carastro

I have posted this on another thread, but it seems sensible and relevant to post it here to show comparisons. This is my M20 image processed in my normal way a few months ago. This is the same image I reprocessed today using Mark's Arcsinh method. I am well pleased with the improvement, I always struggled with star colours, but it's even produced a better overall colour in the image.

Brilliant Mark, it works and I don't have to buy Pixinsight. Carole

Well maybe fast optics might make a difference, but I could never see nebulosity with my DSLR, even after doing a long exposure I might only see a faint hint of it. Only processing would bring it out. I coped getting focus by marking the drawtube so I knew where the point of focus roughly was each time, but doing it from scratch I used to use the Moon to get rough focus. Once I was close to focus I could actually see a star on live view and then could complete focusing. Well that was my experience. Carole

Having used both DSLR and Mono CCD cameras, my comments are as follows: A DSLR is certainly a lot cheaper and probably a lot less to learn for a beginner. In particular processing is probably more straightforward. BUT Apart from the fact that a Mono CCD camera shows much more detail, it is far easier to see if you have the target framed in the FOV and get focus. I have been helping a newbie recently with a DSLR and I had forgotten how difficult it was to find the point of focus with a DSLR, if you're not near focus you won't even see it on live view, and you certainly can't see the nebulosity. So from that point of view Mono cameras are easier for a beginner. Therefore in summary, I recommend a beginner (if they can afford it) should start with a mono camera and just do Mono imaging for a short while until they get the hang of it all. A filterwheel and filters can be added afterwards. Carole

The guide camera goes in the back of the 9 x 50 finderscope (with a cheap adapter). This removes the finderscope as a "see through" finderscope, but if you use a laptop to capture images you can look at what the finderscope is looking at on screen and this is much more comfortable than all the awkward positions you might have to get into to look through it. As regards the 12D string link, I think they use standard images which enlarge and decrease according to the kit used, so am assuming that the box they are sitting in is the size of the FOV, I must say that has confused me a bit at times, but I find this an invaluable tool when planning targets and imaging sessions. Planets will be small in an ED80 (as stated above), but input the barlow on the left side as x 2. I'd get the outfit which comes with the eyepiece and diagonal and an aluminium case. It's a decent eyepiece and if you buy the finderscope on it's own it could set you back around £80 and the eyepiece about £30, which in the end is going to cost about the same, plus you get a 2" diagonal and aluminium case as well. I re-sold my aluminium case as I didn't use it because of space storing and transporting, so re-couped some of my expenditure. HTH Carole

I had not realised the ED100 was slower than the ED80. In that case definitely go for the ED80 (make sure you buy the APOchromatic version). Buy one that has a 9 x 50 finderscope as this can be converted into a guidescope, nice and light, no hassle with mounting and cheap to do. I use one all the time. If you buy the SW focal reducer @ x 0.85 will bring the focal ratio down to F6.37 Imaging and viewing DSO and the Moon with this scope you will not be disappointed (most DSOs are faint in any scope), but with a larger FOV - depending on what camera you are going to use, you'll get larger targets into the FOV such as the whole of Andromeda galaxy and M42, The Heart Nebula etc etc. If you get a more powerful scope you'll end up not getting the whole of a target in and having to do a mosaic. To be honest you're not going to be able to completely combine planetary with DSO when it comes to scopes, they need different scopes and you will just have to decide which is the most important to you. Most people have more than one scope for DSOs and planets. If you want to put your mind at rest take a look at this website, you can input the telescope and camera and select various targets to see what you can get in the FOV and how big things are. You can also use it for inputting eyepieces. http://www.12dstring.me.uk/fovcalc.php The ED80 is much recommended for people starting out and is tried and tested. Carole

Sorry, I meant to say I regularly use the ED120 at Astro camps with my HEQ5 and it works OK. So an HEQ5 should be fine for an ED100. An NEQ6 will only be necessary if you plan to get a heavier scope at some point. Carole

I think this is wise advice, imaging is challenging to start with and a smaller telescope places less demands on you and guiding than one with a smaller FOV. However as you are keen to do planetary as well, why not compromise with an ED100 half way between the ED80 and ED120. I regularly use an ED120 at Astro camp with a finderguider (this lessens the weight) and it works just fine. So should be good for an ED100. If you are getting a Skywatcher scope buy the Skywatcher focal reducer with it too. https://www.firstlightoptics.com/reducersflatteners/skywatcher-85x-reducerflattener-for-ed100.html Not cheap but nothing is in imaging. This increases the FOV for imaging and speeds up the optics and keeps everything nicely centred. HTH Carole

The HEQ5 and SW ED80 you linked will be excellent for imaging and visual as well. Perhaps not so great for planets. The 200PDS will be a smaller field of view, so planets will be a bit larger than the ED80, but you would need a bigger mount than the HEQ5 for that, such as the NEQ6. CArole

I think they do but you have to pay for it. When my husband had his eyes lasered at Optical Express there was an option to have replacement lenses. Carole

