NGC6826 - Blinking nebula

Authors: Jakob Selbing
Object: NGC6826, Blinking nebula in Cygnus
Exposure: 23 x 60 s(= 23 min), manually guided at 80x magnification.
Equipment: MX5-C through Meade LX200 at f/10.
Image scale: 0.44"/pixel

Comment: This famous planetary nebula in the constellation Cygnus is a bright (magnitude 9.8) and rather small (less than 30 arcseconds) object in the northern hemisphere. As most planetary nebulae it is easily observed even in smaller telescopes. At this particular night seeing was relatively good; after some processing the image had an FWHM of 1.7 arcseconds in X direction and 1.5 arcseconds in Y direction, which is better than most of the other images from Landeryd Observatory.

What might be interpreted by some people as fringing (image processing artefacts) around the central star is in fact true detail in the nebula. It (the nebula) has two shells of gas (actually there is one more shell between the two but its not very clearly defined in this image). The inner shell has a rather sharp edge, which can be seen just outside the central star.

What does a raw, unprocessed image look like?

This is an unprocessed image of the Blinking nebula. 23 images, including this one, made up the processed image at the top of the page. Exposure was 60 seconds, and focal length was 3000 mm. The image scale is 0.67"/pixel in X direction and 0.87"/pixel in Y direction.

As with all CCD imagers the MX5-C delivers monochrome image files even though it is in fact a color CCD imager. The color information is stored within the grid that is caused by the 2x2 color matrix on the surface of the CCD. Color decoding is performed by the camera's software.