Whistlin Bob

I feel for you a bit here- you're caught on the horns of a dilemma and no amount of good advice is going to make your mind up for you. The reason for that is that both scopes are more than capable of covering your stated needs and more besides, so no-one is going to be able to point out a killer reason for you to jump one way or the other. I got into astronomy 5 years ago with a 200p. I love it and I still use it a lot (5 minutes ago in fact- I'm just thawing out a bit before going back out!) despite the fact I now have a 14" too. I've also used several ten inch dobs and they're a little bit better but not much. In your shoes I would probably go for the extra aperture, mainly because otherwise I'd always be wondering, but if you do go for the 8 inch you'll still have a great scope.

Good to see you back mate. Lots of lovelly images. Of the 2 I like the Hubble version of Pacman.

I uttered an involuntary "Wow!" when opening this. A stunner of an image, beautifully processed.

I caught this one on Christmas Eve. We had a lovely clear night, and although it was very much family time I did manage to sneak out and set the scope running. It was pretty clear nearly all night, so I was able to gather data for all the channels in one night- a rarity in UK narrowband imaging. Details are: Capture details are: RGB (for the stars) – 10 mins/channel – 20x 30 seconds, Ha – 90x 2mins, Oiii and Sii – 75x 2mins. 130pds on HEQ5 with ASI1600mm at Gain 250. I’m normally indecisive about the best presentation, but in this instance the Hubble version was definitely the one to go with, as it really highlights the tadpoles. I’ve also included a Starnet version- it definitely adds some noise, but you can see the faint bits of the nebula much better. I was curious about the Tadpoles- apparently they’re similar to the Pillars of Creation in the Eagle Nebula- dust and gas left over from the formation of the nearby star cluster NGC1893, and the nursery for future star creation. They point away from the cluster because of stellar winds and radiation pressure from it.

This is my second attempt at this composition and some time off over the holidays is giving me time to catch up with processing… This is quite a large chunk of sky between the Pleiades running up to the California nebula. I had a go at this around 9 months ago, but it was low in the sky at the time and I clipped the background to sort out atmospherics and light pollution gradients. It’s been nice to have another go closer to the zenith. The acquisition was as follows: 2 pane mosaic, taken through Altair 183c Pro camera on a Star Adventurer with a Canon 15 year old “nifty fifty” f1.8 lens. I found focussing at f1.8 just about impossible, so it’s stopped down to f2.8. I wanted to get as much of the dust as possible, so I didn’t use a filter and this restricted me to 30 second exposures at gain 1000. Each pane has 120×30 seconds. I then enhanced the California nebula by blending it with some data taken back in October with a 1970s 135mm Soviet lens and an Ha filter. I suspect that the dust could have been made more prominent had I taken this from a darker site, but I was still quite pleased at how much came out. Who needs a telescope? 😆

Very much yes and yes. The coma without the corrector is pretty awful. The SW corrector is also a 0.9 reducer hence the slightly lower f ratio. I bought it with the correct adaptor for my Canon and it just worked with no faffing about with spacers and the like.

To agree with Vlaiv, I bought an f5 Newtonian to get started in AP a couple of years ago, it was perfect for me then and remains perfect for me now. It's a sweet spot for all the reasons stated, just a really good place to start. If you use it with a Skywatcher coma corrector then you're down to f4.5 anyway, which is pretty quick. Also- your HEQ5 will be fine. I also image with a 200p on mine, which I think is right on the limit (slightly over?), but it'll handle a 150mm with no problems.

Thanks Shaun, that's a really kind comment.

Here’s a picture of last night’s full moon. I’ve spent a good part of the today learning some new processing techniques from the page below: How To Photograph And Edit a Mineral Moon | Light Stalking Unfortunately the steps are all in Photoshop, so I had to work out how to do them in GIMP, but it seems to have worked. I wanted to see if I could do this entirely in free software, but couldn’t get the noise reduction to work so there’s a bit of Pixinsight in here, but otherwise it’s all done with free stuff. Capture details are: Canon DSLR on 130PDS – Disc is stack of 30 of 1/500s, halo is a single jpeg at 1/10 sec Processing is: Converted to avi by Pipp, stacked in Autostakkert, Saturation and Layers in GIMP and Noise reduction in Pixinsight MLT.

Lovely images Gina. I especially love the Ha ones- light pollution is significantly more challenging with such a wide field of view and the stronger Ha signal is really batting it down (I'm guessing the Astrodons are helping here! They're certainly doing a better job than my 7nm Baaders over a similar fov). I love the way large fainter areas of nebulosity are coming through.

