Sholay was originally shot on 70mm film and has undergone various digital restorations over the decades.
When dealing with B-movies from the early 2000s, video quality is usually poor. The films were shot on cheap celluloid or early digital tape formats and distributed on VCDs (Video Compact Discs) or low-quality DVDs.
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High Definition ensures that even older movies look crisp on modern laptops, tablets, and smartphones.