DIY small dome port for CFWA

I recently received one of Barry's domes to use with my new Nauticam housing. I am using a Nauticam / Nexus port adapter. I was concerned about the performance of the Sigma 17-70 lens in this dome. Attached are some photos using both the Tokina 10-17 and the Sigma 17-70. They look good to me. Next month, I will putting the dome to the test on some cenote dives.

TomC

Sigma 17-70 @ 17mm

Tokina 10-17 @ 10mm

Sigma 17-70 @ 17mm

Edit: I neglected to say how impressed I am with the build quality of this piece. It has a very robust shade that is fastened to the dome in an ingenious manner. That was one of the complaints I had with my old 6" dome - the shade was always getting knocked off when the deck hands placed my housing on the camera table - not anymore!

I recently received one of Barry's domes to use with my new Nauticam housing. I am using a Nauticam / Nexus port adapter. I was concerned about the performance of the Sigma 17-70 lens in this dome. Attached are some photos using both the Tokina 10-17 and the Sigma 17-70. They look good to me. Next month, I will putting the dome to the test on some cenote dives.

 

TomC

 

 

Edit: I neglected to say how impressed I am with the build quality of this piece. It has a very robust shade that is fastened to the dome in an ingenious manner. That was one of the complaints I had with my old 6" dome - the shade was always getting knocked off when the deck hands placed my housing on the camera table - not anymore!

Outstanding Tom! I used the Bare dome on my Nexus D80 rig with the Tonk 10-17 for the Manta dive on the Big Island last July. Except for the plankton backscatter, the pics are good. No plankton ==> no matas.

And your right, good construction and minimal size. I haven't tried the Sigma 17-70 with the Bare dome. What extension did you use?

If I can use this one port for the 10-17, 10-17 + 1.4 TE, and the 17-70, that just leaves the set up for the 105 macro and I am good to go.

TIA,

Bob

I haven't tried the Sigma 17-70 with the Bare dome. What extension did you use?

I do not know what extension you would use on the Nexus housing but I used a 40 mm extension plus the Nexus / Nauticam adapter ring on my Nauticam housing. I suspect that the adapter rings adds some extension itself.

I do not know what extension you would use on the Nexus housing but I used a 40 mm extension plus the Nexus / Nauticam adapter ring on my Nauticam housing. I suspect that the adapter rings adds some extension itself.

Thanks Tom,

That's a good place to start; likely 40 to 50 mm in total, I'll try 60 mm and work backwards.

Regards,

Bob

Are there any nauticam users out there using Barry's dome?

I am aware that this would need a nexus port adapter already but,

I am interested to find out about any extension rings required for

a tokina 10-17 with or without a TC. Thanks in advance for any replies!

Cheers,

Phil

Are there any nauticam users out there using Barry's dome?

I am aware that this would need a nexus port adapter already but,

I am interested to find out about any extension rings required for

a tokina 10-17 with or without a TC. Thanks in advance for any replies!

Cheers,

Phil

Tom (tomc) is [see above]

The extension is built into the Bare dome, so on the Nexus rig I can use the 10-17 with or w/o the 1.4 TC and no extension is required when adding the TC. I use the Nexus zoom gear for this lens and adapt the Nexus zoom gear for the Nikkor 12-24 with the TC. I suggest you will not need a port extension.

Bob

Are there any nauticam users out there using Barry's dome?

I am aware that this would need a nexus port adapter already but,

I am interested to find out about any extension rings required for

a tokina 10-17 with or without a TC. Thanks in advance for any replies!

Cheers,

Phil

Hi Phil,

Yes, there are several users of my port on the Nauticam housing. Like Deep6 wrote, a Nexus port adapter is needed, but no extensions are needed for use with the Tokina 10-17 lens.

Barry

After reading about Barry's excellent DIY mini dome, I decided to have a go at building one for my Ikelite setup by combining an old dome port with an old flat port. The rear end of the flat port would be used to mate with the housing, while the central portion of the 6 inch dome port would provide the curved front surface of the mini dome.

After some calculations/measurements I used a fine hacksaw to cut through the barrel of the flat port and smoothed the cut surface using some fine wet and dry paper on a flat surface. I then marked out a circle on centre of the dome, with diameter slightly larger than the external diameter of the barrel of the flat port (which is 4 inches). I cut out this 'circle' using about a dozen hacksaw cuts, and smoothed the cut edges of the dome, again by rubbing it on wet and dry paper on a flat surface. When the external diameter of my new dome was equal to the external diameter of the barrel (ie 4 inches), the two cut surfaces were glued together using acrylic cement.

Once the cement had dried I painted the barrel inside and out with flat black paint to cut down on reflection. I made a port shade out of a short piece of PVC drain pipe, re-sized for a snug fit then painted flat black.

Now, while the outer barrel diameter of this port might be 4 inches, the dome radius is 6 inches and I note Barry's dome has a 4 inch radius. This doesn't seem to have created a significant problem for me apart from the fact that it was designed for a Tokina 10-17 with 1.4 teleconverter, and it won't work with the Tokina on its own (at its widest the lens takes in the edges of the port). But a big plus is that it cost virtually nothing to make, and another advantage I found is that the existing Ikelite zoom gear works fine with the Tokina fisheye plus TC.

Sorry I didn't take a few photos of the construction phase. I've since ordered a 4 inch acrylic dome that I hope to use to make another mini dome port for the Tokina on its own, so if anyone's interested I'll post a few pics of the steps in that.

After reading about Barry's excellent DIY mini dome, I decided to have a go at building one for my Ikelite setup by combining an old dome port with an old flat port.

