Perhaps Andi Voeltz will this as I understand he has been shooting this lens with Hugyfot ports.

Though many folks like the Tokina 10-17 FE for underwater I have been looking at the Canon 10-22 as I will use it a fair bit topside and prefer the straight lines. Hugyfot notes that it can be used with either a wide angle dome or a fish eye dome. Now I know that the preferred is to the fish eye dome but in doing some searching I could not find much on what the losses will be if using the wide angle dome.  The 10-22 is known to be a bit soft in the corners and I would expect some darkening as well. What other losses could I expect?

Also using the Fish-eye dome it is recommended that the 30mm extension be used. Though I have heard from one person who is using the Sigma 10-20 that they skipped the extension. Obviously a different lens but I am wondering the consequences of doing this.

Hi Allen,

what you are reffering to is dome port theory at it’s best....
If you have two 10-20mm lenses which you want to use in a
dome it is not a must that both of them need the same dome
and extension ring.

It is all about positioning it correct for the entrance pupil of
the lens an the diameter of the dome sphere. A bigger dome
will usually give you a sharper image but the trade-off is that
you do not travel as light-weight as with the smallest possible
dome for your lens.

The Canon 10-22 works fine in both Hugyfot Domes, but it is
easier to do split shots with the bigger (Fisheye) Dome. On the
other hand the small wide angle dome allows is more compact.

Hello Andi,

Thanks for the information. What you wrote is what I thought about the two ports. The fisheye gives a bit better image but the wide angle is more compact for traveling. Fortunately, the price difference is not significant. It makes for a hard decision.

One question that might help. At what point do feel the corners/edges start to get soft using the wide angle dome? Is it throughout the range or just at the very widest 10-12mm??

Cheers,

Allen