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Tommohawk

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About Tommohawk

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  1. Thanks for that Carole - I'll check out the plug in.
  2. Hi David/Carole and thanks for the comments and reworked version. None of the data was binned, and the SHO was used as RGB with no blending or luminance. When I said I used the Ha like Lum, what I meant was I relied on the Ha for the detail, but I didn't actually use a Lum layer As you say, the OIII and SII channels (Red and Blue) do look pretty horrible but that's the result of stretching them to blazes. Interesting David that you use unity gain for NB. I've found even with high gain its difficult to get any detail in the SII and OIII and so have been reluctant to try unity gain - I don't want to waste time experimenting with the limited clear sky we have! That said, I recently did the horsehead as Ha(HaR)GB and accidentally left the gain at unity for one session of the Ha and that worked pretty well - it was possible to just stretch it a little more. I'm not sure why I didn't try using the Ha as Lum -it does seem an obvious way to go, and having tried that it's much better certainly from the noise point of view, and it also helps keep the star sizes down. TBH I think I spent so long (I mean several sessions at the PC) trying to force the raw OIII and SII data without bloating the stars that I got a bit fed up with it! I'm sure I read somewhere that using Ha as Lum was a bit naff - as it rigs the data. Maybe I'm muddling this with using the Ha as red. I thought Olly P said he wasn't much on using Ha as Lum? Maybe I remembered wrong. Re gradients - first, Carole you said you used PS to get rid of gradients? Is that a feature I haven't seen or a plug in or something? Oh... I think I misread it - is gradient exterminator a separate app? Part of PI? Also, I'm not sure I understand why folk get so exercised about gradients! If the gradient is an artifact, say caused by a light leak in the filter, then I guess you'd want to correct it - fair enough. But if the gradient is due to a genuine variation in colour across the image, why would you want to remove it? For that matter, even if the gradient is due to LP, if that's the way it really is, that's OK... isn't it? Maybe I'm missing something! Thanks for the tips - I'll have a redo and post again. I've done a quick redo with Ha as Lum and blurred the RGB but now the stars have blue haloes because the blurred B has increased the star size. Might take a while!
  3. Hi! One problem I have when processing is that my colour vision isn't good - red green deficient - so I really struggle to balance things. I use the sample tool a lot to make sure things are about right, but usually I run the end result past my wife who then tells me where I've got it wrong! Your version looks better -she tells me! Actually I can see the difference once its pointed out. I think there are a couple of things causing problems. The Ha is overwhelming, so in SHO there's loads of green. To keep the balance I rack up the S and O but then the balance goes. To make things worse, the star sizes are smaller in Ha, so the bloaty B and R give a magenta-ish halo. I don't have PI, but in PS I tweaked the G curves to push the dark and light shades more, rather than just the mids, and this has improved things. I need to find a way of processing O and S whilst keeping the star sizes small - this would help no end I think. Maybe I just work in Ha/Mono!! Thanks for the input.
  4. Hi all. I did this some weeks ago now - usually I post all the hilarious details of my various screw-ups on the night (leaving the Bahtinov mask on etc) but TBH I cant remember what I did yesterday never mind 4 weeks back, so just the basics for this one. Am now using a TS Optics 72mm with 0.79 reducer instead of my trusty 300mm Tamron F2.8 and all looks pretty good though I don't think I have the spacing right just yet for the reducer. Main issue with this was trying to get detail in the SII and OIII. In the end I just opted for keeping maximum detail in the Ha, and mullered the SII and OIII to breaking point - so a bit like using the Ha as you would a Lum, and using the S and O as you would the RGB. If that makes sense. It was a nightmare trying to control the colour. In the past I've used the Ha flats for all SHO but because the O was so wayward I did separate flats this time. Its helped, but there's a lot of blue toward the top. Similarly a lot of red to the right - but I've fiddled with this for way too long, and that's partly why it's taken so long to post. So - TS Optics 72mm F6 with 0.79 reducer, ASI1600MM Cool, 32 x SII, 26 x Ha, 36 x OIII all 300 sec, high gain (300) DSS PS Hope you like it - as ever criticism or tips welcome, thanks!
  5. As per the edited heading, the OIII and SII have sold, the Ha is still available, £60 inc P and P to mainland UK
  6. Hi. the 31mm ZWO filters are unmounted - they are just plain circular discs. They are typically held in the filter wheel with 3 small screws - see the pictures below. The first shows a filter and how to tell which way round it is - its the only pic I could find. Mine are still in the wheel. The second shows the ZWO filter wheel (on the left) which will accept them. Not sure about other brands of filter wheels. Hope that helps!
  7. Have had interest in the OIII and SII filters, but don't want to split. Anyone interested in the Ha only?? For £60? If so I will split.
  8. Right - finished with the processing at last! Result and write up here - thanks!
  9. This has probably been done a million times before, but it's my first proper go at the horsehead and I've just noticed I can enter it in the imaging challenge section - first time I've had the chance! So - I've used only newts and camera lenses until now and finally at Xmas treated myself to a new TS optics scope (72mm F6 and a 0.79 reducer) During the beautiful weather last week I grabbed some Ha R G and B over a few nights, and got a fair result - I think! Processing a bit weird - main issue was massive Ha haloes round Altinak, which I sort of solved by blending in the relatively good Lum date around Altinak over the Ha data. Has left some blue halos because the blue was also pretty burned out, but I didn't want to manipulate things too much. Not sure I have the reducer spacing quite right - some less than round stars in the corners so will need to experiment a bit there, but general pleased with the new gear. Certainly way easier to focus than the camera lens! I used the Ha as the Lum, (95% opacity) because the Lum was surprisingly weak, and blended 20% Ha in with the Red channel. This seems to work quite well I think - the red isn't quite as saturated as some of the examples I've seen, but if I strengthen the red near the horsehead then the background red becomes way too much across the rest of the image. Probably other ways of working it. I did try blending some Lum with the Ha, but that didn't really help, and I tried blending a smaller amount of Ha with the G and B channels, which some folk seems to have done, but that didn't help either. I would call this Ha,HaR,G,B because the R has Ha blended in - but not sure if that's correct terminology! So, TS72 F6 with TS 0.79 reducer, ASI1600 cool @-15 degC with ZWO NB filters, 27 x 300s Ha (gain 300), 14 x 300s Ha (139 gain), 60 x 60s R (139gain) 32 x 60 G (139 gain), 28 x 60s B (139 gain) and L data only used for halo masking. SharpCap, DSS, PS. Hope you like it!
  10. In good condition with original packaging - relatively little use. I've attached 2 pictures which I've taken with these filters. Note that these are the early version narrowband filters, still available from First Light Optics for £296 (Originally £396) They are 31mm unmounted and require the appropriate filter wheel for use (ie they are not 25mm screw in type) rfrf Selling price includes insured delivery within 1-2 days. NOTE: free delivery but to UK only! These are also advertised elsewhere so may be withdrawn. FURTHER REDUCTION to £160
  11. Hi Roland and thanks for your thoughts and the links - hope to check them out but busy grabbing as much data as I can whilst the skies are clear. I'll experiment with data and will post my efforts here for sure. Probably gonna take a while though cos lots else on the go and also the boring issue of work!
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