We are currently formulating plans for continued use of the IFPS. Because the 2.4-m Hiltner telescope has an f/7.5 beam compared to the f/17.5 beam of the 1.8-m Perkins, deploying the IFPS at MDM would necessitate extensive redesign of the optics and the optical bench and mounting surfaces. Given other projects with higher priority, it was decided that it would be impractical to begin what is essentially the design and building of a new IFPS at the present time. We are exploring other non-MDM options, and would be interested in hearing ideas. Please contact Richard Pogge (email@example.com) for more information.
It uses four Queensgate Instruments ET-50 etalons providing spectral resolutions of:
We started with a Texas Instrument 800x800 CCD (cast-off WF/PC-1 CCD), but have recently installed a new Loral 1200x800 CCD thinned and coated in Mike Lesser's CCD Lab at the Steward Observatory. This detector boasts excellent cosmetics, low noise (7e- RMS), and high DQE (95% Peak QE at 6500Å - Thanks Mike!).
A paper describing the IFPS (Pogge et al. 1995, PASP, 107, 1226) is available:
View of the IFPS optical bench, showing the optics, calibration lamps, and filter-wheel assembly (200Kb GIF). An annotated version is available.
Instrument Schematic (41Kb PostScript)
Optical Layout (29Kb PostScript)
Side view of the IFPS on the 1.8m Telescope
View of the IFPS on the 1.8m Perkins Telescope, Flagstaff, AZ, with an astronomer shown for scale.
Ionization map of the Ring Nebula (21Kb GIF), composed of three emission-line images taken through narrowband filters isolating particular bright emission lines. Coding: Red=[OI]6300, Green=[OIII]5007, Blue=HeII 4686
Also available as a 408KB 24-bit TIFF
Ring Nebula [S II] Data (41Kb PostScript), a combination flux and spectrum grid in a sub-window.
Updated: 1998 January 1 [rwp]