Back when single weight fiber papers were much more common, the theory was that an orange-yellow easel could act as a pseudo safelight for any light that was able to penetrate the paper and potentially fog the least dense (shadow) region of the print. Actually, the amount of light reflected back thru the paper is so weak that fogging of mid-tones and highlights is unlikely regardless of easel color.

A worst-case scenario might be a print on thin paper (single weight) having a large zone I black area crossed with small sharply defined zone VI+ areas. (Wire fence in sunlight, in front of coal-black shadows). The stronger light bouncing off of zone I could ...possibly... cause some edge flare into small, finely detailed zone VI+ areas.

Reinhold

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