Processing comparison

[ballaratdragons]

I took the hints from people in here and gave 'Deep Sky Stacker' another go.

I have processed a Trifid image from tonight in both Deep Sky stacker and Registax.

The image stacked in Deep Sky Stacker is 8 images and 6 darks,
The image stacked in Registax is the same 8 images with NO darks.

Opinions please. :thumbsup:

1. Deep Sky Stacker
2. Registax

[iceman]

To me the registax one looks better, a little less burnt out and perhaps better aligned.

[ballaratdragons]

I agree Mike.

I haven't done any processing in Photoshop yet on either of them. I just wanted to see the stacking differences.

[ballaratdragons]

Oops, sorry, I did do something. I lifted brightness and contrast a tad on both (equally). Other than that, nothing.

[iceman]

The first one looks too saturated, to me.

[ving]

ditto that...

[ballaratdragons]

They are both pretty bad, but it probably has a lot to do with the Toucam dying a terrible death. Both images are cropped from very badly affected Amp Glow images.
The image capture settings were turned waaayyyy up to get anything at all. It has become almost impossible to image with it.

I just wanted to try a comparison of Stacking results. Bit hard when the detail is screwy.

[little col]

looks like deep sky stacker has not aligned them frames very well and the registax image looks more better stacked:)

[Terry B]

The stars on the deepsky stacker image are very blocks and look like they have been over processed in some way. Have they been summed or averaged when stacked?

[ballaratdragons]

What's 'summed' and 'averaged'? :shrug:

[Terry B]

These are different ways to add images together. The process used is to align the individual frames creating new aligned images and then each frame needs to be added together. This can be as a simple summing of the data or the data can be averaged. There are lots of other methods as well.
Some of the methods are summarised in http://www.astrosurf.com/buil/iris/tutorial2/doc121_us.htm
This is specific to Iris but the principle is the same.
I haven't loooked at "deep sky stacker" but registax uses an averaging process of some type rather than summing the data.

[Marko of Oz]

The object I've put a square around in your Deep Sky Stacker image appears to be missing from your Registax image. What could it be ? :shrug: It isn't because of the slight difference in cropping.

[ballaratdragons]

That's interesting, Mark. Dunno why it vanished. I notice by jumping from one image to the other that many of the stars in the Registax version are dimmer, but that one should still be visible, and it's not :shrug:



Thanks Terry, I better have a read :thumbsup:

[ballaratdragons]

Aggghh, it's all in French! :scared:

[Terry B]

Try
http://www.astrosurf.com/buil/us/iris/iris.htm
Mine is is english or try here (http://www.astrosurf.com/buil/iris/tutorial2/doc11_us.htm)
Use the link on the above page to the tutorials on stacking.
Curiusly when I link from my post it is in english but when I link from the quited link in your post it is in French and a different page.

[Terry B]

As an aside there is a tutorial on the Iris site about removing sky gradients. This might be usefull to help remove your amp glow.

[ballaratdragons]

:thumbsup: more reading :)

[ballaratdragons]

I have just downloaded Iris, and couldn't work out how to do the Gradient removal. I gave it a go and it put crosses all over the image and then it wouldn't go any further.

I then read the tutorial and it says I have to type commands in like we used to with an old Commodore 64!!!!

I think I'll give it all a miss before I chuck this pooter thru the window.

[Terry B]

I am not into command line stuff either but I have found iris to be pretty simple. It has a little command line box that is easy to use.