I want to do some extreme macro work, so which lens is best for this? I think the Canon 100mm macro isn't good enough. So which lens gives great low light work plus will get me right into the eye of an insect, for example? Suggestions please.
No macro lens will do in low light. At macro distances depth of field is so scarce you'll probably be stopping down to f/11 or more. All macro lenses gather very little light at this setting so you'll most likely need an external lightsource.
To get up to photographing the eye of an insect you'll need to go way past 1:1 using something like the Canon MP-E 65mm. This lens is very difficult to shoot with due to the extreme magnification so don't expect results straight away, good macro photography takes years to perfect.
I shot with the MP-E 65mm lens (borrowed) and own both the 100mm macro lenses (L and "non-L"). Here are my insights:
- 100mm "non-L" lens: Great lens, autofocus can be a tad slow. Watch corners for chromatic aberration if you have very contrasty edges. Otherwise, well worth the money.
- 100mm L lens: Incredible lens. Autofocus is snappy and the lens is both clear and sharp from edge to edge of a full-frame sensor. If you have extra budget, this is money well spent.
- MP-E 65mm: Pretty weird lens, in my opinion. It has up to a 5:1 magnification factor. You can read a nice write up here. The biggest challenge with this lens was wedging sufficient light in because the lens was pretty much touching the subject. I've included a sample shot with this lens. You'll note how insanely shallow the DOF is even though the image was made at f/16.
So, if you want to do super macro, go for it, but this is not an easy lens to use.
I think you're looking for a lens which simply does not exist.
The Canon MP-E 65mm Macro Lens can take photos up to the eye of an insect, but it's not intended for low light work.
Conversely, the Canon 100mm L IS USM is a lot more practical for low light (because of the image stabilisation) but won't take the photos you want with regard to the magnification.