I wonder about the DOF of the CMC2 compared to the CMC-1 lens

I have a MFT camera (Olympus) in a Nauticam housing. When I dive with macrolens (mostly a 45mm) I add a CMC-1 on a flip adapter. However, I don't like the combination, for me the DOF is to narrow. As I am also not very interested in supermacro, I am thinking about buying a CMC-2. Jet I doubt if I will be disappointed with the DOF of that wetlens as well.

Can someone tell more about the DOF improvement after moving to a CMC-2?

Edited December 12, 2025Dec 12 by Davide DB
title typo

Depth of field is a function of magnification, if you reduce the magnification on the sensor you get more depth of field at constant f-stop. There are special cases with wet lenses but shouldn't apply to a simple diopter. Bearing in mind of course that the depth of field is already razor thin at less than 1mm with the bare lens at 1:1 magnification.

On 12/9/2025 at 11:03 PM, Floris Bennema said:

I wonder about the DOF of the CMC2 compared to the CMC-1 lens

I have a MFT camera (Olympus) in a Nauticam housing. When I dive with macrolens (mostly a 45mm) I add a CMC-1 on a flip adapter. However, I don't like the combination, for me the DOF is to narrow. As I am also not very interested in supermacro, I am thinking about buying a CMC-2. Jet I doubt if I will be disappointed with the DOF of that wetlens as well.

Can someone tell more about the DOF improvement after moving to a CMC-2?

I should start by saying I only shoot video with a GH5.

I have the CMC-2 and I use it with a Leica 45mm or the Pana 14-42mm (a combination I hate). With the zoom, the situation is more complex because, as Chris said, the depth of field is a function of magnification, and many times I work at minimum zoom, almost to the edge of vignetting.

With only the 45mm, the DOF is acceptable. This creature is about 9/10 mm long, and if you look at the grains of sand, you realize the DOF (1/100, f/10). I definitely could have gotten closer, but it was running like there was no tomorrow.

However, with the 45 mm + CMC-2 even a Caprella sp. goes out of focus if it moves.

Years ago, I had the opportunity to test the CMC-1, CMC-2, and Subsee +5 on several dives. The Subsee was the least powerful but easiest to use. The CMC-1 was the opposite. The deciding factor for me was the focus range (5 vs 10 cm). For video and the types of subjects I usually encountered, the CMC-1 was truly difficult to use, so I chose the 2, which was a bit of an all rounder. Now that I've gotten the hang of it, I wish I had the CMC-1, maybe something even more extreme. Naturally, only for static subjects.

Agree with Davide: the CMC-2 is much easier to use. I tend to dive with that versus the CMC-1, which is taking up space in a drawer gathering dust. I also liked using the Inon 165, which are easily stacked if you want more magnification.

DOF (in general) goes down as the square of the magnification (with several aproximations) so the CMC 2 will be a bunch better. But whether or not it is to your liking is a question.

Bill

Thank you for your reactions. I use the same 45mm Leica lens Davide uses, and from your reactions I think the CMC-2 will be better to my liking. Probably my CMC-1 will be gathering dust here as well.

Late to the discussion, but I find it interesting as I prepare for my first muck trip to Lembeh in July. I had good results in Roatan with static subjects using my M43 60mm macro plus an Inon 165 (+6 diopter), and even with a borrowed +15 diopter.

Based on getting decent Costasiella sp. pics in Roatan with +15 I think I want to add more magnification than the +6. My original thought was just to add a ~+10 so I would have +6, +10, and+16 by mixing/matching. I’ve gotten advice that I’d be better off with a Nauticam CMC-1 to use instead of the Inon +6 and not try to stack. Of course I’ve also gotten advice that I should get an MFO-3! (It’s only money!🤯)

In addition to the 60mm I am adding a 30mm OM and 45 mm P/L to my kit to experiment with. (The 30 is primarily for blackwater and the 45 is based on @bvanant ’s advice that it is a great all-rounder macro lens.

Any advice would be appreciated. Thanks!

Evan

Edited 21 hours ago21 hr by ACHiPo

20 hours ago, ACHiPo said:

Late to the discussion, but I find it interesting as I prepare for my first muck trip to Lembeh in July. I had good results in Roatan with static subjects using my M43 60mm macro plus an Inon 165 (+6 diopter), and even with a borrowed +15 diopter.

Based on getting decent Costasiella sp. pics in Roatan with +15 I think I want to add more magnification than the +6. My original thought was just to add a ~+10 so I would have +6, +10, and+16 by mixing/matching. I’ve gotten advice that I’d be better off with a Nauticam CMC-1 to use instead of the Inon +6 and not try to stack. Of course I’ve also gotten advice that I should get an MFO-3! (It’s only money!🤯)

In addition to the 60mm I am adding a 30mm OM and 45 mm P/L to my kit to experiment with. (The 30 is primarily for blackwater and the 45 is based on @bvanant ’s advice that it is a great all-rounder macro lens.

Any advice would be appreciated. Thanks!

Evan

I was in Lembeh last year and I just used the 60mm and MFO3 and I think I had half a dozen subjects where I thought I might have needed more magnification. The 60mm on m43 at max magnification covers a frame that is 17mm across which is quite small, easily suitable for 10mm long subjects. If you want more magnification the CMC-2 covers a frame 10mm across at 33mm working distance. The CMC-1 gets to 8mm across at 22mm working distance. To me even the 33mm working distance is difficult to light well and I recall quite a few posts expressing that the CMC-2 was the more useful option because of this. The CMC-2 is about a +10 as I recall.

I did however find plenty of subjects where the MFO3 was useful, larger frogfish, scorpionfish, rhinopias, pipefish, octopus, mantis shrimp and also every site has lots of anemonefish of many different species - I can't swim past them. Even subjects that you could get away with the 60mm benefit as you get in so much closer when using the MFO3 making backscatter control easier. My Lembeh trip report is here: