lens setting

i have just ordered a tokina 10-17mm which will be behind a sea and sea fish eye dome port. would like to know what would be the best setting to have the lens set at. i have shot WA with the 10-22 before and have always had the lens set to infinity. i would like to know if this is right. i am looking for close up WA shots and also reef scene shots.

many thanks, stew

Hi Stew,

You're going to love the new lens. I've used mine with both the 40D and the 400D with the S&S dome port. I found I just put it on Auto Focus and it worked great. We shot 1000 frames in Bonaire with it and all were in focus, most of the shots were focusing at the low end of the scale though, not infinity and I tried to stay at f8 or above. I'm sorry I don't have any experience with your 350D but I'll bet it's very similar. Not sure where your headed but in clear water I don't think you'll have an issue.

I know we say it over and over but with the 10-17mm your going to need to get closer than you think even compared to the 10-22. With the 10-17 the last 6 inches is critical. Oh yeah, don't forget to pull those strobes aft. Have fun! FWIW,

Steve

Hi Stew,

The Tokina has the ability to focus quite close so you don't need a diopter which is handy as there are no threads to accept one!

In the water you will find that there is virtually no focus movement on the lens at all - about the only time I have locked mine was shooting fast moving dolphins at night where the autofocus was just likely to get confused.

Pretty much at all other times I just let the AF do as it wants and seldom see a shot that is 'off', including CFWA - this lens has enormous depth of field by design, when you shoot CFWA go for as high an F stop as you can and single point focus on the close item, let the DOF do the rest.

It is a great lens though I am not as enthusiastic as some - the CA annoys me somewhat.

You will have fun with it.

Paul C

cheers for the replies guys, i will be using it in the red sea in october so the viz should be really good with nice blue waters.

then its back off to the maldives for a 2 week liveaboard in january so hopefully whalesharks and mantas. of course i will post my best efforts on my return.

once again cheers

be advised that just using it at infinity setting may not work to your liking.

the dome port makes a virtual image, and the lens focusses on that. The virtual image is mostly at a much closer distance than infinity. Depending on your aperture, the image may or may be not in focus.

be advised that just using it at infinity setting may not work to your liking.

 

the dome port makes a virtual image, and the lens focusses on that. The virtual image is mostly at a much closer distance than infinity. Depending on your aperture, the image may or may be not in focus.

i have been reading another thread regarding this subject and to be honest it has completely lost me !!!!

so would i be right in thinking that the image that the sensor records is actually an image that is on the inner surface of the dome port. so a shorter than infinity setting would be appropriate.