Jump to content


Flats with Mono camera

Recommended Posts


I'm just getting back into imaging having been unable to do it for a while due to ill health.

I'm using a Zwo 1600MM cool camera with filter wheel and 2" filters.  The filter wheel currently has the following filters in it - L, R,G,B, Ha.

If I'm taking L, R, G, B, images is it alright to use the flat from the Luminance filter for the R,G,B images or should I take a separate flats for each specific filter.

I'm happy that my filters are clean and as they are contained within the sealed filter wheel then my view is the Luminance flats will be alright to use for the other filters as the Luminance flat will show up any dust bunnies etc in my optical train.

Is this alright to do as it will save some time.



Link to post
Share on other sites

I'm not 100% as I have only attempted colour to date, but I think the answer would be to take flats for each filter.  The reason being is amongst other things, flats correct for dust in the setup.  Therefore, if you have any particles on one of your colour filters that will appear on the light frames, you would need to correct this by taking flats using the same filter.


Link to post
Share on other sites

And if we're being really picky, unless the filters are actually parfocal the vignetting will be slightly different between filters, since the focuser had to move.

I just set up a standard sequence, one for narrowband and one for LRGB, and run it at the end of every session (well, every session when I'm not too blind from sleep deprivation to remember). Ten flats takes maybe a minute, most of which is download time. So, ten minutes to do 20 on all 4 channels -- probably less.

Heck, if I pulled the scope out of the saddle and propped the LED panel up against the end instead of pointing at the zenith and laying the panel on top...by the time I had the mount torn down and put away the flats would be done.

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    No registered users viewing this page.

  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.