Modern Lenses are Fantastic

I thought I'd leave off talking about post processing for a while and air some hobby horse issues on the subject of lenses.

You see it all the time. People post forum messages on dpreview or other such sites, declaring their dissatisfaction with this lens or that lens. They complain primarily about "softness" or perhaps about distortions or maybe about mechanical aspects of the lens like autofocus or how smoothly the zoom ring operates. They rabbit on about lack of manufacturing quality control and how they obviously got a bad example - which they are about to take back to some poor long suffering retailer, for exchange.

The first thing is that few of these people are really qualified to comment on such things. They simply don't have the experience or skill to make the evaluations they presume to. Examining the pictures in question it usually appears that the perceived "softness" has little to do with lens quality. It almost always has much more to do with depth of field and camera shake. The posters complain about edge softness, completely forgetting that objects on the periphery of an image are often much closer than objects in the centre. A lot of the time, they are simply out of focus.

The other thing which is very often true, is that few people know how to hold a camera competently when they shoot. Nor do they seem to "get" the fact that there are certain shutter speeds they should not fall below in field use. I know its old but the traditional hand held rule still applies. At 120mm focal length, use a shutter speed higher than 1/120 sec. At 50mm use a shutter speed higher than 1/50 sec etc.

In lower light, you might well be using "vibration reduction" or "image stabilisation" and you may well be braced against doorways, railings and tree stumps but if you want to make sure you get the shot nice and sharp .... use the rule. It's that simple. In my experience, the difference between the perceived resolution of a (so called) poor lens and a (so called) excellent one is almost always LESS than the actual resolution difference between poor and excellent field technique - believe it.

Lens reviewers make a lot of the need to stop a lens down for best results or they harp about "refraction" softness due to the use of very small apertures. I am certain that resolution charts reveal the shocking truth on a regular basis but I tend not to shoot pictures of resolution charts. Differences in sharpness between f8 or f11 and wide open do not often intrude upon my consciousness with respect to REAL subjects in the REAL world.

Manufacturers of quality cameras and lenses face stiff competition today. They quite literally cannot afford to be marketing sub-standard gear. In fact, in my humble opinion the optical standard of modern lens designs is far and away better than it has ever been. There is no doubt that the quality of modern zooms is good enough for them to effectively replace prime lenses for most people. The lack of speed is more than made up for by the on-going high ISO improvements in image sensors. We used to be thrilled to use f1.8 at a film speed of 64 ISO. In reality, f3.5 at a perfectly acceptable ISO 400 is a good deal faster all up. To be sure, throwing subjects into stark relief against out of focus backgrounds is a little harder ... but we'll manage. Why not use longer focal lengths and try standing back a little?

Yes but what about distortions? ...... It's called the lens distortion routine in Photoshop or Elements. Barrel distortion has always accompanied wide angle lenses. Pincushion distortion has always hounded telephoto. The difference is that today we can push a slider across the screen and straighten everything up. We can also remove chromatic aberration fringes, intrusive vignetting etc In the final analysis, if we really think that an image is too soft we can use some light Unsharp Mask treatment. If the image was fundamentally sound and we don't overdo it, the softness problem goes away.

Then at last there are the moans and groans about how one lens autofocusses faster than another. The plain simple fact is that basic autofocus technique turns almost ANY lens into a "quick one" if we do it right. From day one of the autofocus era I learned to "find an equidistant edge" and immediately recompose. Works everytime and fast - no matter what the lens (well almost) It beats the hell out of 51 active focus points, which in the heat of the moment could be fixating on ANYTHING.

The pixel peepers, macho shooters, forum hawks and resolution chart obsessionists notwithstanding, if your pictures look soft, it almost certainly means it is YOU who fouled up - not the lens.