Subal Macro port help

I recently bought a subal housing for my 5d ii and am looking for a macro port. I want to buy used because I can not afford to pay for a new one. I see plenty of 3rd gen 105vr macro ports for the nikkon 105vr lens but no ports for the 100mm canon macro. The ports look identical. Does anybody know if I can use the 105 port?

You may want to specify which of the three EF 100mm macros you have. In terms of Seacam I am using the same port for the 100L as for the 105VR (I have both). The manual focusing ring connects with the housing and not the port - see attached pic of 100L in Seacam - it is port length that is important in this case.

Good luck!

Tom

One idea would be to skip manual focus and go with the much less expensive FP-120 port... Autofocus combined back focus driven "lock & rock" techniques is preferred by many users of these systems.

You could add a focus gear from XIT404 at some point in the future should you determine that actual gear driven focus is needed Some prefer the ergonomics of this solution too, driven from the knob on the housing instead of the port.

Ryan:

Could you elaborate on "back focus lock & rock technique"? Shooting with a 105 mm has frustrated me to the point where I'm thinking of switching to a 60 mm with a diopter. If I do I'd probably go with the port that doesn't have manual focus. Thanks.

i try to explain this from my perspective:

First, activate AF on the AF-ON button for AF only and use AFC (continuous AF camera setting). Then focus on your subject or to the closest focus distance for your lens (depending which magnification you desire), then release the AF-ON button to lock focus. Now holding the housing with your right hand only (housing must be relative neutral for that off course) while holding your body position with support from your left hand (holding on a stone but not a coral etc; I also like to use one of these Lembeh sticks). Now you move slightly the rig back and / or forward until the object is fully in focus i.e. appears sharp in your viewer (a magnifying viewer especially one of those 45 degrees viewer will help in this respect); immediately press the shutter trigger and take the image.

With manual focusing you will need both hands on the camera and will miss in critical situation or make it impossible to take a sharp image in currents.

Thanks. I'll definitely try that.

Cheers, Tom