Author Topic: HDRComposition problem  (Read 683 times)

Nigel Ball

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HDRComposition problem
« on: 2011 February 02 16:56:29 »
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
Nigel Ball
Nantwich, Cheshire, United Kingdom

Takahashi FSQ-106 at f/8, f/5 and f/3.6 on AP900, Nikon 28 mm and 180mm f/2.8
SBIG STL-11000M, Astrodon LRGB, 5nm Ha
ST-10XME, Astrodon HaLRGB
www.nigelaball.com

vicent_peris

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Re: HDRComposition problem
« Reply #1 on: 2011 February 02 18:12:24 »
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.

Nigel Ball

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Re: HDRComposition problem
« Reply #2 on: 2011 February 02 19:30:52 »
Nigel Ball
Nantwich, Cheshire, United Kingdom

Takahashi FSQ-106 at f/8, f/5 and f/3.6 on AP900, Nikon 28 mm and 180mm f/2.8
SBIG STL-11000M, Astrodon LRGB, 5nm Ha
ST-10XME, Astrodon HaLRGB
www.nigelaball.com

vicent_peris

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Re: HDRComposition problem
« Reply #3 on: 2011 February 02 20:24:30 »
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.

Nigel Ball

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Re: HDRComposition problem
« Reply #4 on: 2011 February 02 23:12:44 »
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
Nigel Ball
Nantwich, Cheshire, United Kingdom

Takahashi FSQ-106 at f/8, f/5 and f/3.6 on AP900, Nikon 28 mm and 180mm f/2.8
SBIG STL-11000M, Astrodon LRGB, 5nm Ha
ST-10XME, Astrodon HaLRGB
www.nigelaball.com

vicent_peris

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Re: HDRComposition problem
« Reply #5 on: 2011 February 02 23:41:17 »
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.