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The Admiral

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Everything posted by The Admiral

  1. It is, and I've given up! In order to 'improve' I'd have to invest money, and I see no point. Well done FLO on this new venture, I hope it's successful. Ian
  2. I use the Nexstar 8SE in Alt-Az mode. All good advice above. I too can confirm that date/time entries are not retained. There is no internal battery in the handset to keep the data in the volatile memory, my mount had this behaviour from new. It is also very easy to enter the details incorrectly. Using AA batteries to power it they can give odd results as the voltage drops so a decent external power supply is really a must, as you already do. I don't use an SCT but mount a refractor on it, with the arm on the LHS of the scope, viewed from the eyepiece end, but I have never initialised the mount with the scope pointing North. May be the SE is different. All I do is make sure that the tripod is absolutely level before adding the mount. There are additional requirements if using the mount on a wedge and operating in EQ mode, such as aligning the index marks on the mount head and aligning the OTA with the meridian. I've always been a bit doubtful of using daylight saving time so I have only entered GMT (UCT). Ian
  3. I'm sure that's the case, but it does represent an increased expenditure. Still, any time spent imaging in AZ does allow one to increase one's knowledge and hone one's skills in processing, so it's all time well spent. I found the ability to image without access to the NCP so much easier with AZ, not to mention the quick set-up time. I don't regard AZ imaging to be a second-class activity at all, just a different way of doing it (albeit with some limitations compared to EQ imaging). Ian
  4. Well, the reality is that no forecasts are accurate, they are at best a best estimate, at least for our very variable maritime climate. If you look at the 7-day forecast/multimodel you'll get an idea of just how variable the predictions are between different weather models. And that doesn't take into account the place to place variation either. For example, If anything, I prefer to look at the satellite images real time showing clouds and try to make some judgement as to what is going to happen, but even that often fails! As to whether anything is worse now I don't have any objective data, but it seems worse, at least, this year! Ian
  5. Nice images Helen. What do you use to stack them with? I took several batches in quick succession for the possibility of stacking, but given the featureless face of the Sun I wasn't sure if it would work. Strangely some of the images in your post have a mesh-like background, though individually they seem OK. I guess that this is just a moire effect between the dpi of the image and my laptop screen. I get the same effect on my tablet too. Ian
  6. From the album: The Admiral

    Details as other image but processed to enhance the solar reticulation.

    © iCImaging

  7. Like that. Yes, with the weather forecast to have seen any of it is a bonus. Ian
  8. Tried to see if I could enhance the reticulation of the surface, to 'make it more interesting'! A bit of thin cloud showing on the bottom. Ian
  9. Much awaited, but the weather forecast wasn't particularly good. However, the weather gods played ball in my location and the forecast rain was over by dawn. The sky was in fact fairly clear all morning, which allowed me to set up in good time. Some temporary cloud did roll in for the first contacts, but it was clear-ish for sufficiently long for some imaging. By the time the sky had become quite overcast my imaging widow was at an end anyway, as Mercury's later path was obscured. So here's a rather lack-lustre pic of the transit. Nothing to be seen on the Sun's disk, all very quiet in white light. Ian
  10. From the album: The Admiral

    Fuji X-T1 through an Altair 102mm f/7 Super ED with a TS Photoline 2" 0.79x reducer/flattener. Mounted on a Nexstar 6/8SE Alt-Az mount. 1/1000th sec @ ISO250. Baader ASF100 solar filter. 11th November 2019.

