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mikey2000

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About mikey2000

  • Rank
    Proto Star

Profile Information

  • Interests
    DSLR and mirrorless 'terrestrial' photography, space, telescopes and now astrophotograpy
  • Location
    Leighton Buzzard UK
  1. Taken last summer, I'd really like to point my newer 200PDS at this cluster. This pic was about 20 mins each of R G and B through my 150PDS and ASI1600Mm-c on EQ6-r. it needed heavy cropping to get to this magnification...
  2. Here's one from last summer. I've got a few to upload, now we are entering Processing Season here in the UK This one is 18 mins each of R, G and B plus 12x5mins Ha, processed in PI, shot on ASI1600MM-cool and 150PDS on my EQ6-r
  3. When I saw 68hours, I just had to take a look (I normally only manage 68 minutes...!) A remarkable result with splendid detail in that tiny little core
  4. I hadn't heard of SkySafari - I'll take a look. I've always been happy with Stellarium on my iphone so far. Don't forget the weather apps too! (clearoutside, Scope Nights and Xasteria.)
  5. At these extreme magnifications, this is all somewhat academic. over the last few nights, I managed to gather a bit of data on M51 (that old chestnut!). It's still quite small in the frame but it's 'realistically small' as opposed to 'impossibly small' (like the Grav lens features of that hubble Abell image). I'll get around to is sooner or later but I'll be sure to compare the various drizzle, standard and downsample methods to compare detail/snr etc
  6. OK, I spent a somewhat significant amount of time reprocessing the data today. Now I've got back from seeing Avengers Endgame, I've got time to post the results. Spoiler alert: No gravitational lenses evident in any version. (DOn't worry about Endgame spoilers - I'm saying nothing ? ) Here are 4 extreme close ups. One is from a x2 drizzle integration, one is a x1 'normal' integration. Then I used the PI IntegerRescale (Average mode) to downsample, all processed and NR'd to the best of my ability and put next to the original hubble image (now in mono) Amusingly, the Hubble pic had to be *shrunk* to match even the 4x zoom into the 2x drizzled integration. I can see that the Downsampled version has better SNR but the drizzle version manages to resolve some of the faint fuzzy's shapes a bit better
  7. Interesting thought! I've not been in this game long enough to worry about x2, x3 etc and loss of detail. I've alway just shot full resolution with my ASI1600MM-pro-cool as I read that the binning is in software. If I use the camera in full rez mode then later downsample in post processing, would I still get the same benefit? and if so, when is the best time in the process to downsample (eg, before integration, after stretching etc etc?
  8. Dynamic PSF is a tool that needs a lot of hard work. After reading your post above, I think I worked out how to get the value you want (I used the PI script "FWHMEccentricity") It reports 4.41 pixels for the larger crop area in the original frame. My image scale of 0.78"/pixel therefore gives FWHM of 3.44 arcsecs. (Just out of interest, I checked a few of my other images and they come up with similar numbers)
  9. Thanks for the kind words! If nothing else, I have learned the limitations of a ground based 200mm scope at the edge of a suburban orange zone ? I might add that the subs were taken about an hour after full moon rise ? Maybe I'll try again one a clear night (but maybe I'd rather focus my efforts on a more 'likely' target ho ho) Vlaiv - about the FWHM question .... I'm not sure. Do I have to pick certain size/brightness stars an measure this value or are you interested in the whole-frame average? (I have pixinsight if you can suggest a tool to provide the info you are after.)
  10. I'll post this just for fun and i hope it makes sense. It's a foolish endeavour and feel free to skip to the next topic in the forum... I saw a rather wonderful pic of Abell 2218, showing clear evidence of gravitational lensing. Who wouldn't want to recreate something so spectacular???? Here's a series of pics showing how well I managed with my 200PDS and ASI1600MM-Cool. Before you get too excited, I image at about 0.78" per pixel (and guiding approx 0.5" rms that night) and Hubble is about 0.05" per pixel with presumably perfect seeing and guiding. Here we go, with thanks to Hubble.com: The Hubble shot (full resolution) The full shot from me, showing upcoming crop areas: The inner square is approximately what the hubble took. Lets zoom to the first square, showing the hubble pic overlayed in the right place. Here's the same again but with out the hubble overlay: And finally a the tiny crop of my pic, next to the hubble pic at a similar scale: So, no lenses but I think I found a few faint fuzzies LOL! I don't see any lensing ? (or colour - I took Lum only) The thing is, lots of these hubble pics don't really tell you the image scale. It seems the Abell2218 image must have been a hubble 1:1 crop.... I think I'll look for some larger targets....
  11. Maybe try attaching as JPG instead of .bmp? Still they look good for a quick grab. I got a 200PDS for christmas and it's a bit of a beast - I imagine the 250PDS is quite hard to handle without a crane or forklift etc ?
  12. Not sure how many gears there are but I think the period is 479 seconds. Maybe drop skywatcher a line? ive been using “autopec” built into eqmod. It seems to work well. I forgot two activate it last time out and I saw a small drop in RA RMS (eg. was about 0.6” rms over about an hour). When I reenabled the eqmod PEC, it dropped quite quickly to 0.5” rms and settled there for the next hour) i think the periodic error on this mount is pretty small and smooth, so PHD2 seems to guide it out quite nicely. I’ve not tried the PHD2 autopec RA algorithm yet. My RMS is usually 0.7” overall but gets better when the seeing is good (like the last week or so). I think the PEC contribution is normally smaller than the seeing error.Fwiw, I image at about 0.78”/pixel
  13. The “constellations” reticule is the old version. I believe all new SW mounts have the new circle reticule. May I politely suggest that using a polar scope for alignment is not really precise enough. For visual, fair enough. But for photography, I highly recommend a camera/software solution. Eg, SharpCap. It takes just moments to do and the final adjustments are *tiny* - I don’t even see Polaris moving in the polar scope by this stage.
  14. I think I may need to do this too - I can see the contact marks on the flat bit of the drawtube. My flat bit is definitely a bit on the concave side....
  15. RolandKol - thanks! With your advice, my focuser is back to normal. (I loosened 4,5 a quarter turn then tightened 2 by about a quarter. Retightening 4,5 didn't need much turning. The drawtube doesn't push back in under gravity anymore and the lock seems to work better too. I'm only eyeballing the tube when tightening the lock. Last night/this morning, I could really see it move when tightening the lock. After adjustment, I'm not convinced I can see anything moving ? I use SharpCap Bhatinov mask tool for focusing. It's very sensitive! I've not seen the shift before (I check the graph before and after locking focus...) But then again, I think I've been using stars somewhat near the zenith (eg cappella has been nice and high in the sky recently) so the gravity force isn't acting 'down the tube' and may have minimized the slippage up to this point.....
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