Dome ports for Sigma 15mm and Canon 16-35mm

I've been shooting NA-7Ds for a couple of years and already have Zen DP-100 and DP-200 dome ports. I'm pretty keen on adding a Mk3 and NA-5D3 in the near future and my immediate investment in glass for the FX format will be the Sigma 15mm and the Canon 16-35mm and maybe later, the Canon 8-15mm. Staying with the Zen stable, with which I have been very happy shooting the Tokina, 10-22mm and 17-70mm, which domes should I be considering for the FX glass? Would my existing DP-100 do the Sigma 15mm justice? If so, perhaps I'll need to shave the lens hood... But I wouldn't be too keen on having to stop the 15mm down excessively as I plan on using the Mk3 primarily for deep, low ambient light and high ISO work. I expect the Canon16-35mm may perform best with the DP-230 and I know there's a dedicated shadeless DP-100 planned for the 8-15mm.

Any practical advice gratefully received. Many thanks, Tim

The bigger the better for the 16-35. When I tested the 5D2, the 16-35 had workable corners at f9 with an 8" dome, but going to the Superdome (which is 240mm), it was better even down to f8. If you shoot below f8, put a +2 diopter on.

Thanks Drew. I figured that a diopter may be required with the 16-35.

I'm not that fussed about shooting with the Sigma 15mm behind a mini-dome. If I intend to shoot CFWA then I'll use the 7D, Tokina, Kenko and Zen 100 which does that job perfectly. Where I see the Sigma 15mm on FX is for wide-angle, high ISO shooting and I'm guessing that a mini-dome in that situation is going to mean that I'll have to stop the glass down more so than if I were using a larger dome, i.e a Zen 200 or Zen 230.

I'd skip the Sigma and go straight for the 8-15. You can then dump the 10-17 too since it works well for both APS and FF. With APS, the 8-15 is actually wider since the 10-17 isn't 180° with the canon 1.6x crop.

The only diopter available for the 82mm 16-35/2.8 L II that I know of is made by Schneider, and it (+2) actually makes corner sharpness worse in both DP-200 and DP-230. Surprisingly counter intuitive, and I didn't see that same degradation using single element diopters with the original.

Zen 230 and Seacam Superdome have the same radius of curvature and thickness, so image quality will be identical with the same placement.

DP-230 is certainly better in the corners than DP-200 with 16-35, but since you own the DP-200 you can test them for yourself to see if they are good enough.

8-15 is the first fisheye or fisheye zoom that I'm comfortable using with a teleconverter, and I love the range 8-15 + 1.4x TC covers on full frame.

I just realized I've been saying +2 when I've been using a +1 diopter. Opps! Too many systems mixing together! I got the Vivitar 86mm +1 diopter and use a step up ring. No vignetting.

Ryan, you are going to make me bring out the measuring tape aren't you?

8-15 is the first fisheye or fisheye zoom that I'm comfortable using with a teleconverter, and I love the range 8-15 + 1.4x TC covers on full frame.

That's an interesting thought Ryan, thanks. Which TC have you used with the 8-15? With the addition of the TC I assume that the change in the FOV will remove all or most of the circular FE image. Is that so? I guess you will have used this glass with the DP-100 (I have one of the early versions without any built-in extensions). Are the sun shades visible when shooting the 8-15 with a TC? Many thanks for your input, Tim

I use an older kenko pro 300 that never locks focus (which is fine because I back focus), but someone here says newer "blue dot" models work better.

http://wetpixel.com/forums/lofiversion/index.php/t46415.html

Using the dome you have with a 30mm extension should give you an 11-15 range with no vignette.

Just tried the Kenko DGX version today. It does lock focus, albeit slower. They did not have a Tamron SP Pro so I bought the DGX!

Hi guys,

Very interested in using a canon 8-15 both for circular fisheye and general shooting. I'd use my Zen 200 dome port with the shade removed on my Mk3 for the circular fisheye, and I'm considering getting a Zen 100 to use both with & without my Kenko 1.4x DGX for CFWA, as circular fisheye shooting isn't possible on the micro domes yet (might hold off until a removable shade option is available).

I'm wondering if anyone has any experience shooting with the 8-15 in a Zen 200 port, and if so what extension rings they used for best results both with the 8-15 alone and with a 1.4x teleconverter? Same goes for the Zen 100: If you're using the 8-15 behind the Zen 100 NC designed for that lens in particular, what extension ring are you using when you put the teleconverter on?

Thanks!