Whistlin Bob

The 130pds strikes again! This is from 28/10, imaged under a 94% moon. I did this one a year ago and accidently cut off the bottom, so it's always been on the list to go back and have another go. This is a HOO blend using the ASI1600MM Pro, with 80x60sec at gain 250 on both channels.

This might be a bit lurid for some tastes… I always think that since we’re doing false colour anyway, why not really push the boat out? I understand that there’s a bit of a convention around naturalistic and SHO palettes, but its fun to play around. Processing of the channels is as per the versions above, combination is then as below: Red Channel = Sii Green Channel = Oiii-Sii (to make both stand out) plus a little Ha to give a bit of Cyan to the blue. Blue Channel = Ha – sum of Oiii and Sii (to stop the Ha totally dominating where other gases were present, but allow me to get a strong signal in the fainter areas of Ha).

Another marvelous set of data. I decided to go away from my usual workflow and process each channel separately as far as possible to bring out the best in each channel and then combine. The process on each of the channels was: Gentle de-noise in the multi-scale tool under a luminance mask (Oiii and Sii only, no discernible noise in Ha channel) Masked Stretch using area of reference on each channel Star removal with Starnet Fix a few leftover star artefacts Stronger de-noise to resolve noise introduced by Starnet Create a “Stars” image for each channel by subtracting starless from star Gentle convolution of 4 and 8 pixel scale under a luminance mask protecting the darker bits. A bit of LHE to enhance the contrast under the same mask. Channels now ready to combine, but Ha was much stronger than the other 2 (as it usually is) and I had a choice between toning it down a bit, or finding another way to avoid it drowning out the other 2 channels. I decided on the second method so that I could retain the strong signal of the top left of the picture. First version was intended to be natural-ish. Combination was as below for the nebula and a simple HOS for the stars. Red Channel = Ha – sum of Oiii and Sii Green Channel = Oiii Blue Channel = Sii + Oiii weakened There was no real science behind this, just trying to find a combination that I liked after the initial simple SOH combination looked a bit too raspberry ripple for my taste.

Here are a couple from this week. I've recently acquired a fan-cooled Altair Hypercam 183c, which with it's tiny pixels and light weight is a great partner for the Star Adventurer. At the moment I'm partnering it with a vintage 135mm m42 lens which seems to work well. We've had a very bright moon, so I've had the Ha filter in. This one is a mono presentation of the North America and Pelican nebulae, 80x 60 secs with gain of 600. Here's a 110x 60secs on the California nebula. I've cheated a bit on this one- it's purely Ha, but there was a bit of signal on the blue and green channels so I de-saturated the stars to give the appearance of RGB. I've also made the sky darker than usual as I had some mutant godzilla sized dust bunnies.

I think they're teasing us! Yep- we got loads of data... we'll release it sometime... 🤣

