Common orange lichen, 2.5:1, Heesch

This photo isn't particularly spectacular, yet it marks the start of a new personal journey, my first steps beyond 1:1 macro photography.

A journey I didn't plan. I'm happy with 1:1 macro photography and had no unmet need. In fact, on live subjects I often cannot use the closest focusing distance of my 1:1 macro lens, which technically means it's not even macro. I'm fine with that, it's just a word, I care about the subject and its meaning much more.

Yet somehow I found myself suddenly owning the Laowa Venus 25mm f/2.8 2.5-5x Ultra-Macro lens. I made the impulse buy after a cool video about it by Thomas Shahan, whom enjoyed it very much. As it is relatively inexpensive, I pulled the trigger. As just a lens to play with, probably mostly indoors.

This one spontaneous action led to a gear catastrophe. Whilst in extremely favorable conditions one can still use 2.5x macro without much else, at 5x macro, everything changes. You need a macro rail, strong lights, specimen holders, special software, the list goes on.

As macro beyond 1:1 is not very common, I plan to add more "making of" info below such photos. Just so you can get an idea of what it's like.

To start with this first photo, it's a 2.5:1 macro, the smallest magnification this lens offers. You'll only get anything in focus at a 45mm focusing distance. You can't take more distance and have a smaller view (which is possible with my 1:1 macro lens). 45mm is of course extremely close to the subject, at danger of the lens blocking light. It's also difficult to add light, as the distance between the lens and subject is so short.

This lens has manual aperture control, yet aperture works completely different than usual at higher magnifications. The *effective* aperture is a result of this formula:

(magnification + 1) * aperture

For this photo, taken at f/2.8, this would be (2.5 + 1) * 2.8 = f/9.8.

At 2.5:1 and f/2.8, the depth of field (DOF) is as thin as almost not existing. So let's stop down (raise f number) to f/8 to get some more depth of field:

(2.5 + 1) * 8 = f/28

f/28 is really problematic. It creates light diffraction, strongly affecting image quality. What's worse, f/28 means almost no light. It's looking into a pitch black viewfinder in broad daylight. And this is just the beginning, let's use this lens' maximum magnification of 5:1:

(5 + 1) * 8 = f/48

f/48 is absurd. It requires insane amounts of light just to see anything in the view finder.

If the above is too confusing, the real-world consequence of this lens and its qualities are that even in the best of conditions (f/2.8, 2.5:1), this lens is extremely difficult to use handheld or in the field. You'd need a really tiny subject (< 1mm), great flash, lots of practise, and a subject that tolerates this tiny working distance.

In any other circumstance (bigger subject, bigger magnification) this lens can basically only be used by stacking many shots, and combining them. Much more on that later.

This first photo is a lateral view taken from a tripod at 2.5:1, depth of field is around 0.1mm. It's basically one of my early tests.