Collimating a Laser collimator

Ever wonder if that inexpensive laser collimator is really doing what it should? I never really trusted them, therefore I put mine on test one day. The first thing I had to build was V-shaped holder made out of wood, to prevent the collimator from moving around during tests.

V-shaped holder

Next I nailed the holder on to the wooden table to stabilize it and put the turned on collimator in v-shaped notch. 5 meters away (farther is better) where the laser beam was shining on the wall I attached a white paper for markings. Now rotate the laser collimator and see if the beam is making a circle or it stays a dot. If it stays in one place, your collimator is in perfect alignment. As you can see from the markings on the picture, my laser beam was making a circle. Using the two small allen adjustment screws at the back of the collimator move the beam so that it is pointing in the center of the marked circle and rotate it again. Repeat this until the beam remains in place while rotating the collimator. It took me about 5 iterations.
That’s it. You have successfully realigned you laser collimator, now use it with confidence for aligning your telescope optics.

Black markings on paper clearly show that my laser beam was making a circle.


V-shaped holder in action, preventing the collimator to move around.

Building weather shelter

The general purpose of a weather instrument shelter is to protect the monitoring equipment inside which may consist of any number of items such as thermometers, hygrometers,etc from direct sunlight, wind & precipitation. It is important that weather instruments inside the unit have adequate natural ventilation. The double sloping roof with airflow in between roof panels should face direct sunlight.
My shelter is based on the plan made by our National Meteorological Service.

frame and laths
Sawing finished, proceeding to assembly.

frame and laths glued together
Gluing wood

Every side must have double laths fixed at right angles. The right angles prevent the wind blowing on thermometer, so it is measuring real air temperature and not wind chill (felt air temperature on exposed skin due to wind). The laths should not be to close together to ensure adequate ventilation.

All the laths glued to the frame.

painted and ready for assembly
Painted and ready for final assembly.

All the parts painted white and ready for assembly. White colour increases albedo and prevents the Sun to heat up inside of the shelter, that would result in incorrect detector readings.

assembled
Finally everything assembled together and ready for use.