For uncooled, magnified, deep sky imaging we used an Askar 71F quadruplet apochromatic astrograph refractor paired with a Player One Mars-C II OSC camera. The scope was fitted with an iOptron iEAF motor focuser and an Altair V2 magnetic 2” filter holder containing an Altair Quadband filter. An SVBONY SV165 guide-scope fitted with a QHY-5II-M guide camera was mounted on the imaging scope. The whole rig was mounted on a Celestron AVX GOTO EQ mount.
The Player One Mars-C II camera pairs excellently with the Askar 71F quadruplet apochromatic refractor.
Because the Mars-C II features a small 1/2.8-inch Sony IMX662 sensor (5.6mm x 3.2mm), it will heavily crop the telescope’s native field of view. This configuration turns the wide-field telescope into a high-magnification setup suitable for small targets.
The Askar 71F has a focal length of F=490 mm and an f ratio of f/6.9
The Player One Mars-C II camera with 2.9µm pixels at 1.22 arcseconds per pixel fits perfectly into the ideal sampling range (0.67"–2.0") for average atmospheric seeing with this telescope.
The field of View (FOV) of 0.66° x 0.37° is ideal for framing small deep-sky objects.
The Askar 71F provides a 44mm flat image circle. Since the Mars-C II sensor uses only the centre of the image circle (6.44mm diagonal), stars are perfectly pinpoint and aberration-free from corner to corner.
The Mars-C II features STARVIS 2 technology with a 54ke- full-well capacity. This allows for long exposures during imaging without clipping star cores. The IMX662 sensor has zero amp-glow.
AstroDMx Capture for Linux x86_64 was used to capture the image data as FITS images with flats and matching darks.
53 x 1 minute exposures of M16 were used. The data were stacked and part processed in PixInsight and further processed in GraXpert, SetiAstroSuitePro and Gimp3.
Screenshot of AstroDMx Capture capturing M16 data
M16 HOO rendering
M16 RGB rendering
The 'pillars of creation' were magnified with this setup providing a good close-up of this feature.
45 x 1 minute exposures on each of M3 and M13 were used. The data were stacked and part processed in PixInsight and further processed in GraXpert and Gimp3.
AstroDMx Capture capturing M3 data
M13
The combination of the Askar 71F quadruplet apochromatic astrograph refractor and the Player One Mars-C II OSC camera proved to be a good combination for imaging small objects.
