i was at a meeting of the folks who do photography for the NFS in Mpls.
one of the things that came up was that in taking photos from the same place several time a month problems came up in keeping the photo looking the same.with my film cameras every shot was the same unless i changed film.with my new digital i was tempted to flip between photo styles in the big menu.from landscape to food,to soft skin to sports,you get the idea.the food setting gave some nice deep colors for example.
this was a phenology project and some folks did great work showing the season changing at places like Minnehaha falls.with my playing around in the camera menu i had to search around when picking out my shots to send in.next time i do something like that i'll set a chip aside and load it in for whatever project i'm on and not touch the settings.
that way i'll have all the shots in one place and in order.
same with the BW shots.i have photos of my buddy sitting next to me and every bit of fluff on his hoodie stands out.i must of done a "what if" on some landscape shots and the detail is nothing like that because i flipped around the menu and took them on "sports" or "food".

that all makes perfect sense.

I was thinking about all you said and think I will also carry my pocket camera along. seems I'm trying to take shots of things that move so I get frustrated trying to adjust settings quickly enough.

for your project of taking a photo of the same thing each month, it would make sense to just use the same sd card.