The B+W 39mm #590/090 BASIC Red Light MRC Filter is the classic filter for architectural photography. White facades glow brightly, the blue sky is darkened dramatically and clouds become more impressive. It is also excellent for spectacular landscape photographs with greatly improved distant views and for posterization (tonal separation) in photos of objects (blue and green very dark, red light). Its filter factor is approximately 5.

Technical specs:
Filter Type: Black & White Contrast #25 Red
Filter Factor: 5x (2.3-Stop)
Circular Size: 39 mm Filter Thread
Front Accessory Thread / Bayonet: 39 mm
Coatings: Multi-Coating
Filter Material: Glass
Ring Material: Brass
Knurling: Side