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  2. These two were taken with a 50mm 1.8 lens on an unmodded Pentax K-S1 camera and an old Manfrotto tripod. I shot about 1300x4" lights for Andromeda and 1100x4" for Orion. About 30-40 darks and flats each. Stacked them in DSS and processed with Startools. Any criticism is welcome!
  3. Hi Peter, That sounds great. I live in Corfe Mullen. I'll be sure to check out the Dorset group!
  4. I am tending to agree. With time I think water will soak into the weatherboard, or seep underneath it by capillary action, and have an unimpeded route to both the wall linings and the floor. In my build, I essentially positioned the wall to lie above the edge of the foundation concrete (resting on joists running around the edge of the structure). The wall membrane covering wall and joists then terminates below the top of the foundation concrete. Water running down the cladding simply drips off onto the floor. Your final design with the DPC looks more water tight, but the sleeper will still be sitting in a pool of water.
  5. Nice set of images. I have the same scope/flattener and looking for a better portable mount rather than the Star Adventurer I use with it at the moment. Looks a good combination.
  6. Since no one has asked, what is your budget? What is the maximum you're comfortable lifting/carrying even a short distance? I ask because I have 15" Dob with Sky Commander digital setting circles, but the mirror box weighs 65 pounds with it's full thickness 2" mirror, and after a back injury, lifting it is a non-starter. I would probably point you toward a light weight Dob with DSCs since they are much less complicated than a full blown goto system. Something like the Sumerian Optics telescopes. You could leave it partially assembled when using it at home for brighter objects, and completely disassemble it for transport to dark sky sites where you could actually see galaxies.
  7. Practicality is most important for me. I have a lot of light pollution and need to carry my telescope several times around the garden to dodge lights. And when I'm finished, I have to carry it inside over a small step. I can't imagine doing this with a 20 inch dobson, so for the moment I'm stuck with a 100mm refractor and a 15x70 binocular. I am looking at something bigger and I have the impression that a 8 to 10 inch dobson is the sweet spot between cost, size and weight. Especially the 8inch is remarkable portable for such a aperture! But I'm rather immune for aperture fever and my next scope will probably be a 150mm refractor, which is less practical than a 8 inch dobson, so I'm contradicting myself ;-) But try to see a 12 inch dobson in person. They are rather hefty pieces of equipment and a online picture just do them any justice.
  8. I found one person, who has both, and does not see any difference in terms of guiding... but he has not specified a lot... @vlaiv helped me with the last question about Peak to Peak error, but .... I had no reply, probably as I forgot to Tag/Quote him... Maybe you guys will be more lucky https://www.cloudynights.com/topic/607897-cem60ec-or-cem120-no-ec/?p=9234049
  9. I would say that the 6 inch RCwhich I have owned in the past was beyond the mounts and many peoples ability to guide, mine for sure, it has been done but by people that know what they are doing It is a slowish F 9 scope and has a F/L of 1320mm I think, you can buy focal reducers but this is all extra cost. I was always advised to keep below 1000mm F/L, there may well be some that would say this is too high to start out with. This is one of the reasons why 80mm refractors are quoted with F/L around the 500mm mark, I don't see why it has to be a Espirit, many use the ED version and produce fine results. Alan
  10. They're Here Plus other updated and new SX Trius cameras.
  11. Has anyone owned or used both the CEM60 and CEM60-EC and compared the two as far as guiding performance? I've seen guiding stats from people who've owned one or the other, but not really much from someone who's had a chance to use both and compare. Reading various threads it seems there's split opinion on whether the RA encoder is worth the extra cost over the CEM60 if you are guiding. Isn't another consideration however, the increased spec for PE from +-5" p-p to < 0.5" rms for 5 min. Which firstly raises the question, one says peak to peak, the other RMS and for "5 min". Are these two specs directly comparable? If they're directly comparable and given that a sharp spike that was still in spec would be <0.5" and able to be guided out (depending on pixel resolution). Where as with the non EC a sharp spike could be up to 5" and still seen as in spec, although I've not seen anyone reporting anything like that bad, it feels like worth including in any decision? One other question, the specs say "60 lb (27.2kg), exclude counterweight*" does that mean you need to consider the 21lb counter weight leaving 49lb for OTA/other gear,or that the 21lb counterweight can be ignored and the 60lb is available for OTA/extra counterweights? Would extra counterweights be counted towards the 60lb?
