Even though we like toys really a lot, this is post is not about “my lens is longer than your lens” (well … maybe a bit) but something i always wanted to try: A Mini Review about the practicability of a longer Macro like the SIGMA 150mm Macro or the Canon 180 Macro on APS-C for diving in the Lembeh Strait. As since some time there is a newer version of the 150mm on the market – that Simon happens to own since this year – the choice was made. So i took the SIGMA 150mm 1:2.8 APO MACRO DG HSM out for 3 dives to compare. It does not fit into my INON Ports with magnetic focus so i have to use normal Nauticam Ports. Luckily Simon got the lens with a custom made Focus Gear from Ryan at REEF Photo that let’s me use manual Focus.
On a Canon Cropped Sensor this lens is equivalent to 240mm focal length on full frame. While i have been shooting the 100mm a lot with 1,5 and 1,4 Teles i always wondered if i would prefer a 150mm prime over the combination of the 100mm with a Tele. While the 100mm / Teleconverter combination gives you extra magnification and maintains the minimum focus distance of the 100mm, the 150mm prime only get’s you to 1:1 and you have a longer minimum focus distance – but you gain light, focus speed and picture quality. To make up for the loss in magnification i am adding a Diopter Flip Holder for extra magnification. For the test i used a Nauticam SMC.
First impressions under water: Even though it is by far not as fast as a 100mm on its own it focusses much quicker than a 100mm/Tele combo and i did not use a focus light for any of the shots (except the ones taken with the SMC). I also rarely used the manual Focus (also only on the SMC shots). The main reason to shoot a long lens like this is obviously working distance so you aim to shoot shy subjects like Shrimp Gobies or Garden Eel. Which i also did. But like it is when you go out to shoot something you always find other cool stuff on the way. Specially in Lembeh. So while i was heading to shoot Gobies i ended up shooting Frogfishes and Octopus for most of the time. Which was in the end not a bad thing. Because i realised that the lens is not all that unsuited for these subjects. Even though you have to back off on bigger subjects it is still a very nice lens for smaller Frogfish and Octopus. Specially because the 9 Aperture Blades of this lens produce very beautiful out of focus area on the photos. Other than that the lens is absolutely spectacular to shoot Gobies with – i really really enjoyed it.
Once having found out how universal the lens is i couldn’t wait to test its Super Macro Capabilities: So i found a small Nudibranch, gave it a shot and liked it from the first moment. The longer minimum focus distance of the 150 suddenly turns into a big advantage with the SMC – because you gain some extra distance to the subject when working with this strong diopter. Which makes it way easier to light the subject and also to choose how you want to light it.
Buoyancy: As the 150mm is a relatively heavy lens and the SMC on the flip holder is also not exactly lightweight the whole rig tends to tilt slightly forward but was not overly heavy in total. I balanced this off by moving my INON Mega-Floats that i always use slightly forward instead of slightly backwards as i usually use them.
Conclusion: Even though one might think, that a 150mm is a special interest lens to use on an APS-C … i have to say that it actually a very good semi-allround macro lens. It is the first choice for shy subjects like Gobies or Garden Eels but also the much better to use with an SMC compared to the 100mm (due to the marginal gain in working distance). And in between it offers a good lens to shoot normal Macro as well – as long as you don’t choose too big subjects and properly position your strobes.