issues with masked stretch

[hectorbdn]

Hello I'm trying to process my M45 I did this last weekend, I'm in the point I have to stretch my image , histogram transformation works fine but I want to use masked stretch , I never had issues before but this time it just looks like it did nothing! I ' d read all the tutorials I've found and all says kind of the same "do a preview with a background , target background 0. something and blah blah, harry astroshed says to write the amount it gives STF , warren keller book says the median in statidistics , lightvortexastronomy an amount between 0.10 and o.20 " well.... i tried everything and all the time it gives me a result it looks like it didn't stretch anything at all! indeed if i do STF It looks like the result i want , a little redish tough .... well I'm kind of stuck here, i really like the masked stretch look... hmmmm might someone tell me what im doing wrong? 

[rdryfoos]

I think you have to use masked stretch in non linear state.  When ever I try it in linear state I get errors that the image is too dark to stretch.

[hectorbdn]

I think I said it wrong, always I mess with the non-linear  linear terms 

[hectorbdn]

I think you have to use masked stretch in non linear state.  When ever I try it in linear state I get errors that the image is too dark to stretch.

do you mean I have to stretch first and later use maskedstretch?

[hectorbdn]

for a better understanding of my issue I will add some pics :

[rdryfoos]

Did you put a mask on the image prior to the use of masked stretch?  You are not supposed to---the tool does it by itself. I say this because the image looks red--like it has a mask.  That may explain why there is little impact.

[hectorbdn]

Did you put a mask on the image prior to the use of masked stretch?  You are not supposed to---the tool does it by itself. I say this because the image looks red--like it has a mask.  That may explain why there is little impact.

thanks for your answer but the image has no mask applied 

[aworonow]

It looks like your brightest stars are pretty well saturated already. I think masked stretch recognizes that and simply says, "My work here is done!" (Kind of like trying to apply the same masked stretch twice...does not work.)

Also, you should take a look at this https://pixinsight.com/forum/index.php?topic=4055.0 and make sure you get the linear work done before going to a stretch...the colors of your images suggest you've not done the background neutralization and color calibrations yet, so stretching is not appropriate at this point.

Alex

[hectorbdn]

It looks like your brightest stars are pretty well saturated already. I think masked stretch recognizes that and simply says, "My work here is done!" (Kind of like trying to apply the same masked stretch twice...does not work.)

Also, you should take a look at this https://pixinsight.com/forum/index.php?topic=4055.0 and make sure you get the linear work done before going to a stretch...the colors of your images suggest you've not done the background neutralization and color calibrations yet, so stretching is not appropriate at this point.

Alex

I didn't do BN because in my experience it eats must of the dust around the object, I.might be wrong but I will try anyways, I guess you are right, I will repair over saturated stars and try once more if it works then good if it don't then I will do BN and color calibration, well thank you very much for your answer I think I can move on on my image


Thanks!