6 replies to this topic

[scotdiver]

Ok - managed to get the camera and housing into the water yesterday for the first time. Taken at Hondoq, Gozo.

Aquatica housing with 8 inch dome and available light at ISO 400.

Shooting raw with the zoom set to 12mm (not fitted the gear yet). Image taken at 1/750 @ f8 in about 7m. Quite a surge so lots of eel grass bits floating about.

Followed Craig's raw file processing - big improvement on original.

I notice the foreground is soft and distorted - is this because there is no extension on the dome port or just the angle of the shot?

Cheers
Robert

[kdietz]

Nice color.........did you use a filter?

I'm also curious about the high shutter speed. Why so fast, instead of going for more DOF?

Karl

[scorpio_fish]

I notice the foreground is soft and distorted - is this because there is no extension on the dome port or just the angle of the shot?

You should use port extension 18456 for better results.

I'm also curious about the high shutter speed. Why so fast, instead of going for more DOF?

At 12mm the additional DOF is minimal in this scene. The lens is sharpest at f/8-11 and will fall off dramatically at smaller or larger apertures. Roughly the same exposure could have been done at ISO200, 1/180, f/11. A shutter speed of 1/180 should be fast enough to hold the camera steady and freeze everything in this frame. It's always easier to figure it out sitting at my desk.

[scotdiver]

As a starting point I used ISO 400 which would have been needed with film in the F3 and 20mm lens.

I nearly bought the extension when I got the housing, but the shop looked at the set-up and reckoned I could get away without it. Will give them a ring and get one shipped.

I had an FL-D filter from SRB in the UK but did not balance it in the water - doh!

[kdietz]

That's nice to know about the lens. I'm still waiting on a housing to be able to start using mine!

[giftie]

I notice the foreground is soft and distorted - is this because there is no extension on the dome port or just the angle of the shot?

You should use port extension 18456 for better results.

Extension 18456 provides better results, but not good results, I still get edge distortion at 12mm f/8. At larger apertures f5.6 and f4 it becomes worse, much worse. Prefer to use the fisheye 10.5 rather than the 12-24 at 12mm...

[scotdiver]

I just started testing with the 10.5 fisheye on Tuesday - must say I like it a lot, but getting some internal reflections on some shots.