Converting JWST raw FITS images into TIFF images before image process

In a previous post, we have learnt about how to download images of James Webb Space Telescope using MAST portal database. Today let’s learn how to convert FITS images in to TIFF image type using a tool called “FITS Liberator”. 

 

FITS Liberator Graphical User Interface

Note that, this post is for “Pixinsight” users and there is another method to process these images without using “Pixinsight”. The FITS type images cannot be processed using graphics software such as “Adobe Photoshop”. Therefore we need to convert them in to TIFF type images. TIFF images are uncompressed large images without any data lose. Let’s download the FITS Liberator and install. So type fits liberator and click the first link in the search results.

 

 

Searching FITS Liberator in the browser.

After that, click the link “Download FITS Liberator 4”, as shown in the figure below. Then you will direct in to another page which contains all the download links for any required operating system you need. Click on the required link to download the required setup file.

 

 

FITS Liberator Website [Link]

 

Download page

 

Download links

Then double click on the setup file that you have downloaded and run the setup and install to your computer.

 

Installing FITS Liberator

Before open the FITS Liberator first you need to select all the required FITS files from your downloaded files. Following are the downloaded folders that contain the FITS files and other unwanted files (I have mentioned as unwanted because we do not need other file to do the image process. Other files may need for scientific research).

 

 

Folder which contains the FITS files and other unwanted files

Open one folder and you can see several files inside it. From these files you will need only one file. That is “i2d” FITS file. Then copy and paste all the “i2d” FITS files in to another folder from each folder that you have downloaded.

 

 

“i2d” FITS file inside every folder

 

 

All FITS files copy and pasted in to another folder

 

Then open the FITS Liberator software and open one FITS file at a time. 

 

FITS Liberator Graphical User Interface

 

In here, I have opened a FITS file and then click on “Asinh” in the Scaling tab.

 

 

Open a FITS file.

 

 

Clicking on the “Asinh” in the scaling tab

Then you have to adjust the Black level and White level accordingly to avoid clipping of Black levels or White levels. Then select “Bit depth” as 16-bit and save the file as TIFF file format.

 

 

Adjusting the Black/White levels and save the file in 16-bit TIFF format.

 

Do these above mentioned process for each FITS file and save the files as 16-bit TIFF files in another folder. As you can see in the image below, the saved TIFF files have different dimensions. Therefore you need to do star aligning and stacking process these images using “Pixinsight” software. The only problem is the “Pixinsight” is not free. After stacking and star aligning the files, then you can use “Adobe Photoshop” to image process and get the outcome as you needed.

 

Saved TIFF files

In the next post I will guide you how to process these images without using “Pixinsight” software. We will use “Siril” to make star aligned registered FITS files. And I am going to use “FITS Liberator”  for converting process from FITS in to TIFF images.