williams. This bloke worked on the original HASSY housings. I believe that Dr. Mustard (a friend of the Beatles?) has William's contact info and he is in your neck of the woods. Ring him and let us know what you discover.

Dr Alexander T. Mustard
Email: alex@amustard.com
Phone: +44 (0) 7876 523 110

Sharky

BTW - is this what the port looks like?

Hi Sharky,

I know Warren Williams VERY well ... he does all my custom dome ports, but NOT Ivanoffs !

I know of Alex Mustard, but never met him or spoken with him (he's only a few miles up the road in Southampton as it happens).
Yes, that lovely piece of glass on the front of that Hassy SC housing is a matched Ivanoff (positive diopter is screwed to the front of the lens) for the Biogon 38mm. Used to have one of these ... they are a LOVELY piece of (glass) optics ... I now wished I had not parted with it ...

I've emailed Peter Scoones to try and dig deeper on the Ivanoff story ... hopefully he can shed some light on how best to get one machined up. He's a busy man, but I'm hoping to speak with him soon.

I'm researching as fast as I can and will report back.

EDIT 1 : the housing you show is a 500CM unit ... just noticed the optical viewfinder at the back of the housing; the SWC has no reflex and the housing is a range-finder affair (not SLR essentially).

EDIT 2 : just spoken with Alex Mustard and I'll do some tests in March using his Hassy Ivanoff port and will report back. I'm planning on testing against the Nikkor 17-35/2.8 for the moment ;-) & they'll be land tests for the moment.

 

[Ken Corben]

David cheers mate...that's pushing the envelope with the Hassy to Nikon 17-35mm test - I love it.

Thank You for sharing

 

[Andrew M.]

Cam Diver what will be your pick for housing ?
Did you make up your mind yet?
Andrew

 

[Ken Corben]

What frame rate?

What frame rate?

What frame rate are you guys thinking for underwater?

4K or 2K?

 

[Mark Thorpe]

Cam Diver what will be your pick for housing ?
Did you make up your mind yet?
Andrew

Gates, seems to be the best way to go IMHO for my applications and working style. I am not pushing anyone to follow suit but I have worked with, still do, these housings and seeing as I work completely manual they suit me down to the ground. Bullet proof, proven track record and basically an all round solid deal. Great customer care and real people at the end of the telephone line. I had a problem with an external monitor here in Palau recently and they phoned me up to arrange replacements etc. How often you see that happening elsewhere???

As their logo says "Don't take a chance, take a Gates".

Cheers,
Mark.

 

[Mark Thorpe]

Hey Guys,
Looks like "Evin the Great" has come up with the long awaited report for the Nikkor 17/35mm. Looks like we have the work horse lens sussed. Now for SWA and a super macro option.

Cheers,
Mark.

 

[Andrew M.]

As their logo says "Don't take a chance, take a Gates".
Mark.

Mark, thanks!
http://www.gateshousings.com/XLH1.html
Looks great.

I am monitoring this thread for some time with high interest, though, if I take RED underwater it will be purely private event, nothing to do with professional activity. Hey!, all my business started like this

Any idea what budget, one have to have, to take RED underwater and have comfortable good equipment?
Excluding camera and lens, just underwater specific.
I love cave diving so good light is a must I think?
Andrew

 

[Michael Hastings]

Notes on the 17/35, other lenses, domes, Ivanoffs, etc.

Notes on the 17/35, other lenses, domes, Ivanoffs, etc.

Just a couple of comments:

1) As far as the 17/35 being the workhorse - I would question that, as 17 isn't really very wide when used on the RED - at the wide side it is roughly equivalent to 25-26mm on a 35mm still SLR, and covers about 80 degrees diagonal - not very wide for underwater work where the lens we are normally using for Broadcast cameras like the Panasonic VARICAM, Sony F900, etc. would be the Fujinon 4.5-59mm. It is about 107.5 degrees diagonal. For the RED we need to get down to about 10 or 11 mm to get the same wide angle (which is why I have been asking about using the Canon 10-22 EF-S lens or Nikon 12-24 on the RED).

107.5mm is really wide, but even with prosumer cameras like the Sony Z1 - most of the housing/lens combos can get you to somewhere between 90 and 100 degrees - much wider than the 80 degrees of the 17mm.

2) Regarding the Ivanoff corrector, first of all nice posts. We have companies in China that will grind either glass domes or Ivanoff type lenses at relatively modest cost if we order 20-25 units (the end user cost would probably be in the $2500 - $6000 range depending on the size). The question is whether it is really necessary, particularly right off the bat. If you look at virtually all of the housings for Broadcast cameras, 35mm cine cameras, IMAX, etc. - by any of the manufacturers, AquaVideo (my company), Hydroflex, Pace, etc. - they all use domes and most are acrylic domes. The reason is that they work very well both optically and from a practical engineering standpoint. We make our own domes for most of the consumer and prosumer HDV camera housings, but we often use Aquatica ports on our broadcast housings because they are well made, have off the shelf flat ports for macro available as well as extension rings that allow some flexibility for different lenses, and aren't overly expensive.

For the RED I would initially look at using the Aquatica ports or possibly even Ikelite ports which would allow greater flexibility with different lenses (we can't use the Ikelite with the broadcast lenses as they are physically too small, but many of the lenses we are talking about using for the RED would work fine with the Ikelite size port. (The Ikelite interchangeable ports are only 84mm inside diameter at the base so we can't use the broadcast lenses which are typically 95mm or more at the front.)

I also mentioned in an earlier post the possibility of actually making the front of the housing the front plate of the RED and incorporating a Nikonos mount which would allow use of the Nikonos 15 and also other Nikons with an adapter.

Final thought regarding wide converters and the Wide ports like the SWP44 mentioned in some other posts. Keep in mind that the reason they are using wide converters and ports like the SWP44 - which is essentially just a wide converter combined with an underwater optic - on the prosumer housings for the FX1/Z1 and others is that those cameras don't have interchangeable lenses, so your only option is a wide converter. Generally speaking, if there is any way to get your main lens as wide as you want it it is a better way to go. So I think we want to concentrate on getting the Canon or Nikon SLR lenses to work, or just bite the bullet and get one of those Zeiss, Cooke, Kinoptic, etc. real lenses in the 9 to 12mm range.

Hey Guys,
Looks like "Evin the Great" has come up with the long awaited report for the Nikkor 17/35mm. Looks like we have the work horse lens sussed. Now for SWA and a super macro option.

Cheers,
Mark.