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Xiga

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About Xiga

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    Star Forming

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    https://www.flickr.com/photos/32169902@N00/albums/72157674925075376

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    Northern Ireland
  1. Cheers Paul. APP is short for Astro pixel Processor. It already has some post-processing capabilities at the moment (with a lot more to come) but right now it's main USP's are in pre-processing (especially if you do Narrowband with a DSLR) and also mosaics, people are saying it handles mosaics better than anything else out there. I don't do mosaics myself, but I can certainly vouch for the DSLR Narrowband algorithms it uses.
  2. Decided i really wasn't happy with the colours in the last version. On second viewing i thought it actually looked a bit garish (why didn't anyone tell me, lol). So i went back and tweaked the colours. It's still garish mind, just in a slightly different way now
  3. IC1396

    Hi Mike It does refer to LRGB processing. So just as normal, you start out by processing your Lum and Colour (RGB) images separately. In Photoshop (which is my tool of choice) i open the Colour image and convert it to Lab Color Mode, then i copy the Lum image into the Lightness channel, before converting back to RGB mode. (i then close the original Lum image). I then duplicate the layer and set the blend mode of the top layer to Luminosity (i think this forces the bottom layer to then act just as a colour layer, but you can set it to blend mode Color just to be safe). The Colour layer will inevitably have some colour noise in it (some more than others, but there will always be some there), and one of the best ways to eliminate it is to simply apply a small Gaussian Blur to the whole Colour layer (usually a few pixels is enough, but it can vary). When you see the before and after effect it's just awesome, it completely cleans up all the colour noise, and because all of the actual detail in the image is contained within the Luminosity layer you don't lose any sharpness or detail. An added bonus is, if you don't own a high-end APO scope and a lot of your stars have coloured artefacts around them (i often get this) it also cleans most of them up too. So it's all good :-) An alternative method is simply to use Filter-Camera Raw and crank up the Color Noise slider. I think PS also only applies this to the Color element of the image and not the Luminosity. I've used it quite a bit, and really like it. Either method is fine, so give both a go.
  4. IC1396

    WOW indeed, that is absolutely gorgeous! I really like what you've done with the colours here. Fantastic image! ps - You clearly know what you're doing, but if I may add a very small comment, at 100% zoom the orange areas are showing a minor bit of colour noise (red speckling). A small blur of the colour layer will clean that right up. :-)
  5. Good point Craney! I knew there was a reason i specifically framed it that way
  6. IC1396 with DSLR

    Hi Adam I agree with all of the above. This is a lovely image. The elephant trunk is showing nice and clearly, which for a Non-Narrowband image is quite the achievement. We're from the same neck of the woods (N. Ireland) and i too was out on the same night as yourself. For me, at least, between the nice patches of clear skies there were unfortunately quite a few small, but regular, patches of fast-moving clouds about. I was shooting 20 mins subs of the North American Nebula, and i lost a good few subs due to clouds, and even of the 5 that i've deemed to be keepers, i'm pretty sure 2 or 3 were also affected somewhat too. So i think conditions were definitely against us on this occasion. Just a thought, but, i would try shooting this with your Astronomik Ha filter. This is an Ha-rich target so it will really bring out the contrast. Then you can use the Ha as your Lum data and add the data from above as your RGB data. That should give a full colour image with a lot of nice contrast.
  7. IC5070 - Pelican Nebula - H-alpha DSLR

