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Day 60: Focal Length

Oh my, things are getting pretty technical around here. Yesterday we had the ISO vs Shutter Speed debate and today it's all about focal length. After a couple of dissatisfying trips to London with my 50mm, I was longing for a wide angle lens. Given that most of my photos are portraits a wide angle lens is just not on the cards. If anything I would go for a 35mm or a 85mm next. I find the choice of lenses, and what they each offer, totally overwhelming. I don't even have a good feel for what the different focal lengths can capture. From my brief research it looks like prime (fixed focal length) lenses are considered to be better than zoom lenses especially when then can achieve wider apertures like f/1.4. 

I figured that playing around with my 18-55mm kit lens would be a great way to get a feel for what you can capture at different focal lengths.  I was lucky enough to visit Trafalgar Square to do this mini project. I took photos at 18mm (wide angle), 35mm and 55mm. 

18mm; f/8; 1/200; ISO 200

35mm; f/8; 1/400; ISO 200

55mm; f/8; 1/320; ISO 200

Firstly, this clearly shows why the 50mm is so useless for landscape photos. It just takes me too close to the subject. I would love to see how close I would get with the 85mm. Alas 55mm is as far as this lens will go. Next time I will use this project to think more about depth of field. I can see a bit of what can be achieved with a 18mm from that first photo, and I like it.

Here is another look. You can see more of the depth of field in this first one. The bright sky was throwing my exposure off - again.

18mm; f/8; 1/500; ISO 400

35mm; f/8; 1/320; ISO 400

50mm; f/8; 1/320; ISO 400

Can I also add a further note on exposure? Last night I watched this great Youtube video on exposure. It pretty much said not to trust the image review on the camera and to use the histogram and "blinkies" to guide you in the direction of good exposure. He gave a lovely example of shooting in snow which gives that blown out background/underexposed subject combo that I have struggled with all summer. I used this approach on the lion with interesting results. Basically the shot was massively overexposed even though the metre was at 0.

The blinkies were going wild on this one.

f/8; 1/160; ISO 400

So, I dialled it down a couple of stops and took this. The blinkies were still unhappy. 

f/8; 1/250; ISO 400

So I dialled it down again until it was at -2 or beyond and I got this one. 

f/8; 1/320; ISO 400

I still had a few blinkies but the lion was starting to look too dark on the screen and I was loosing all faith in digital photography. I'm still not sure if I prefer the second or third image. I am now confused because the take home message from this experience seems to be don't trust the camera image playback... or the meter. I need more of this type of project to figure this out.