A New Macro King? Alex Mustard on the Sony FE 100mm F2.8 Macro GM

In this article from The Underwater Photography Show, Matthew picks Alex’s brain on the new Sony G Master 100mm macro.

We know a lot of you have been clamoring for information on this new lens, and we finally have the details! Alex had the opportunity to put the new Sony GM 100mm macro through its paces in Lembeh, Indonesia, although it was a 'skin of the teeth' operation—the lens arrived with workshop guests coming from London, and Nauticam hurriedly sent the port to Singapore for a pickup as other guests passed through. Despite the rush, Alex was able to shoot well over 3,000 pictures with it, using it on about a third of his dives during the trip, gaining a rounded impression.

Overall Impressions: The Best Macro Lens

Alex Mustard: The headline for me is simple: I really, really like the lens. I think it's the best macro lens that I've shot on Sony and I would even go as far as saying I think it's the best macro lens I've shot, period. In terms of specifications, its closest competition is the Canon RF 100mm L, which is very similar. I'd like to shoot them back to back to truly decide, but without this opportunity I’d put the Sony 100 as top.

The main reason I'd vote for the Sony is its ability to take teleconverters, which is probably the most exciting thing about it. This instantly gives access to different focal lengths and more magnification options. That said, it’s important to note that it's the best by a small amount over other macro lenses. It's a small gain in lots of categories, not a revolutionary leap. It’s an evolution, not a revolution. [1:15]

Port Compatibility

Alex Mustard: I initially tried the existing Nauticam port for the 90mm macro lens, but it proved to be unsuitable for the new Sony GM 100mm lens. The primary issue is the specific molding inside the old port, which prevents the new lens from pushing up against the glass. The 100mm lens is only about 18 mm longer than the 90mm, but the smallest extension that worked with the old port was a 30mm. Therefore, my advice to fellow Nauticam users is clear: if you are purchasing this lens, you are better off spending the money on the dedicated port for it, as the flat port you likely already have isn't going to fit. [4:55]

Performance and Image Quality

Matthew Sullivan: When you were using it in Lembeh, a place where focus is critical, how did you find the new autofocus system performed?

Alex Mustard: It's absolutely phenomenal. I was particularly impressed with its ability to nail focus on Blackwater. The lens does an incredible job of finding and locking focus, which, combined with the camera body's focusing system, allows you to capture those tricky, tiny subjects. When you look at the final images, the image quality is "proper quality," with all the details super well-rendered. [9:45]

The fact that the lens is capable of exceeding 1:1 magnification and reaching 1:1.4 is really valuable. Perhaps even more noticeable is the background rendering. This lens produces gorgeous, gorgeous bokeh, which is a huge benefit for macro, helping your subject truly pop off the background. [16:23]

The Teleconverter and Working Distance Advantage

Alex Mustard: The teleconverter is the game-changer for me. I was so impressed with how the lens shot with the 1.4x teleconverter. Normally teleconverters make a noticeable drop in image quality and make autofocus a lot slower. Not so here. So you can simply use a teleconverter to give a more telephoto look, which naturally helps in separating the subject from the background. It also gives you that extra bit of comfortable working distance, which is essential for small, timid fish that might dart away if you get too close.

I was so impressed with how this lens worked with my Sony 1.4x teleconverter that I have ordered a 2x teleconverter to arrive with my own lens. As a traveling photographer, they are relatively small additions to baggage allowance and they give you real flexibility and options.

Another positive for the 100mm is that it worked perfectly with all existing macro accessories. My options in Lembeh were MFO-1, MFO-3, SMC-3 and EMWL-160 and all worked fantastically well. The MFO-3 is particularly valuable when using the teleconverter. Having a 100mm lens and a 1.4x teleconverter attached typically limits the kinds of subjects you can shoot to only smaller critters. However, because it works well with the MFO-3, which widens your field of view by quite a bit, it creates a versatile and powerful setup. [20:20]

The Final Verdict

Alex Mustard: This is a quality product and I believe it is the best macro lens out there. If you currently don't own any macro lenses, this is absolutely the one to go for. If you already have the older, very capable 90mm and are generally happy with its image quality, then the decision is harder. This is an expensive upgrade, but the gains are sublte and multifaceted, rather than one clear transformation. So for most Sony shooters, who will already have a 90mm, you will have to answer “should I get one?” yourself. But for those that do make the jump, I can assure you, you will be upgrading to the best. [33:51]

You can watch the full conversation between Alex and Matthew about the new lens in this video.