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Martin Meredith

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About Martin Meredith

  • Rank
    Sub Dwarf

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  • Gender
  • Interests
    Mountains, cycling, growing stuff
  • Location
    Northern Spain
  1. Pretty Deep Maps v0.2

    Current version is v0.3. I recently moved them from Dropbox so they're now accessible from here. The place to start is the technical guide.
  2. Cloudy, with a touch of Florence

    Nice animation and good to see the reality yet at the same time the impotence of the clouds i this case. What is Florence's magnitude in these shots? Martin
  3. Starlight xpress Ultrastar C

    Welcome to the forum. Have you checked the Lodestar Live User Guide from Don Rudny pinned at the top of this thread? What scope are you using? Martin
  4. A new deep sky atlas

    No, you can't zoom in selectively. These are literally just individual 1-page pdfs with hyperlinks and so are limited to what you would expect to do with a normal pdf document. There is an illusion of something more in e.g. the charts where clicking on a column appears to sort it, but in reality it is just calling up another pdf document.....
  5. A new deep sky atlas

    I'd be interested in any feedback on which pdf viewer works best. There is some discussion from a while back earlier in the thread. For me at least Adobe Reader v 11 works well on the Mac, but Acrobat DC is a pain. Dave in Vermont recommended Sumatra, but I can't test it on the Mac. It is strange that not all viewers are capable of handling local hyperlinks in a pdf document, something that is needed to make the maps remotely useable. Martin
  6. A new deep sky atlas

    Update: Astrojedi has kindly hosted the complete distribution here for the foreseeable future https://www.amazon.com/clouddrive/share/rPeOakPlJbjyMe64hF0TwngYysTiOUi6pFtOE3wVbIC Martin
  7. A new deep sky atlas

    I just checked index.zip and those 2 pdfs are present, so it must be a dropbox/incomplete download issue of some kind. Looks like you've managed to get them now, but do let me know if there are any others that you don't have and I'll attach them to this thread. Martin
  8. A new deep sky atlas

    Just to mention that I got an email from Dropbox saying that on 1st September 2017 they are discontinuing the use of the Public folder mechanism which I've been using to host the Pretty Deep Maps (I guess they consider hosting websites via Dropbox to be some kind of unforeseen usage and hence are killing off the possibility?). Since the distribution is very large it may be some time before I find an alternative host so if anyone wants the charts it is best to download in the next 7 days! I do have a new version planned but since it involves a major rewrite in Python it is still some months away. https://dl.dropboxusercontent.com/u/14005918/index.htm Martin
  9. Collimating- 10” quattro

    I have the 8" version of the same scope and would highly recommend using the Catseye autocollimator. Even so, the main problem is the jerky response of the secondary, so replacing the bolts by some from Bob's Knobs (or similar) is worthwhile, as is adding some simple home-made plastic washers between the tips of the secondary bolts and the secondary holder to smooth out the response. There are threads about this mod, which is often called the milk-bottle washer mod. Martin
  10. EAA first light with new kit

    Try this: I must admit they look like regular (i.e. on the protective window) dust shadows to me. Martin
  11. Washington Double Star Catalogue

    Mick, if you're still looking, try the following 1. Go to Vizier's copy of WDS 2. In the preferences tab (left column) choose 'unlimited' for max 3. On the following line choose something like '|-separated-values' (or any other format you prefer). If your aim is to load these into a spreadsheet, choosing '|-separated' works well. Experiment with different formats. If experimenting, set the 'max' value to something like 50 to prevent downloading the entire WDS each time. 4. I suggest you also click the J2000 box in the preferences table. This adds columns for decimal RA and Dec values to the table which I find to be more useful than the format supplied in the WDS catalogue (you also get that format as the last two columns of the table, so you can use either). 5. In the main table click as many checkboxes as you need (or choose them all and then get rid of them later once you've downloaded). 6. Hit submit and the results will be loaded into your browser window. 7. Check that they are all loaded (can take some minutes on a slow connection). The last line (if you follow step 4 above) should be: 359.97333|-31.20033|23599-3112|TDT4315| |1991|1991|248|248| 0.7| 0.70|11.54|11.90|-3119543 | | |23 59 53.60|-31 12 01.2 8. Copy and paste into a text editor, then delete all the non-data header lines. 9. Import the rest into a spreadsheet or whatever destination tool you have. There may be better ways to do this, but it works for me. This basic approach works for all the 1000s of useful catalogues that you can find at Vizier. cheers Martin
  12. EAA first light with new kit

    Congrats on the new setup! Great results -- the Pelican in particular. Does this mean you're going to pension off your 8" Quattro or will that get a turn on the mount at some point? As a Quattro owner I'd be interested in hearing your opinions on the difference between the two scopes. Having a permanent setup frees you from the constant collimation requirements of the fast reflector... When you say 'processed' images from the night, what processing did you do? cheers Martin
  13. Nice report. Nothing so organised from me but staring northwards at the region just below Cassiopeia I saw 4 in about 8 minutes just outside Bakewell in the Peak District at around 11pm. One was moderately bright but the others were very short-lived and quite faint. All were moving to the 'right' (eastwards). I may have missed some... I got the impression that this year the rate was quite high compared to previous ones I've managed to observe.
  14. Planetary nebula with visible central stars

    In case you want more, here's a list of planetaries organised by the magnitude of the central star. PNcstarMagI.pdf I've never looked at these ordered this way and there are some surprises. The PNs with brightest central stars are not necessarily the best known examples. Martin
  15. Maskelyne at Schiehallion

    It isn't often that my twin obsessions of Munro-bagging and astronomy collide, but they did yesterday at the base of Schiehallion, a 3553 ft Scottish mountain lying to the east of Rannoch Moor. Here I came across the following plaque to the work of Nevil Maskelyne, the Astronomer Royal, who used Newton's theory of gravity to estimate the density of the Earth. He did this by measuring the deflection of a plumb-line caused by the attractive force of Schiehallion. The deflection in turn was estimated by examining the distance of 77 stars from zenith on either side of the mountain, using the same zenith instrument used by Maskelyne during the 1761 transit of Venus. The entire method and the accuracy of the outcome is well-described in this commemorative article. Schiehallion is in some ways an exceptional mountain, standing some distance away from other mountain ranges (cleaner data), being steep on two sides (allowing the instrument to get close to the centre of mass on each side), and being almost symmetrical (easier to estimate its mass). As part of the need to precisely survey the mountain during the experiment, Charles Hutton was the first to use contour lines. On learning this I was rather hoping Charles Hutton was related to the father of geology, the Scot James Hutton, but although they were born within 10 years of each other I don't see any relationship. Here's an earlier shot of Schiehallion from a neighbouring mountain range to the west: In hillwalking terms it is a mountain of two parts, an easy well-made path up the first half through bracken and heather, followed suddenly on achieving the ridge by an extremely rocky landscape calling for stout boots, ending in a surprisingly bijou summit. If you do toil against gravity to reach the top, I can recommend rewarding yourself with a nice pint of Schiehallion IPA in a bar of the same name in the Macdonald Hotel in nearby Kinloch Rannoch! Martin