Recently I’ve been struggling for ideas for visual observing. When there’s a clear night I keep going back to the same old targets, and whilst this is enjoyable, it doesn’t carry the same excitement of discovery. I think the root cause of this is not doing the leg work beforehand- I normally build target lists (often from other’s observing reports), but I’ve dropped out of that habit a bit of late. A couple of days ago, whilst contemplating a tricky work problem I picked up my old battered copy of “Turn Left at Orion” and started flicking through. In my first year of observing, it was this book that really got me going, giving me target ideas and helping me to find my way around the sky. As I’ve become more proficient it has gradually fallen out of use, but flicking through it I found I’d done what everyone probably does and gone straight for the showpieces. There are a wealth of other targets along with nice little narratives. So, last night I worked my way with my 14” dob through pages 180-189 of my 4th edition. I used Sky Safari a little to help with the navigation (it makes it so much easier), but otherwise this is a session done Old Skool! Mars: Alright- this wasn’t on the list, but you can’t ignore it, sitting there so prominently. I’ve become a bit spoiled in this apparition, having had quite a few outstanding views of it. Last night was a bit murky in comparison with the best of those, suggesting thin cloud, but I was still able to make out shading on the surface and the distinct solar cap. It’s been a wonderful target these last 6 weeks and I’ll really miss it when it has receded. Almach: Incredibly I’ve used this star to navigate many times, but never actually looked at it in the eyepiece. What a beauty! Very bright and to my eyes it looked blue and almost white with a hint of yellow! 59 Andromeda: Like two blue cats eyes, nicely separated and evenly matched. 56 Andromeda: This pair was a touch fainter and a less vivid colour, but more of a golden colour with a wider separation. It took a bit more finding, sat on the edge of a relatively sparse open cluster NGC752. With hindsight, I was sticking too closely to the script here and should probably have dropped in a wider eyepiece to enjoy the cluster more. The Baader 8-24 zoom I was using is very good for dropping in and out, but the narrow FOV at 24mm doesn’t give the best view of extended objects like this. 6 Trianguli: A much tighter pair at 3.7”, but quite easily separated at 8mm. Lambda Arieta: A nice contrasting brightness, TLAO talks about contrasting colours but I can only see a hint of blue in the much fainter companion, whereas the primary seems completely white to me. 1 Arieta: Another tight pair at 2.9”, but quite easily separated at 8mm. Again, I was unable to make out a colour contrast. Mesarthim: A more comfortable split and a much brighter double star, apparently even brightness (combined mag 3.86). According to TLAO the orientation barely changes, suggesting that we’re looking at the orbit edge on. I was curious about the name of this one so researched a bit further- apparently it’s a corruption of nearby Sheraton; and as a star it appears in Chinese and Indian Mythology; in the latter as a doctor to the divine. It also gives its name to an Australian band who specialise in the Depressive Suicidal Black Metal genre. Who knew that was a thing? I’ll probably give it a miss… M34: Turn the page and here was a more familiar object. To me it looks sort of like a flower stalk, set against the rich star field of the Milky Way. This time I did drop out to the 30mm- a really nice view. The Double Cluster: Here’s an old friend, it even looks good in the finder. Sticking with the 30mm I was comfortably able to fit both sides in the same FOV. As well as the richness of the Star Field I love the different colours in this one. There are lots of tones of yellow and blue, and then a few deep red ones really stand out. Found myself in disagreement with TLAO here- it claims this is much prettier in a smaller telescope (a 4/4 frac view, but only a 2/4 dob view), but I find the view in my Dob for this one glorious- the number and concentration of the stars make this one of my favourite sights. On the other hand- I do like the way TLAO descriptions lapse into the whimsical- “the view from a planet in one of the clusters would be spectacular: perhaps a hundred stars in the home cluster would be far brighter than the brightest star in Earth’s sky, while the other cluster would be far more impressive than any open cluster in our sky”. Now there’s something for your dreams. The Pleiades: Having the 30mm in the scope and talk of spectacular open clusters made me take a detour to the Pleiades. Perhaps natives of the Double Cluster have a better view, but this one does me just fine. The electric blue colour and patches of nebulosity still visible even with the strongly illuminated moon. Yum! Back to TLAO… Iota Cassiopeia: This again is a familiar target; I find it a good test of conditions, especially when the Double Double is dropping low. I quite enjoy pulling it up at 24mm, when it looks elongated but single, and then zooming. At 20mm it’s already a double, but I’m at 10mm before the third companion starts to appear. By 8mm it’s a clear separation. Sometimes I can see hints of colour, but tonight they all look white. Struve 163: Another triple, but much greater separation. The A and B stars were showing fantastic colour- deep blue and orange, although the third was much fainter. This was another discovery for me, a lovely sight, I need to make this a regular stop! Eta Cassiopeia: Another pair of contrasting brightness, I found this quite a straightforward separation. TLAO claims sharply contrasting colours, but I couldn’t get this- just a hint of orange in the secondary for me. Burnham One: I struggled to find this one a little, and didn’t manage to split the A and B pair (1.1”- which is usually just in range for the dob). I should have tried a mask, but was more excited that the transparency had improved a bit and some clouds to the south were dampening the moonlight to the extent that I could see the PacMan nebula- something I’ve never managed from home before! Sigma Cassiopeia: This, at 3.2” was an easier split- the clouds were coming closer now… Struve 3053: Last view of the night and another new one for me. I had to be quick with the star hopping to beat the oncoming clouds, but got there just in time- and very glad I did. Quite startling orange and blue- a really lovely view. The encroaching clouds ended it there, but really enjoyable to get the buzz of discovery back. I would happily have turned the page for a tour of Cassiopeia’s open clusters, but that’s going to have to wait until the next time!

Congratulations on your 300p @BiggarDigger- sounds brilliant. I umm'ed and aaah'ed about a bigger scope for ages before taking the plunge. I've never regretted it for a second. @procky1845 many people said the same to me- "you'll just pick up more light pollution" and of course this is true. But everything increases at the same rate and so on fainter objects, there's more light altogether and you still see more of the object. I have a 200p and a 350. In equal conditions (and I've used both scopes in Bortle 2 up to 6, home is Bortle 5) the 200p, good though it is, gets blown away by the bigger scope. The downside is that it's a big beast and takes a while to assemble and collimate, other than that it's brilliant!

