A simple photometer

First, consider a very simple 1-channel UBV photometer. Let us assume a rather minimal instrument: no cooling or temperature regulation, and simple DC photometry. This resembles the instrument with which the UBV system was first set up. Here is the table:

Descriptor values: NFILTCAR = 1

NDETS = 1

FILTSTAT = DOME

FILTCAT = ' ' (blank string)

CONDITION = AVERAGE

Passband sub-table  

NBAND BAND FILTCODE_1 REDLEAK RLTYPE MAKER

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

1 U 3 MEASURED LOOSE CORNING

2 B 1 IGNORED

3 V 2 ABSENT

4 URL 4 ABSENT

Detector sub-table

NDET DET SNUMBER MODE COOLING

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

1 PMT S-4 DC NONE

As there is only one detector, we need not include the NDETUSED column.

Descriptor values: NFILTCAR = 2

NDETS = 1

FILTSTAT = DOME

FILTCAT = ' ' (blank string)

CONDITION = AVERAGE

Passband sub-table  

NBAND BAND FILTCODE_1 FILTCODE_2 NDVALUE REDLEAK RLTYPE MAKER

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

1 u 10 1.000 MEASURED CEMENTED SCHOTT

2 v 20 1.000 BLOCKED

3 b 30 1.000 BLOCKED

4 y 40 1.000 BLOCKED

5 uND 11 9.897 MEASURED CEMENTED SCHOTT

6 vND 21 9.763 BLOCKED

7 bND 31 9.674 BLOCKED

8 yND 41 9.695 BLOCKED

9 DARK any 1

Detector sub-table

NDET DET SNUMBER MODE DEADTYPE DEADTIME DEADTIMEERROR COOLING DETTEMP

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

1 PMT QBIALKAI PC EXTENDING 6.74E-8 4.2E-9 REGULATED 273.