Previous Article Next Article Table of Contents
New Camera on 1.5-m Bench-Mounted Echelle...(1Mar95) Gives Resolution of 98,000 (from CTIO, NOAO Newsletter No. 41, 1 March 1995) A new 750mm folded Schmidt camera has been permanently installed on the 1.5-m bench-mounted echelle spectrograph (BME). The 750mm camera has quartz optics with broad-band anti-reflection coatings and offers excellent transmission and image quality from the atmospheric UV cutoff to one micron. It replaces the 4-m echelle spectrograph Long Cameras which previously were used on this instrument. This new camera is now the only camera available with the BME. This change greatly simplifies support of the BME as well as offering 27% greater resolution than the previous camera because of its longer focal length. The new camera was especially designed to match the echelle image to the size of the large format Tek 2K X 2K CCD with 24 micron pixels. The full free spectral range is imaged onto the CCD out to about 9500 . In its first use, with a 30 micron slit on the fiber tail, the BME produced excellent images on an 800 X 800 TI CCD and achieved a measured resolution of 98,000 at 2 pixels FWHM. Because the CCD is not flat, image size varied over the surface of the TI, with the best images measuring significantly less than two pixels FWHM. However, the TI CCD has now been retired, and the new camera is currently available only with a Tek 2K X 2K CCD. This combination can be expected to give a maximum resolution of approximately 60,000 with the 45 micron slit. Higher resolutions will await the availability of a CCD with smaller pixels. An 800 X 1200 Loral CCD with 15 micron pixels is expected to be put into service later this year. Resolution, noise, and potential availability of this chip are not known at this time. Please contact either of us or look on the 1.5-m BME section of the CTIO Mosaic page for the latest information. T. Ingerson, N. Suntzeff
Previous Article Next Article Table of Contents