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James

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Posts posted by James

  1. 55 minutes ago, John said:

    Seeing something for the 1st time is always the big challenge. Once you have done it and know what to look for, you often find you can achieve something similar under slightly less favourable conditions and / or with a smaller aperture.

    That's a good point..

    I've been lucky enough to visit La Palma twice in the last ten years or so, generally with a DSLR for time lapsing rather than a scope though I did get a twirl with an Evolution 8 for a couple of nights. The primary difference telescope-wise was objects generally appearing much brighter and therefore often more detailed - and up near the observatories the seeing was usually excellent so planetary viewing was much improved. I figured the view was really only limited by the aperture and optics at that point. Oh, and my then 46 year old eyes..

    The main difference that I found was zodiacal light being much brighter than the Milky Way from home, much less twinkling of stars and the Milky Way itself was ridiculously bright and detailed - I could see it from inside the kitchen where we were staying with a dim 40watt light bulb on above me. One particular night there was no twinkling pretty much down to the last few degrees near the horizon and I was able to walk around and follow paths without needing a torch (I was careful!). I guess proper dark skies allow for proper dark adaption, sort of a virtuous cycle... I'm pretty sure the Milky Way and Jupiter were casting a shadow that particular night. I took my son, then 11, up to the top with me and the things he described like the number of stars visible in the Pleiades was pretty mind boggling.

    Of course, that meant even though I could see all that extra stuff he could see more... 🙄

    So, in answer to the OP... actually there was nothing I could see that I couldn't see at home (well, except the Zodiacal light - have to go to Kielder for that) but everything was way brighter, clearer and more detailed. 

    James

     

    • Like 3
    • Thanks 1
  2. On 19/12/2023 at 21:45, MartinB said:

    On my calibrated monitor there is a hint of green.  You should try to see if you can find Edwin Hubbles Cepheid variable in there.

    There is a tint isn't there. Its not on my calibrated laptop, but is on my oh so nearly calibrated desktop... will tweak that after Christmas probably... Hmmm... I'll have a look for Hubbles Cepheid variable.. but only after I've gotten used to my new glasses prescription :)

    Cheers, James

  3. 10 hours ago, Paul M said:

    No! Don't overcook it!

    That's M31 as it was intended to be seen. Sometimes an image is presented for science, sometimes for awesomeness of the subject. Here we have the latter :)

     

    Thank you :)

    I know what you mean about overcooking... that said.. I didn't get as much of the blue stuff come through at each end and I suspect I was over heavy with a mask... if I go back and correct that I may as well add just a smidgeon of Ha... but then I'll over do it.. oh I don't know!!

    James

    • Haha 1
  4. For me Andromeda is getting out of easy imaging territory (very dark to the east but Exeter is to the west so I don't do LRGB imaging for objects that way) so I'm calling a halt to my efforts for a while... I've done M31 as LRGB - I have some Ha but couldn't face doing it again with Ha in yet, maybe after Christmas, should make it pop so to speak :)

    All 2 minute subs:  28x L, 16x Red, 21x Green, 22 Blue so just 6 minutes shy of 2 hours. Taken with a WO Cat 71, ASI2600mm-Pro, iOptron CEM40 Mount controlled by an ASIAir, processed in PixInsight.

    I'm not sure what the 'correct' way to display Andromeda is, this way up looked best to me :) Clicking on the image probably gives a slightly clearer version...

    I've been tempted to see if I could capture the patch of OIII that's allegedly there and see if any Ha turns up but I think I'll need more Ha for starters as none, or very little is showing on my Ha data outside the galaxy itself..

    James

     

     

    M31_no_ha_DS.jpg

    • Like 28
  5. Still catching up on the sleep after a star party with three clear nights (perhaps mercifully Thursday was cloudy so got some sleep after a very clear Wednesday night) -  but those up for just Friday and Saturday nights got a treat too.. I really don't want to know if it stayed clear after I left on the Sunday 🤫 Unusually, I left with a largely dry tent!!

    Did a bit of time lapsing, some standalone shots (some attached), some visual through Lynn and Kevs' scope, struggled with the faint fuzzies somewhat but we were looking at some very obscure NGC's. Also popped out with Nick for some photos of nearby tree, found by @davew previously  - the exact location will remain slightly secret in case the Sycamore Gap tree killers are still at large.. As it happens we ended up comparing what a new iPhone 15 can do versus a DSLR and, subject to the phone being in the hands of a very competent user and my DSLR being in the hands of a moderately competent user it's pretty clear that the phone was holding it's own. I'm guessing I can print up to and beyond A3 though with the DSLR's output.. so I'm chalking that as a win... ;)

    Much like I hear from the red field at Kelling (running the same weekend) we did have an unfortunate incursion by a young lady with headlights/foglights on full one night - once the blind/dark spots had faded it was back to business. The skies at Kielder are very very dark - there's always been some light pollution from Newcastle way, considerably hidden by a hill/bank of trees but there's a gradual increase from light pollution from the north too. It's still great being at a dark site where the only indication there's cloud overhead is that some stars are hidden..

