Help with stacking plz

[Mirrorgirl]

Hi there

Just wondered if I took s bunch of 30 seconds exposures of the pleades sorry about spelling,.. and then another day took some more on same target..... could you put both of them together and stack them?

[pakarinen]

From what I’ve read, yes, you can. I’ll defer to the experts here though.

[JayTee]

The short answer is yes. Also the long answer is yes. If the image particulars are the same eg. scale, ISO then you can stack them all together. If some element is different for example different ISO's then you can stack each ISO separately and then take the results from those separate stacks and stack them into a single image.

[Mirrorgirl]

When I get the results from those seperate stacks because I have a bunch at ISO 400 and then sum at ISO 800 .. would I just get the final image of both and stack them sorry if this sounds silly I just don't know what to do next

[Juno16]

Are you using DeepSkyStacker?

If you are, you can add your lights and any calibration files to the Main Group (main window as you usually do).

Then, look at the bottom of the window and you will see that after you add files, another tab appears next to the "Main Group" called Group 1. Select that tab and add your other lights/calibration files with different exposure times or iso to that group.

Then process as usual.

[Mirrorgirl]

Thank you I will try

[bobharmony]

Are you using DeepSkyStacker?

If you are, you can add your lights and any calibration files to the Main Group (main window as you usually do).

Then, look at the bottom of the window and you will see that after you add files, another tab appears next to the "Main Group" called Group 1. Select that tab and add your other lights/calibration files with different exposure times or iso to that group.

Then process as usual.

One note about Jim's excellent explanation - DSS files that get added to the main group are used in all the groups that get created, so it is not the best place to put one set of lights if using multiple groups, as those lights will get processed in each stack. When using multiple groups the "Main" group is a great place for bias frames, or dark flats if you are using them. Group1, Group2, etc would contain the lights and darks for each session.

Or if as JT says you are processing just a bunch of lights from different nights, just throw them all into the Main group and let DSS sort out any sort of offset and rotation differences between the two nights. Sometimes simpler is better.

Bob

[Juno16]

@bobharmony

Thanks for the clarification Bob! I didn’t realize that!

[chris_g]

Yes, you can. I've done it with that target in particular. I plate solved the image from the first night then did a goto. Keep in mind that you're iso and exposure need to be the same unless you're going to do HDR processing. The only thing you need to keep in mind after that is your camera's angle.

Good luck and clear skies!

Hi there

Just wondered if I took s bunch of 30 seconds exposures of the pleades sorry about spelling,.. and then another day took some more on same target..... could you put both of them together and stack them?

[Mirrorgirl]

Hi there
Where would I find final image autosave ?

[chris_g]

Hi there
Where would I find final image autosave ?

What are you using for stacking and image acquisition?

You can add a signature in your user profile that will add that type of information to every post so you don't have to. Check out my replies for an example.

You'll see two sections at the end, one for session control and another for processing...

[Juno16]

On the left side, click on “Stack checked pictures “. Then click on the Stacking Parameters button. Click on the Output tab. In the Output Location section, you should hopefully see where the autosave file went to.

[Mirrorgirl]

Hi yes finally stacked both I'm now on pixinsight and I have stretched my image...but it is bright yellow...do you no how to keep the details of target and take the horrible yellow away so I have a better image to work with
Thanks
Rhoda

[chris_g]

Hi yes finally stacked both I'm now on pixinsight and I have stretched my image...but it is bright yellow...do you no how to keep the details of target and take the horrible yellow away so I have a better image to work with
Thanks
Rhoda

That sounds like light pollution. If it is light pollution, while I've never used PixInsight I use Photoshop, I believe PixInsight has a process called Dynamic Background Extraction. Do an internet search for more details. And there are others that know oh so much more than I about processing in PixInsight

[SkyHiker]

If you ended up using different groups make sure to mark one light as the reference frame against which all others are stacked. Then you'll get a single Autosave.tif for both groups with everything aligned.

While I never had trouble omitting bias frames with a DSLR, later on I did run into trouble with my ASI2600 if I did not include them. So best to include some.

Just to be sure: Did you use raw subs for stacking, or JPG ? Raw is recommended, I have stacked JPG at times and it also worked but all kinds of corrections are already done. So, stacking raw is strongly recommended.

PixInsight has various methods for gradient removal. I don't know PI myself but from what I hear it has a painful learning curve but it pays off.