So many people post pictures on Facebook with very advanced cameras, eg from iPhones. Alas, many do not crop their photos, the horizon is not horizontal, there are dark shadows … Some people do not even know the camera can face outwards: I notice so many selfies! I think a gentle article from Jack Schofield on how not to disappoint your friends with holiday pics would be wonderful. Lyndsay (via Facebook)

There are some terrible photos on Facebook, but I think the average level is very high. Back in the dark ages BC (before computers), I edited several photographic magazines and a partwork, You and Your Camera. Then, the quality of the average enprint, as enlarged prints were called, was extremely low, and you couldn’t edit pictures unless you printed them yourself. Photos taken with small-frame film formats – like the 110 cartridges used by Kodak’s Pocket Instamatic cameras, introduced in 1972 – could be dire.

Since then, cheap microchips have transformed amateur photography. Automatic exposure, automatic focusing, face/smile/blink detection and other features have made it much easier to take photos that are technically if not aesthetically superior. Smartphone post-processing techniques based on taking multiple images and/or multiple lenses are now making results even better. There are also possibilities that were barely dreamed of in the film era, such as softening portraits in-camera, making people look slimmer, adding kitten ears, or whatever.

I don’t even mind selfies, because their aims are purely social. They aren’t supposed to be suitable for magazine covers or gallery walls, unless they’re being taken by Cindy Sherman or someone like Kim Kardashian.

I’m willing to cut people a bit of slack on the editing front. If you have a personal computer with a big screen, it’s easy to crop photos and improve them in other ways. You can do some editing in the standard Photos apps in Microsoft’s Windows 10 and Apple’s MacOS, and far more with a free program such as Paint.net, or the paid-for Affinity Photo. It’s harder if you are working on a small screen, and I don’t think Snapseed has an “automated levelling” button to make horizons horizontal. Yet.

The obvious solution would be for Facebook to provide a decent built-in photo editor, and I think that is long overdue. A Facebook help page claims that you can crop photos in Facebook, but I can’t see how…

Make the subject stand out

The key to taking better pictures has little or nothing to do with the camera. It’s about using your eyes, your brain, and usually your feet. It helps if you ask yourself: “What am I photographing, and why?” Once you know the answer, think about how you could better achieve your aim.

It’s unlikely that the place where you happen to be standing is the best viewpoint, unless it has been blessed with one of those signs that says “Take your photo here”. That works for distant views, but most subjects are smaller and closer. Better still, some of them – people, pets, small objects – are movable.

You can move closer to the subject so it takes up more of the frame, change the angle to eliminate confusing background objects, and change position to one where the lighting looks better. If your camera has a zoom lens, you can try using a wide-angle from close up or your longest telephoto setting from a distance. Removing distractions helps your subject to stand out.

It should be easier with people because you can move them to a different position with a better background and/or better lighting. It’s easier to avoid ugly facial shadows than to fix them later.

Of course you have to be clear about what the subject is. Someone standing in front of the Taj Mahal probably does not want a tightly-cropped headshot.

Look at the image

The great thing about using an ancient plate camera – which I did as a photography student in Swansea – is that it doesn’t have a viewfinder. You frame your photo by looking at the upside-down image on a ground glass screen, and throwing a cloak over your head makes it easier to see; it’s not just for theatrical effect. When viewfinders arrived, people started looking at the subject, not the whole frame. That works with telescopes, not with cameras.

Today, most people are looking at screens, rather than through viewfinders. It should, therefore, be easier for them to view the image as a picture, and change things to improve the composition. They should be able to see whether the subject fills the frame, and whether there are poles growing out of people’s heads, or disembodied arms and legs sprouting from the edges of the frame.

At the very least, before you take a picture, look all the way around the edges of the frame to make sure you are not including anything that would be better left out.

Lighting, lighting, lighting

Etymologically speaking, “photography” means drawing with light, and lighting can be the most important element in a picture. Some photographers, including me, love the couple of hours (or the “golden hour”) just before sunset when the light is soft and warm. Quite ordinary subjects can glow in an almost magical fashion, and if you’re on the back of a vaporetto in Venice, it’s almost impossible to take a bad shot.

Bad lighting is the enemy of good photography, which is why professionals have developed techniques to mitigate its effects. These include giant reflectors to bounce soft light into shadow areas, and fill-in flash. I wouldn’t expect smartphone users to go that far, but solutions start with being aware of the problem.

Photographing someone in harsh lighting can lead to hard shadows, so see if you can change your position, or theirs, to avoid them. Light-coloured, preferably white, walls act as natural reflectors. If all else fails, either use a newspaper as a makeshift reflector, or get your subject to face the light.

Lost horizons

I once wrote that “one of the things that separates the amateurs from the pros is that amateur photos often have wonky horizons”. To get a straight horizon, the camera must be level, but that is easier said than done. My Nikon D7500 has a “virtual horizon” that also shows if the camera is pointed up or down, and I still get it wrong more often than you’d imagine.

There are several ways to get straighter horizons. Some cameras, including my Canon G-range compacts, have level indicators that change from red to green when the camera is horizontal. If not, most cameras will show a grid pattern that you can line up with horizontal or vertical lines in the image. If the camera is on a tripod, you can slot a spirit level into the hot shoe, though this isn’t very practical for hand-held photos or smartphone photography. Digital levels are better, but I’ve not heard of any that fit cameras.

One of the problems is that camera levels are not always as accurate as the human eye, which can detect even slight slants, especially when viewing seascapes. This means you have to fix the problem in software. All the Adobe products – Lightroom, Photoshop, Photoshop Elements, Photoshop Express – have ways to fix wonky horizons, but any photo-editor that supports fine degrees of rotation will do the job. The drawback is that you have to crop the picture afterwards.

This is one area where the concentration on post-processing could give smartphone photographers an edge. For example, SKRWT, the Apple iOS/Android app, does a remarkable job of straightening perspectives and making leaning buildings look vertical. This used to be tedious work when using a plate camera with a rising front, and now cheap smartphones can do it in seconds. Don’t say we haven’t made any progress.

Have you got a question? Email it to Ask.Jack@theguardian.com