Client asked for macro work ..

[Maxence33]

Hi Everyone this is my first post.
I have been a macrophotography enthusiast for years, but not doing much lately due to my architecture photography activity..

Though one client today asked me if I could do macrophotography shots for him.

It is to shoot a kind of light beam cone of about 0.5 mm. This is achievable through a protection window 15 mm far from the subject.

First I think I will need to have a high magnification ratio. I am thinking of 20x. I used to do mostly X1 and single digit macro ratio through an Angenieux G10 enlarging lens.
I also own a Zuiko Macro 38mm f3.5 which working distance is around 30 mm at x5 so should be perfect. Yet I am not sure x5 will be sufficient for client.

I was wondering if you could point a good RMS lens that would fit my needs. I think I need to shoot an area of 2mm (a bit more than the cone size).. I hesitate between 10x and 20x.
I cant afford the Mitutoyo ULWD, but maybe a Nikon SLWD.

Yet I dont understand the other marks next to "SLWD" such as PLAN CF, PLAN M ...

My client wants a test shot so I will go from 1X with my own lens to the final ratio and lens you will advise ..

Second question is regarding the stacking: I used to stack manually on a Contax Bellows. Do you think I can still do it at 10x or 20x or if the StackShot is now paramount ?
I dont know the aperture or Depth of Field of microscopic RMS lenses. But do you Think the Stack shot can accomodate x10 or x20 with a 0.01 mm step??

Many thanks

[enricosavazzi]

There are several aspects to consider, for example:

Is the subject two-dimensional (light projected on a flat surface) or three-dimensional (a cone of light made visible as a three-dimensional structure in smoke)? If three-dimensional, how much depth along the lens axis (i.e. neded DOF)?

Is the subject static or dynamic? Can the experimental setup keep a constant light output for long enough to allow focus stacking?

Is the emitted light intensity sufficient? Does it require a long exposure in a darkened environment?

What is the desired image resolution? Are there fine details to be recorded, like speckles or diffraction rings? Or does a low resolution suffice, perhaps making it practical to use a lower magnification and cropping in PP?

Is the view through the protection window perpendicular to the surface of the subject or oblique? Is the window itself perpendicular to the lens axis or oblique? What is the approximate thickness of the window? A thick oblique window will likely introduce several unacceptable types of aberration. Even a perpendicular thick window introduces spherical and other aberrations.