I wasn’t really planning to post this week – I could not be sure I would have the time. But with the weather outside really miserable (read: basically wet, windy, and featureless) I could spend some time getting acquainted with CS6. And therefore today’s post. Yesterday was altogether a nicer day, and with the days really short (sunset was 15:57) I decided to go for a quick walk up the Hog’s back. The plan was to experiment with longer focal lengths, and give the 75-300mm a decent workout. I have been unhappy with this lens for some time, and will probably upgrade at some point. But since I don’t often use longer focal lengths, I figured that most of the problems were down to user error. So I wanted to do what comes naturally to any scientist: theorize and experiment.
My problem with this lens is the lack of sharpness I generally get; actually, I’m not sure I have even one photo I’m completely happy with at a technical level. There are a few possibilities for this, but once I exclude the less likely (e.g. focusing error, some mechanical defect, etc.) there are really only two that stand out. The lens could simply be soft at the focal lengths and apertures used, or the lack of sharpness is due to movement. The first is entirely possible especially at the lens fully open, since this is a basic and relatively old consumer model (not even IS). I could equally solve most of that by using the lens stopped down to f/8 or f/11. Even cheaper lenses become pretty good at these apertures. The second, I figured, I could solve by using a tripod. However, I think I have underestimated the effect of mechanical vibration and wind at long focal lengths with my smaller tripod. Which is to say I am still unhappy with most of the tripod-mounted images. I’ll need to repeat this experiment with my larger tripod.
As I was ready to pack up, I realised that the setting sun was reflecting off the Shard and other London high-rises in the distance. So I trained the lens in that direction, and started taking pictures. I also had the thought of trying the alternative solution to motion blur: I set the sensitivity to (a rather higher than usual) ISO 1600 and fired a few frames at f/8. I’m rather happy with the result. Of course, at this sensitivity, some noise does creep in. And with the distance involved (the City is about 30 miles in a direct line) there’s a fair bit of atmospheric haze an turbulence to take into account. Still, at the very least this shows that the principal problem seems to be motion blur.
The image above was taken handheld as a single exposure. After some noise reduction, processing involved the usual selective curves to balance brightness and global curves to set contrast.
As always, I encourage you to click on the image for a larger version; comments welcome.