    Some random images attached here - I suspect the images are clearer/sharper when clicked on.. :)

    James

     

    tree2.jpg

    redlight.jpg

    tent.jpg

    topfield.jpg

    topfield2.jpg

    lasvegas.jpg

    • Like 16
  6. Whilst it's unlikely to be this I have seen similar spikes when I've had a small patch of dew on my objective. Last time was with M45 as well back in December. Was using a refractor, had no spikes on anything else bar the lower part of the image. Never did figure it out but ramping the dew strap up to 100% made it go away so I figured it was that...

    James

    Edit:  " ramping the dew strap up to 100% made it go away "  I guess if my optics were pinched due to cold it might get resolved with a bit more heat but I've imaged on many colder nights more recently and not seen this..

    • Like 1
  7. 3 minutes ago, Zummerzet_Leveller said:

    Thanks James.  I too had some annoying gradients.  Just integration time to get the data and the pretty good gradient tool in Siril.  Isn't 10hrs with a OSC equivalent to 2hrs with a Mono... 😉

    image.thumb.png.c1d1acc4e7d59601bc5b40596d5e9c8e.png

    Hmmm… not sure about that 😊 maybe I’ll have another look at my data :)

    • Haha 1
  8. That’s lovely and there is a ton of dust in that area. I just finished the same target but with the RedCat 71 and the mono version of the 2600; when it came to colour calibration in PixInsight I needed a bit of background that wasn’t dusty… I struggled!

    • Thanks 1
  9. With recent clear skies I think I'm finished this one now, in previous years I've only been able to collect Ha, this year I've managed to get some OIII and SII too so here's my version of the Rosette Nebula. There's an absolute ton of Ha around it and if only we got some more clear skies I'd try to mosaic between the Rosette to the Christmas Tree Nebula area. But.. we don't so that'll probably not be happening!

    This image is taken through a William Optics RedCat 71 with an ASI2600MM-Pro using Optolong 3nm narrowband filters on an iOptron CEM40 all managed with an ASIAir, processed in Pixinsight with a little help from Blur/NoiseXterminator..

    All subs are 5 minutes with 29x Ha, 20x OIII and 19x SII so just over 5 and a half hours data. The weakest data is the OIII, note to self... in future make the effort to get more OIII!. Of the three filters the OIII had a slight gradient to the top - which is in the direction of Exeter so it's evidently letting in just a little light pollution unlike the other two filters.

    I am wondering just how far the Ha goes to the bottom left...

     

    307719326_RosetteNebula.thumb.jpg.6dfd050409359e3ff4871196cb7cabba.jpg

    • Like 10
  10. 7 hours ago, Elp said:

    Great image, you've captured the bow shockwave also. I did this recently and managed to frame Thor's Helmet nebula into the same shot, a bit frustrating as it's quite low in the sky.

    It was your image that made me aware of Thors Helmet being so close. Perhaps this will need to be a work in progress and maybe I’d better try a mosaic 😊

    • Like 1
  11. With the recent clear spell I've been out doing my usual coping in the cold with lots of food, hot drink etc etc and doing some imaging.. the imaging being somewhat secondary to the eating methinks.. I've got a couple of southern targets I've been trying to do for years and every time I've tried something has gone wrong.  My efforts with the Witches Head aren't looking great (horrific gradients) but I've managed to get something of the Seagull Nebula, IC2177, in Monoceros. Or at least, I seem to have turned something named after a humble, albeit irritating, seaside bird into something that looks like a vengeful Ukrainian eagle ..

    The image was taken using an ASI2600mm-Pro with Optolong narrowband filters through a RedCat 71 all managed by an ASIAir and comprises 25x Ha, 21x OIII, 17x SII subs all at 5 mins, so, just a little over 5 hours in total. Ideally I'd have done more OIII and SII but circumstances get in the way. In fact this object seems to have a fair bit of SII unlike so many other objects.  I've used the Hubble palette for mapping the filters.. (Ha to Green, SII to Red and OIII to blue).

    I was/am surprised at just how much stuff there is to the bottom right and I've actually toned it down slightly as it was overshadowing the main attraction. I haven't done much with he stars, partly time, partly they look OK (bar a few quirkily coloured ones).  I don' think I'll be going back to this one as I've like to get more of the Witches Head, though I fear with the moon returning and spring approaching (honestly, it is) I fear that'll get delayed till next year..

    Just for fun I've put a screenshot from SkySafari showing where the Seagull is.. I know most of you know but some may not... and I didn't know that 'Thors helmet' is just a short way away to the bottom right of this image until a friendly soul pointed that out. Hmm.. perhaps a mosaic is needed :)

    The image has been jpeggerised probably and clicking on it will generally give a slightly higher quality image (I think!).

    James

    1769381645_IC2117-SeagullNebula.thumb.jpg.9c73956190b6dffb4d95285050eec9c1.jpg

    Seagull.thumb.png.61f8317395b4ccc626876e9cdf756521.png

    Screenshot from SkySafari... regrettably the view from my usual imaging spot doesn't look like that...

     

    • Like 19
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