#207 closed defect (fixed)
psExposure's "Derived quantities"
| Reported by: | Owned by: | Paul Price | |
|---|---|---|---|
| Priority: | high | Milestone: | |
| Component: | PSLib SDRS | Version: | unspecified |
| Severity: | normal | Keywords: | |
| Cc: |
Description
There are about a half-dozen attributes in the psExposure struct labelled as
'Derived Quantities'. Does psExposureAlloc suppose to derive these values from
the other inputs, and if so, how?
Change History (4)
comment:1 by , 22 years ago
| Status: | new → assigned |
|---|
comment:2 by , 22 years ago
| Resolution: | → fixed |
|---|---|
| Status: | assigned → closed |
ADD says use sla_PA for parallactic angle. Alternatively,
tan(PA) = sin(HA) / [ tan(lat) cos(dec) - sin(dec) cos(HA) ]
where PA is the parallactic angle, HA is the Hour Angle, lat is the observer's
latitude, and dec is the declination of the object.
Reference: http://groups.yahoo.com/group/guide-user/message/3753
comment:3 by , 22 years ago
| Keywords: | VERIFIED added |
|---|
Closing subsequent to release of SDRS-08, ADD-07.
comment:4 by , 22 years ago
| Keywords: | VERIFIED removed |
|---|
Note:
See TracTickets
for help on using tickets.
The local sidereal time, lst, comes from psTimeToLST.
posAngle comes from applying an offset to the rotator angle.
The parallactic angle is the angle to the horizon --- I will get a formula.
Airmass comes from SLALib's function sla_AIRMAS.
Parallactic factor hasn't been specified yet --- ignore for now.