NGC4565, CCD raw images grabbed during 2 nights : 26 to 27 April (chrominance) and 3 to 4 May (luminance + chrominance) at Lure Mountain, from the Marc Bianchi Observatory dome. C14 SCT with a f/6.3 focal reducer (actually f/6.0 i.e. 2.12 meter focal length), CCD camera SBIG ST-10XME + SBIG CFW-9 color filter wheel fitted with Astrodon L, R, G, B filters + SBIG AO-8 optical autoguiding system. The quadcolor resulting final image totals a 3 hour 56 minute exposure (luma : 28 x 3 minutes, R : 12 x 4 minutes, G and B : 13 x 4 minutes). Because of high altitude clouds in the second part of both nights, the transparency was poor to very poor (1 to 2 magnitudes lost) and the composited chrominance remains noisy despite the great number of exposures through R, G and B filters. The seeing was fairly good, with FWHM of the raw 3 minute luminance images from 2.4" improving to 2.0". The temperature was stable at +12 °C (first night) and +13 °C (second night) inside the dome and the air was rather dry (humidity around 45%).

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