1. Material: Cardboard2. Weight: About 500 grams3. Dimensions: 29 x 42 cm4. Thickness: About 0.36 cm5. Without hand support, can stand independently and save time and effort6. The angle can be adjusted at will, more portable7. Silver side: Dark side fills in light, brightens the shadow part, compared with white, the intensity of reflection is greater8. Black surface: Used to edge or weaken the dark surface light, deepen the backlight surface, and increase the picture contrast9. White surface: Dark surface fills in light, brightens the shadow part so that the object receives the light evenly, softer than the silver surface

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