"Nikon's production is all outsourced now, hardly any Made in Japan."
First, there's the xenophobia inherent in such a comment. Some people still seem to think that "made in <Country>" is a good thing, or a bad thing, depending upon how they feel about the country. There was a time when "Made in Japan" wasn't well-regarded in the US. But somewhere along the way that changed, and now there is a new villain.
But the statement isn't actually correct in the first place. Nikon started their Thailand plant camera production back in the film SLR days (N55, N65, N75, N80). I believe 1991 was when the plant first came on line. At times since then, it's been Nikon's primary manufacturing plant, and it was expanded many times to the point where it had capacity to produce millions of units a year.
The one camera Nikon traditionally built in Japan at their Sendai plant since the arrival of the Thailand plant has been the top-end SLR, now DSLR. It appears that Nikon uses this plant to do top-end production only, or to initialize production for a new, complex camera that requires different factory setups.
For instance, the D800 was originally made in Sendai, Japan, as were the original Z6 and Z7. But the derivatives of these models eventually moved production to Thailand. Why this transfer? Well, when you're still designing the machines and process for something entirely new, it's beneficial that the plant is a modest train ride from the engineering HQ. You can observe, correct, and redirect things faster when they're close at hand. But I'm pretty sure that the goal has always been to transfer most work to Thailand.
It appears that there are multiple reasons for Nikon to do this, one of which has to do with costs, and not just employee salaries. It turns out that the Thailand Bhat was useful for exchange rate hedging and balancing for a long time.
For awhile, it looked like Nikon was going to strongly expand production to China, as well. The Nikon 1 series was built in a new plant in China, as well as many Coolpix. Parts production was starting to be sourced out throughout SE Asia. It appears that Nikon has backed off the strategy that was proliferating factories earlier this century. These days, Thailand is the main production facility, Sendai does new model development, and some lenses and parts are still made in China or Japan.
If market contraction continues unabated, it would be likely that Nikon would try consolidating more plants, and some production might very well return to Sendai, Japan. But the Sendai plant isn't really set up to do the volume that Nikon is currently making.
"It is a flawed approach to restrict comparisons to a specific sensor size."
Here's an example of both a normal and a weird statement all rolled into one. The problem with statements like this is that they're usually made by people who want to pivot from something being discussed to something not being discussed.
Two basic attributes are important for most people: price and performance. Price favors smaller sensor sizes, performance favors larger sensor sizes. There is no "perfect" answer, so "flawed" comparisons will continue to be made ad infinitum it seems.
"[A dirty camera lens] can cause dark spots to show up on an image, especially at smaller apertures, that require additional post production. Smudges over important parts of an image can cause unintended softness or blur. Dirty lenses can even cause focus issues for your camera."
That's on the sensationalist side of things (and the second sentence is worded awkwardly).
Don't get me wrong, I'm an advocate for clean lenses. I routinely clean them in the field every evening. But it's not for the reasons stated. My reason for cleaning my lenses is mostly to make sure I don't lose any overall contrast. After all, I bought top-level lenses with high contrast, so why would I put a filter on them or let them get dirty to remove that contrast?
Let's take each of the claims that were made individually:
- Dark spots caused by things on lenses. You'd need a pretty large and obvious thing on the lens for this to be true for most shooting situations (apertures, focal length, focus). If you're using a really wide angle lens at small aperture openings, then yes, sometimes you can see spot-like things in your image. But if this were really a common problem, I'd always see images towards the end of the day with spots compared to ones I took at the beginning of the day—remember, I often shoot in dusty, dirty conditions—and I don't. I sometimes can see a slight contrast reduction caused by dust on the lens.
- Smudges cause blur. Well, they can if they're big and dramatic, but most often what they cause is, you guessed it, a reduction in contrast. Indeed, even a scratch or an abrasion of the coating on a lens tends to mostly cause contrast reduction. You're hard pressed to see a one-to-one correspondence between front element problems and pixels.
- Dirt causes focus issues. Again, it's contrast that's the culprit here. Lower the contrast of information getting to the image sensor and yes, the focus system may start to have issues. On DSLRs, it's much more likely that an unclear mirror or entry to the focus sensor area at the bottom of the mirror box is going to cause real focus issues, though. You haven't been cleaning those things, have you? (Don't do it yourself. Have your camera properly maintained by a repair shop that knows what it's doing once a year.)
Yes, keep your lenses clean, but don't get paranoid about it. It takes some pretty dramatic issue before you have real image/focus problems. So light daily cleaning is fine. A blower bulb, an artist's brush with no coatings, and a LensPen will get you a long, long way. Having some lens cleaning fluid and knowing how to use it will take you to perfection.
