Gradient Xterminator

[batema (Mark)]

I have a trial version on my 32 Windows system and is as simple as a choice between to settings and then let it do its thing or am I missing something????

Mark

[multiweb (Marc)]

Originally Posted by batema

I have a trial version on my 32 Windows system and is as simple as a choice between to settings and then let it do its thing or am I missing something????

Mark

There a two main settings. How strong you apply the effect and where you apply it. Fine structures or larger scale. Coarse to Fine.

Experiment with all. I usually do multiple passes depending on pictures. Starting with Fine/Weak gives me best results. You can also make selections and mask layers to achieve the right levels.

[peter_4059 (Peter)]

Don't forget to select the object then invert the selection so you have the sky selected before applying

[batema (Mark)]

Thank you. I often hear that this is a valuable tool that people use. I'll search for some tutorials.

[multiweb (Marc)]

Originally Posted by batema

Thank you. I often hear that this is a valuable tool that people use. I'll search for some tutorials.

I use it often when I have bad flats or LP close to the horizon. Definitely one to have in your bag of tricks.

[LewisM]

I found Annie's Actions gradient removal tool much better than Gradient Xterminator.

Or you can do it yourself fine tuning a Dust and Scratches overlaying layer in PS. A recent Sky at Night Astroimaging special magazine showed a couple tricks that work well, and cost nothing

[LewisM]

This image of M8 I used the first of Annie's gradient removal tools to fix. I have SEVERE light pollution (Sippy Downs), and her actions work really well.

The gradient previously was harsh.

[JB80 (Jarrod)]

Seeing as I can never take good flats I really need to invest in one of these programmes.
Xterminator is the one always mentioned but I had forgot about Annies Actions.
AA seems to offer so many more process' too but I don't think there is a free trial.

[batema (Mark)]

Do you apply the gradient xterminator tool on the tiff image that has been stacked straight away and then start your processing or process first to the point you are happy with and then apply it? That question is for DSLR images and also I use a QHY9mono so would be taking LRGB images. Would you use it on each RGB or on the combined?????

Mark

[peter_4059 (Peter)]

try this...

http://www.rc-astro.com/resources/Gr.../tutorial.html

[batema (Mark)]

Thanks Peter. I have looked at these and read but I still do not know when to apply the filter?

[peter_4059 (Peter)]

I stretch first otherwise you can't see the extent of the object you are trying to preserve. I normally apply to the combined RGB image - not individual channels because I'm lazy. It would probably be better to apply to the individual channels before combining as the gradient will probably change during the imaging session based on the moving location of the object relative to possible stationary source of the gradient.

[batema (Mark)]

Thanks Peter. I thought as much after my last post. Now for the clouds to go away.

[Exfso (Peter)]

Hey Jarrod, pity you don't live in Australia, I could set you up with a light box, and that will fix your flats problem