Legendary Polish neurologist Edward Flatau created one of the first photographic brain atlases way back in 1894. This photo shows how he carefully took 20-minute exposure photos of freshly sliced brains.
The photo is from a recent article published in European Neurology that discusses how Flatau created the atlas and the review it got from a young Sigmund Freud, then early in his career as a neurologist.
To be fair, Freud’s review was 200 words of benign praise and hardly worthy of note, but the article is worth checking out for the discussion and images from the pioneering atlas.
Lucky for us, the article has been made open-access so enjoy it while you can.
Flatau used whole and dissected human brains, unfixed and only rinsed in water. He applied small diaphragms to effect a better depth of field, and took longexposure photographs, with exposure times of 20–30 min for uneven surfaces (ventral, dorsal, lateral and medial facies, plates I, II, V and VII), and up to 10 min for flat sections (horizontal, coronal and sagittal, plates III/ IV, VI and VIII) A schematic color chromolithograph depicted central brain pathways and connections.
Link to article directly.
Link to DOI entry for article in European Neurology.
Mind Hacks 
Sounds awesome but the link might be broken.
The DOI you requested —
10.1159/000322500
— cannot be found in the Handle System.
Really interesting stuff, but the link doesn’t work: “DOI not found”
The DOI is correct according to the journal but it seems it hasn’t be registered yet so I’ve included a direct link to the article on the publisher’s site.
Thanks for letting me know!