Mist, photo cropping and relativity

click photo to enlarge
I've been using my relatively small DSLR body (Nikon D5300) and one relatively light and small lens (AF-S Nikkor 18-140mm 1:3.5-5.6G ED) as my walking camera for several months now. I'm relatively happy with the combination's relatively low weight, relatively high quality and relatively wide zoom range. If that makes me sound relatively unenthusiastic, I'm not. Bear in mind that I was raised in Yorkshire, a county where the compliment, "Not bad", is high praise indeed. Seriously, I'm very happy with the results I'm getting: the technical qualities of the sensor, camera controls and lens are very good.

However, the 1.5 crop factor (relative to 35mm) means that the lens' range is 27-210mm and that's not quite wide enough or long enough for me. Better would be 24mm-300mm. However, such a lens would be bigger, heavier, probably not as bright, and probably not as sharp. All equipment involves compromises and my reluctance to carry the Canon 5D2, 24-105mm and 70-300mm (which clearly does cover my desired focal lengths) means that sometimes - maybe 5% of the time - I can't get the shot I want using the Nikon. But, one of the benefits of a good 24 megapixel sensor is the ability to crop the image and simulate a longer focal length, so one of the shortcomings can be addressed.

I took today's photograph with a heavy crop in mind so I ensured the camera was well stabilised. I estimate that I'd have needed a 400mm (equivalent) lens to secure this shot. Yet, cropping has left me with a file that is perfectly usable for most purposes. It shows a view from near Herefordshire Beacon in the Malverns, looking across the low hills around the Severn valley. On our recent walk in that area the mist was clearing when we arrived but started to thicken again as we departed. I liked the colours and gradations in this composition, as well as the detail of the trees and the plumes of smoke. It reminded me of traditional Chinese ink and wash paintings.

photograph and text © Tony Boughen

Camera: Nikon D5300
Mode: Aperture Priority
Focal Length: 140mm (210mm - 35mm equiv.)
F No: f8
Shutter Speed: 1/320 sec
ISO:100
Exposure Compensation: -0.33 EV
Image Stabilisation: On

Megapixels and cropping

click photo to enlarge

How many megapixels does a photographer need? That question is as difficult and as pointless to answer precisely as, "Which is the best camera?" It all depends on your requirements in terms of image size and the type of photography you undertake.

If you sell photographs to print publications it's quite difficult to argue that you need more than 8 megapixels in a suitable camera with a good lens.. Why 8? Well, a 10 inches by 8inches photograph printed at 300dpi requires 7.2 megapixels. If you bear in mind that some magazines print at 240dpi and that most single page magazine images are less than 10X8, then 8 megapixels is clearly enough. (You'll have worked out that 5 megapixels is more than enough at 240dpi.) If, quite understandably, you want to allow for reasonable cropping then 12 megapixels is absolutely fine. If you aspire to cover the odd two page spread then 16 megapixels will do it comfortably. The number of megapixels that manufacturers offer us continues to increase, but as the above shows, unless you have a particular requirement to print large, then 8, 12 or 16 is plenty. Moreover, as print slowly gives way to screens in their many guises those numbers become significantly more generous and allow much heavier cropping.

If it isn't maximum detail in very large size prints that is used to justify high megapixel counts then it's the ability to crop and stillretain a large file. There are purists who scorn cropping, seeing virtue in composing using the camera's frame and sloppiness in composing after exposure by trimming bits off the four sides of the image. I have no qualms about cropping. I see no intrinsic worth in the offered aspect ratios of 3:2, 4:3, 1:1 or 16:9. I do have preferences, and some suit a particular subject - say portraiture - but generally speaking they all have their uses. But to find compositions in the world that perfectly fit these proportions is not always easy and can be an exercise in futility. So I think that cropping has its place.

Today's photograph is one that is double cropped. If I had a tilt-shift lens it would be only single cropped. The Broadway Theatre on Broadway in Peterborough is quite a large building, probably a former 1930s cinema, with a recent, rather good, big, glazed extension on the main elevation. Even standing on the opposite side of the road with my widest lens at 17mm I couldn't photograph it with the correct verticals that I wanted for an architectural interpretation of the building. So, I placed it in the frame with plenty of space around it and took my shot. Then I corrected the verticals and cropped the surround (smaller photo above). However, that composition wasn't as good - I think - as the further crop (main photo above) that gives greater emphasis to the people that I had deliberately included. My second crop changes the character of the photograph from architectural to a bit more of a "street" or "urban" shot, and makes an image that I like better. It's not the way a purist would shoot, but I see no problem with it. The original shot was 21 megapixels: the second crop took it to 15, and the final crop to 9 megapixels.

photograph and text © Tony Boughen

Photo 1
Camera: Canon
Mode: Aperture Priority
Focal Length: 17mm
F No: f8
Shutter Speed: 1/500 sec
ISO: 100
Exposure Compensation:  -0.67 EV
Image Stabilisation: On