Gradient Extraction

When doing a gradient extraction I generate the dots but most of the time they are too close to the border. I always have to remove them one by one just to make sure the extraction process isn’t confused. So my question is can’t you adjust that so the dots stay away from the border?

If you crop your image to make the edge clean, i.e, without black border, as we recommend, this is not an issue at all.

I don’t crop my images so early in the processing stage because I need to align with narrowband data and separate stars. If I crop I won’t be able to align these 3 stacked images.

Why? Of course you could.

However. If you don’t wanna crop you can put your samples yourself.
Many people think you need a lot of samples in the image, but this is wrong. A few, well placed, that works. Especially with RBF algorithm.

Because if I crop the dimensions change. If I crop 3 images I end up with 3 different sizes. I’m pretty sure Siril will give me an error message during registration that the dimensions are not the same.

No. Siril is able to register images with different size.

Just a few days ago I had 2 different image sizes from the same camera because I used the native driver and the Ascom driver. It is a Risingcam IMX571 and the difference was just a few pixels between the two drivers. I tried to run the OSC_Preprocessing script on those images and it failed to do it. It said ’image dimensions are not the same’.

you cannot calibrate or stack images that have different dimensions, but registration is possible

That makes a lot of sense, thanks.

You can use the command-line version of the crop command to crop each image identically.

So for example, I have a RASA 8” but want to take out the stars and use the stars from a refractor TS Optics CF90. The RASA is 400mm and the CF90 is 432mm. So can I register these 2 images and Siril will do some resizing so both images will line up nicely?