SDSS Filters

We present the transmission curves of the SDSS filters (u', g', r', i', z') and describe

the corresponding specifications. Five sets of SDSS filters including those for the main

imaging camera, Monitor Telescope (now Photometric Telescope), and USNO 40-inch telescope

were manufactured by Asahi Spectra Co. Ltd. in Japan according to the specifications

given here. New orders for the SDSS filters can be placed directly with Asahi Spectra,

Co. Ltd. Contact address is given in the "Specifications".

We also present the numerical values of transmission measured for the SDSS filters for

MT/PT, USNO 40-inch telescope, and the 2.5m telescope.

Inquiries on this Web page should be addressed to Kazuhiro Shimasaku.

email: shimasaku@astron.s.u-tokyo.ac.jp

(JPG: Japanese Paticipation Group to the SDSS).

-----------------------------------------------------------------------

Specifications and Designs

Original Specifications (1995)

Revised Designs (Oct 4, 2000 by T. Ichikawa; preliminary)

u' band transmission (film x color glass)

Film transmission

Color glass transmission is overlaid on film transmission

g' band transmission (film x color glass)

Film transmission

Color glass transmission is overlaid on film transmission

r' band transmission (film x color glass)

Film transmission

Color glass transmission is overlaid on film transmission

i' band transmission (film x color glass)

Film transmission

Color glass transmission is overlaid on film transmission

z' band transmission (film x color glass)

Film transmission

Color glass transmission is overlaid on film transmission

-----------------------------------------------------------------------

Filters for SDSS Photometric Telescope (PT) (Aug 17, 2006)

u' transmission (with red leak)

mirror (two surfaces)

Miscellaneous data for filters manufactured in 1995-1998.

Fig of transmission (for MT) (measured in 1995)

3-inch filters for MT (measured in 1995)

3-inch filters for USNO (measured in 1995)

57mm filters for 2.5m photometric camera (measured in 1995,1998) (Apr 14, 2000)

u' filters (fig)

g' filters (fig)

r' filters (fig)

i' filters (fig)

z' filters (fig)

Transformation Law between 2.5m and MT. I (May 15, 2000)

2.5m responses: measured by Doi (May 2000)

MT responses: defined in 1996 (T. Ichikawa)

A note on u'(MT) response.

When I calculate u'(2.5m)-u'(MT) color, I remove the red leak part from the original

u'(MT) response data, because Doi did not measure red leaks for u'(2.5m).

(It is very difficult and takes a long time to measure it.)

u(2.5m)-u(MT) vs g(MT)-r(MT)

u(2.5m)-u(MT) vs g(MT)-r(MT) (zoom-up)

g(2.5m)-g(MT) vs g(MT)-r(MT)

g(2.5m)-g(MT) vs g(MT)-r(MT) (zoom-up)

r(2.5m)-r(MT) vs g(MT)-r(MT)

r(2.5m)-r(MT) vs g(MT)-r(MT) (zoom-up)

i(2.5m)-i(MT) vs g(MT)-r(MT)

i(2.5m)-i(MT) vs g(MT)-r(MT) (zoom-up)

z(2.5m)-z(MT) vs g(MT)-r(MT)

z(2.5m)-z(MT) vs g(MT)-r(MT) (zoom-up)

u(2.5m)-u(MT) vs u(MT)-g(MT)

u(2.5m)-u(MT) vs u(MT)-g(MT) (zoom-up)

i(2.5m)-i(MT) vs r(MT)-i(MT)

i(2.5m)-i(MT) vs r(MT)-i(MT) (zoom-up)

z(2.5m)-z(MT) vs i(MT)-z(MT)

z(2.5m)-z(MT) vs i(MT)-z(MT) (zoom-up)

Transformation Law between 2.5m and MT. II (Jun 15, 2000)

2.5m responses: measured by Doi (May 2000)

MT responses: defined in 1996 (T. Ichikawa)

The u'(MT) response includes the red-leak part.

(u-g)(MT) vs (u-g)(2.5m)

[(u-g)(2.5m)-(u-g)(MT)] vs (u-g)(2.5m)

[(u-g)(2.5m)-(u-g)(MT)] vs (u-g)(2.5m) (zoom)

(g-r)(MT) vs (g-r)(2.5m)

[(g-r)(2.5m)-(g-r)(MT)] vs (g-r)(2.5m)

[(g-r)(2.5m)-(g-r)(MT)] vs (g-r)(2.5m) (zoom)

(r-i)(MT) vs (r-i)(2.5m)

[(r-i)(2.5m)-(r-i)(MT)] vs (r-i)(2.5m)

[(r-i)(2.5m)-(r-i)(MT)] vs (r-i)(2.5m) (zoom)

(i-z)(MT) vs (i-z)(2.5m)

(i-z)(MT) vs (i-z)(2.5m) (zoom)

[(i-z)(2.5m)-(i-z)(MT)] vs (i-z)(2.5m)

[(i-z)(2.5m)-(i-z)(MT)] vs (i-z)(2.5m) (zoom)

Atmospheric transmission adopted for the above calculations (Sep 4, 2000)

(extinction = 1 - transmission)

transmission for sec(z)=1

Transformation Law between 2.5m and MT. III (Sep 5, 2000)

2.5m responses: measured by Doi (May 2000)

MT responses: defined in 1996 (T. Ichikawa)

[(g-r)(2.5m)-(g-r)(MT)] vs (g-r)(MT): stars + power-law SEDs

[(r-i)(2.5m)-(r-i)(MT)] vs (r-i)(MT): stars + power-law SEDs

Transmission of 2-inch test filters: Figure (Sep 9, 2000)

Transmission of 2-inch test filters: Data (Sep 25, 2000)

g' (vacuo; ~24.5C)

g' (air; ~29.3C)(preliminary)

Transmission of 2-inch u test filter: Data (Oct 3, 2000)