Astrophotography tips
N0.1 (Quality: RAW vs JPEG)
Astrophotography Camera Settings - As you are probably aware, most DSLR cameras include the file format in which images are stored and are set to JPEG as the default. Most 'high-end' consumer digital cameras also allow images to be saved in a proprietary 'RAW' file format, which allows for higher-quality images (especially during the post-processing stage). A RAW file format preserves all of the original data as it is read from the camera's sensor. This is without a doubt the best file format for shooting Astrophotography in, making it the best Astrophotography camera setting to use. The RAW file format saves data with a high bit depth (typically 12 bits) that is output as linear data from an analog-digital converter. This is critical for astronomical imagery! High-bit linear data provides the most flexibility in terms of how the data is calibrated, manipulated, and enhanced to produce the best images possible. That being said, if you don't want to go through the trouble of calibrating your camera and just want a quick image to show, you can shoot JPEG formatted files on your camera. The camera will convert the linear file into a recognizable photograph, which you can then edit in an image editing program to adjust the contrast and color balance. In fact, some new low-noise DSLR cameras are so good that you can shoot a single 3-minute exposure in JPEG format with brighter objects like M17 and still get a good picture! Isn't that amazing? This may be the approach you want to take if you are a beginner. In fact, we would recommend it! To get started, shoot in JPEGs and learn your way around the scope, camera, and the subject of Astrophotography in general. Then, as you progress to the next level, you'll want to begin shooting in RAW file format.
Camera Settings for Astrophotography
Most cameras also offer a selection of image resolutions. These options can be referred to by various names, but the most common are 'Large,' 'Medium,' and 'Small,' or 'High,' 'Medium,' and 'Low.' This option allows you to choose between the highest, true optical resolution from the sensor and a lower resolution created by in-camera interpolation. Always select the highest resolution and quality setting. The Canon 20Da, for example, has true optical resolution of 3504 x 2336 pixels in addition to lower resolution options of 2544 x 1696 and 1728 x 1152. However, the in-camera settings for contrast, saturation, color balance, and sharpening are not applied to RAW files. The RAW file retains all of the original data as it is read from the camera's sensor. Some cameras provide in-camera compression for RAW file formats that differs from the compression used for JPEG files. This type of RAW compression does not waste data. Astrophotography Camera Settings (JPEG) - DSLR cameras have different JPEG compression settings, which are sometimes referred to as 'quality' settings. Higher quality implies less compression, resulting in a larger file size. For normal daytime snapshot photography, some people shoot with a lower quality setting that compresses the JPEG files together, which, of course, takes up less space on your device. The disadvantage of using the JPEG file format is that you will lose information because that is how it achieves such high compression ratios, by throwing information away.
Astrophotography Camera Preferences
Astrophotography Camera Preferences (RAW & JPEG) - You should try this if you have a camera that allows you to shoot in both RAW and JPEG formats at the same time. This is possible with the 20Da. That way, the camera applies whatever in-camera contrast and sharpening settings you have to the JEPG only, giving you a quick preview of what the image looks like without having to process the RAW file. So, that concludes Part 1 of this article, but if you want to hear more from us, you can always visit our previous blog posts by clicking here.
