Extreme macro – microchips
Every so often we get asked if we can photograph an unusual object.
It’s something I enjoy doing, since it gives me a chance to experiment and perfect new skills.
It also has the advantage of being paying work ;-)
This followed on from the ‘homemade’ macro lens I wrote about a while ago.
Whilst the extreme macro lens allowed me to show writing on the surface of a 0.75mm x 0.75mm chip, the depth of field was miniscule.
What about the comparatively huge 2.1mm x 2.0mm chip to the right?
I needed an oblique angle shot, so the simple approach of putting the chip onto a decent flat bed scanner wouldn’t work.
One solution is to use focus stacking, but unless you have (or have constructed) a Telecentric lens, then the image changes size as you move the camera focal plane from front to back (either by moving the camera with a focus microadjuster plate or focusing the lens). This can make stacking difficult, even with specialist software.
I could use our converted 5×4 camera with movements, but it is rather unwieldy, even with the fairly hefty studio stand I use for support.
The Canon TS-E90mm does work well with extension tubes, and here it is, looking at a group of two chips.
Canon 1Ds mk3, TS-E 90mm lens with 65mm of extension tubes. Some 3 degrees of tilt to get more of the chip in focus. Canon MT-24EX macro flash, with old slide box covers added as diffusers.
The Canon MT-24EX is set in manual mode, whilst the CFL light panels at either side give enough light to use liveview (I got our used MT-24EX in the UK from MPB. who also sourced the TS-E90 for us several years ago)
You can see a white business card mounted behind the chips as a reflector – it’s like setting up a studio in a dolls house…
With such a setup, the combination of extension tubes and tilt, make achieving sharp focus a matter of experimentation. If you’re unfamiliar with using tilt this way I’ve written an article about focusing with tilt that may be of interest.
Whilst I don’t think my eyesight would appreciate too much work like this, it’s great to be able to supply just the images the client wanted, and add another feature to our range of product photography work.
See also my quick look at the MP-E65 macro lens from Canon