Wednesday, April 28, 2010

First Results with Model 163 Microscope

Thanks to the nice people at the Maker Shed of Make Magazine we have an awesome new microscope to play with.

To prove the point that you don't need automation in order to capture a GigaPan style mosaic of images (assuming you have a good eye, and patience :-) I took the following gigapan of part of a 6 inch machinist's ruler. The numbers are tenths of an inch, and the hash marks are hundredths of an inch.

View the full image at

This image was taken with the 4x objective, which normally has a 40x magnification, and a 4.5mm Field of View. The SLR camera adapter adds 2.5x of magnification, to 100x, and each frame has a 1.8mm field of view.

All thanks to Dan Woods and Rob Bullington at Make Magazine for giving us a huge discount on a 'Compound Oil Immersion Microscope model 163' It is like their model 162 but with a 3rd viewing port which comes straight up.

We also got a SLR Photo Adapter, with a 2.5x magnifying lens which ends in a T-Mount, and a T-Mount adapter for the Canon T2i camera.

The result is a comparatively inexpensive instrument which has a non-motorized xy stage and non-motorized focus knob. We are working to adapt the XY and Z axis to be controlled by stepper motors with an arduino running a slight variant of the G-Code CNC machine code from the Makerbot/RepRap code base (the variation is just ripping out some code and libraries which we don't need in order to make it compile a little easier).


Monday, April 19, 2010

micro focus stacking tests

This weekend I managed to start playing around with focus stacking, using Zerene Stacker. I seem to be getting mixed results from the final output images. There are however quite a few variables to play with, modifying depth of field through aperture size both on the camera and the microscope, varying number of images in a stack, light conditions, etc. The images above show the preliminary results. They were all imaged using the same aperture settings, about mid setting on the microscope and 6.3f on the camera. Each set of images contains the final stacked image on the right and two of many (40-50) images used to create the final stack, giving some sense of the obstacle of a reduced depth of field. These images were taken at roughly ~200x, ~1000x, and ~2000x magnification. It's neat to compare these images to those taken with the SEM in the gigapan below:

Thursday, April 15, 2010

imaging the imager

The subject of this micro-gigapan is the optical sensor of a canon powershot G1. The chip is about 8mm long and 6mm wide. While the entire length of the chip was captured, only a small portion of the width was imaged due to the highly repetitive pattern of the light sensors.

The focus stacking feature has still yet to be implemented on this microscope. As such the chip had to be very level with imaging plane. The chip was leveled using a two degree of freedom rotation stage.