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?

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.