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  2. Let me see if I can find doc for PI for you with description how to do stats on image. Look here for example: https://pixinsight.com/forum/index.php?topic=6328.0 It shows stats window displaying all the needed information (and more)
  3. I agree with all you say - cracking scope for the money and probably my most used scope. BUT !! I would carefully get rid of all the grease you have added - if it gets onto your eyepieces it will be a proper issue. Remove it and put a few turns of PTFE plumbers tape around the threads - it will take up the slack and provide a nice positive but smooth result and without any fear of damaging anything. Enjoy it !!!
  4. Hi guys, I'm still here loitering, despite being quiet of late. Our little bundle of joy has been teething terribly so sleep has become somewhat of a commodity, meaning I have achieved exactly ZERO scope time with the AA102ED-R I'm hoping to get out soon though. My horizons aren't the best so there have been few targets within reach of a 4" frac anyway, but things are coming around and there's always the moon when we're confident a good nights sleep can be had! P.S. I looked at the ZS103 at Kettering and to be honest there was nothing in my eye that justified the extra cost over the Altair equivalent. Yes, it's a robust scope with a quality feel, but so is the AA. The only real distinguishing feature was the livery, which unfortunately I found a little garish.
  5. First of all - I agree with above quote - we can't tell universe how to behave, we can only asses what are the facts. Let me just point out that positively curved finite / bounded universe is not just fringe / made up idea - it is one of the solutions of lambdaCDM cosmology - Einstein's GR equations. For omega>1 we get positively curved bounded geometry. I can offer you another quote that will emphasize my point: "Extraordinary claims require extraordinary evidence". To my mind, claim that something in the physical world is infinite is extraordinary claim. It's a bit like having hypothetical scenario where you have an equation that has multiple solutions and you choose to focus on one particular solution that violates conservation of energy. It would be justified to do that only in presence of very firm evidence that it is so. Why did I use above comparison? I will draw a parallel on the fact that in all our experiments and all our observations we determined that energy is conserved. It is reasonable to assume it is one of the features of universe. We even made it into a law of nature - Thy energy will be conserved! We in fact have not observed anything that is infinite in the universe - everything so far has been finite. We could have similarly coined a law of nature that goes like: It will be within bounds! There might be a clue that flat / infinite solution is not the correct one? This of course does not imply that positively curved / finite universe is correct - we still have negatively curved hyperbolic universe. Also it might point out that we are missing something else in lambda CDM. I'm talking about discrepancy between Hubble constant measurements. Direct observations place this value at about 73km/s/mpc. Observations that rely on lambdaCDM model where flat geometry is assumed (this still does not mean infinite universe - it could be flat and finite, although isotropy would suffer in this case) give results at about 67km/s/mpc. With latest measurements error bars were significantly reduced and we now have great confidence that this is not due to random errors (I believe that it is now 1/10,000 for random error of measurement). People have no clue why this might be so, and some of hypothesized answers to this problem assert that there might be additional component to mass/energy density - like dark matter interacting more strongly with light / regular matter than is currently believed. This would shift density parameter to higher value making it "more positive" - hence omega>1 or positively curved universe - or rather finite / bounded universe.
  6. I bought the Heritage last summer as a complete beginner and I still didn't buy anything bigger, although I'm a bit tempted to do so. It's a great and portable scope and you can see stuff with it. The moon, planets and clusters look great, nebulas and galaxies are a bit fainter but still fun. If you find really dark skies probably they're less faint... I enjoy manual tracking and star hopping with a red dot finder, but for that you need dark skies, if you want to observe from a light polluted location then you're limited to planets and the Moon. The good thing about the scope is that it's very light, cheap, good optics (I'm no expert but they seem good), for storage I keep it in my not very big apartment and it actually looks nice on a shelf. The focuser is not very good, you can focus with it on small mag, but on bigger mag I find it very difficult... I've added some grease so it's better, but still... If storage is not an issue you can get a full tube scope of same aperture which should have similar weight but it's larger as it's not foldable, but should have a better focuser...Also I'd like to have a sun filter which doesn't seem to be a good idea with an open tube... As for the mount I use dome aluminum ladder and an improvised wooden box, it's actually very stable. Sometimes I use just the wooden box and sit on a small stool, that's also comfortable... So whatever you buy it should be fun...
