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Found 7 results

  1. Over the last couple of years, I've been rebuilding my Newtonian into a double truss (reusing the mirrors and focuser from an Orion SPX350, replacing the mirror mounts and building everything else from scratch). I've had some good help from a couple of mates who weld and machine! I’m still some way off completing the commissioning of this – the scope needs shrouds round the trusses to keep out stray light (sewing (argh!) and need to find the right material still), and I need to find myself a suitable micro-PC to mount *on* scope to reduce the mass of cables handing off it – this will tidy everything up very well. But, I had a quick stab on Sat night at trying my CCD on the rebuilt Newtonian for the first time (I have previously used the ZWO cam for lunar work, but this is a bit more demanding...). First off, it does come to focus now - hooray! The test was on M1, the Crab. This is 3x13min using Lum filter self guided with the second CCD in the ST2000XM, taken with an MPCC v1. Focusing went nicely using FocusMax and a quickly built V-curve, but I’d like to also make myself a Bahtinov mask. Image solving gave me the following info: Resolution ........ 0.963 arcsec/px Rotation .......... -4.179 deg Focal ............. 1585.40 mm (350mm dia -> f4.53) Pixel size ........ 7.40 um Field of view ..... 25' 40.4" x 19' 15.3" Image center ...... RA: 05 34 36.691 Dec: +22 00 46.97 I also need to sort out the secondary heater – I thought I may not have too many issues with this, but from subframe examination, it looks as though my secondary started to dew up fairly soon after using it - there was a light misting over it from inspecting. The result is some very odd background issues, see the attached image – all but the first (trailed!) subframe start to show the shadow which I assume is due to the coma corrector… odd that this is off center. Any thoughts? Star shapes look OK. PI gives me 3.3px FWHM, which I think is reasonable given the local seeing: see AberrationInspector output below. There are a few stars bottom right near that massive shadow region that have very long diffraction spikes – may have a bit of cleaning to do there if there’s something on the lens/filter causing extended diffraction. Had to use some judicious background correction in the processing (using DBE twice), and I didn’t use any flats here. Had a little bit of deconvolution and Local Histogram Enhancement. Flats are going to be another challenge and will need the shrouds to do well (definitely required for this camera), but I have an idea on what I may do. Other than that, here it is, warts and all for the pixel peepers… Graeme Processed: Subframe towards end of run - dew on secondary (?) (stretched in PI): Corners, etc at full res from AberrationInspector in PI:
  2. I have been using a 1 1/4 inch UHC filter but this had been causing bad vignetting that was difficult to remove during processing. So, I left out the filter so there was a 'straight 2"' opening into the camera. However, the light pollution meant that 45 s was the maximum exposure. Anyway, I took 65 x 45s of Orion and 165 x 45 s of the Crab - one looks good (for me ) and one looks bad, even for me ! I tried the processing several times but this was the best I could do. So, the advice I am after is, is the poor image of the crab due to the nature of the nebula? my camera is unmodded.
  3. M1 captured 13th March 2016 with 127mm F7.5 APO triplet 0.8x reducer; Skywatcher AZ-EQ6-GT, Atik 314L+ OSC, Sequence Generator Pro, PixInsight. Not sure I've got the focus nailed although it was set using the auto focus routine in SGP. 14 600sec light frames with superbias from 200frames and 50 flats. No darks used (conscious decision following comments on this forum about the need for them). PixInsight Process; Preprocess -> Super Bias from bias frames - Master flat from flats with bias subtracted - Light Frames calibrated, debayered, cosmetic corrected, weighted, registered and integrated. Processing - Dynamic Crop - Dynamic Background Extraction - Colour Calibration - SNCR - MLT Noise Reduction (masked) - Stretched with Masked Stretch - Local Histogram Equalisation (masked) - Curves transformation - MLT Noise Reduction (masked) - ACDNR - Reduce Colour background/contrast with MLT (masked) and Histogram Transformation(masked) - Curves Transformation - Boost Colour in nebula with MLT (masked) and Colour Saturation - Curves Saturation overall - and Curves Saturation to stars only (masked) . Any pointers on steps to improve it or ways to improve my processing welcomed - still wading through tutorials and videos to get my head round PixInsight
  4. Hi All, finally managed to get out under the stars after a long break. Went for M1 as it was in a good position for me and a target that I've never tried properly before. Managed to grab 12 x 10 mins Red, 12 x 10Mins Blue and 8 * 10mins Green. Just some simple processing with PI, Registered, Integrated, Linear fit and a masked stretch. Quick lift with curves and that was it. Hope you like, Cheers John The full frame image And a closer crop of M1
  5. stevebb

    M1 - Crab Nebula

    From the album: Stevebb.com

    M1 Crab nebula taken using a Skywatcher Equinox ED120 on an NEQ6 Pro mount and imaged using Backyard EOS and a modified Canon 450D DSLR.

    © steve@stevebb.com

  6. I got back yesterday from AstroFest and,what do you know, it was clear outside! Just had to go with what was set up at the time: Quattro 8" with Coma Corrector Avalon M-Uno Atik 460EX ZWO OAG (first real time I've used an OAG) with SX Ultrastar Baader 7nm Ha The OAG proved easy enough to use with decent star images, and I wanted to try it quickly on a number of targets. So here we have: M1, 12x5 minutes (oops, forgot to dither) Horsehead and Flame , 4x5 minutes (ditto) Flaming Star, 6x5 minutes, to continue the flame theme (did remember to set up dithering in Nebulosity) ...all with no cropping, so same FOV. Certainly not the greatest of pictures, and only very quick processing, but I hope not too bad for such short exposures in Ha. I'm really starting to think that I prefer just mono or RGB because it all happens so much more quickly (and it went down to -2C last night here... OK, not Pyeongchan, but quite chilly enough.) C&C welcome.
  7. Not posted for a bit, but I did recently capture some half way respectable OIII data for the Crab, which I've here combined with some Ha/S/Lum data from last year - some of it reprocessed. This is with the C9.25 with reducer and Atik 460, which I think gives a nice image scale for this object if you want to see the pulsar properly and a bit of structure (but don't bother at this scale without an off-axis-guider). Colourful Ha(red)/S(green)/O(blue) palette :-). (About 12 hours all in) Tim
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