Love M33 as both a visual and imaging target. This is from two years ago, I think 3 hours of 5 minute exposures on a 130pds with a Canon 600d and an IDAS D2 filter.

It has taken me ages to get this one into a state where I'm happy with it. I think part of the problem is that the IKI observatory published their data on the same target on the same night I was imaging this. I've been having a lot of fun playing with their data, and when I started on my own data, my little reflector felt a bit outgunned. Think about it: Not only that- they've got 80 hours of integration time under a dark sky. I've got 3 hours in suburbia. With LED streetlights. You can pop over to the IKI thread to see how their data turned out, but all things considered I think the 130pds acquitted itself pretty well. My data was: 20*30 secs each of RGB for the stars, 60*60 secs Ha and 90x60ses Oiii all at gain 250. The channels were mixed HOO, with the Blue at 150% to give the oxygen envelope around the nebula a blue tone. I had a lot of trouble trying to balance the brightness of the crescent with the background nebulosity- in the end I did two versions in Pixinsight, one for the Crescent and one for the rest and then merged them as layers in GIMP.

I have a 200p that I use for imaging and I use Skywatchers own coma corrector- for visual the coma isn't really had enough to trouble me, although others don't like it. It works well with both DSLR and dedicated astro cameras, plus gets me imaging at f4.5. I do sometimes have reflection issues with NB filters and very bright stars that are worse when the cc is in the image train.

This. It doesn't make an enormous amount of sense to me, but I have found it to be completely true. M33 was an object that I failed to see at home for a very long time, despite pretty strong equipment and many attempts. Then when I did find it, it was quite underwhelming. But over time I've had a few really good views, and I'm pretty fond of it as a target. I guess it must be simply that you learn what works and what you can expect from the sky conditions on any particular night.

Well done to the winners and everyone who took part 👍

I use very think heat holders gloves with the tips of the thumbs and right first finger snipped off and sealed with duct tape (!) Cheap and works very well!

What a brilliant project and beautiful scope. Thank you very much for sharing.

Couple of different processes of the Wizard nebula. The acquisition details are: R,G,B – each 20x 30s (Stars) Ha,Oiii,Sii – each 100x 60s (Nebula). All at Gain 250 on ASI1600mm with ZWO filters, HEQ5 with, of course, 130pds using SW Coma Corrector. There’s 2 presentations: the first is SHO, but with the green channel then mostly re-distributed into yellow and blue, the second is more naturalistic with Ha and Sii fed into Red and Oiii into blue and green, with a 50% multiplier on blue and a reduction in Red where Oiii is present. So not very naturalistic!

Here's my HOO effort. Exactly the same technique as my SHO version above, but with the channels fed as follows: Red= Ha at 100% Green = Oiii at 75% Blue - Oiii at 150% Plus I didn't desaturate the stars. I was happy with the colour mix compared with other combinations I tried, but then looking again at some of the others here, have I made mine too blue? I think you could process and re-process this indefinitely with different tones and hues!

Great write up... making me wish my bins had filter threads!

Like a few others I found this one a bit trickier to process than the M16 from last month- despite the strength of the data. I've played with SHO and HOO on this; I preferred the SHO, but might try and do a HOO as well if I get some time. The process I used is below; this is all in Pixinsight: - Rotated Ha image to the direction I prefer then registered the other images to it. - Clone each channel and stretch them to mask for Noise Reduction (though noise was fairly minimal) - Use Multiscale Linear Transform for noise reduction, quite strongly at single and double pixel scale (threshold of 3 and 3 iterations) and gently ay 4 pixel scale (1 and 1) - Masked Stretch on each channel - Bit of curves to enhance them further. - Clone each channel, create a star mask, invert it to protect the stars and then remove the nebulae and smaller stars. - Apply Starnet to the original channels to create Starless version - Combine the Channels as SHO - I usually try and use Hue and SCNR to give a less green / more golden appearance, but it really didn't seem to improve this data. - Instead, I held the green and red (there's not much Sii in any case) and boosted the blue to stop the green being completely dominant and try to enhance the lovely oxygen envelope around the Wolf-Rayet shockwaves. - Luminance mask and another round of noise reduction similar to before. - Invert the mask and enhance detail; I found the MLT didn't work well on this data and so used a mild Local Histogram Equalisation instead. To be fair- it's pretty sharp already! - Finally, add the stars back in- I couldn't get colours I was happy with on this, so I mostly de-saturated them instead. Again- it's been a pleasure to process such strong data and to compare what I've come up with to other peoples images. It's really interesting to see how different peoples preferences are. Looking forward to the next data release!

