M8, the Lagoon Nebula and M20, the Trifid Nebula in Sagittarius rises high in the summer for northern hemisphere observers. The nebulae are surrounded by brown dust near the core of the Milky Way galaxy.
Technical. This image was obtained with a stock Canon EOS 90D DSLR Camera and 500 mm f/4 L IS lens (Newer model: Canon EF 500mm f/4L IS II USM Lens) at f/4 and ISO 1600. Out-of-camera jpeg image with no processing except downsize for web. No dark frame subtraction, no flat fields, no in-camera noise reduction. Daylight white balance. The exposure was tracked on a Losmandy G11 equatorial mount with an autoguider. Mean RMS tracking accuracy was around 0.5 arc-second. Full resolution image is 1.32 arc-seconds/pixel.
This is a natural color image, easily done using daylight white balance. The colors here are as good as a daytime image made with the camera, which are very nice.
Post processing: None, except resize for web presentation.
The Exposure Factors, CEF, CEFA are measures of the relative amounts of light received from a subject. It can be used to fairly compare wildly different lens/telescope apertures and exposure times. For this image:
A higher resolution image, 2000 pixels high, 779 KBytes, is HERE.
Modern DSLRs like the 90D include on sensor dark current suppression and low fixed pattern noise at ISOs around 1600 and higher, making no need for dark frame subtraction.
To learn how to obtain stunning images like this, please visit my Extensive Articles on Photography .
Keywords to this image = astrophoto-1 nebula Messier low-light digital_astro canon_90d
Image ID: m8+m20-500mm-90d-rnclark-c09-04-2021-out-of-camera-1400vws.jpg
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Last updated January 25, 2024