People who upload images in blogger post always have a ash colour border or shadow around the images. Many don't like to have that border around images.
In the above picture you can observe image with border and an image without border. So in order to have an image without border you just need to tweak a little bit of CSS code. Below is how you do it.
1st Procedure
Step 1: Log in to your blogger Dashboard.
Step 2: Click on Template
Step 3: Next click Edit Html and click Proceed
Step 4: Search for ]]></b:skin>
Step 5: Add the below code just above it.
img{ box-shadow: none !important;padding: 0px !important;border: 0px !important;}Hope this solves your issue you can also go to template designer and add the above code in the Add Css link.