The Mosaic II imager, used at the Blanco 4-m prime focus, takes filters that are 146x146 mm and 12 mm (nominal) thick.
Focus offsets are referred to the R filter, since this is the filter we use for taking focus frames each night when the Mosaic is installed in order to monitor telescope performance.
We are (slowly) measuring these filters, let us know if there is any one you particular want to have us scan. Note that the Sloan set (griz) and the Johnson-Cousins BVR (but not I) sets should be near-identical to those at KPNO, see the KPNO Mosaic Filters.
A set of standardized filter names and IDs have been developed to
ensure proper application of astrometric solutions and real-time display
processing (as well as future archive uniformity). These official names
are listed in the Mosaic
filter list web page.
Note: The central wavelength
of narrow band filters (actually all filters, but it is very
significant for narrow band filters) is shifted
~15A to the BLUE in the f/2.87
beam of the Blanco 4m + PFADC corrector as compared to the transmission
measured in parallel
light. The central wavelengths quoated below are nominally for
when the filters used at PF, with the ~15A shift included. Furthermore,
the filter transmission curves presented below show the simulated
filter tranmission curve for the Blanco 4m + PFADC f/2.87 beam.
| Filter | Central Wavelength (Å) |
FWHM (Å) |
Focus Offset (μm) |
NOAO Code |
Status |
Transmission Curve |
Transmission Table |
|---|---|---|---|---|---|---|---|
| U | 3570 | 650 | -185 | c6001 | OK |
c6001.ps c6001.jpg |
c6001.txt |
| B |
4360 |
990 |
+10 |
c6002 |
OK |
c6002.ps c6002.jpg |
c6002.txt |
| V |
5370 |
940: |
+30 |
c6026 |
from 21 Oct 2000 |
c6026.ps c6026.jpg |
c6026.txt |
| R |
6440 |
1510 |
0 |
c6004 |
OK; filter offset ref |
c6004.ps c6004.jpg |
c6004.txt |
| I |
8050 |
1500 |
+10 |
c6028 |
from 24 May 2003 |
c6028.ps c6028.jpg |
c6028.txt |
| VR Stubbs (aka VR Supermacho) |
6100 |
2000 |
0 |
c6027 |
OK |
c6027.ps c6027.jpg c6027.jpg (OLD) |
c6027.txt |
| C (Wash) |
4000 |
1000 |
+260 |
c6006 |
OK |
c6006.ps c6006.jpg |
c6006.txt |
| M (Wash) |
5020 |
1020 |
+260 |
c6007 |
OK |
c6007.ps c6007.jpg |
c6007.txt |
| D51 (DDO) |
5130 |
154 |
-55 |
c6008 |
OK |
c6008.ps c6008.jpg |
c6008.txt |
| [OII] |
3727 |
50 |
? |
c6012 |
c6012.ps c6012.jpg |
c6012.txt |
|
| [OIII] |
4990 |
50 |
+130 |
c6014 |
OK |
c6014.ps c6014.jpg |
c6014.txt |
| Hα |
6563 |
80 |
+65 |
c6009 |
cwl, FWHM nominal |
c6009.ps c6009.jpg |
c6009.txt |
| Hα+80 |
6650 |
80 |
-35 |
c6011 |
cwl, FWHM nominal |
c6011.ps c6011.jpg |
c6011.txt |
| [SII] |
6725 |
80 |
+60 |
c6013 |
cwl, FWHM nominal |
c6013.ps c6013.jpg |
c6013.txt |
| u (SDSS) |
3600 |
400 |
+230 |
c6022 |
cwl, FWHM approx, replacement for c6021, NO RED LEAK |
c6022.ps c6022.jpg |
c6022.txt |
| g (SDSS) |
4813 |
1537 |
+30 |
c6017 |
"set #2" (in use 8/2000-) |
c6017.ps c6017.jpg |
c6017.txt |
| r (SDSS) |
6287 |
1468 |
+120 |
c6018 |
"set #2" (in use 8/2000-) |
c6018.ps c6018.jpg |
c6018.txt |
| i (SDSS) |
7732 |
1548 |
-20 |
c6019 |
"set #2" (in use 8/2000-) |
c6019.ps c6019.jpg |
c6019.txt |
| z (SDSS) |
9400 |
2000 |
-15 |
c6020 |
OK |
c6020.ps c6020.jpg |
c6020.txt |
| Bj (Tyson) |
4350 |
1650 |
? |
c6024 |
#3, on loan from A. Tyson |
c6024.ps c6024.jpg |
c6024.txt |
| I (Tyson) |
8800 |
2000 |
? |
c6025 |
cwl, FWHM approx |
c6025.ps c6025.jpg |
c6025.txt |
| White |
6500 |
5000 |
? |
c6016 |
Fused Silica |
| Filter |
Central Wavelength (Å) |
FWHM (Å) |
Focus Offset (μm) |
NOAO Code |
Status |
Transmission Curve |
Transmission Table |
| g (SDSS) |
4825 |
1380 |
? |
c6015 |
"Set #3",red cut-off a bit too red (in use < 8/2000) |
||
| V |
5370 |
940 |
115 |
c6003 |
small chip in corner (in use
< 10/2000) |
c6003.ps c6003.jpg |
c6003.txt |
| Bj |
4350 |
1650 |
? |
-- |
#1 broken... |
||
| Bj |
4350 |
1650 |
? |
-- |
#2 broken... |
||
| Old I |
8050 |
1500 |
+25 |
c6005 |
Filter damaged Nov 2002 Area covered by CCD-1 (SW corner) is unusable. |
c6005.ps c6005.jpg |
c6005.txt |
Last updated: 2006 Feb 15 by S.Points
