new user! and informations!

Hi Giuliano,

Happy 2018 and welcome to the forum 😉 !

Let me explain about the tools:

- the proper order to use the tools is from top to bottom in Tab 9)

- Background calibration and Background neutralization are 2 different things. Background neutralization will look similar to background calibration but is based on histogram data and will therefore surpress faint nebulosity. So always use background calibration and select pieces of the sky background clear of nebulosity.

- Use the background calibration tool on data that is flat, so this usually means after proper correction with the "remove light pollution" tool.

- The "remove light pollution" and "background calibration" tool, will always perform a background neutralization on your data when you start the tool. The reason is simple, this will help you in getting a good correction/calirbation, if the data isn't neutralized to start with, it will be much harder for you to place the area select boxes correctly.

- The "background calibration" tool will actually make your sky background gray, the remove-light pollution tool won't. It will only correct the gradients in your blue integration. Since the tool works by showing you background neutralized data to start with, you must realize that this neutralization isn't applied to your data when the light pollution is corrected. The correct way to get a gray background is to use the "background calibration" tool after the remove light pollution tool.

- Your blue itnegration must be the result of disabling "neutralize background" in 5) Normalize. This is no problem though, since you can correct this with the background calibration tool.

- The selective color tool will be soon upgraded and better integrated in the user interface.

- Noise removal function will soon come.

Let me know if this eplains APP behaviour 😉 and if you have more questions.

Kind regards,

Mabula

Mabula, When you said to use the tools in tab9 from top to bottom do you mean to say that these tools are performed on the individual channels before the RGB combine? Also, from the above I assume that we leave  "neutralize background" in 5) Normalize as ticked but make sure we also use also background calibration in the correct order in tab9.

Top to bottom. vignetting tab only if you did not use Flats. Then in order do light pollution, background calibration, and start color calibration if you want to use it in that order

Posted by: Tim

Mabula, When you said to use the tools in tab9 from top to bottom do you mean to say that these tools are performed on the individual channels before the RGB combine? Also, from the above I assume that we leave  "neutralize background" in 5) Normalize as ticked but make sure we also use also background calibration in the correct order in tab9.

Hi Tim,

If you need to use the RGB combine tool to make a composite of different channels. Then things will be a bit different.

I would recommend to

• first correct each channel for light pollution and/or gradients with the "remove light pollution" tool.
• Then load the channels into the RGB combine tool and make your initial composite
• After that, you can proceed with background calibration and star color calibration. These last 2 tools only apply for multi-channel / color data.

Using "neutralize background" in 5) is a bit trivial to be honest. I use it myself all the time since it's easy and will give you a quick and better look at your data, but background neutralization should never be the final step in creating a grey sky background. Background neutralization is a simple histogram based way of neutralizing the overall colors in your data, but if you have weak nebulosity in your data, chances are big, this will be surpressed due to the background neutralization. Only proper background calibration will unsurpress it.

So just make sure, that background calibration is done to get a good grey background without surpressing nebulosity of any kind.

Cheers,

Mabula

Posted by: gdwats@comcast.net

Top to bottom. vignetting tab only if you did not use Flats. Then in order do light pollution, background calibration, and start color calibration if you want to use it in that order

Thanks Greg 😉