He also used very small apertures and consequently very long exposures, at least on the still lifes. Also mentioned in the daybooks, as I recall, the vegetables and shells were exposed for a few hours in some cases, for example.
Modern photographers tend to avoid apertures like f/64 because of sharpness loss from diffraction, but the trade-off is less depth of field. I don't think anyone will complain that his aperture was possibly too small for optimum sharpness on Pepper 30.
Another good read, having to do with Edward, is Through Another Lens, by Charis Wilson, who is the lady he met in the timeframe where the published portion of the Daybooks end.