Jump to content
Welcome to Backyard Astronomy Space - please register to gain access to all of our features. Click here for more details. ×
SmallWorldsForum Microscopy and macro photography - a companion forum to BYA ×

Multi Session Imaging


paulgrover68

Recommended Posts

Not sure if this is the right section, but I am sure one of the excellent mods will move it if needed.

Until recently I have been a single night imager. However clouds and the rotation of the planet can stop me getting all the data I want.

Plate solving has made it really easy for me to return to a target and point exactly at where I was during the last session. 

So I plan image over a couple of nights.

But...

How do I process the data?

One night is easy - Lights, Darks, Flats, Bias + DSS = photoshop fun.

Imaging on different nights will require different flats... so do I stack different nights separately? Do I combine  the resultant TIFFs  in photoshop?  Do I stack the TIFFs in DSS? I'm just kinda guessing!

 

I've seen file groups in DSS, but there seems to be not a lot of guidance on using them.

 

So what so you guys recommend?

  • Like 1
Link to comment
Share on other sites

Do you retake your calibration frames each session? I'm pretty lazy and tend to keep mine as long as they still work or I rotate the camera.

So unless I change any of my calibration frames I just process as normal. 

  • Like 1
Link to comment
Share on other sites

I think that the answer depends on your setup.

When I an doing narrowband I don't need "fresh" flats.  I'm currently using flats that I took last year.

If I am doing LRGB, then I need flats between every filter change.  For whatever reason, I don't see any effects of dust bunnies with the NB filters.

Flats also seem much more important when I image with my Tal200, than when I image with my FSQ106.  I've no idea if this is due to the different focal lengths.

I shoot darks about once a year - maybe less.  I don't use bias at all - preferring flat darks for my flat frames.

 

  • Like 1
Link to comment
Share on other sites

Posted by: @paulgrover68

Imaging on different nights will require different flats.

As long as you don't rotate your camera, or change your setup, flats can be used without the need to take fresh ones. I have used flats for weeks with no problem.

  • Like 2
Link to comment
Share on other sites

Posted by: @Wyvern

I'm pretty lazy and tend to keep mine as long as they still work or I rotate the camera.

Same here. I take my image train off the mount after each session, and don't touch anything, hence no need to take flats every night.

Link to comment
Share on other sites

I often keep calibration frames 6 months or more, only taking new ones when the configuration changes.

The OTA etc stays on the mount unless I'm doing some major work on it.

  • Like 1
Link to comment
Share on other sites

Generally I've been shooting fresh flats after every session - just part of the routine I do.  While I usually take the camera off, I could always leave it in place.  

For the way tend to work (one target at a time) I'd not be moving focus or camera until done. So that actually makes life super easy.

The bonus is not having to do multiple flats... I hate shooting flats.

Thanks!

Link to comment
Share on other sites

My imaging rig stays on the mount unless I have a problem to sort out.  Unless I change something the same flats last over multiple nights and multiple objects.

Link to comment
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
  • Welcome to Backyard Astronomy Space - please register to gain access to all of our features

    Once registered you will be able to contribute to this site by submitting your own content or replying to existing content. You will also be able to customise your profile, receive reputation points for submitting content, whilst also communicating with other members via your own private personal messaging inbox. 

     

    This message will be removed once you have signed in.

  • Tell a friend

    Love The Backyard Astronomy Space? Tell a friend!
  • Topics

×
×
  • Create New...