Quality wise, these negatives seem totally normal. Very durable, no brittleness, staining, streaking, fading or anything. Just the vinegar smell. A thorough washing of the ones I definitely want to save is a good idea. Thanks for everyone's input!

I have a box with a couple of hundred 4 x 5 black & white negatives dating from around 1950 that my dad took (irreplaceable family photos). It smells like vinegar. Is it safe? I assume it's not going to spontaneously combust like old nitrate motion picture stock used to, but is there a danger of some kind of deterioration happening?

I just bought a Nikon D850 and have a Radio Slave 4 from Quantum Instruments and several old strobes from Sunpak: models 622 Super, Auto 611 Thyristor, and Auto 522 Thyristor. Of course Nikon says to use only with Nikon accessories, but does anyone know if any of these are compatible with the D850? I want to use the Radio Slave 4 to fire an array of Norman studio strobes from my Nikon D850.