    Hi Adam Glad you like the star reduction technique! I can't take credit for it though, i picked it up from the great Olly Penrice himself on this very forum a while back. Something like this is always down to personal taste (so please take this with a pinch of salt), but if it was me i would go for a bit 'less is more' for the image above. The pixel size for the Minimum filter can be totally dependant on the image, i've used as high as 1 pixel before, but more recently i had to use 0.3 pixels for a pleasing result, so i would experiment with a lower pixel size (or just a much lower opacity for the layer) and see if you prefer the result. Remember, the object is not to remove the faint stars but just to reduce down the bigger, brighter ones. Ciarán.
  8. Thanks for all the kind comments guys Sean, you're quite right. This being my first 'full' NB image (i.e Ha with OIII, can't see me ever bothering with SII) I do indeed feel a special bond with it, lol. ps - What do people think about the framing? I keep going back and forth over the one above and the one below, but every time I think I prefer one over the other I change my mind!
  9. Finally managed to add some proper Ha to the previous version (which was a noisy mess of a thing!), so this is now: 7 x 600s and 14 x 900s (4 hrs 40 mins) of Ha 17 x 900s (4 hrs 15 mins) of OIII SII synthesized using a blend of 60% of Ha and 40% of OIII Nikon D5300a 2" Baader filters Skywatcher 80ED Skywatcher HEQ5 Pro 50 Bias and 30 Flats Guided with PHD2 and a finder-guider (QHY5) Captured with SGP Pre-processed in APP Post-processed in PS The extra Ha data has made a massive difference. So this one was much easier to process. Still not completely happy with the colours, I may tweak them a bit at a later date. But for now I think I'm pretty much done with this target, time to move on to a new one methinks! C&C welcome as always. Clear skies! https://flic.kr/p/GBb38M
  10. Horsehead Nebula B33 - H-alpha DSLR

    Well, I suppose if I strain myself (!) I can see it too, very very slightly, but then part of it is probably also the brain playing funny games seeing as the nebulosity is travelling in the same direction. If this came from my own gear I wouldn't be losing any sleep over it. I leave that level of nit-picking to those with the Takahashi's et all of this world (and in any case, ignorance is bliss, or at least easier on the wallet!)
  11. Horsehead Nebula B33 - H-alpha DSLR

    I think this looks great. Maybe it's just me, but i'm not seeing too much in the way of artefacts. You must have stayed up late for this one Adam. When i was packing up the other night, Orion was looking absolutely majestic overhead. I'm yet to image Barnard 33 myself, and would have loved to do so at the time, but with work in the morning i figured any less than 4 hrs sleep was probably not going to end well Cracking image.
  12. IC5070 - Pelican Nebula - H-alpha DSLR

    Very good. I use that one a lot too I have to admit (although I sometimes find that it darkens the background too, which I don’t always want). I also use a different method too, although I openly admit it’s a bit more harsh. Saying that, you have control over how much to apply, although I usually end up over-doing it myself! Select Brighter Stars Expand by 4 pixels Smooth By 2 Pixels Filter-Other-Minimum (1 Pixel) Edit-Fade Minimum (to taste, e.g 50%) If all done in a separate layer then you can always use the Opacity to back off a bit too (in case you went too far with the Fade Minimum setting) It can drastically reduce the impact of the stars, if that’s what you want. I sometimes find Carboni’s one doesn’t go far enough for me, but then I often don’t know when to stop! :-P
  13. IC5070 - Pelican Nebula - H-alpha DSLR

    That looks lovely Adam. Really nice detail in there, good job! Do you do any star reduction in your workflow? I always do it near the end, just to make the stars a little less distracting, and it usually makes any nebulosity really stand out more. What program do you use for PP?
  14. Cheers mate! :-) Yes, OIII is doable with a DSLR, but you need looong exposures, and lots of them to boot! Not exactly efficient, but certainly possible. ps - I was out again last night. Managed to grab another 13 * 900s of Ha. I reeeally wanted to go for 1200s, but after initially getting rained on (!) and frantically dis-assembling everything and getting it all back inside, it then cleared up, and being the insane person that I am I went back out again (cue another hr of setup). Didn't want to risk losing any subs to clouds, so decided to compromise at 900s. And wouldn't you know it, the skies were perfect for the next 4 hrs! Will post up the new version when I get a chance to process it later in the week.
  15. NGC7000 - H-alpha DSLR

    Great work Adam ps - You should check out Astro Pixel Processor. It's meant to handle mosaics better than anything else out there (even PixInsight). I've been using it to pre-process my Ha and OIII DSLR subs and I've been very impressed. It has a 30 day trial too, so nothing to lose! :-)
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