I use a Skywatcher Coma corrector, but I'm sure the same principle applies. When I realised I was getting Pacman stars, I focused it on a distant church spire in daytime, locked the focus and marked the tube- it was about 6 mm. Solved the problem nicely 😀 Still bugs me that you need to do this, but then again it's a £170 scope that's astonishingly capable so I'll stop my whinging!

I’ve been fascinated by Barnards Loop ever since I first saw a photo of it- an emission nebula that covers a huge part of the sky. In case you’re not familiar, it’s a large loop of gas centred roughly on Messier 42 that encircles good chunk of the Orion constellation. It’s thought to be a remnant of a Supernova from a couple of million years ago at least 100 light years across. I had a go at imaging it last year, but wasn’t especially thrilled with the results, so definitely on the list for another go. Easier said than done when you’re fighting light pollution… I started this on 16th initially with an IDAS light pollution filter and a Sigma 18-55 lens. Unfortunately the lens/filter combination produced some very strange effects, so I took the filter out and stacked 20 minutes worth of data from 40x 30 second shots. I’m to the North of my nearest town (Bortle 5 skies) and so Orion goes right over the light dome from the town- not a pretty sight: I attacked it in Pixinsight with DBE. It’s a good tool, but the mess left behind from this one had me needing to clip the background out to get something presentable. Still- I thought it’d make a good base to mix some Ha over: Next clear night was Christmas Eve. I waited for Orion to get nice and high in the sky and then had a go with a 7nm Baader Ha filter, collecting an hour of data. This really underlines how much LP gets generated by an average urban area. Despite around 95% of the visible spectrum being cut out, there’s still a pretty nasty gradient: Did my best to sort it out, but it was still a pretty noisy image. Final result is below. If I want to get a decent version of this I think I’m going to need to go somewhere darker, but if anyone has any bright ideas for improving this in the meantime, I’m listening!

I think the weather gods were caught out by the speed of the transaction. They managed a heavy shower within an hour of me setting up, but I'd already had a good look by then. It felt like a a big win!!! You were right about the diagonal btw, but it was great once I'd swapped it out. Very nice to meet you 😁👍 My wife did say it looks like a proper telescope! I had to nip into the garage and let my Dobs know I still love them. I did wonder if the AZ4 would manage, but it seemed pretty good- vibrations stopped quite quickly after moving, and the length of the OTA helped it overcome the lack of slow motion cables

As a lover of Dobsonians I've not had much cause to get involved with this thread. However, I've often enjoyed views through other people's refractors at my local club and after discovering the joys of looking at multiple stars over the summer, all I needed was an extra bit of temptation. It duly arrived yesterday in the form of an ad from @johninderby. 24 hours later and I've even had a cheeky first light with some nice lunar views and a good bit of detail on a receding Mars. Not sure I'm tempted to lick it though...

Couple of presentations of ngc7822 between Cepheus and Cassiopeia. First one is HaRGB- 2.5 hours of Ha and half an hour of RGB. I then added an hour each of Oiii and Sii, but no Oiii appeared and I had to really work the data to get something out of the Sii. So it’s a bit rough, but hey ho. Might go for a brighter target next…

I must admit I have no experience of ATIK, although they seem to be well thought of. I've got two ZWO cameras, and I've been really pleased with them. I know lots of other happy ZWO users as well, so that would be a good route 👍

One of those nights where you know from the forecast it isn't going to be great, but you're also suffering withdrawal and go for it with the 14" anyway... Started off with Mars. I've recently discovered that the best view of it in the dob is with a variable polarising filter. It really cuts the glare down and doesn't seem to lose as much resolution as the aperture mask. Lovely clear surface detail and the polar cap still just visible. Kicking myself that I didn't discover this combination back in October!!! Next over to the Pleiades and it's a fabulous sight- lots nebulosity and texture between the stars. Love it. Then it clouds over.... 90 minutes later my son says if he gets his PJ's on the sky will clear and sure enough it did ten minutes later. I can hire him out at if anyone's interested... Transparency isn't so good, but stars can be seen!!! M42 has cleared the house for my first proper view this season. A brilliant sight and we spend some time drinking it in. The main nebula is bright and clear at 55x and really pops with the uhc filter in. It's like having an old friend back. Even the Running Man is quite prominent. Swap over to the 7mm for 236x and the core is like a whole new object, lots of texture in the bright area with the fainter stuff dropped out by the higher mag. The trapezium is bright and clear with E and F stars just about there floating in and out of visibility. Pop the 30mm back in for a trip to Alnitak, but the sky is getting murkier by the minute. I can see hints of nebulosity, but not the dark lane that means I can chalk up the flame. In view of the conditions I decide to look at some brighter stuff. Sigma Orionis a good sight. 4 stars easy. It looks to me like the A star has a companion. Lots of checking and double checking and a bit of a read on the internet- it does have one and was discovered in a 12" scope. In view of the conditions I find it very unlikely that I've seen it, but one to go back to. Has anyone else on here snagged this one? Really good view in any case. Next I had a look at Betelgeuse. I know it's just a big fat red star but I love the colour and so did my son. Moved down to Rigel. I really like it-it's a nice split and a good example of uneven stars without being anywhere near as difficult as Sirius. One last view on the faint stuff- over to M31/2. A nice view, but too murky to pick up 110. Thicker cloud now so scanning the sky to find gaps... Iota Cass- easily found and split. Achird a nice split with some hints of colour. A nice session- shame it clouded over, but a bit of a fix to keep me going!!!!

