2. Moon distance

The plot below shows sky counts/pixel above bias versus the Moon distance, at the wavelength 5000 Å with the Moon illumination of 98%.

A target acquision is still quite easy at 9 degrees away from the nearly full Moon, but gets very difficult at 4 degrees away from the nearly full Moon.

3. Acceptable wavelength ranges

The idea of this test is to check the range of Angstroms you can move the central wavelength of the original setup, for the setup to be still acceptable. This test is useful in situations when observers want to change the central wavelength during the night or in cases when there are little lines in a configuration and you have to move the central wavelength to be able to perform the setup. The following tests have been performed:

Date	CCD	Grating	Central Wavelength	Acceptable range	Note
20171129	Red+2	H1800V	6400	± 700 Å
20171129	Red+2	R300V	5750	> +2300 Å	Both upper and lower limits should be still measured.

Top | Back

---

Contact:  (IDS Instrument Specialist) Last modified: 05 June 2018