  7. Hi Dean I hope you dont mind, I gave it run through PS this morning: 1) Colour noise reduction 2) Colour noise reduction and Gradient Xterminator to balance background colour
  8. You can do this with a 1 star alignment and for the first star with 2 and 3 star alignments . The mount starts from the home position and then slews to a point in the sky where it believes the first alignment star is based upon date, time and location info entered into the handset. You can then release the clutches and manually slew the mount onto the star, re-engage the clutches and fine tune the alignment using the handset and then accept the alignment by pressing enter on the handset. The handset now has an accurate position from where to find the second and third alignment stars. What you can't do is repeat the process for the second and third stars because that would lose the encoder settings. The home position is only an approximate start point and occasionally using this method can help to improve 1 star alignments. No alignment setting are lost because the handset doesn't know precisely where the mount is pointing until <enter> is pressed to accept the first star alignment.
  9. I think I'm starting to get the hang of it. Went out last night just after sunset to see if I could spot Mars before it set. I did not, it was either too close to the sun to be visible in the twilight glow, or was hiding behind the clouds gathering in the west, or had already set below the level of the local rooftops (or some combination of all three). Regardless, as it got darker Arcturus was one of the first stars to become visible overhead, so I swung the scope to that, fired up Sky Safari and compared the view in the eyepiece to the app. I found I could move around and follow where I was going, up / the same, left / right reversed. Rotate the diagonal and it goes all kinds of funky, so I will make the effort to set a height for the tripod and my chair that lets me keep the diagonal vertical while still getting my eye to it comfortably. Luckily the short tube of the 102 mak is quite accommodating in this respect. It probably already exists (can't believe I'm the first to think of it) but a 'mirror flip' display option in Sky Safari would be a massively useful thing. As would a split screen function. With a tablet one could have two zoom levels displayed side by side, a zoomed in view showing the current view through they eyepiece and a wider view showing the general area at the same time. Or a sky atlas printed on transparencies. Hmm, Dragon's Den anyone?
  10. yeah I think it may be an insurmountable issue tbh. Thinking back to photography days, losing 1/4 up to 1/2 of a stop is reducing the light entering the sensor plane and in such low light, while you might compensate by increasing exposure time or pushing the ISO (sensitivity) you also gain noise. Also each point of light is now much smaller at the exit pupil (went from FoV 110-180) so per pixel on the sensor there's less light and more dark hitting it, hence you may get brighter stars but not so much the dimer or further stars. I was a little surprised the sky was so dark compared to the 2.8mm lens tho, I'd have expected the background luminescence to have still showed the trees for example. Even switching to CS lenses there's few in the f1.x range and they are mega pricey (350 ish) vs the more available F2.x ones in the £45 bracket. So even with the larger glass you still have the issue of not enough aperture so back to the same situation I expect. In fact the F2.x CS lens isn't that much bigger at the objective than the M12 version, around 30mm so not really much gain for 5x cost. I did have a fiddle with brightness etc and turning on WDR and it lightened things up a little but noise made the image less useful. You could make out a couple stars but pretty much not a very usable image. Still, we'll see with the new board module, one difference with the 5MP sensor that's coming in today is it'll have smaller pixels and similar sensitivity. Not expecting a step back to the earlier setup but it might help a little. Wonder how possible it'd be to hack the on-chip OS to push the shutter speed slower as 1/25 is a lot optimistic for night sky, beyond my skillset tho I'd say, am way too rusty on coding these days and these modules can be easy to brick. Its almost tempting to try a hacked USB webcam, but I doubt the network-USB server would handle streaming video, its fine for scanner and small file transfers but doesn't cope well if you push large sustained transfers at it. Don't really want to put a PC out in the shed as it gets way too warm, plus am not sure about a new neighbour esp after the police have visited several times recently...