I have the same set up with my contact lenses. I have a sight lens in the right eye and a reader in the left eye, brain works it out and works a treat. Also I think when my husband had laser surgery they did the same with the treatment of his eyes. Otherwise you would have to keep taking reading glasses on and off all the time. Carole

Congratulations to both of you, I presume you're both into Astronomy then. Amazing cake. Have a lovely day with lots of photos to remember it. Carole

It's Melotte 15, the centre of the Heart Nebula and yes is it narrowband. You can image it in broadband too, though not so sure if it is so defined in LRGB. Carole

Oh gosh, no, I didn't realise it came with a 6 x 30 finder. I must admit I use my SW finderguider from another scope because it already had the camera fitted. But in any case the foot size is the same, so if you can get hold of a 9 x 50 SW finderscope that can be used as a finderguider, nice and light, cheap and no problems mounting it. Carole

I know nothing about statistics, I just do what works. The skywatcher finderscope on your 150PDS will work OK as a guidescope, I had one and that's what i used. No need to buy a guidescope and worry about how to mount it. Just need a guide camera and the relevant finderguider adapter. If FLO can't help I know a retailer who does them but as they are Sponsors of this site I should not post up another retailer. Image I did with it. Bright stars are a bit squiffy as the focusser protruded into the tube too much as it was the 150P version. N.B. These are 900sec subs, so you can see the guiding was OK. Carole

HI Gina, I haven't read every single post on here, but as an owner of a Skypod, I would not think it would be possible to motorise the dome. The moulded panel heights can be uneven and the whole thing can take a real effort to push round at times. Having said that, you get such a huge expanse of sky with the POD that I rarely find it necessary to rotate the POD in any case. The roof has a rubber gasket to stop rain, though it can leak at the pivots either side, but not in the centre. I put a small pot each side to catch the rain. It also prevents imaging at or near the Zenith and i had to build a Table extension to unhook the dome and slide it off (another task requiring some muscle as it's not easy). Whilst I am really glad I have it, if I ever started again, I would not go for a Skypod for imaging because of the need for a Pod Zenith table. Carole

What a fabulous video, really gives the feel of a star party. Also really like the music, very atmospheric. Carole

I use this excellent tutorial by Anna Morris. I think there are other softwares that will do it too, but this will give you the principal of how it works. YOu can do the same with narrowband, substituting Ha, Oiii and Sii for RGB, or Sii, Ha, Oiii if you want to do Hubble palette. http://www.eprisephoto.com/create-lrgb

Didn't do a huge number of images this year, these are probably the 5 best ones: IC410 Tadpole Nebula (Taken from SE London) Dual rig, ED80/Atik460EX & WOZS71/Atik314L Pacman Nebula NGC281 (taken at an astro camp) Dual rig (but put cameras on wrong scopes as was a bit out of practice):Atik460 & WOZS71 Atik 314 & ED80 The Bubble Nebula NGC7635 (Taken at Kelling) ED120 & Atik314L Melotte 15 (taken from SE London) First Light with SW150P & Atik314L M45 Pleiades Cluster First Light with SW130PDS & Atik460EX Carole

I got my 2nd light with my SW130PDS last night. I am planning to get a 2nd night on both of these images if we get another clear night soon. I did Melotte 15 while I was waiting for M45 to rise above the houses. Both images from the Suburbs of London. Carole Mapped HOS Ha 8 x 900 + 1 x 600 Oiii 6 x 300 Sii 5 x 300 WIP SW130PDS, NEQ6, Atik460 followed by: M45 The Pleiades cluster M45 with SW130PDS, NEQ6 & Atik460 Baader CC Lum 8 x 600secs RGB 6 x 300secs binned x 2 each

Very interesting topic, am following this with interest. I am not that technical so can't offer any thoughts except for tilt - if the camera is being locked into the draw tube by only two screws. Then if there is slight tilt on one side of the meridian, then the tilt would be the opposite way after a flip, doubling the error. I am probably completely wrong and probably doesn't apply to scopes which don't use the 2 screw method at the draw tube, but just thought I'd throw that into the ring. Carole

To be honest I have never thought about it, so I am not sure what order I do it in. Processing mono images is quite a different kettle of fish to DSLR images as if the noise is in the Oiii and Sii, I quite often take the finished image and blur it to reduce the noise (dust and scratches) and then paste over the the Ha image for a 2nd time and blend it as luminosity. This will sometimes wash out the colour so I slightly adjust the colour layer in curves or match colour, and then slightly adjust the Ha layer also in curves until the colour gets put back. I think I found that on an on-line tutorial, think it was Starizona. It's probably at this stage I do some selective sharpening which I usually do by taking a copy of the image then do a High pass filter and then paste back the copy on top and then erase the bits I where I want the sharpening to show through, this normally prevents the stars from being sharpened. I know you can select the stars and exclude them from the HP filter, but this tends to select only the brighter stars so the small ones still get High Passed so I find this method works better, does mean you have to avoid the stars when doing the erasing. HTH Carole

Thanks Al. I have now brightened and sharpened it a bit and tried to reduce the noise: