Using closeup filter together with a macro lens

Question

I am thinking about buying a 3 or 5 diopter closeup filter so as to add on the top of a macro lens.

Would you do this or would you advise against it ? Do you think it's good to try, or it is not something to dig into ?

The context: I'm learning photography, it's obvious I'm totally into proxy and macro photography. I have two macro lens which I am learning with: Sigma 014 18-300mm F3.5-6.3 DC MACRO, and Canon EF 24-105mm f/3.5-5.6 IS STM (which I'm not completely sure it is really a macro dedicated lens indeed).

I got pleasing results but I wanted even much more details. Extension tubes did add more details and now I'm looking forward having even more details.

So I am considering adding a +3D or +5D closeup filter so as to be able to catch more details.

In a nutshell, so as to paraphrase my question: would you try a setup consisting of extension tube + low budget macro lens + closeup filter ? Or do you think there is something wrong in my approach ?

Answer 1

You can get pretty darn close to an object with 68mm of extension tube & a regular 50mm lens. Any shorter & the lens will actually appear to focus inside itself, so you end up pushing your tiny object away with the front of it then wondering why you can't get any closer ;-)

Any lens becomes a 'macro lens' if you put extension tubes on it, as it reduces both the maximum and minimum focus distance.

If you're using a zoom as a macro lens, there's an interplay between how close you need to be to fill the frame vs how much zoom is required to achieve the same thing. Someone smarter than me can probably work out the math, but I find for really tiny objects you can fill more frame with a sharp image at 50mm & the object up close than you can at 300mm with the object further away, & at the same time reduce your background to little more than a vignette, giving really good separation.

This is a 2mm flower bud, 4-layer focus stack made by simply pulling the focus manually [before I owned a rail], with a 50mm f1.4 lens on 68mm extension, f-16 1/4s. The background is 2 different coloured towels, 3m behind. The vignette is just 'distance blur' between the two.

^{Click for larger images}

This is the best I ever achieved with a close-up adaptor on a 300mm macro lens - water droplet is a similar size to the bud above - nowhere near as good [though my technique has improved since, this method produces far too much colour aberration for my liking.

Answer 2

Most closeup lenses (filters) add some aberration, both chromatic and spherical. That said, most macro subjects are rarely completely planar, so some parts would always be out of focus.

Extension tubes will generally make a sharper image, and if you're willing to forgo automation features, a lens reversal ring can be useful.

You might also try focus stacking (z-stacking), since depth-of-field at high magnification is negligible. CombineZP is a free z-stacking application, and suites such as Adobe Photoshop also provide the facility.

Answer 3

No real harm if you experiment and mount a supplemental close-up atop your macro. Most quality close-ups are two element achromatic lenses (free of color error). Close-up's get a bad reputation that they don’t usually deserve.

A +3d converts to 1/3 X 1000 = 333mm and a +5 = 1/5 X 1000 = 200mm. What this means: With a +3 mounted and the camera set to ∞ (infinity), an object at 333mm from the front of the camera lens will be in focus. Likewise, if a+5 is mounted, objects 200mm from the front lens element will be in focus. Such lash-ups allow you to focus a little bit closer but don’t expect a huge magnification gain.