Thanks Gents 😀 @Mark at Beaufort the planetary observations were largely in the WO Binoviewers that you sold to me. They can just about focus in the Dob with both Barlows and give really terrific high magnification views.

I really wasn’t expecting much last night after our local club zoom meeting (Tom Field from Seattle talking about spectroscopy- very recommended), as the forecast was iffy and I was tired. It was only my son nagging that got me out really. I’m very glad he did. Got the 14″ out (in for a penny…) and started off with some broken cloud and a nice view of Mars- it really is very good at the moment. Polar caps and surface shading were very prominent- and that colour- wow! Decided to try and do an imaging run in the Dob on it- it’s harder than it looks!!! I barlowed it up to get some detail, and at 5m focal length keeping it on the screen, never mind in the middle, is not easy!!! Eventually realised that the seeing wasn’t going to support anything special so we abandoned that idea and started observing instead. Next went for the Pleiades, and at that point the penny dropped that seeing might be a bit wobbly, but the sky was very transparent. The nebulosity was evident all over the place, a bright electric blue around the brighter stars. We both found that by gently wobbling the scope you could bring out the granularity right across the cluster. Moved across to Andromeda, and just sat taking turns drinking it in- with the bright core centred the disk reached out beyond the fov of the 30mm EP. Even m110 was pretty straightforward. Time for my son to go to bed, so I said goodnight and then took a break to set an imaging run going. Next up- Uranus- clear green disk. Lovely view. M33 best ever view from home. Superb in 30mm. Core was clear with hints of the outer regions. Ngc752 lovely rich cluster. Almost rose like. Gorgeous. NGC 891 – Nope- even with this sky I couldn’t catch this at home. I fancied some more galaxies so next up was Mirach and its ghost. At around 200x this was clearly visible. NGC 7814 in the corner of Pegasus was really faint but there. Ngc7331 above the north west arm of Pegasus was nice and obvious. Worth going for Stephans quintet? YES! First sight at home in 30mm just a smudge, but definitely seen. Spent a long time on this one. I must have tried for this 10+ times but I’ve only seen it once before on a special night in Cumbria. It was only the faintest lightening of the sky without real shape, but the concept of seeing this galaxy cluster with my own eyes blows my mind. Over to Cepheus for the Garnet star- like a glowing coal, with hints of nebulosity around it. Ngc7380- my imaging target for the night. No nebulosity seen but a nice v shaped cluster. Caroline’s Rose. This was inspired a bit by a clubmates picture. On hazy nights I find this cluster can be a bit meh- but tonight the hundreds of faint stars were a wonderful sight. Time for bed now, but went back for a last peak at Mars. Just a terrific sight. I spent a while looking for the moons without any joy- the planet was just too bright, the glow prominent even when the disk was edged out of view. Tearing myself away from the eyepiece on a night like this was not easy!

I actually would take a Star Adventurer, DSLR and a couple of lenses and try to get some 135mm'ish images of the core of our galaxy, the bits that are just too low for me to get at home. Then I'd just scan the skies and drink in the view whilst it clicked away. I'd probably get tempted by a closer up view at some point, so I'd need some binoculars. It'd either be Cygnus that did this to me, or that run down from Altair through the Wild Ducks to M17. Then I'd lose it altogether and need a big Dob. Probably that same area- it's really hard to get from home, and some quality time with a bit of light grasp and height in the sky around that bit would be really something. Did you say we could take a truck?

That's familiar! One of my favourite astro upgrades was a blackout blinds for the bathroom! Really liking this thread. I started working through the Messier's myself a couple of years ago, but got stuck in the last 20 it so that are in the South during summer where it's hard for me to see them. Good luck with this and keep us posted 👍

Lots of debate on focusers here. My experience is that the standard one works well with DSLRs but struggles a little with the weight of camera and filter wheel in a dedicated set up. However, with a bit of fiddling (making sure everything is adjusted well and locked once focus is confirmed) I think it does cope. The photos below all came out of an ASI1600 with filter wheel on the standard focuser.

That's gorgeous. Lovely detail and very well processed.