This nebula’s visual angle (visual size) is several times bigger than the visual angle/size of the full Moon; therefore I had to use the shortest focal length I have available. For DSOs like that, I have a small Newtonian telescope with an aperture of 150 mm and a focal length of 600 mm. The focal length was reduced by the ASA reducer to 438 mm.
Heart nebula is very dim DSO; therefore narrow band is a good option to get some contrast. I collected a lot of data for all 3 channels: Ha, OIII, and SII. The final picture was composed in the Hubble palette. This means OIII goes into blue, Ha into green, and SII into the red channel.
Telescope: | Newton 150/600 mm |
Aperture: | 150 mm |
Focal length: | 438 mm |
Mount | Gemini G53f |
Autoguiding | ZWO 174MM, TS 60/240 mm |
Camera: | Moravian instruments G2 8300M @-30C |
Corrector: | ASA 2″ reducer 0.73 |
Filters: | Baader Ha 7 nm, OIII 8.5 nm SII 8nm |
Exposure: | 17xHa, 21xOIII, 25xSII 600 s bin 1×1, |
Date: | 2015-11-09 |