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The If insurance company HQ at Lysaker, in the dark. You can clearly see that Polypan F doesn't have much in the way of an anti-halation layer: The halo effect is quite evident in this case, not detrimental at all IMO.

Leica M4-2, VC Ultron 28/f1.9, Polypan F @ EI100, Caffenol-C-M 16 minutes @ 20C