Can you create a simple layer to work between 2 exposures?

[swag72]

I haven't used Photoshop for Astrophotography, but do use it for normal daytime photography. The ability to have different layers and be able to adjust the opacity of them so that you can get different strengths showing through would be really useful for astro work.

So, if I create 2 images of the same target using different exposure lengths so that I can better capture the feint outer galaxy arms for example, is there a way to layer that with the shorter exposure then somehow be able to select the bits to show through?

[vicent_peris]

Hi,

You don't need any kind of masking to blend a short exposure with a longer one. For this work you have the HDRComposition tool, which generates one image with the dynamic range of both input images.


Best regards,
Vicent.

[swag72]

Brilliant Vincent, thank you. Will give that a go - Just put both images in and it throws out one combined image with the best of both?

[georg.viehoever]

... Just put both images in and it throws out one combined image with the best of both?

More or less correct, just read http://pixinsight.com/forum/index.php?topic=2320.0
Georg

[Harry page]

Or you could watch a little vid http://www.harrysastroshed.com/HDR%20comp.html

Harry

[swag72]

Cheers both! Didn't realise you'd made a video of this too Harry!!

[Warhen]

Hi guys! Along this track- how would I average a result w/ an original? Let's say the result of a transform's minimal settings is too strong, how can I easily blend it with the before at 50-50, 25-75%?

I am a complete dunce at Pixel Math. Is there a source for some very simple to follow equations for a non math guy? Like you Vicent, a musician but w/o your mind for numbers!

Thank you!

[Mike Reid]

Hi Warren,

See attached screen capture of pixel math.

Mike

[Warhen]

OMG, even I can handle that! Thank you Mike!! Are there some other powerful/common expressions I can add to my bag o' tricks? Do we have these posted anywhere? Michael, thank you for taking the time.

[sleshin]

Hi Warren,

Sometime ago, Juan posted a list of pixel math expressions that reproduce the various "Blend" modes of PS in PixInsight. Here's the link to that list.

http://pixinsight.com/forum/index.php?topic=2409.msg16165#msg16165

HTH

Steve

[Warhen]

Thanks to all of you for being so helpful. I want to publically thank my friend Steve Leshin, a very kind hearted man indeed. He and I did a Skype screen-share session yesterday which helped me tremendously. Thank you Steve and to all the PI community for helping me learn and also document it.

[Mike Reid]

This thread was the spur that got me motivated to go off and write a blending script.  See,
http://pixinsight.com/forum/index.php?topic=3902.0

Mike