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PixInsight => General => Off-topic => Topic started by: Nigel Ball on 2011 February 02 08:56:29

Title: HDRComposition problem
Post by: Nigel Ball on 2011 February 02 08:56:29

Hi all

Following Rogelio's tutorial I've been playing with my wn data on IC434/M42

I am using 300s and 15s exposures

When I use HDRComposition the central core fo M42 is still burnt out.

I've located the problem to the mask generated. It is not masking the core at all. Which parameters do I tweak to fix this?

Thanks

Nigel

Title: Re: HDRComposition problem
Post by: vicent_peris on 2011 February 02 10:12:24

Hi Nigel,

Could you post a JPEG image of both exposures in a linear atare? That's simply open them a save them without making any change.


Regards,
V.

Title: Re: HDRComposition problem
Post by: Nigel Ball on 2011 February 02 11:30:52

Vicent

The jpg are at

www.nigelaball.com/Images/IC434_M42_L_15s.jpg (http://www.nigelaball.com/Images/IC434_M42_L_15s.jpg)
www.nigelaball.com/Images/IC434_M42_L_300s.jpg (http://www.nigelaball.com/Images/IC434_M42_L_300s.jpg)

Thanks

Nigel

Title: Re: HDRComposition problem
Post by: vicent_peris on 2011 February 02 12:24:30

Hi Nigel,

I'm looking your images from my mobile phone, so I cannot inspect them in PI. But I'm pretty sure your saturated areas in the longer exp image haven't a value of 1. Please look which is the saturation value in this image and put a value of about 80% of that for the limit in which HDRC puts over the shorter exp image.


V.

Title: Re: HDRComposition problem
Post by: Nigel Ball on 2011 February 02 15:12:44

Vicent

Thanks

Indeed the saturated value was only 0.7 so I set HDRC to 0.56

I can now see the Trapezium  ;D

Nigel

Title: Re: HDRComposition problem
Post by: vicent_peris on 2011 February 02 15:41:17

Great, Nigel!

What's the more important to understand from this little problem is that it is necessary to always visually inspect the images. It's the only way to learn to think through your eyes. This will make your processing experience more funny, of course. :)

Good luck,
Vicent.