The key to producing astronomical images is to scale the image from the the wide range of pixel values in the data into the smaller range of values available on a computer screen. This is called stretching. Stretching brings out faint details by compressing the brightness range. Additionally, FITS Liberator can scales the values to reduce areas that are underexposed or overexposed.
Press Reset. Press Auto scaling. Set the white level to about 6. Set the Stretch function to ArcSinh x. Save the TIFF file. Press reset. There are now 3 files each with the. Each TIFF image will look similar to the image below: Step 3 - Photoshop Creating the final image requires colorizing, leveling, cropping, rotating and removing instrument artifacts. Each of the 3 images will be copied to a Photoshop layer. To do this you need Photoshop and at least basic skills using it. Also before you can start getting data from the Hubble legacy archive you need a program to convert the raw FITS files into workable images.
You can get that here. Some targets are easier than others, some require stitching together many incomplete frames and much more detail work.
Lower wavelengths are redder and higher wavelengths are more blue, green is somewhere in between. We need at least one red, one green and one blue image to make a full color image.
Most of the raw files are just noisy and with huge gaps in them. But not to worry, the data we need is still there. Just start up the program and chose the first FITS file to process. This is the algorithm used to enhance the image, you can try anyone you like, but I prefer the highlighted one ArcSinH x.
Here are some common examples of what you may see while searching the archive:. You will also frequently encounter the word detection in your results, which refers to a stack of all exposures for any given observation, combining all filters into a single FITS file.
Note the WFC3 list in particular is very easy to read and contains an abundance of information all on one page. Oftentimes the information on that page is more than enough for you to know for any given instrument.
One important caveat regarding the filter abbreviations to remember is that for certain infrared observations, the wavelength exceeds nanometers, but only 3 digits are ever used. Ready for more? Read part 2 of the Hubble data tutorial series! Hailing from New York City under some of the most light polluted skies, Judy Schmidt can often be found with her nose in an archive rather than outdoors.
An expert image processor and amateur astronomer, she works almost exclusively with professionally obtained, publicly available data like that of the famous Hubble Space Telescope. With a keen scientific mind and deep regard for the vast, distant, and often invisible cosmos, Judy loves to share the beauty that can be found buried in the treasure troves of public data.
See Judy's work on Flickr or her website. This site uses Akismet to reduce spam. Learn how your comment data is processed. This is a nice introduction to something people might find difficult. I would like to point out that there is data for lots of planetary nebulae in the ESO archive, a resource that I feel has been underutilised.
Also you might like the program CCDStack 2. Just like every website has done since the dawn of any advanced functions like using Javascript, PhotographingSpace. Unfortunately, we must enable this functionality to comply with the EU regulations. Cookie information is stored in your browser and performs functions such as recognising you when you return to our website and helping our team to understand which sections of the website you find most interesting and useful, when NOT to show you popups, and tracking our web traffic, etc.
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The search box lets you look for objects based on their name or coordinates. The advanced search option is useful to restrict the search to specific instruments cameras on Hubble.
Once you have entered your search term and hit the search button, the results will be listed below. Also bear in mind that most observations are only released to the public a year after they have been made, so that scientists get the first chance to work with their data.
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