Best M4/3 lens for magnification?

Thank you.  Does that mean that the minimum focusing distance is irrelevant then, you just need to take note of the magnification figure?

Jim Salvas wrote:

carlo14 wrote:

Thank you. Does that mean that the minimum focusing distance is irrelevant then, you just need to take note of the magnification figure?

The magnification factor is most important, but minimum focus distance gives you an idea of how much working room you have. That's important in macro, because it becomes difficult to light your subjects at very close distances. In general, longer focal length lenses give you more working distance.

Right. There can be too much of a good thing though. Working distance on the 100-300 is something like five feet, which is great if you're shooting an angry hornet. It also gives nice background separation. But the long focal length makes you work a lot harder with static subjects like flowers that don't need the distance.

by the way, I misspoke on the 12-50mm. It's maximum magnification figure is 0.36x, still better than other non-macros in m43.

... which is still pretty respectable, when you consider that it's .72 ff equivalent.

The 12-40 is also pretty respectable in terms of close focus. It's not a true macro, but it's good for wildflowers and things like that, with 0.3x magnification.

My favorite is a legacy Canon FD 50mm that I picked up in mint condition for $60. There are quite a few similar lenses floating around. They're a cheap option if you don't mind manual focus and aperture.

1:1 is true macro, and it is same as 1.0x

2:1 would be 2.0x

1:2 is only a 0.5x

So when you know optical magnification (0.5x, 0.28x, 0.16x etc) or reproduction ratio (1:1, 2:1, 1:2 etc) then you can work out the size you get with sensor size.

1:1 with 4/3 sensor gives 17.3x13mm capture area.

1:2 with 4/3 sensor gives 34.6x26mm capture area.

1:1 with 35mm sensor gives 36x24mm capture area (3:2 ratio instead 4:3)

Olympus 70-300mm (4/3 mount) was great as with manual focus you got 300mm to be a 1:2 / 0.5x and that meant the focus distance was a 96cm from sensor, and lens was about 35cm then so you got 60cm working distance.

Olympus takes some serious proudness to have excellent close-up focus distances with tele and wide angles. It is like their 45mm f/1.8 is the "worst" contender for that group.

You can view MFD, FL and Magnification as interdependent.

The magnification is a factor of the focal length and then how close you can get to the subject at MFD.

If you then change the MFD so you can get closer whilst keeping the FL the same, obviously the magnification goes up

Or.

If you make the focal length longer without affecting the MFD then also the magnification goes up.

Also, focus and magnification are synonymous at close distances, which is why macro lenses often have markings such as 1:1, 1:2, :1:4 on the barrel for focus ring.

Working distance is another important consideration,  and is solely a product of focal length. The 4/3 35 macro gives "true" 1:1 but the distance to subject is very short, making shadows a problem and tracking critters a challenge. Adapted 150mm macros are sought-after for these reasons.

Cheers,

Rick