How to delete a file saved on levels

[Ofnuts]

(07-17-2022, 10:00 AM)Stephen Liu Wrote: Actually I'm not quite clear of the functions of Input and Output levels ?

• Whatever it to the left of the left handle in the Input is converted to the value of the left handle in Output
  
• Whatever it to the right of the right handle in the Input is converted to the value of the right handle in Output
  
• Values between the two left/right handles in Input are stretched/squished to fit between the values of the handle in Output
  
• The middle handle in Input more or less says what value will end up mid-way in the output.
  

For photography, you usually do not touch the output handles because you want your image to have the maximum dynamic range from pure black to pure white.  So you drag the left handle to the right to set the "black point" (value below which everything should be pure black) and the right handle to the left to set the white point (value above which everything should be white). This stretches the available range for other tones in the image.

For instance this picture has no black and no white and could be considered as "flat":

   

I drag the black and white handles to where the histogram really begins

   

In the final image, the darkest pixels are now black and the lightest are white