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The Admiral

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  1. Does Nexstar SE mount work right handed?

    Well, of course in my case I was just using a single object alignment (the sun), so there was nothing telling the mount that 'up should be down' if you see what I mean. One would like to think though that with a 3 star alignment it should recognise the set up and model accordingly. Perhaps it just doesn't work like that. Interesting to see what Celestron have to say. Without a settings or mode change though, I can't see it working for solar. Ian
  2. Does Nexstar SE mount work right handed?

    When I used the Nexstar with my solar scope with the arm to the right of the 'scope I could never get it to track. Not a problem with the arm on the left. I should have thought it a simple switch to make it work, but I never found a way. Ian
  3. IC 1805

    That image has an impact! Nice. Ian
  4. A Magnificent Saturn.

    A gorgeous image of a beautiful object. I never cease to enjoy your images Avani. I do agree with Dave though, you must have access to space missions to get them! Ian
  5. The "No EQ" DSO Challenge!

    I think it's come out rather well Shaun, but like Fabien, I too find it strangely noisy. As Neil says though, a bit of noise reduction on the image could work wonders. But, where is the noise coming from? I would guess that apart from benefiting from an increase in the number of subs, you should think about increasing the number of darks significantly too. It is oft said that you should take as many as you can, at least the same number as lights. The reason is that you are subtracting one noisy image from another, and the net result is that the noise will be combined and therefore increase. By taking as many darks as you can the noise introduced from that component will be minimised. Likewise bias frames I think, but to do that takes no time at all given the short exposure necessary. It is a chore I know, and that is why some of us are not bothering with darks and just using the bias frames as a substitute. If you are using a DSLR the value of dark frames is questionable in view of the lack of temperature control and stability throughout the session, and the fact that dark noise is very sensitive to temperature. However, on the other side of the coin its use does allow correction of the gross artefacts such as amp glow. Incidentally, this particular subject benefits from short exposures in my view because of the star brightness could be overwhelming. Ian
  6. Altair Astro anyone recently?

    You could try Tring Astro, though that 'scope is not stocked and is shown as £0. Other suppliers are available. Ian
  7. Noctilucent Clouds??

    Thanks all. Never mind, but from what you are all saying the "electric blue" should be instantly recognizable. I must keep looking out for them. Ian
  8. Noctilucent Clouds??

    I've not seen noctilucent clouds before, or perhaps I should say, I've not recognised them as such before. But it seems a fine line between clouds which are just lit from the earth's reflected light and true high level noctilucent clouds. I spotted these at the end of August, towards the West, about 9 o'clock in the evening, about an hour after sunset. I managed to run off a few frames, though by the time I did that I think they were beginning to fade. It looks as though some were vapour trails though. Would anyone care to say if these were noctilucent clouds please?
  9. DIY large inexpensive flat field panel

    I'm not sure how effective it would be to use a series resistance when using the driver, as the drivers are constant current devices I believe. I eliminated the driver and used a low voltage dc source. By all means try adding absorptive material, with RGB it could well work, but I use a OSC camera. With my set up it is a dc supply so the light doesn't (shouldn't) cycle. A bit puzzled by the linked one giving banding though, as it's driven by the USB. On the other hand, if it's an electro-luminescent panel, these operate at a significantly higher voltage I believe, so perhaps it contains an hf transformer to step up the voltage. Ian
  10. DIY large inexpensive flat field panel

    Yes, I constructed a similar flats light but using a smaller circular LED light panel. Internally, they consist of an annular strip of LEDs on a tape (see my posts https://stargazerslounge.com/topic/265275-low-cost-light-source-for-flats/ and https://stargazerslounge.com/topic/274057-flats-light-final-chapter/), and do give what seems to be an even light. And yes, they are very bright, so much so that I had to find a way of reducing the intensity. Commonly used LEDs have a spike in the green part of the spectrum, and so using semi-opaque filters ends up shifting the spectrum towards the green. In the end I did away with the mains driven 'starter' unit and drove the LEDs with a low voltage DC. By adjusting the value of the series resistance it was possible to bring the intensity down to a more sensible level. Good luck with your build. Ian
  11. Printing Pictures

    A calibrated monitor really only ensures correct colour and allows you to set a known brightness level. However, depending on the illumination level inwhich you are viewing the screen, the brighter or darker the image will appear. In other words, getting the level right is difficult to standardize. I print myself, so if it's wrong I can adjust as appropriate, but if you send off for a print then it will all be bit uncertain. Some commercial printers can send you a standardized test print, which you can compare with how a downloaded file looks on your system (Photobox, for example). I don't know if some printers measure the average brightness of the image to set their print density, but of course astro images are not standard scenes, having a much higher proportion of black. I'm sure there are many here who've had satisfactory results, and can recommend printers. Ian
  12. The "No EQ" DSO Challenge!

    Well I think you shouldn't be disappointed with it, the core is well defined and the lanes are visible. But a bit more information about the image would be helpful, such as scope and mount, camera, number of exposures, exposure length, any darks and bias frames, stacking and processing software. If you take darks, make sure that you take plenty otherwise they can add noise. And yes, flats are probably more important. Ian Edit. OK, I see there is some info on the linked image, but it's quite helpful to have it on the post as well.
  13. The "No EQ" DSO Challenge!

    You've done well to get that Shaun. I didn't find it the easiest of objects, and I should think my Oxfordshire skies are rather darker than yours. Interestingly, your spikes seem pretty sharp considering field rotation and it being a combination of 3 sessions. Ian
  14. Linux for a Dummy

    Sorry, can't offer any advice there, I'm at the end of my knowledge base! It is odd though that you've got wi-fi up and running yet can't access the internet. Could it be related to the type of security encryption you are using? Just a wild shot in the dark. Ian
  15. Linux for a Dummy

    Well done Alan. When I tried Mint on an ancient laptop from a DVD a few years ago, I was amazed to see that the wireless network was viable! From what I've read, getting the wireless network can require a bit of work. What distro are you using? When I downloaded I am pretty sure that the image was already bootable, IIRC, so I didn't need to go through the rigamarole of converting. Wasn't there an option to download an already bootable image direct to the stick? I get the impression that modern computers are a bit like cars, no longer designed to be fiddled with by the great unwashed! Ian
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