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  2. 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.
  3. 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?
  4. 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...
  5. 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
  6. 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
  7. on the trial version of pixinsight. still deciding if im gonna buy it. also use DSS for stacking.
  8. I think Mark was observing in his garden but the galaxy was almost overhead and he does know his galaxies, does Mark
  9. 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.
  10. 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.
  11. 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.
  12. Thanks! I am fully on the pragmatist side!
  13. 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
  14. 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.
  15. 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
  16. Thanks! That is what I also would try first if I have strong Ha and Oiii data (as often suggested by Olly).
  17. 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.
  18. Last night was clear in SE Essex, but I nearly didn’t go out, not long past full moon and the lingering twilight. However I’m so glad I did because it superb for double stars. The highlight for me was Zeta Herculis ( Struve 2084 ) the SW star in the keystone. I had two scopes in use, my OO 10” Dob designated 1/4 wave, and a new to me OO 8” VX8L, designated 1/10 wave. I’ve had many unsuccessful tries at splitting Zeta with the 10” and last night was no exception. Last night the seeing was so good that I tried magnifications that are usually pointless. With the 8” at 300x and then 400x I got a lovely clear pin point split. Bit of a challenge hand tracking at those mags with the 50 degree apparent field zoom, but definitely worth it I wont go into what 1/4 wave and 1/10 wave actually mean, different interpretations about that.......... Both scopes fully cooled and collimated, chuffed with the 8” previously owned by a local club member sadly no longer with us. Ed.
  19. thanks, where do you find the pixel values for an image?
  20. Göran, I always create an RGB image as normal and then add the Ha to red and OIII to blue in lighten mode
  21. Nice and people say Maks are only good for planets and lunar.... Alan
  22. Strange, there shouldn't be much difference between f1.8 and f2. OTOH I found the Fujinon fish-eye lens 1.4mm and f1.8 let in a lot more light than the 1.55mm f2 lens which is considerably smaller. I suspect focal ratios on fish-eye lenses mean something different from "normal" lenses and telescopes.
  23. Superb images both of them, and this is a question to both Peter and Olly: How did you mix in the NB data to the RGB? Just Ha to red and Oiii to blue? Or did you only use the RGB data for the stars? Göran
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