Lens to port/glass distance

Hi All

Sorry for this question if it is stupid. I was trying to find an answer for that on forum but without a lack.

I have a Meikon housing for my Sony Nex-5N camera and it has a fixed housing port so cannot be shorten. If I would change my lens to shorter one and there will be a distance about 2cm between lens and port glass what it will affect? Will it affect focusing speed or will it make a pictures blurry? Will be a different impact on flat port vs dome here?

Thanks

dgal

Hi dgal, Cześć!

Focusing speed - I don't think there will be any noticeable difference (if any) with either flat or dome port.

Sharpness - With flat port no issues. With dome port sharpness of frame corners will be affected (center of the frame will stay sharp).

Other thing to consider is vignetting. If your lens is too far from port, and especially if it's wideangle, you will see your port in the frame.

Regards,

Piotr

Piotr dziękuję!

Vignetting is not an issue, at least with dry test, so I will give a try in a month underwater.

Thanks

dgal