Applying an effect strongly on the right side of an image, lightly on the left

[Starbase1]

Hello All!

I have a old scan of an image, nice details, but the colour is distinctly stronger towards the right hand side than the left, and it appears to change very smoothly.

So, what I want to do is adjust the colour saturation, so that the left edge gets a strong colour boost, with the effect fading left to right, so the right edge is not affected.

Is this possible please?

All clues gratefully received!
Thank You,

Nick

[h_d]

Yup.

Add an HSL Shift adjustment, set the Saturation Shift to the left:

With the HSL Adjustment layer selected, choose the Gradient Tool and drag it across the image:

 

White is full effect, black is no effect.

(I did mine right to left but the principle is the same.)

Cheers,

H

[Starbase1]

Sorry, it took me a while to get the time to come back to this.

 

Wow! So easy I got it right first time, thank you so much!

 

In case it's of interest, I was working on an old map of Mars by Antoniadi, where on side of his map was distinctly darker than the other. I wanted to wrap it around a sphere to make a CGI Mars globe.

I attach the result, showing the seam - it's still visible, but that's mainly because his map edges did not match up quite properly.

Nick