Hi folks, I hope all is well.
I want to get a macro lens and I currently use the S5 and G9/GX9 systems.
I just wondered if there were any disadvantages to using M43 over FF for macro photography.
Reason for asking is I may at some point move away from the S5 / L mount system (waiting to see what comes out in the not too distant future) but I will keep my G9/GX9 regardless. So don't want to commit to the Sigma 105 at £600-£700 for the S5 if I later move away from the L Mount. But if M43 is good for macro then I may just get a lens for my G9 and leave it at that.
I hope that makes sense.
Adam
Assuming you use the same focal length on both formats, you get two advantages due to the image size needed to fill the M43 sensor being roughly half the size needed to fill the full frame sensor: More depth of field and greater working distances. The importance of these (depending exactly on what type of close up photography you want to do), cannot be overestimated.
If, however, you use a 50 or 60mm macro lens on m43, and the 105mm on FF, while still gaining depth of field, you lose the working distance advantage.
Depending on how close you are working (ie the magnification needed) you cannot rely on, for example a 100mm lens doubling the working distance of a 50mm lens as it depends on how the different lenses achieve their close focussing capability.
With many lenses they do this , not by extending the lens (the old fashioned way), but by changing it's focal length as it focusses closer. So, for any given magnification, you end up with a much shorter working distance than a simple optical calculation would suggest. Knowing the marked focal length of a lens, when it comes to close up photography, is not a good indicator of working distances. You need to check the closest focusing distances and magnification values from the lens specs. I don't know what these are for the obvious 60mm M43 macro, compared to the Sigma you mention
There are two possible advantages of FF for close up photography,
The first is when you want to minimise depth of field. Most of the time this is the opposite of what you want, but I occasionally take close ups of flower photographs with a 300mm f4 on FF, because I want a super soft foreground and background with only slivers of of flower(s) in focus. But this is unusual, and even with the increased depth of field from M43, it's still generally pretty narrow.
The second possible advantage is the M43 vs FF image quality debate, and this depends a bit on what you intend photographing. With Closeups, the subject tends to be relatively large in the frame, so the impact of noise is probably less important than in some other types of photography. I suspect that generally there will be little obvious/important quality advantage from FF.
