The downgrade of Luminar Technologies by a major analyst firm, along with a substantial decrease in the price target, is likely to negatively impact investor sentiment and the stock's short-term price. Analyst ratings and price targets are closely watched by investors as indicators of a stock's future performance. A downgrade to Underperform suggests that the analyst believes the stock will not perform as well as the overall market, which can lead to a decrease in investor confidence and potentially a drop in the stock price.