  12. Thanks to all who showed an interest, item now sold
  13. Hi all, Having read a fair bit of this thread and also being impressed by the quality of the images, I am very tempted to buy a 130 PDS and give it a crack ! A couple of questions though and I apologise in advance if these have already been asked ad nauseam. I have enough money to invest in a HEQ5 pro. I also have enough to put my first steps into mono ccd imaging. I don't have enough left over for the recommended 80mm esprit, so I thought I might have a go with this impressive scope. 1) I will need to saw off the focussing tube from the get go ? I find this a little bit scary. 2) do you need to do the sawing if you buy a 150 PDS? 3) this scope vs a 6 inch RC? any major differences? the thing putting me off the 6 inch RC is the reduced FOV. Is this necessarily an unsurmountable issue? 4) can you please recommend a ccd mono camera that will not under/over sample with this particular set up? So many questions !! Thankyou one and all and clear skies ! Andy
  14. Welcome James There is a Dorset group on SGL and we get together to observe/image from time to time. There are also a couple of local clubs if you are interested in attending. Whereabouts are you based? Clear skies Peter
  15. I have the CGEM and I'm very happy with it... much more managable... much cheaper.... great mount, even for astrophotography upto 2000mm FL. Look at the CGX-L mount if you're wanting to spend that sort of money... if I'd be looking at upgrading, this is the mount I'd be looking at.
  16. That's essentially what I did with my previous obsy. I used a plastic DPC as a skirt running from under the lower shiplap and down over the sleeper.
  17. I would add a yes to this, I've had mine for a year and have been using it with a William Optics Z73 to great effect. I think it is hard to beat in terms of performance vs. weight vs. cost, if you are looking for a portable or beginner mount, as I was. You can see images from the setup from the Astrobin link in my signature...most of the pictures are with the CEM25P. Autoguiding is a must, though, 45 seconds was the most I could bear unguided, although I've seen some people get amazing results with 2 minute subs. Seems robust - used it in winter temperatures of -5C and also took it with me to Mauritius last year (I live in the UK).
  18. If you click the N, S, E, W or Z in the bottom right of CdC it will always switch to AZ mode and require manual switching back to EQ. It's my biggest irritation in this otherwise awesome program.
  19. oops, I meant I apply the MLT at linear stage, not non-linear. Will amend my post above
  20. Hey cool, thanks for the reply. I just pulled the trigger on it! Got any photos of or from your setup?
  21. I've been getting decent results with Straton recently, I use it for tonemap combining narrowband images. I think the key is to use Straton to produce the stars, then subtract the stars from the image in PI or PS. It's a bit long-winded though. Here's what I do, from memory since I'm at work and don't have a Straton screen in front of me: - works in both linear and non-linear - open the image in straton - open the same image again, as the reference image - set the stretch slider to suit so you can see what you're doing, think it's top-middle ? - there's a slider bottom right that I think goes from remove more stars to preserve more nebula, or something like that ? Set it all the way to the right. - in the menu, remove stars from the image - then zoom in a couple of times and go all over the image looking for stars it's missed, you can remove them manually, I think there's a clickable tool for that, or is it alt+click on the star ? Might have to do it 2-3 times on stubborn stars. The undo tool doesn't work, just makes a mess. - once done, there's a menu option that says something like 'subtract image from reference image' - do that, and you'll just get the stars and nothing else - save it and close Straton, then load that star file in PI or PS or whatever. - zoom in again, looking this time for anything that looks like it's not a star, comparing to the raw image will help, and clone-stamp it out, prevents bright bits of nebula getting removed - once done, you can then subtract that star image from the raw image in PI or PS. Key is that 100% subtraction seems to over-do it. So in PI, use pixelmath and do something like '$T-0.995 * star_image', or I guess in PS you would add the star image as a new layer, blend mode subtract, and opacity 0.995. Tweak that 0.995 parameter to suit, too low a parameter will leave lighter bumps where the stars were, too high will leave dark bumps, get it just right and they'll disappear. - you might have issues cleanly removing really bright stars, halos or newt diffraction spikes.
  22. I didn't know about the Microsoft option - I've been trying mirrorop (not necessarily foc).
  23. I thought I’d share this from last time I stripped it lol Every time I always swear it will be the last time
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