Here’s something you may not know about the old manual Canon auto bellows and macro lens: the threaded adapter that connects a 20mm f3.5 (or 35mm f2.8) macro lens to the bellows employs the same threading standard as the typical microscope objective, known as the Royal Microscopical Society standard, 20.32 mm diameter with a pitch of 0.706 mm per turn, dates back to 1896 when it replaced an earlier standard.
The impact of this design choice for macrophotographers is that one can use any standard microscope objective, adding a great deal of options for imaging with the auto bellows and potentially pushing the capabilities of bellows macro into photomicrography. This can result in some very short working distances, and the sterics of the objective and subject mean there won’t generally be a lot of room for illumination sources. I designed this simple 3D printed microphotography objective hood for use with bright transverse illumination such as from a fiber optic illuminator. You may be familiar with the type of lens flare that can arise from this illumination setup-typically a haze effect that decreases the overall contrast of the image while increasing the brightness, particular toward the middle of the image.
I took the images below through a 10X NA = 0.25 objective (on the right, with lens hood).
My camera battery is charging, no spare, and I don’t have a worthwhile illumination source handy to shoot proper test shots (these were illuminated with a handheld torch). Nonetheless, I couldn’t resist taking these half-portraits, and I’ll post them here as a teaser. I will use these gorgeous metallic bees for Lieberkühn tests as well. For now, enjoy these Osmia aglaia photos while my camera charges.