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About Tommohawk

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  1. M16 from Astro campsite

    Errrr - maybe something between the two??? See what other folk say!
  2. M16 from Astro campsite

    Yep, I struggle with red and green. It's hard to explain colour vision deficit - its not that I cant see red and green, but if it's in a dark or light shade I cant make it out. Similar if it's a small object, like berries in a tree - I cant see them from a distance where most people can, but then if I get closer the colour suddenly appears. In your image I should be able to see the OIII well enough - I just thought maybe this could be a bit stronger. But maybe its just that I'm not used to seeing this quite so widefield.
  3. M81 & M82 from Astro campsite

    Yes and we were only about 10 meters apart - so I can't really blame the sky!! And maybe I haven't identified it correctly either, though I think I'm OK. Course it might be back to front also! Maybe I'll just spin the wheel next time and hope I get lucky!
  4. Pelican nebula (Feature) IC5070

    Aaah I see - nice job!
  5. M16 from Astro campsite

    Bear in mind my colour vision is pretty ropey, so it may be just me!
  6. M16 from Astro campsite

    Hi Carole - that's another nice image and one I'm hoping to get round to in NB. Maybe the OIII could be lifted a bit?
  7. Pelican nebula (Feature) IC5070

    That's very nice Carole, love the NB colour rendition - but leaves me wondering what procedure the 130PDS had to go through???
  8. M81 & M82 from Astro campsite

    Hi Carole - yes very nice and I agree the IFN does seem to match the reference image - nice job! Also as you say M82 does show some filaments sideways form the central area. But my Ha efforts on M82 don't seem to show this - which is a pity cos that's primarily what I was after! I'll post my efforts later and see what you think. Maybe my sky wasn't as good as yours??!!
  9. Ha filter for M82 cigar galaxy

    Hey guys sorry for the uber slow response - a million things on the go! I think I sorted it using the heart nebula which I did a test image in Ha previously and knew what to expect - but the previous go was with a 300mm lens and it all looks a bit different with 1000mm FL. Just not so obvious somehow. Also when using the 300mm lens I'm at F4, where withe the PDS200 I'm at F5. Anyhow it looks like I swapped the OIII and the Ha - though its almost impossible to tell the Si and the Ha apart by looking at them. Whilst doing this I tried to double check they are the right way round too - and thats really tricky. ZWO advise looking at the reflections but thats not at all easy. TBH the 31mm filters are a right royal pain!! Anyhow, I shot a load of Ha (probably!) 60 subs guided at 300s but TBH the result wasnt great - see below (no calibration files). Theres something there but detail pretty poor. When I've done the image best I can probably in just LRGB I'll post that in a new thread and see what folk have to say about how to incorparate Ha. I've seen a couple of fabulous renditions of M82 and was trying to emulate them - but maybe my skills and/or my kit aren't up to it!
  10. Ha filter for M82 cigar galaxy

    Ok, well when I switch to Ha the filter is definitely green! Either I put the filters in wrong or edited the Ascom set-up wrong - I know I did it in a rush, but Jeez! So the bad news is I wasted an hour of sleep last night doing OIII - but the good news is I should be able to get something in Ha after all. Just got to figure out which is which! If I shot an emission target it would be obvious. But my view to the south is pretty restricted. And my view to the east is non-existent. Anyone know a nice emission neb to the north or northwest?
  11. Hi all. Quick query re Ha filter for M82. I'm currently playing with a second hand Quattro 10s which I recently acquired - I'm just checking I can get it collimated nicely before splashing out on an F4 coma corrector. Its also way over capacity for my HEQ5, though I'm currently using that to test it - I've left off the ADM dual mount and guidescope which makes it just doable unguided. Anyhow I'm using M82 as a test subject - because its relatively near the pole so not too horrendous unguided - with the ASI1600mm doing 30s subs at unity gain. I've actually got a passable result in LRGB, but thought I'd add in some Ha. Pushing my luck here of course, but attempting 120s subs with high gain - so far about half are usable. Trouble is the results are pretty poor in Ha - I'm not seeing the spurty Ha emission at all. It may be that 120s is just too short - in the past I've used 300s - but surprised I'm not seeing anything. Only managed to get 7 subs before had to pack up yesterday but hopefully more tonight/tomorrow. Does anyone happen to have an Ha only M82 they could post as an example please? Or any thoughts on this? One possibility is that when I switched my filters from a 5 posn to an 8 posn wheel recently, I maybe muddled the Ha with either OIII or SII !!! But how do I tell then apart? Any ideas please? Maybe I'll just shoot some using the other filters just to see what happens, but really want to make the mos of this clear sky!
  12. Quattro Mirror cell on 250PDS?

    Ok thanks - and sorry for slow reply! 288mm matches the spec given for the Quattro on TS optics website so thats good. Just measured my Quattro and the OD of the tube seems slightly less - about 284. Anyhow it's likely the 250PDS is the same as the Quattro and probably uses the same cell - but it would be really nice if anyone has one and wouldnt mind measuring it for me please! The ID of the tube or the OD of the cell. Thanks!
  13. Tak Epsilon 130 Quick First Light

    OK well that confirms what i thought - not much too see when unstretched, but obviously its all there! Wish there was more clear sky to allow experimentation with all this! Thanks for taking the time to post those images - very helpful. Well you're off to a good start! Not at all sure about settings for that camera - try and follow the recommended settings though.
  14. Tak Epsilon 130 Quick First Light

    Following on from my earlier comment I'm amazed you get such good results in NB with 0 gain. I'm not questioning your method - far from it -the result speaks for itself. Having recently switched to the ASI1600 myself (from DSLR), I started with LRGB 60s exposures using unity gain just because it seemed a good place to start. But have had such limited clear sky I really haven't had the chance to properly experiment with different gain levels. I then went to NB, and went to high gain with 300s exposures. Results generally OK, but with 60s L I get very bloaty stars and similar with OIII and SII at 300s. You're working at F3.3, where I'm at F4, so not a direct comparison, but now I'm wondering if I should be using lower gain settings. Thing is, even with my existing gain, there isn't much to see on the unstretched subs.
  15. Bit of an odd question this. I have a 250 Quattro, and I'd like to get a second tube with focuser which I plan to convert to a 2 piece tube so I can pack it into a suitcase for airline travel for planetary photography. I cant find the tube diameter for the 250PDS from the published specs - so, does anyone know if the mirror cell from a Quattro 250 would go into a 250PDS tube? I think the Quattro may have a bigger tube diameter to avoid vignetting at the front. The point is I might be able to get a 250PDS with a knackered mirror on the cheap, whereas a cheap Quattro isnt so likely. I could simply split the Quattro tube, but I'd rather use one without baffles. Any ideas? Does anyone have a 250PDS which they could kindly measure the tube diameter?