after processing in Pixinsight imaged saved but processing does not appear to be

[rockwall astro]

I am new to pixinsight but very pleased so far.  I am following a few different tutorials to learn different steps.  Today I processed am image and saved it as a tiff file.  When I went to reopen the file it was as if I did nothing to the original stacked image.  What step could I have missed to make the stretched and processed image not save properly?

thanks for your help, Mike

[dnault42]

Mike,

You have probably used the ScreenTransferFunction (STF) to stretch the image before saving.  This tool does not alter the data, rather it just changes how the image is displayed.  To permanently stretch the data you need to use HistogramTransformation (HT) or CurvesTransformation (CT).

There's a good reason the STF tool exists.  There are many advantages to keeping your data linear (not stretched) for as long as possible.  STF allows you to see the effect of changes even though the data is still linear.

You might look at some basic tutorials to get familiar with the operation of PixInsight.  Warren Keller has some free ones that are part of his very extensive tutorial set.  Harry Page also has some great tutorials.  Sean has a big list of PI tutorials that he updates regularly.

Regards,
David