russ.carpenter Posted March 28, 2017 Share Posted March 28, 2017 I'm an astro photographer and frequently use Affinity Photo to fine tune images I've produced in specialized astro imaging programs, such as PixInsight. I have a question that's probably painfully naive, for which I apologize in advance. Astro imaging constantly uses masks, because elements such as background, stars, galaxies and nebula present completely different processing problems. One of the most common types of masks is known as the "luminance" mask. I've attached a typical luminance mask, which was produced from an RGB image, using the "extract CiE L*" command in PixInsight. In this case, the purpose of the mask is to manipulate the brighter parts of the galaxy, while leaving the faint details and background relatively untouched. To work properly, many of these masks need to include a full range of shades of grey. My question is: can this kind of mask be produced and/or used in Affinity Photo? Thanks for helping a newbie. Russ Link to comment Share on other sites More sharing options...
Frank Jonen Posted March 28, 2017 Share Posted March 28, 2017 You could try the following: Duplicate the layer Run a couple of transforms to get the best edges, use Black and White to dial it towards the colours you want the mask to focus on most. Layer > Rasterise to Mask Nest the mask to the original layer. You can go back and repeat till you've found the balance that gives you the best mask. Link to comment Share on other sites More sharing options...
rmar Posted March 29, 2017 Share Posted March 29, 2017 Can you use this method for your astro image? https://www.youtube.com/watch?v=FVtnMuHsFig https://www.youtube.com/watch?v=nKIlckVCCF0 If not, you can make luminosity layers using Silver Efex https://www.youtube.com/watch?v=qDrAn9883Ik&feature=youtu.be&t=329 Skill Level: Beginner, digital photography, digital editing, lighting. Equipment: Consumer grade. Sony Nex5n, Nikon D5100, (16MP sony sensors) Paid Software: Affinity Photo, Affinity Designer, Lightroom4 Free Software: NIK collection, Sony CaptureOne9, Cyberlink PhotoDirector6, Hugin, ImageJ, MS Ice, Davinci Resolve Computer: Win10 home, CPU Skylake I7-6700, GPU Saphire HD7850 1G, Plextor SSD Link to comment Share on other sites More sharing options...
Marimo Posted March 29, 2017 Share Posted March 29, 2017 Hello There is a Action for LMhttps://forum.affinity.serif.com/index.php?/topic/30523-luminosity-masks-for-adjustment-filter-layers/ and https://forum.affinity.serif.com/index.php?/topic/27214-luminosity-masks/ Link to comment Share on other sites More sharing options...
kirkt Posted March 29, 2017 Share Posted March 29, 2017 You could try the following: Duplicate the layer Run a couple of transforms to get the best edges, use Black and White to dial it towards the colours you want the mask to focus on most. Layer > Rasterise to Mask Nest the mask to the original layer. You can go back and repeat till you've found the balance that gives you the best mask. This approach is amenable to working with with 32bit images (curve, B+W, etc. tools are all 32bit compatible) so consider using a 32bit image as source when you apply your edits. Also, when isolating a luminance range, the Curves adjustment layer permits you to specify the input range of the curve, so that the curve affects a specific portion of your unbounded 32bit data. This can be helpful in producing/avoiding clipping in the mask. kirk Link to comment Share on other sites More sharing options...
anon1 Posted March 29, 2017 Share Posted March 29, 2017 You could try the following: Duplicate the layer Run a couple of transforms to get the best edges, use Black and White to dial it towards the colours you want the mask to focus on most. Layer > Rasterise to Mask Nest the mask to the original layer. You can go back and repeat till you've found the balance that gives you the best mask. guess how much better this would be in a node based environment :wub: https://forum.affinity.serif.com/index.php?/topic/15873-coming-2016-32bit-hdr-editing-sneak-preview/?p=81085 Frank Jonen 1 Link to comment Share on other sites More sharing options...
russ.carpenter Posted March 29, 2017 Author Share Posted March 29, 2017 Thanks for all your interesting thoughts. For now, it seems that the most efficient solution is using blend options, although I will need to retrain my brain. I will be glad to have immediate visual feedback on the impact of changes to the blending curve in adjustments and live filters. Russ Link to comment Share on other sites More sharing options...
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