The really SMALL stuff

What dslr set up do you use for the really small stuff ?

You know, the stuff that is about the size of a 10 cent piece, little shrimp, baby flounder, frogfish the size of your finger nail etc.

I use a canon 20D body with ikelite housing so am curious what lens + adapters people use to get the magnification needed.

Most people with a cropped sensor will start out with a 100/105 then add some form of diopter. A Macromate is reported to work well with that focal length range. People will then add a 1.4x teleconverter and even combine that with a diopter. Some will even use a 2x converter but that becomes difficult for most to handle with the crop.

A larger lens, either a 150 or 180, can be used instead of teleconverters but they give up flexibility and close focus in exchange for some theoretical improvement in image quality. With longer lenses you will be more dependent on diopters to get the focus close enough. I think you are better off with a 100 and a 1.4x than a 150 unless you know that you will never shoot the 100 without the converter.

for the tiny stuff, shooting at 1:1 (stuff the size of your camera's sensor) or greater, you will want the canon 100mm macro lens (which does 1:1 max i think) and add a diopter or even a teleconverter to shoot small stuff.

Shooting at these magnifications is increadibly difficult. Focusing, steadying the camera, lighting and limited depth of field are all major challenges with super macro. A focusing light is almost a necessity, as is a bare sandy patch to rest yourself on in order to keep the camera steady.

There is a pinned topic "going beyond 1:1", or something like that, in the Digital SLRs/Housings forum. check it out. Cheers,

Chris