Focus Stacking with a Raspberry Pi – initial trials
I have had some time to play with my macro focus stacker recently, having accumulated some specimens to practice on. And so I have found that I need to acquire a new set of skills besides those of macro photography, namely the mounting and preparation of the insect specimens, and the cleaning thereof. They aren’t exactly dirty per-se, but they have microscopic particles on their eyes and in their hairs that catch the light and/or are noticeable in the image and can be a distraction – awfully difficult to remove, even in Photoshop!
And it can take ages to get everything lined up exactly as you want, bearing in mind that one is dealing in fractions of a millimeter. The whole business of mounting and arranging is very fiddly, time consuming and frustrating. If you want a nice clean symmetrical head on image you will have to do some work for it!
This shot is of a green bottle fly (not a blue bottle). It was taken with a Nikon 50mm f2.8 enlarging lens reversed onto a Minolta MD 135mm lens with adapter on a Sony NEX7 camera. This gives a magnification of about 2.5. The stacking increment was 100 micrometers. I used Zerene Stacker for processing.
I have realised I need to do a lot more work on the lighting, as my light box is giving too much back lighting and not enough front lighting. Also I need a better way of providing a coloured back drop. I have an old pc monitor that I may experiment with, by using it as a back drop driven from a pc running photoshop or something like that, and displaying a suitably coloured screen. I am not sure if it will be bright enough, but we will see!