Digital Development with mask option?

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puckja
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Digital Development with mask option?

Post by puckja »

Recently I imaged Jellyfish nebula and B33, both has bright stars nearby. Some people suggest masking out bright stars during histogram stretching. Since ST does not literally have stretching tool, I wonder if it is possible to has mask option in the Digital Development Module? And will that option really allow locally controlled stretching?

Thanks a lot for the idea.
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Re: Digital Development with mask option?

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puckja wrote:Recently I imaged Jellyfish nebula and B33, both has bright stars nearby. Some people suggest masking out bright stars during histogram stretching. Since ST does not literally have stretching tool, I wonder if it is possible to has mask option in the Digital Development Module? And will that option really allow locally controlled stretching?

Thanks a lot for the idea.
Hi Puck,

I wouldn't recommend selective stretching like this, but if you r4eally want to, you can achieve this with the Layer module; stretch the image the way you want with the Develop module, then go into the Layer module, click Undo->Bg and create a suitable mask that preserves the stars. Use the Mask Fuzz parameter to make a smooth blend.
Ivo Jager
StarTools creator and astronomy enthusiast
puckja
Posts: 30
Joined: Thu Sep 19, 2013 3:27 pm

Re: Digital Development with mask option?

Post by puckja »

Ivo:

Thanks for the advice. I will try it out and see if I like it.

Another related question: I absolutely love the clean background ST gave me. Often people comments on the "black point" (I guess the minimum of the histogram) has been cut too high so it looks a little bit "cutting too hard". I wonder if ST gave us the control in one of the parameters in the Digital Development?

Thanks again for the help!
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Re: Digital Development with mask option?

Post by admin »

(apologies for the tardy replies - I'm battling a wrist injury at the moment... :cry: )
Often people comments on the "black point" (I guess the minimum of the histogram) has been cut too high so it looks a little bit "cutting too hard". I wonder if ST gave us the control in one of the parameters in the Digital Development?
What you're looking for is the Skyglow parameter in the Develop module.
StarTools should never ever clip your data, but some people that use cheaper screens (e.g. laptops) may not be able to see the full dynamic range (not really your problem perse :) ).
Ivo Jager
StarTools creator and astronomy enthusiast
puckja
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Joined: Thu Sep 19, 2013 3:27 pm

Re: Digital Development with mask option?

Post by puckja »

Thanks for the reply. The ST's support is top notch. I have never seen any online forum support with such excellent diligence. Seriously!

Sorry to hear your wrist injury and be easy on it. We need your smart brain and good hand to keep pushing ST to the new level. :thumbsup:

Skyglow is what I would guess to ease up the black point. I often pushs Digital Development as far as I could and the background already has some "glow" (noise). Then, I raises the Dark Anomaly and reduces the Dark Anomaly Headroom to zero to reduce the background noise a little bit. Will that move be the source of the critics of "cutting too hard"?

(You don't need to reply right away but wait until you are getting better.) :D
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Re: Digital Development with mask option?

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puckja wrote:Thanks for the reply. The ST's support is top notch. I have never seen any online forum support with such excellent diligence. Seriously!

Sorry to hear your wrist injury and be easy on it. We need your smart brain and good hand to keep pushing ST to the new level. :thumbsup:

Skyglow is what I would guess to ease up the black point. I often pushs Digital Development as far as I could and the background already has some "glow" (noise). Then, I raises the Dark Anomaly and reduces the Dark Anomaly Headroom to zero to reduce the background noise a little bit. Will that move be the source of the critics of "cutting too hard"?

(You don't need to reply right away but wait until you are getting better.) :D
Thanks for your understanding Puck - much appreciated! :D
Will that move be the source of the critics of "cutting too hard"?
Yes, that could well be the source of it!
Ivo Jager
StarTools creator and astronomy enthusiast
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