This month’s challenge is not a big one, since ISO has a limited number of observable effects, however here goes:
For the first part, find a relatively small, portable object to be the subject of your photo. Pop your object somewhere inside near a window so that you get some outside light on it, but not bright sunlight. Switch your camera to Aperture Priority mode with an aperture of around f5.6 and set your ISO to 100 then take your first photo. For each subsequent photo increase your ISO by one stop – it should go 100, 200, 400, 800, 1600, 3200 (it may not go this high), but you may find that your camera is set up to increase in smaller increments. Look up your manual on how to set this in full stops as above if possible.
For the second part, switch things round so that your camera is in Shutter Priority mode, with a shutter speed of around 1/60 – 1/100. Again, starting at 100, increase your ISO with each shot.
If you want an extra bit of challenge, take your camera on a night out to somewhere where you’re hanging out in a relatively dark place. Put your camera into Aperture Priority mode with the maximum aperture your camera will allow – for a basic zoom that’s often in the f3.5 – f5.6 range. Starting at 100, increase the ISO to a value where the shutter speed is fast enough for you to successfully handhold the camera without getting handshake blur.
I look forward to seeing your results in a couple of weeks!