    © iCImaging

  11. I got lucky! The forecast for morning rain didn't materialize, in fact there were relatively few clouds around early on. I managed to get the first half hour or so of the transit before seriously cloudy skies arrived, and the initial contacts were clouded out. It's now out of visibility for me as it's so low in the sky. Still, I've seen it; I shalln't be around for the next one! Ian
  12. I caught the last Mercury transit, but only just as first contact was through plentiful thin cloud, and the clouds were a perpetual problem. Did get some images though. This time, with the Sun being much lower, I'll only get the chance of no more than an hour after it starts, and then the weather will have to cooperate. The forecast looks decidedly iffy. Looks like being cold and windy too. Ian
  13. Welcome Andrei and I'm pleased that you've found the thread useful. You've made an excellent start too, stars nice and tight and a good rendition. There must be a bit more colour lurking in there, it's just a question of finding it . What software are you using to process? Looking forward to seeing more contributions in the future. Ian
  14. I used a (round) LED lighting panel as a flat for my refractor, but it was far too bright. I had to mess around with the electricals to dim it down, but it works fine. You can buy them quite cheaply anyway. This was mine: https://led.me.uk/12w-round-recessed-ultra-slim-ceiling-led-light-lamp-in-cool-white, but of course you could use dimmable ones with the appropriate dimmer. Ian
  15. I guess covering them with electricians tape would also serve (in red of course ;<) ), though not really an engineered solution. I hope you recover well with your 're-engineered' knee. Ian
  16. Huh ha! I just said an incentive, not that I'd actually do it! Ian
  17. My take from this is that as we "approach the terminus of life" (as Clive James so succinctly put it!), we owe it to our family to draw up a list of what we have, preferably with 'advert ready' photos. It would be a nightmare for those without any knowledge of what we do to sort out our gear. I'm trying to heed that thought and have just started to get the list together. I've no doubt that when all our, err, junk, is contained in a list we'd be astonished at what we've amassed. Perhaps it'd be an incentive to de-clutter . Ian
  18. I think covering the lawn with a (permanent) plastic sheet would be worse for your lawn, if I understand you correctly. The rain at least keeps the grass watered, which it wouldn't be under plastic. Also if it does rain before you observe the plastic will be slippery. Can't you make the location into a garden feature with hard landscaping for use during the summer, but easily converted to your needs in winter? Ian
  19. Gradients and colour balance are common in astrophotography, and astro-orientated software is designed to correct that. That's not to say that it can't be done with other software, but it's not in their genes. I understand your problem with the techno-babble associated with the 'art', particularly if you haven't any previous experience with processing conventional photography images, but with use it becomes more familiar. There's an abundance of information on the internet, but it does all take time to trawl through. No-one said it would be a quick process , but have patience, you'll get there in the end. Actually I think what you have is a good start, especially for such a short exposure. When I was doing it I used total exposures up to a couple of hours, all done in 30s chunks! That's a lot of files and it needed a reasonably brisk computer to wade through them all. With 10s subs you will certainly end up with a huge number of subs to process, but it is worth trying to get as much exposure as possible. Worth pointing out that StarTools doesn't stack subs, so DSS can come to the rescue here. I've heard good reports of AstroPixelProcessor (not tried it myself), and which does stack subs as well. More expensive than StarTools, but a totally different workflow, but not in the same league price-wise as PI . SWAG72 of this forum has done some tutorials on it (https://www.swagastro.com/astro-pixel-processor-tutorials.html), but there are others around. Good luck, Ian
  20. I think if you're not careful you can end up spending a lot of money just testing out various software options. Even Photoshop Elements is far from cheap, and PS itself is 'rented' on a subscription basis. PS also does far more than you would need, unless you have an interest in conventional photography as well. StarTools is probably the cheapest dedicated astro processing package, but it may not be to your liking, though the good thing is that it has an unrestricted trial, except it doesn't allow you to save. Pixinsight is quite expensive and from what I understand needs a fair bit of computing power, though it is extremely powerful, and therefore takes a fair bit to become competent with it, especially as the trial is time limited. It's not cheap either. Anyone know if the PS plug-in will work with Affinity Photo? Sorry, not much help, but as happy-kat says, make use of trials. Ian
  21. Well done you! A worthy activity I am sure, this country needs more science and engineering based people. I hope the weather looks kindly on the event, the forecast looks as though there might be some breaks in the clouds. Ian
  22. I have no idea what might have caused it, but surely this wouldn't necessarily be true if the star(s) are bright enough to saturate the sensor? I rather prefer the explanation being a transient movement of the mount. Is it a manually operated barn door tracker? Then again, it's suprising that there is no star streaking, which would mean it would have to move between exposures? Hmm! Ian
  23. Presumably you stacked the RAWs and ended up with a FITS/TIFF from DSS. You need an image in which data has not been thrown away or locked in during the editing process. For that reason you shouldn't re-process JPEGs, particularly as they are only 8-bit and are not lossless, and you need 16 bits as a minimum. I'm not sure about PS, because IIRC the data is frozen in after each processing step. Perhaps a PS user could comment here. RAW processors, like Lightroom for example, always apply the processing steps from the beginning on the RAW file, so if you change the processing, then the result is always a new process on the original RAW. PS may remember the steps, I don't know. Don't get me wrong, I'm not recommending LR for astro processing, but it is useful in tarting up (sorry, polishing) your final image. You could have a look at StarTools (https://www.startools.org/), and although the processing is approached differently to other applications, it is relatively cheap and the trial version is unlimited except that you can' save. If you are used to PS though you might find it too 'cloak and dagger'! Worth a look though. I can't point you to an individual thread, but a search would find plenty. In the the process of subtracting the darks , the noise is combined, so you will end up with a result which contains both the noise of the image and the noise in the dark. So you want to reduce the noise contributed by the darks to a reasonable level (you can easily control that) and the way to do that is to do a lot of them. I typically did around 50 of them, but 20 might be considered OK. Each to his own. The other important issue though is that the background noise is very sensitive to sensor temperature, so unless the darks are taken at the same temperature they may not be representative. This can a big problem with DSLRs where the sensor temperature is not controlled. Not only that but camera manufacturers go to some lengths to subtract noise before committing the RAW to file, so the noise behaviour can't be easily ascertained. Having said all this, with Alt-Az imaging and short exposures, you may not see any difference. I've both used darks, and just replaced the master dark with the master bias. If you have significant sensor unevenness, such as from amp glow, or a large number of hot pixels, you may have to do them however. Yup, discarding subs because of trailing is a problem! Fact of life I think, so you always need to do more than you think . Hope that helps. Ian
  24. Hi, and welcome to the thread. I think they are very good for someone just getting into the 'art', and I agree it just shows what can be achieved with Alt-Az imaging. I was going to say 'with basic equipment', but your Meade is hardly that ;<). Your stars are sharp and round, and there's nice colour in M13, blue to gold, with detail to the core. My only comment is that the sky looks 'very' black, which suggests perhaps you could do with raising the black point a little. That of course might reveal more noise, but more subs will always help there. How many darks did you use? There is some debate about using darks with DSLRs, but if you do, certainly a good number is required otherwise they can introduce more noise. Something to bear in mind. Ian
  25. Super! It looks very much like the ISS to me, one often gets signals when it's over Biscay. On it's approach towards Graves the frequency falls from a high positive shift to high negative shift as it recedes from Graves. You will be observing it during this transition phase. If the ISS is above your horizon then I'd have every reason to believe it is the ISS reflecting from the forward lobes. With Dijon as the focus, Heavens Above gives a better idea of relationships to the track. Note of course that Dijon is BST+1. Ian
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