It's been a bit of a strange day.
First, I find a hat full of money. Then, I'm chased by an angry guy with a guitar!
When I got home, my wife yelled from upstairs, "Do you ever get a shooting pain across your body, like someone's got a voodoo doll of you and they're stabbing it?"
I replied "No..."
After a few seconds, she asked, "How about now?"
This week, I think it's handy for beginners to note that cameras by default try to replicate a scene to the level of an imaginary 18% grey tone, and there are all sorts of implications. There are settings that try to second guess what you're doing, and might pay more attention to the central zone than the edges. The camera doesn't really know what you want your picture to look like, even if you do.
Very difficult situations for the algorithms are, say, a subject backlit against a bright sky or a yellow flower against dark foliage. The algorithm may get this wrong by three stops or more, and now there's a silhouette of the person, or the flower's petals are blown to the point of no details remaining.
For this situation, we should either go completely manual exposure (chimping in an iterative process to get the correct setting - do check the faces - but being aware that in many music shows the lighting changes from minute to minute) or choose from what is typically in Pentax called the AE Metering menu its Spot Metering option, and point at the subject. Wedding photographers use this mode to make sure the dress is exposed correctly, as it's notoriously the brightest object in scene, and yet, it's important to see all its texture.
At the gig I noticed there was a cycle of coloured and 'white' lighting going on, and waited for the white phase to snap this picture of Larry Graham, the great bass player from Sly and the Family Stone, and a confidante and mentor to Prince. It still ended up at ISO 6400 and this was with a humble K-30 but Pentax sensors and the DA*50-135 are very good. We can clearly see the sweat making Larry's shirt stick to his chest.
Concert photography often sacrifices shutter speed (and hence sharpness) and ISO (hence graininess) so the images are always compromised versus the perfection of a studio environment with flashes and strobes.
It can get to the point where the colours are so distractingly bad (high ISO not only adds noise, it destroys dynamic range of colour tones, Internet 'experts' often forget this) a black and white conversion is necessary.
To finish with, there's the story of the three men sitting in a room smoking a few joints who run out of gear. One stands up and says, 'Look, we've got loads more tobacco, I'll just nip into the kitchen and make one of my speciality spliffs.'
Off he goes into the kitchen where he tips out some containers from the spice rack, grinds them up and rolls them up. On his return he hands it to one of his smoking partners who lights it and takes a long drag. Within seconds he passes out. Ten minutes go by and he's still out cold, so they decide to take him to hospital.
On arrival he is wheeled into intensive care. The doctor returns to his friends and asks,’ So what was he doing then? Cannabis?'
'Well sort of', replies one of the guys, 'But we ran out of gear, so I made a home-made spliff.'
'Oh' replies the doctor, 'so what did you put in it?'
'Um, a bit of cumin, some turmeric and a couple of other spices.'
The doctor sighs, 'Well that explains it.'
'Why, what's wrong with him?' demands one of the men.
The doctor replies, 'He's in a korma’.
The rest of the series here:
Clackers' Beginners Tips (Collected) - PentaxForums.com