Photometric slit 23/200µm

This photometric slit for Alpy 600 and UVEX spectroscopes (to be used only with the guiding module), contains two different slit widths (in line with each other). The narrow slit (23µ) improves the resolution of the Alpy 600 or the UVEX. The wide slit (200µ) completes this observation with a spectrum that integrates all the star’s light – enabling photometric measurement.

The slit is divided into two parts: a narrow 23µm slit (for maximum resolution) and a wide 200µm slit (for photometry).

See Christian Buil’s web pages on this method:
http://www.astrosurf.com/buil/calibration2/method.htm
http://www.astrosurf.com/buil/calibration2/absolute_calibration.htm
http://www.astrosurf.com/buil/alpy600/photometric_slit.htm