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The Admiral

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  1. Huh ha! I just said an incentive, not that I'd actually do it! Ian
  2. 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
  3. 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
  4. Thanks for the comments. I've already got an R2880 so really this is surplus to my needs and takes up space. Quite happy for someone else to take on the challenge . Ian
  5. We do happy-kat, and I've got rid of stuff on there before, but as this is a bit specialised I thought I'd see what interest there might be here first. That will be the next port of call. In some ways, too good to dump, but it would need someone who'd be prepared to persevere with getting it running again. Ian
  6. I'm clearing out some old photographic gear that I no longer use. In particular I need to find a home for my ancient Epson Stylus Photo R2100 printer, or else it'll end up on the tip. I'm just testing the water to see if there is any interest, as it'll need a bit of fettling. It's heavy and large so it would be collection only, but FREE. It's a 13" pigment ink printer which uses the 7-colour ultrachrome inkset, but has stood idle for a long time. As a result most of the ink channels are blocked, though in the past I've always managed to clear them. I am out of ink on one channel and I'm not prepared to buy another just to see if I can get the print head unblocked. There are ways and means to unblock print heads (with window cleaner! Search the web, e.g. http://www.northlight-images.co.uk/inkjet-printer-cleaning/). When it was working it produced excellent results on matt papers, though I did use ImagePrint v6 RIP software (on win95!) which could be included (you would need to confirm what Windows version it'll work with and whether you could transfer the license. I have the associated dongle). Other than that, I think the mechanics are sound. Alternatively, it might be suitable for conversion to one of the continuous ink feed solutions, such as from Lyson (https://www.specialistinks.com/epson-stylus-photo-2100.php). Please let me know if you have any interest. Ian
  7. 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
  8. 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
  9. 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
  10. 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
  11. 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
  12. 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
  13. 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
  14. Without checking out the detail, I wonder if the ISS comes sufficiently far north even to be able to get rear lobe reflection, unless it is high angle. If you do pick up the ISS the beam switching would be clearly evident. Ian
  15. Congratulations! Looking good so far, be good to see what you get during shower activity. If it is due to reflection of a backfire beam from the Graves antenna, it will be interesting to see if you still see the beam switching. I see no reason why not, but interesting to see nonetheless. Of course, you'd need a nice long duration trail to see that readily, best during shower activity. Ian
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