Long Camera Mode |
|
|---|---|
| Focal Length | 641.8 mm |
| Focal Ratio | f/4.3 (imaging), f/2.66 (anamorphic) |
| Field of View | 15.46 arcmin x 15.46 arcmin, Square |
| Vignetting | None |
| Total Detector Area | 239 arcminČ |
| Pixel Scale | 9.0 pixels/arcsec |
| Design Wavelength Range | 0.365 ”m - 1.0 ”m |
| Allowed Wavelength Range | 0.34 ”m - 1.1 ”m |
Short Camera Mode |
|
| Focal Length | 355.6 mm |
| Focal Ratio | f/2.38 (imaging), f/1.47 (anamorphic) |
| Field of View | 27.20 arcmin x 27.20 arcmin, Radiused at 36.4 arcmin |
| Total Detector Area (direct imaging) | 635 arcminČ |
| Total Detector Area (spectroscopy) | 737 arcminČ |
| Pixel Scale | 5.0 pixels/arcsec |
| Design Wavelength Range | 0.39 ”m - 1.05 ”m |
| Allowed Wavelength Range | 0.39 ”m - 1.1 ”m |
Current Long Camera Gratings |
||||||
|---|---|---|---|---|---|---|
| Ruling Density | Blaze Angle | Order | Central Wavelength | Wavelength Range | Dispersion | Dispersion |
| Lines/mm | Degrees | ”m | ”m | R/0.5-arcsec slit | A/pixel | |
| 300.0 | 4.3 | 1 | 0.665 | 0.365 - 0.974 | 2162 | 0.743 |
| 600.0 | 8.63 | 1 | 0.518 | 0.365 - 0.675 | 3491 | 0.378 |
| 600.0 | 13.0 | 1 | 0.841 | 0.684 - 1.000 | 6117 | 0.387 |
| 1200.0 | 17.45 | 1 | 0.444 | 0.365 - 0.523 | 6542 | 0.194 |
| 1200.0 | 26.7 | 1 | 0.924 | 0.846 - 1.000 | 20693 | 0.188 |
| 1200.0 | 26.7 | 2 | 0.404 | 0.365 - 0.443 | 15740 | 0.096 |
| 1200.0 | 26.7 | 2 | 0.520 (max) | 0.482 - 0.557 | 28082 | 0.092 |
| 300.0 | 36.87 | 11 | 0.336 | 0.308 - 0.364 | 20687 | 0.068 |
| 300.0 | 36.87 | 10 | 0.369 | 0.338 - 0.399 | 20687 | 0.074 |
| 300.0 | 36.87 | 9 | 0.410 | 0.375 - 0.444 | 20687 | 0.084 |
| 300.0 | 36.87 | 8 | 0.461 | 0.422 - 0.499 | 20687 | 0.094 |
| 300.0 | 36.87 | 7 | 0.527 | 0.483 - 0.571 | 20687 | 0.107 |
| 300.0 | 36.87 | 6 | 0.615 | 0.563 - 0.666 | 20687 | 0.126 |
| 300.0 | 36.87 | 5 | 0.738 | 0.676 - 0.799 | 20687 | 0.150 |
| 300.0 | 36.87 | 4 (pointless) | 0.922 | 0.845 - 0.998 | 20687 | 0.187 |
Short Camera Grisms |
||||||
| 200.0 | 15.0 | 1 | 0.66 | 0.39 - 1.0 | ? | 2.037 |
| 300.0 | 17.5 | 1 | 0.67 | 0.39 - 1.0 | ? | 1.341 |
| 600.0 | 34.0 | 1 | 0.77 | 0.56 - 1.0 | ? | 0.583 |
| 600.0 | 34.0 | 2 | 0.39 | 0.39 - 0.52 | ? | 0.291 |
Notes:
A 1200/36.8 grating exists from Richardson Grating Laboratory.
The 600 l/mm grism uses a very heavy lead glass. Transmission in
the blue in second order is very poor.
Here is a web page which computes Long Camera grating angles.
Filters are 165 mm x 165 mm square, 12 mm thick (nominal). The filter frames can be modified to allow larger filters, while smaller filters may require an adaptor (most likely a cutout from a 1/2" aluminum plate). Click here for more complete filter specifications.
Clear Spectroscopy Filters for both cameras
Johnson/Cousins/Bessell BVRI. I-band has a red cutoff to match
that used by Landolt at CTIO.
There are some plans for a third party to purchase a refelctive
U-band filter for the f/4 camera.