Filters and Throughputs

Calculated filter characteristics and transmission curves are given below. All are based on standard reflectivity or transmission data for various surfaces, unless a part specific curve was provided by the manufacturer. No transmissive optics (ADCs, etc) are currently accounted for.

The atmosphere is included in the numbers presented in the table below. BTRAM was used to calculate the atmospheric transmission for LCO, and the below values assume a zenith distance of 30 degrees and 5.0 mm PWV. A version of each curve is provided without the atmosphere contribution, which can then be combined with the atmosphere of your choice.

None of these values have been verified on sky. They should be used for planning purposes only.

Visible Science Cameras

Filters in the visible science cameras.

camsci1

Filter

WFS B/S

Sci BS

\(\lambda_0\) [mum]

\(w_\mathrm{eff}\) [mum]

\(\mathrm{QE}_\mathrm{max}\)

\(F_0\) [photon / sec]

Files

H-alpha Cont.

H-alpha/IR

H-alpha

0.668

0.009

0.22

\(3.8\times10^{9}\)

atm noatm

ip

65/35

ri

0.764

0.120

0.11

\(2.1\times10^{10}\)

atm noatm

zp

65/35

ri

0.908

0.130

0.08

\(1.3\times10^{10}\)

atm noatm

rp

65/35

open

0.615

0.110

0.23

\(6.1\times10^{10}\)

atm noatm

ip

65/35

open

0.762

0.126

0.11

\(2.2\times10^{10}\)

atm noatm

zp

65/35

open

0.908

0.131

0.09

\(1.3\times10^{10}\)

atm noatm

CH4

65/35

50/50

0.875

0.026

0.04

\(1.3\times10^{9}\)

atm noatm

rp

65/35

50/50

0.615

0.112

0.11

\(2.9\times10^{10}\)

atm noatm

ip

65/35

50/50

0.762

0.126

0.06

\(1.1\times10^{10}\)

atm noatm

zp

65/35

50/50

0.908

0.130

0.04

\(6.3\times10^{9}\)

atm noatm

camsci2

Filter

WFS B/S

Sci BS

\(\lambda_0\) [mum]

\(w_\mathrm{eff}\) [mum]

\(\mathrm{QE}_\mathrm{max}\)

\(F_0\) [photon / sec]

Files

H-alpha

H-alpha/IR

H-alpha

0.656

0.009

0.23

\(3.5\times10^{9}\)

atm noatm

gp

65/35

ri

0.527

0.041

0.24

\(3.1\times10^{10}\)

atm noatm

rp

65/35

ri

0.613

0.106

0.23

\(5.9\times10^{10}\)

atm noatm

CH4 Cont.

65/35

50/50

0.923

0.023

0.04

\(9.6\times10^{8}\)

atm noatm

gp

65/35

50/50

0.525

0.044

0.13

\(1.9\times10^{10}\)

atm noatm

rp

65/35

50/50

0.614

0.109

0.12

\(3.3\times10^{10}\)

atm noatm

ip

65/35

50/50

0.762

0.126

0.06

\(1.1\times10^{10}\)

atm noatm

zp

65/35

50/50

0.909

0.132

0.04

\(6.7\times10^{9}\)

atm noatm

WFS

Filters in the main WFS.

WFS B/S

Filter

\(\lambda_0\) [µm]

\(w_\mathrm{eff}\) [µm]

\(\mathrm{QE}_\mathrm{max}\)

\(F_0\) [photon / sec]

Files

H-alpha/IR

open

0.837

0.205

0.20

\(5.3 \times 10^{10}\)

noatm atm

65/35

open

0.791

0.296

0.08

\(4.2 \times 10^{10}\)

noatm atm

LOWFS

Filters in the low-order WFS.

Atmosphere

Atmospheric transmission curves.