Moominpapa suggests that my method of randomly selecting a number between one and four hundred, as I have been doing for recent photos from last summer, may not be all that random. He may be right, although I think it will be random enough for these purposes, where it isn't being used very often, and it's completely independent of the photos themselves. It's a pack of cards, so the randomness largely depends upon how well it's been shuffled and reshuffled and where it's cut.
I need to create a three digit figure, between 1 and 400.
So for the first digit, let hearts = zero, clubs = 1, diamonds = 2 and spades = 3
For the second and third digits, let 1 = 1 and so on, with 10 = zero and discounting picture cards.
This doesn't however give an equal chance to each number between 1 and 400; unless one had three packs or reshuffled the whole pack between each selection, it would militate against the last two digits being the same, and the latter two selections might also be influenced by the first if that were not a picture card.
So it may not, technically, be completely random. But it serves my purpose; it rules out the possibility of me exerting any preference, whether consciously or not, and above all, it saves me actually having to make a choice.