6'' vs 8'' dome

Good morning underwater photographer friends.

I recently got a new Canon RF 14-35mm and wanted to use at 14mm underwater.

I need to buy a dome, having the 6'' and 8'' options. The 6'' is cheaper and much easier to carry on a trip because it's small.

Will I notice a difference in the image quality, especially in the corners of the photo? What's your experience?

Thank you very much for your attention!

stillviking wrote:

Good morning underwater photographer friends.

I recently got a new Canon RF 14-35mm and wanted to use at 14mm underwater.

I need to buy a dome, having the 6'' and 8'' options. The 6'' is cheaper and much easier to carry on a trip because it's small.

Will I notice a difference in the image quality, especially in the corners of the photo? What's your experience?

Thank you very much for your attention!

given how new the lens is, you probably won't find a lot of experience to answer that question well.

I do have the lens, and I took it to Palau in October, but Nauticam was a month too late getting the zoom gear to me, so I had to preselect the FL for each dive.  Not surprisingly, I spent a lot more time using the 8-15.

I am using S&S AR210 lens as the most travel attractive option for both the 815 and the 1435.   It is considerably lighter/cheaper than the glass 230 options and it would be difficult to see a real different optically per Backscatter.   Getting the right (good enough) port extension is also key here - I was able to use the same 50 extension for both the fisheye on a 1.4x and the rectalinear.

Is this lens in addition to the 8-15?   If as wide as possible is key, then that lens is the better choice (can go to 140mm on dome), with the obvious caveats.  Part of my interest was the ability to do little critters at 35mm.

Traditionally rectalinear lenses want as big a dome as you're willing to haul.   Nauticam does list the 180mm glass port (7") as suitable, while Aquatica only goes as small as the 8.5" Acrylic.   It's possible that with a 6", you'll see the shade covers at 14.

What housing would this be for?   Did you get it from one of the major players like BS, Blue Water, Reefphoto?   All of them can advise with better knowledge on the combos.

I bought Nauticam's port cover/luggage for their 230 and this makes packing easier, but I'm forced to check it in, along with the macro port.  The camera/housing I carry as my personal carry on piece, and the lenses and strobes go into my thinktank roller carry-on.

Yes, it is pretty new that's why I was interested if anyone tested it underwater!

I don't own the 8-15 mm, that is my wider lens! So I was planning to use at 14 mm!

I have a "surfing housing" only to go until 10 meters, I can buy a dome but don't know if 6'' will make me soft corners!

and what are your intended subjects?   Will it be surfers and waves, primarily?

Most UW photographers use the fisheye more of the time, and the captured image is much wider than is possible with the 15-35 class of wide angles.  But I don't think that would be right for surf photography.

Are you going to be using strobes or natural light?

Do you have a zoom gear, or would you just be setting it to the wide setting?

Over/unders are also easier with an 8 or 9 than a 6, and very difficult with a 4.

Also as I mentioned, it's important to get the distance between the lens and the dome correct, so that the edges aren't badly impacted.   The housing maker is the starting authority here.

I already have a surf setup (flat ports and some primes), now I want to addto it the dome for underwater shoots (people, dolphins, turtles, etc.).

I will only use natural light. No zoom gear in my waterhouse. I really don't need over/unders, planning to shoot all underwater.

I read the important in distance between lens and dome is to the lens be very close to dome acrylic, almost touching, correct?

Wow, I was totally wrong. Thanks!

So should we move the lens away from the dome glass as far as possible? Is this valid for fisheyes and rectilinear wideangles?