Image Sharpening Courses
LinkedIn Learning Adobe Photoshop Mastery: Color & Tone
CreativeLive Dramatic Black and White Photography in the Digital Age
Udemy Photo Restoration: Color Casts and Fading
LinkedIn Learning Professional Portrait Retouching - Photoshop CC
Skillshare Lightroom CC Tutorials
YouTube How to Edit Photos: Develop Your Editor's Eye
Craftsy Photoshop Sport Image Retouching - Skater Guy
Udemy Image Filtering, Convolution, and Edge Detection
University of Central Florida via YouTube Professional Sharpening Techniques in Photoshop
Envato Tuts+ via YouTube