posted on Dec, 31 2013 @ 10:25 PM
reply to post by alfa1
So you are saying this photo is the outer space equivalent to a model being photoshopped skinnier.
That's a good analogy.
Several years ago, before the Babb/BAUT/Cosmoquest forum turned fascist, I posted a little experiment to illustrate how jpg compression artifacts
1. From the "Start" menu on your computer, open up Programs>Accessories>Paint.
2. Set your image attributes to 2 x 2 inches.
3. Select the "Draw Line" option and select the broadest width.
4. Select "Draw Ellipse" and draw a circle:
5. Save this as a .bmp file (circle1.bmp).
6. Now click on the bucket fill icon and select the red color.
7. Click on the inside & outside of the circle to fill it in:
That looks nice & neat.
8. Save this as circle2.bmp
9. Open the circle1.bmp file again.
10. Save it as a jpeg file (circle1.jpg):
11. Click on the bucket fill icon and select the red color again.
12. Click on the inside & outside of the circle to fill it in:
Whoa! Yuck, what happened? When you saved it as a jpeg, it compressed the bits around the circle. If you check the size of the files you saved,
you'll find the .bmp files are ~104kb, whereas the .jpg files are ~4kb.
The moral of the story is that jpegs are great for storing & transmitting images efficiently, but are not good for any sort of high-resolution
Hope this helps.