How do you express warmth in a picture through only color treatment?

There might even be a “warmer/cooler” tool. Failing that, mess with the buttons until it lets you add sort of a reddish/yellowish hue to things.

The warmer cooler tool- turn it to the warmer side. Make sure you play with the saturation after that if you think it is two yellow or orange looking.

diatnce between objects in the pictures?

@Twinkletoes22 Uhmm, I don’t think it’s the literal distance, I guess coldness? :)

I would suggest just using your imagination to visualize what that object would look like hot, and make it look like that. A lot of times, heat causes the object to become more red. The color of a stove burner or a fire depends on the temperature. However, other times this doesn’t work, and makes the object look unrealistic. The book that I am reading doesn’t change color from its heat, so it is unrealistic to change its color.

Often “warmer” in PS is referring to making the picture more vibrate. Sometimes it doesn’t involve adding color but in turn making it more dynamic. Try this next time you’re trying to “warm” a picture up. Open the layer in Lab Color (This is right next to RGB & CYMag settings) then open up Curves. Now before effecting anything, open up the drop down menu and select A. See the line heading diagonally across the grid? Take both corners and bring them across toward the middle of the column, do not go down or up with either corner. Bring both sides in about half way through the grid (the first block of the grid). Do this for both pull down tabs A & B, do not adjust lightness. When you’re done you can change it back to RGB and continue to save back to .jpeg if you like or save for web still works. I made an example just in case you wanted to see what it would look like.

Before
After

See how I didn’t add any color, but it still brought more out? This is what I would consider warming up a picture in terms of using Photoshop.