How To Reduce Star Sizes In Affinity Photo | Affinity Processing Guide

how's it going everybody's roseanne here for astrophotography and in today's video i'm going to show you how you can reduce star sizes using affinity photo so why would you reduce star sizes um stars are point sources of light across an image and to me they can sometimes detract from the deep sky object that we've worked so hard to take a photo of and so in this case with the flaming star nebula it's a hydrogen alpha image and the scattering of scar stars across the frame kind of hides the nebula in my opinion so we'd use star reduction to kind of make the stars take backstage a bit so the dso can take center stage and pop a lot more i'm going to show you two examples of star reduction one with a lot of stars in the frame like this one and the other one on the galaxy where there's less stars but you'll be able to see the overall effect still in action so i would do the star reduction about 60 through my workflow once i've done my edits to the dso and the edits to the background layer individually i'm kind of proceeding on from there going into like final sharpening noise reduction um and color vibrance etc that's before although i'll do my style reduction if you want to know how to edit astrophotography images in affinity i have a full workflow up there and in the description down below enough talking let's get on with it so the flaming style nibbler hydrogen alpha the star reduction base layer is the stamped merged visible layer like i mentioned after all those edits have been done i would merge a visible layer and star reduction base would be the result of that star reduction is just a duplicated layer so we've just gone right click and duplicate the reason for using the two layer approaches for blending purposes if i want to make if the finished result is too much you can blend it in so what we're going to do there's two ways of selecting the stars i'm going to go to select and you can go the tonal range and highlights and there's no tolerance slider here i have said to affinity can you add a tolerance slider because sometimes it affects the nebula itself that's one way of doing it i'm just going to use ctrl d or select and deselect that the other way is select sampled colors and change the model to intensity and then sample a star basically i'm going to sample this bright one here and then this is going to select all the other stars around it and if you want to select more stars then raise the tolerance higher and higher and higher and if you want to select less then raise the tolerance down lower the tolerance for me i think about 30 is fine doesn't seem to have selected any of the nebula a little bit there but this is fine i want to grow and feather this selection now i want to grow because i need to get a bit of the background sky in this selection as well for the feathering purposes and then feathering just takes that really hard edge off of it so i'm going to go to select and grow make sure circle is picked and i'm going to group only by about two so we can see now we've got a bit of the background sky in our selections it has increased the selection of the nebula but i'm not too worried about that you'll see why in a moment i'm gonna go to select again and then feather feathering takes that really hard edge off of things i always explain it as it's a gentle slope going into a lake bed rather than a sheer drop off of a cliff face so it's just a nice gentle transition i'm probably gonna feather this by about three you'll get a feel of it i can't really explain how much to feather by it depends on image scale and how much you're selected it's more of an experience thing and when you learn and get more familiar with your camera and your telescope combination but feathering is an integral part if you miss out feathering you can have a very solid transition and it's probably not the effect you're going for i say probably because i don't know the effect you're going for my teaching style is very much teaching you the principles and the tools of what i do so that way you can apply it to your own images so i'm not teaching you how to make this picture i'm teaching you the tools with this selection in place there's another two ways you can go about this now you can go straight to the minimizing section with the selection active or you can mask this layer now this one i'm going to actually mask this layer so with all these stars selected with the star reduction layer on i'm going to click mask layer i'm going to use ctrl d to deselect all this or you could have gone to select and then deselect now if i press alt and click the mask we can see the mask we're working with and this is one reason why i wasn't too fussed about the nebula that had been selected there's not much and if really we want to we can take a black brush in here and mask that back out i'm going to make sure i click the thumbnail again of the entire image and then i'm going to go to filters blur and then i'm just going to zoom in a bit and i'll go to filters blur and then minimum blur so minimum blur is the actual star reduction tool that i use i'm going to bring the mirrored side by side view up and then i'm just going to scroll across the image and make sure that i'm happy with the amount that's going on so one 0.5 that's a bit too much so i'm just going to get about 1.2 or maybe even 0.8 1.2 again the amount you uh reduce the stars by it's a matter of personal preference and that's that now i can fully admit that this might be a bit extreme for a lot of people but this is why we've done the two layer approach because if i switch this off that's before that's after i can just go up to the opacity level and change it to about 66 and then begin blending this the higher the opacity the smaller your stars are going to be so i actually want that about 66 i think for me [Music] and i'm happy with that overall effect [Music] now here's one uh fact that the masking comes in handy with look at alfa auriga the very bright star of the flaming star nebula it is the flaming star so it's kind of been dimmed down in in the star reduction process if i click the mask thumbnail here i take my paint brush go to color make sure black is selected i can just use a black paint brush on the flaming star there and that removes it from the mask so it's not been affected on the star reduction layer so now you can see that alpha or ige there in the middle hasn't been selected because it's been masked out you could do the same with these this w of stars for example in this specific example or if there's like a star cluster in your image and you didn't want to reduce the star cluster you could paint out and mask the star cluster so that's doing the star reduction with an image with a lot of stars in it like this one and you can see i think you can easily see the visual impact that reducing the star sizes has had it's really made the dso pop out and the flaming star nebula has really taken front and center stage let's go to the second example now which is the leo triplet so there's a lot less stars in this example less covering the galaxies themselves so this one won't have as much a visual impact as the flaming star nebula but it still is a nice little subtle change to this image star reduction base i'm going to right click that i'm going to duplicate it and i'll call this one star reduction and then from there i'm just going to go to select internal range highlights and again because there's no tolerance slider at the minute it's kind of selected the cores of these galaxies so i'm just going to take the free lasso the freehand selection tool if that's not available right click it and then select freehand selection holding alt or you could click subtract i'm going to hold alt and i'm just going to draw around the core of these galaxies to remove them from this selection because i don't want to reduce these cores a bit here on the hamburger galaxy excellent now i'm going to go to select again and i'm going to grow this selection by about two probably is fine make sure circular is selected no about about three then that's great and then i feather the selection again there are three and i'm not going to bother with masking this layer this time i mask when i feel like a big part of the image is going to be affected and i'm a bit unsure and i want that bit more control it doesn't hurt to mask but in this example i'm just showing you what happens when you don't so with that selection still active i'm going to go to filters blur and minimum blur bring the side by side up so we can see the difference that's going on and then i'll go to select and deselect to get rid of those marching ants and now we can just scroll across the screen here and have a look at what difference is doing it's affected mainly the smaller stars but it's had an overall effect so if we go to 1.5 2 two is very extreme 0.5 not a lot i think 1.2 works nicely for this image the nice thing about this one it's more of a visual thing you can keep changing the threshold and the tolerance there until you get something you're happy with and again it's a subtle effect it's lowered the overall brightness of the image and again if you don't like this you can change the opacity to say 50 and that's even more subtle but it's just a nice amount i think for me 60 works nicely for the leo triplet and i'm happy with that and there you go that's reducing stars the same way in two different images to give you two different visual results using masks as well is not using masks feathering selection expanding selections and the actual minimum tool itself and as why you would do it and how to do it so i hope that you've understood the principles of reducing stars in affinity photo and if you haven't let me know down below and i'll try to clear it up for you also if you have any other requests for tutorials drop them down below in the meantime thanks very much for watching if you've enjoyed this video give it a thumbs up and if you think it could have been better give it a thumbs down thanks very much for watching hope you have clear skies keep looking up keeping cameras clicking i'll see you later

Channel: AstroFarsography

Views: 3,254

Keywords: Astronomy, Astrophotography, Space, Space Photography, AstroFarsography

Id: tjNCzeh2J5k

Length: 11min 55sec (715 seconds)

Published: Tue Feb 02 2021