Articles & Tutorials
The Crop Re-evaluated
That doesn’t mean I don’t crop, I do, but normally only along one dimension of the image, almost never in both horizontal and vertical dimensions, well not until recently.
So what has changed?
Why have I seen fit to break my golden rule?
First up I still say, given control over the subject and the time to compose, one should still seek to create images that need only be cropped along one dimension, it stands to reason you will get better ultimate image quality this way and because you have forced yourself to take a little more care at the time of shooting probably a better final composition.
But new technology is a very liberating thing sometimes, and it can free us from the shackels of the past, let me explain.
I am chronologically at that half-century mark and for those of us old enough to remember fondly Kodachrome 25 and Agfa Portriga printing papers we knew that getting good image quality always meant maximising on your film area usage. When we moved into the digital age things actually got worse, those early cameras lacked both resolution and pixels (and no dear reader they are not the same thing) and cameras had high noise levels in spades.
So in short the need to maximise sensor or film real estate was largely related to quality rather than any rigid need for compositional control.
In the interim megapixel counts have gone way up while the ability of the cameras processing to tease detail from the files has also grown tremendously, and somehow despite the screams of disbelieve to the contrary from many internet photo forum lurkers, noise levels have come way down as well, (If you doubt this just check out the difference in noise levels between Canons current crop of compact digicams, the high megapixel ones, ie. the G10 and Ixus 980 simply trounce their older lower megapixel stablemates).
We have now reached the happy point where we have for most purposes resolution to burn; a 10 megapixel DSLR can easily produce great 20 by 30 inch prints, as can any of the high megapixel compacts. Cropping is not the quality killer it once was and of course things will only get better.
When one considers that most of the prints photographers make are actually smaller than 5 by 7 inches, you can see that a bit of cropping is actually not an issue for the great majority of shooters.
So assuming that we should strive for maximum format usage normally, when and why might we break this recommendation and what should we do to make the crop work as well as possible?
First the why.
Often we find ourselves in situations where we are wanting to take candid photos, at weddings, family events and so on, but getting in close puts us in the way and can prevent us from actually seeing the action unfold around us. We need to put a bit of distance between us and the subjects but unfortunately this distance means we may run out of lens reach, or in the case of many compacts find ourselves at the slow end of the telephoto zoom range.
By shooting wider we might gain a very useful stop or more of speed and possibly decrease camera blur by quite a bit, ultimately it might just be the difference between a usable shot and a dud.
Of course you end up beyond the intended reach of the lens, especially when many of the super compacts which have only 3 or 4 times zooms, but if you consider that we could crop say the central 50% out of the frame and still get a good result that shorter zoom range is far less of a limitation.
Going wide can also introduce some issues, most compacts at the widest setting exhibit a bit too much chromatic aberration and softness around the edges, cropping in a bit can remove the offending bits and give a neater looking image.
Flash can also have some impact on cropping, in most instances the built in flash is really only useable up to about 3 metres or so, so shooting from way back at say 6 metres will mean you’re almost sure to get underexposed images or you will need to compromise by raising the ISO to higher levels and putting up with the increased image noise.
If you can stay closer to the subject with the lens set to a “ too wide” focal length there is a greater chance the flash will be sufficient, both because you are within the flash range and secondly the camera will have the wider aperture available that sits at the wide end of the zoom range, this could be as much as 2 stops better on some compacts.
But wait there is more.....shooting wider means that the depth of field is even deeper, so focusing becomes less critical, this means that you can work faster. Many cameras actually allow you to fix the focus, (most compact Canons for example) and doing so with the camera set to the wide end means the cameras’ response is far quicker, which has to be a good thing for “off the hip” candids and street photography.
And speaking of “off the hip candids” one of the aspects with them is the difficulty of pre-empting where the action will take place, often things occur out of frame and are thus missed, but if we shoot wider and crop later we have a better chance of capturing that decisive moment.
Beyond all of the above, I have to accept that many folk do find critical framing and composition difficult when faced with the scene out there in the great outdoors. The expanse of the scene before you perhaps overwhelms the senses, but ultimately for many folk composing on the computer screen is just easier. So once again a wider shot cropped to perfection is probably better than a tighter initial shot badly framed.
As for how to optimise the crop ability, it really comes down to getting the shot as sharp as possible to start with. I know I harp on this one but quite simply most people never get anything like the clarity possible from their cameras regardless of the megapixel count because they introduce too much camera movement into the shot at the time of capture.
Frankly these days noise levels are not much of an issue in any reasonable crop so you can generally ignore this unless of course you are insisting at shooting at high ISOs, and if you are, once again I feel you need to re-evaluate your reasons for doing this.
So there you have it, technology is once again changing the age old approaches to photographic image creation and for many casual shooters this new found “crop ability” has to be a good thing, much as my traditionally based photographers’ brain hates to admit it!