Back to forums

Pixinsight Error Msg in WBPP Flat vs Dark exposure?

ZWO ASI294MC Pro Processing Calibration Deep Sky
6 replies•133 views
RICK avatar
RICK avatar
This is new, never saw this before.  My Flats will always have a different exposure time vs Darks.  My Darks and Lights are both 180s.  The flats are 12.5s.

 

Any idea what's going on?
ASI294MC Pro.
Of Note, I recently switched from FITS to XISF.  Flats and Lights are XISF.  Darks are from an older library in FITS.


andrea tasselli avatar
andrea tasselli avatar
Uncheck "Dark" in the Flat tabs. Use "Bias" instead and add those bias frames. Either one or the other must be there and flat-darks have the same exp. length of the flats (which are waaaaaaaaaaaaaaaaaaay too long, btw).
RICK avatar
RICK avatar
andrea tasselli:
Uncheck "Dark" in the Flat tabs. Use "Bias" instead and add those bias frames. Either one or the other must be there and flat-darks have the same exp. length of the flats (which are waaaaaaaaaaaaaaaaaaay too long, btw).

I ended up shooting Dark-Flats as BIAS frames.

WRT flat exposure, the ASI-294MC Pro is NOTORIOUS for producing bad flats with anything under 3 second exposure.
andrea tasselli avatar
andrea tasselli avatar
RICK:
WRT flat exposure, the ASI-294MC Pro is NOTORIOUS for producing bad flats with anything under 3 second exposure.


Absolutely NOT TRUE. My flats are never ever ever ever ever more than 1s. And they never fail.
Oscar avatar
Oscar avatar
RICK:
WRT flat exposure, the ASI-294MC Pro is NOTORIOUS for producing bad flats with anything under 3 second exposure.


by "bad", do you mean they're too dim, or something else?

how are you taking flats?
Niels_L avatar
Niels_L avatar
RICK:
My Darks and Lights are both 180s.  The flats are 12.5s.

WBPP takes your darks as flat-darks and thus the exposure time does not correspond.  Take some darks at 12.5s to use as dark-flats.
Concise
JohnAdastra avatar
JohnAdastra avatar
Having darks to match the flats is always best. My cheat is to have a series of dark masters - 0.5, 1, 5 ,10, 15, 20, 30s, then use select the closest which is just greater than the flat exposure and check off optimize master dark. This should be close enough and much better than optimizing the longer darks that match your lights.
Helpful Concise