If you need a specific Photoshop feature (layers, masks, adjustments, etc.), I can point you to the best free alternative that supports it. Would that be helpful?
. The Creative Suite (CS) series officially ended with CS6 in 2012, after which Adobe transitioned to the subscription-based Creative Cloud (CC) Key Facts About "Photoshop Portable" free download adobe photoshop cs7 portable link
Tell me so I can suggest the best tool for the job. If you need a specific Photoshop feature (layers,