[M]: OT: Building a dark frame library for ST-7
| Subject: | [M]: OT: Building a dark frame library for ST-7 |
| From: | Michael D. Sparks |
| Date: | Sun Aug 01 11:44:17 1999 |
I recently started building a dark frame library for my ST-7. Most of the
entries are for long exposures so I dont spend half of my imaging sessions
waiting for dark frame exposures. I am also cataloging the dark frame
exposures in 2 deg C increments. In other words I have an 1800 sec dark
frame at 0 deg C, -2 deg C, -4 deg C and so on. Im still not sure if this
is the way to go vs. taking a dark frame for every light frame. However,
it is something I can do during the day or on cloudy nights so it really is
not costing me much time.
The ST-7 has three degrees of antiblooming low, medium, and high. My
manual says that the degree of antiblooming affects the dark current. My
manual also recommends building the dark frame library. But it doesnt
tell me what parameters to build the library on other than temperature and
time. Does anyone know if I should include in my library the degree of
antiblooming? In other words if I have a library for 0, -2, and -4 deg C
exposures, instead of having 3 1800 sec dark frames do I need 9
(1800 sec @ 0 deg C, low AB; 1800 sec @ 0 deg C, med. AB; 1800 sec @ 0 deg
C, hi AB; 1800 sec @ -2 deg C low AB; 1800 sec @-2 deg C med. AB;...).
Also are there any other parameters that affect the dark frame that I
should use when building and cataloging my library?
Thanks
Mike
entries are for long exposures so I dont spend half of my imaging sessions
waiting for dark frame exposures. I am also cataloging the dark frame
exposures in 2 deg C increments. In other words I have an 1800 sec dark
frame at 0 deg C, -2 deg C, -4 deg C and so on. Im still not sure if this
is the way to go vs. taking a dark frame for every light frame. However,
it is something I can do during the day or on cloudy nights so it really is
not costing me much time.
The ST-7 has three degrees of antiblooming low, medium, and high. My
manual says that the degree of antiblooming affects the dark current. My
manual also recommends building the dark frame library. But it doesnt
tell me what parameters to build the library on other than temperature and
time. Does anyone know if I should include in my library the degree of
antiblooming? In other words if I have a library for 0, -2, and -4 deg C
exposures, instead of having 3 1800 sec dark frames do I need 9
(1800 sec @ 0 deg C, low AB; 1800 sec @ 0 deg C, med. AB; 1800 sec @ 0 deg
C, hi AB; 1800 sec @ -2 deg C low AB; 1800 sec @-2 deg C med. AB;...).
Also are there any other parameters that affect the dark frame that I
should use when building and cataloging my library?
Thanks
Mike
