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Day 122/365: Exposure Using the Grey Card and Noise Reduction At High ISOs

Just when I started to feel my confidence grow, I take a step back. I have been focusing on spot metering for exposure today. I am really struggling to get to grips with it. This Click It Up a Notch article describes the technique pretty well, but it was this Clickin Moms article that had me hooked. 

So, the idea is that you use the grey card to set custom white balance. Then, with your camera in spot metering mode, you place the centre focal point on the lightest part of the grey card and adjust your settings until the meter is at 0. In theory, you should now have perfect exposure for that lighting. Using the zone system, other colours should give predictable readings on the meter. So average Caucasian skin tone should give a reading of +1.

I played around with this a bit last night and it worked really well. A reading of 0 on the card corresponded to a +1 on my foot, and the picture looked well exposed with a good histogram reading. Taking the zone system to the extremes, you would expect bright whites to take you to +2 and blacks without texture to take you to -2. I am not entirely clear about all the colours in between but I gather it would be useful to know. Some people meter off sky and grass. 

I have been obsessing about this a bit today, so I had to have a little play this evening. I had variable results, and I am not sure why. It worked great until I introduced my kids into the frame. Sigh!

These are all SOOC. 

Here I was practising different colours, trying to get a feel for what colours might be useful for exposure. It got confusing. I gave up. 

f/1.8; 1/125; ISO 800

Perhaps it was the crappy overhead lighting in our kitchen, but I struggled to get good exposure or colour in these pictures. The focus was often off too. We are working towards getting a new kitchen next year. It will be worth the expense and hassle for better pictures alone. 

These look a little dark to me. 

f/2.5; 1/320; ISO 3200

f/2.5; 1/320; ISO 3200

Some of these look a little bright, but to be fair there are very few "blinkies" on them. The white balance seems off even though I set it more than once. Bear got fed up with me holding the card up near to her. 

f/2.8; 1/125; ISO 3200

f/2.8; 1/125; ISO 3200

f/2.8; 1/125; ISO 3200

I am not giving up on this one. I will try again in better lighting. 

I also stumbled across this fantastic Clickin Moms tutorial on reducing noise in high ISO photos. All of my pictures require high ISO at the moment so naturally I was interested in this. She makes the point that "noise hides in the shadows". She recommends over exposing in low light settings because it is easier to bring it back in editing. I need to play around with this idea a little more but I had a mini experiment this evening with an exhausted Roo. 

This was properly exposed using the grey card. 

f/1.8; 1/320; ISO 3200

This was overexposed a bit (but probably not enough) and darked down in editing. 

f/1.8; 1/200; ISO 3200

I think that there might be a difference. I have tried to brighten up a lot of underexposed high ISO pictures and that certainly doesn't work. The noise does indeed live in the shadows. Spooky! This would have been a good experiment for Halloween.