 

Now, while the outer barrel diameter of this port might be 4 inches, the dome radius is 6 inches and I note Barry's dome has a 4 inch radius.

Great job Casbba and what a pretty nudibranch! Looks like from the image you sent, the dome is working great. Isn't it a neat feeling to build something that works?

Wetpixel member, Bill Libecap, also was inspired by the article and has a dome for the Ikelite housing which he has found successful.

Just a note, my dome actually comes to 4 3/4 inch dome area on my final design. I know that is not much difference, but going larger produces a much better quality image.

Please keep us informed how your dome is working with different types of images as well as any other DIY projects you have created.

Barry

www.creativeillusionsphoto.com

www.marinekeywords.com

Thanks Barry, and yes it is a nice feeling when you can build something yourself. I used to construct my own housings for film, movie and video cameras out of acrylic sheet. All pretty basic DIY stuff and I finally gave up when digital SLRs came on the scene and needed so many controls.

Having just re-read my previous post I see I got mixed up talking about radius and diameter, but I think you grasped what I was getting at. Just to clarify, my mini dome has a 6 inch diameter (not radius) and I'm using a 4 inch section of it. Hope this makes sense.

I'm not sure where I got the idea that your mini dome had a 4 inch diameter, but I'm interested that you say a larger diameter dome gives a better quality image. Is this because curvature of the virtual image matches curvature of the dome and so impacts on focus? If so I'm wondering if I should stick with a 6 inch diameter dome and a slightly shorter barrel for my next attempt. The problem I have with the existing one is that the port is a little long for the Tokina without a TC, and at its wider settings the Tokina catches the edge of the dome in the frame.

Thanks for your advice.

John

I received one of Barry's domes last week and have had a chance to do a quick pool test.

I must say I am really impressed with it and the only limitation so far is the user.

Hope to get some more time underwater with it soon.

Cheers,

Phil

Thanks Barry,

I'm not sure where I got the idea that your mini dome had a 4 inch diameter, but I'm interested that you say a larger diameter dome gives a better quality image. Is this because curvature of the virtual image matches curvature of the dome and so impacts on focus? If so I'm wondering if I should stick with a 6 inch diameter dome and a slightly shorter barrel for my next attempt. The problem I have with the existing one is that the port is a little long for the Tokina without a TC, and at its wider settings the Tokina catches the edge of the dome in the frame.

 

Thanks for your advice.

 

John

Hi John,

The diameter of the dome was selected to keep the virtual image the same distance from the lens' nodal point. The virtual image is not flat, but is formed off the water/air interface curvature of the arcylic port. By keeping the virtual image the same distance all around means that the lens will focus on the same point all the way around, giving the lens only one spot to focus on. Having only one spot to focus on means all the image from edge to edge is sharp. I hope the last couple of sentences make sense. I am not an optical engineer, so my explanation may be suffering. The main point is that the image is sharp from corner to corner and edge to edge.

The real test of your port will be the edge to edge sharpness. Once you can figure out how to keep your distances constant, you will have your winner.

Barry

nice !!

Wetpixel member Barry Guimbellot (Dupsbear) has a great article on the front page about making your own small dome port for CFWA photography. The end result looks amazing.

Hey DIY'ers,

I found a cleaner looking way to seal a dome to a metal port housing. The idea is to have a small gap between the housing and the dome, but the gap is smaller at the top than the bottom. Once an o-ring is compressed into the opening, the o-ring and port are very difficult to remove.

The blue in my image is a compressed o-ring that is larger at the bottom than the top.

The real trick is to find the right dimensions to compress the o-ring, but have enough clearance to get the o-ring in place.

The more pressure on the o-ring, the better the seal. This method does not seal better than the industrial superglue and silicone I used to use, but the new process looks better.

This is the same process that was used to seal the front glass on Nikonos 35mm and 28mm lenses, so the technique has a proven track record.

Happy creating,

Barry

www.creativeillusionsphoto.com

www.marinekeywords.com

Hello, as someone know... I own a rare camera with a magnificent housing. When I say "rare" I mean a non common camera for underwater use.

I am looking for a CFWA dome for my Olympus E-3 from one year ago and... I decided to buy the Barry's dome port.

I know that I have some risk to don't get the expected results but... I want to try it.

In a couple of week I will go to Red Sea and I will can try with "real fire".

Stay tunned.

In a couple of week I will go to Red Sea and I will can try with "real fire".

 

Stay tunned.

Hi Rajesh,

I hope you got some good pictures in the Red Sea.

I just came back from Anilao, Philippines and used the Bare Dome Port with my Tokina 10-17 lens. The combination works great, so I have included a few images.

The anthias next to the barrel sponge were taken at 17mm and both the other images were taken at 10mm.

Images were all sharp edge to edge.

The port is small and lightweight which handling underwater easy, not to mention packing the port for airline travel is easier than packing large ports.

Workmanship is first class on the port, so I would suggest it to anyone.

Thanks,

Judy

My selfmade DIY minidome for Hugyfot.

Thanks to Alex Tattersall and Geert Nies for parts and use off equipment.

My selfmade DIY minidome for Hugyfot.

Thanks to Alex Tattersall and Geert Nies for parts and use off equipment.

Nice looking dome! Have you had a chance to test the dome yet for sealing and/or image quality?

We look forward to hearing your of your results.

Barry

www.bareports.com

www.keywordworkflow.com

Looks good Hedwig

My selfmade DIY minidome for Hugyfot.

Thanks to Alex Tattersall and Geert Nies for parts and use off equipment.

 

 

Hedwig is a specialist :-)