Hi Kaelig. A lot depends on your budget (as ever!) For the first 2 years I used the 130pds with a 2nd hand modified 600d that I got for £150 from Camera Jungle. Combined with a coma corrector and IDAS D2 filter it worked really well. Lovely natural colours, and deep reds with an Ha filter. Last year my work bonus bought an asi1600mm. This lets me do full narrowband which has been lots of fun, and really let's me play with colours and presentation.

Had this data a while but not the chance to process. I got the RGB and Ha data on 22nd November and then the Sii and Oiii a couple of nights later. I left the Oiii and Sii running overnight, but had to drop a lot of frames due to cloud. Kit was 130pds on HEQ5, with ZWO ASI1600mm to capture Capture details are: 20x 30 sec each of RGB 90x 1min Ha 50x 2min Oiii 55x 2min Sii Presentations are Ha, HaRGB and SHO with RGB Stars.

I've recently seen some superb stuff from OSC CMOS cameras, and they certainly reduce the processing hassle. However, I converted to mono a year ago with an ASI1600 and I really love the thing. Using high gain/low read noise/short exposures with par-focal filters makes the data acquisition just as fast as OSC, and I have the flexibility of full narrowband. It's a great system. If I were to choose again, the only change I'd make would be to go for the recently released 294mm Pro- the performance of the sensor just looks a bit higher than the 1600, which has been out a while now.

Nice to have a play with data we can only dream of in the UK (especially the Oiii and Sii), and then come back here and enjoy other people's interpretations. Here's my first effort this month. After going for unusual colours in the last few months I'd thought I'd try to be a bit more traditional and go for an SHO. Workflow was as below: Stretch each channel Starnet++ on each channel + a gentle noise reduction. Combine straight SHO using Pixelmath. Adjust curves in Hue to move the Colour balance more towards Blue and Yellow Some SCNR at around 50%, leaving a little green in, so it's not purely bi-colour. Extract Luminance, increase contrast and apply as a mask to focus on the brighter elements of the image. Apply LHE to being out some of the structure in the brighter sections and then use the multiscale tool enhance it a bit further. I then use the Dark Structure Script, but I felt that this overdid it, so I mixed the before and after images in at 50% each. Then use Pixelmath to create a star image (this time mixed HOS) and add the stars back in. Then a little fiddle with curves and a gentle unsharp mask to make it a little crisper. Hope you like it

Very nice report- I too am going to miss the Veil, lots of great views this year, the season for it is really six months long with in Oiii filter for the Twilight nights. I'm quite envious of your ability with the SW to move to a BV position- my 14" truss model doesn't allow this and so I need to Barlow my binoviewers to get a view, meaning they're for small targets only. But I do agree that although the view is a little dimmer, when they're dialed in properly it's a fabulous experience.

I find this quite depressing. I recently had a conversation with some work colleagues regarding the installation of very bright LED lights on the street I live on. They were pretty unanimous in their view that it was a great thing. "The light is much cleaner and brighter". "It feels like daylight". "It's a huge improvement". It was clear my objections were seen as an inability to see past my eccentric interests to where most peoples preferences lie. I've little doubt that in a vote I'd have lost. and badly at that. Who wants to look at the night sky when we've got great telly? And night bugs are ugly. I was very good: I didn't stab any of them!

I use the Skywatcher 0.9x coma corrector, but I have a friend who uses the Baader mpcc mk 3. Both seem to work well. The one irritation is that to achieve focus you end up with the drawtube protruding into the OTA which causes Pacman shaped stars. This is really annoying, given that the CC and the OTA are meant to be designed for one another- it's fairly easily fixed though, by removing around 10mm from the bottom of the focuser tube.

Not strictly speaking an astro item, but I only use it for astro photography: a 1976 Jupiter 135mm lens from back in the USSR.