Just check it and fix it, it can't be that hard. Can it?

Why can't you just make them better? It sounds like a reasonable question until you start unpacking exactly what it entails. This is exactly what Roger Cicala and company do in the latest LensRentals blog post. As usual with Cicala's posts, the closer he looks, the more complicated the question becomes. So why can't everyone just (repeatably and affordably) make lenses, you know... better?

With his usual critical (and somewhat wry) eye, Cicala looks at the importance and challenges of quality assurance (the processes to ensure you build things to standard) as well as quality control (checking that you've done so). This includes a look at the impacts of design tolerances, manufacturing tolerances, repeatability and the need to make products affordably-enough that people will be willing to buy them. And just what can you do with the ones that aren't quite right?

It's a long article but if you've ever wondered why they don't just check and fix every lens as the last step of the production line, or you've found yourself using the phrase 'you get what you pay for' and you'd like to understand why it's often true, it's well worth a read.

And, if you get a chance to read it all, we'd love to know whether you end up more impressed by Leica's ability to make expensive, mechanically simple, manual focus single-focal-length lenses really well or by the ability of the big brands to build collapsable, image stabilized kit zooms for next-to-nothing and have them work at all. Let us know in the comments.