Very good comparison video of macro lenses for M43. Makes me think a little bit more than usual….
I think that just about everybody doing underwater macro with a M43 (Panasonic G9, GH5, etc and the Olympus OMD-EM1/5/10) is using the Olympus 60mm Macro. I haven’t seen any debate about this at all.
The reason that we all use the 60mm is because more magnification is good and the image quality of this lens is good. And hey, that’s what everybody else uses, so why not? However, I wish there were other good M43 macro lenses: a 100mm or 120mm would make me very happy although it might not be useable underwater.
But, we also have wet diopters (wet lenses), and they change the lens game considerably. I myself have both a Nauticam Supermacro converter SMC-1, a Saga +5, and an Inon super-wide macro (bug-eye). I’m have the additional magnifier for the SMC-1 coming next week for even better supermacro, although for the past 18 months I’ve been a heretic and stacked the Saga +5 on top of the SMC instead because the price is right.
My thinking goes like this:
- It’s harder to focus underwater because of less light. This means less contrast for autofocus.
- It’s harder to focus underwater because current and surge: you and your subject are constantly moving in large and small amounts.
- It’s harder to focus underwater because well, you’re underwater and breathing through a hose.
- A 30mm or 45mm macro lens plus wet diopters is an interesting option, especially if they have a faster autofocus. If you can shoot closer and/or use wet diopters, then you can even get to supermacro.
- A macro lens at a wide F-stop (F2.8 for most macro lenses) means a thinner plane of focus.
- Adding a wet diopter makes a thin plane of focus.
- Stacking wet diopters makes a very very thin plane of focus.
- I usually end up shooting at F22 with stacked diopters to increase my plane of focus as much as I can. Obviously, this changes my exposure so I have to compensate in shutter speed, strobe power, or ISO.
- It is very common for the lens to be able to focus in front of and beyond what the wet diopter is capable of. IE, the focus range of the lens exceeds the focus range of the diopter. This adds to difficulties in autofocus because the lens hunts in places where it cannot focus. Using a limiter switch on the lens (the Olympus 60mm has one) helps because it eliminates the hunting in the longer ranges.
- Focus lock helps a ton with wet diopters because it almost eliminates out-of-range situations unless you’re setting a new focus.
- For larger subjects (shrimp gobies, garden eels, larger crabs, scorpionfish, etc), diopters can also be unscrewed or swung out of the way with a hinge. I use a hinge for the SMC-1. I screw the Saga +5 on and off because it doesn’t have a downsize threads to fit the front end of the SMC-1. Screwing on and off is not a quick process.
- If you remove the diopter, then the focus is further away, so using a limiter switch on the lens means that you maybe can’t focus at that longer length. So really, using the limiter switch is a tradeoff between autofocus speed and being able to take pictures of larger subjects.
- You absolutely need to try all of the options available to you before you do it underwater. Dry-land training is huge.
What’s the point of all this? Well, everything in photography is a tradeoff. The more you understand what decisions you’re making, the more you can adjust when things don’t work out the way you intended. And I’m a huge believer in being able to adjust to conditions and just keep shooting.
See You Underwater!!!
–Mike