Vivitar Flash

I rigged up my ancient Vivitar 2500 flash to the Nikon for this night time walk shot. Even when I bought it to go along with my Minolta X300 it had no facility to do anything clever through the lens by way of metering or quenching of the flash; the term for this back then was camera dedicated flash. Instead it had a crude external Thyristor to quench the flash. Theoretically –for a given film speed- you could select one of two apertures with a switch moved to the red or blue position. The specific aperture was dependent on film speed. ISO 100 gave you F2 or F4 which of course you had to set manually and then flash sync speed could be no faster than 1/60 of a second. If you wanted a smaller aperture then you could set it to max power, get a tape measure out, do the maths based on distance to subject and the flash guide number and then you were away. The guide number is the range at ISO 100 if you had a lens capable of being set at F1. A flash with GN 24 set at F4 was right for a subject 6m away, F2 at 12m and so on. (From the foregoing it should be obvious that a flash will offer no benefit in taking a picture of the moon unless to tastefully lighten the immediate foreground.)
Tonight I could say I adopted an iterative approach to the settings aware that the thyristor could not possibly deal with an open field and a daft dog but in truth I just twiddled the dials madly hoping that something might come out. Also this Nikon is way out of its comfort zone at this ISO so there was more mad twiddling of sliders to try and get rid of some noise.
For all its short comings I would still say this ancient flash is better than the tiny pop up device built in to the top of the camera.