  11. Alan OK, that's tonight's task. Back to the 12V- connection question. If the 12V- connections to NC1, NO2 and NO4 are for circuit protection should be kept? What about the 12V- connections to NC2 and NO1, which are not diode protection. Are they OK as drawn? Once the connections to the relay board are confirmed I hope to move on to doing a trial wiring up of the system, using a little 12V motor as a substitute for the dome motor and, for the moment, skipping the inter-connections to the Pulsar/Rigel legacy system. Thanks Peter
  12. I was thinking of parting with my Delos 14 because I haven't used it much but after last night I have reminded myself what a super eyepiece it is in the 12 inch dob. The globular clusters M13 and M92 were wonderfully presented and resolved with it together with nice surrounding starfields against a very black sky background
  13. on the trial version of pixinsight. still deciding if im gonna buy it. also use DSS for stacking.
  14. I think Mark was observing in his garden but the galaxy was almost overhead and he does know his galaxies, does Mark
  15. With the ASI1600MM, I think not having a luminance filter would have caused an issue as there would be no IR and UV filtering. Also if the scope can't cope with 36mm filters on a 4/3rds sensor, then it's not really fit for purpose. Exposures were 60 seconds, but the guiding was excellent, in fact I don't think I've ever seen the mount so happy. Probably due to it having such a light payload.
  16. Great report Ed and congrats on getting Zeta Herc ! I've had a mild obsession with that binary star for sometime now. I first managed the split with with a 150mm F/8 refractor, then eventually with my ED120 and now I've managed it with the Tak FC-100. It's a challenging pair alright with it's closeness and uneven brightness and a stern test of observer, conditions and equipment. I agree that it's when you are observing targets that push towards the limits that quality optics show their worth.
  17. What software do you use for stacking and analysis? I believe PI has some sort of statistics window - it should provide such information. I use ImageJ and it has Analyze feature that provides you with min, max, average, median, stddev and such.
  18. Thanks! I am fully on the pragmatist side!
  19. In my case I did as Peter did except that I added OIII to green and to blue since it lies on the border between the two. I make two images, one HaLRGB with OIII to green and another HaLRGB with OIII to blue. I paste one onto the other and adjust the opacity till the blend most closely matches the colour of the LRGB image. If the OIII contribution is excessive I paste it onto the HaLRGB and reduce its opacity. (I work that way round rather than adding the NB data iteratively.) For the core I will also have added Ha as luminance. I don't remember exactly how I did it but since the core is so well separated from the shell, and is circular, I'll have used layers and a well feathered eraser. A purist would make a layer mask but I'm more of a pragmatist! Olly
  20. Thanks all for taking a look at this. Looks like the scope has got to go back. The issues with this scope appear quite prevalent. When you couple this with the fact that the vixen dovetail is undersized and the focuser isn't all that great, it's not looking like a great product launch from WO. You would have though they would have learnt from their previous mistakes, as should have I. I feel sorry for the retailers in all this who'll have a lot of work on their hands dealing with all the returns and will probably end up absorbing some costs.
  21. All booked up too, very much looking forward to it this year. Also, let me throw my name (and Becks') in for any volunteering - especially dogsbody stuff. If you need clearing, tidying, help with the marquee, we're all over it. Cheers Will
  22. Thanks! That is what I also would try first if I have strong Ha and Oiii data (as often suggested by Olly).
  23. From the point of view of testing just the lens surely it would be better to use the simplest imaging train, no filters and no long exposures like 30 seconds should be adequate. Otherwise any number of the other extras could be adding issues to the image.
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