P:roblem Nikon AF lenses.

Rol_Lei Nut said:

=> Colorfoto Magazine, September 2011.

Or if it isn't online, it doesn't exist according to you?

It's not about "anomalies", but about technological limits and about what gives more consistently accurate results. If your standards are low enough, you might not even notice a difference...

Click to expand...

There's just not sufficient evidence to support this argument. That it's your preference to shoot MF is fine by me. Just don't expect to be taken seriously with "flat earth" assertions that AF cameras, lenses and technology are inherently flawed and produce consistently inferior images.

Ironically, I found the most consistent results with my Nikon AFD lenses, came with the older F90x body which I still have, but even that was not totally foolproof, in low light with open aperture I would use manual focus. However, it was when the news publication I used to work for changed over to digital, some years back that the real problems started. For some reason autofocus on Nikon's digital cameras (and I'm talking about the early D1x, D2x etc.) was always slower to lock on than on the F90x, and in some instances it just "hunted" all over the place. The worst thing was the unpredictability of it all. (and this wasn't the only bugbear with digital by a long way).... Yes you could say the later D3 is better in this respect, but in a climate of drastically falling fees etc., it just doesn't make sense to pour yet more thousands moneywise down the "digital dark hole", just to get something that should have worked properly in the first place.

However, since I quit the news business, the pressure to shoot digital is no longer there and i've returned to film cameras, to manual FM2n's. I find them more reliable as cameras and the manual lenses more solidly engineered. For someone brought up with manual cameras, I have no need of all the automated bits and pieces, particularly when they don't always work as they're supposed to, and the AF lenses are often too flimsy to last the course.

I've had great results with my autofocus lenses, but then again, I only have two: the 28-105 and the 24-50. Both of them focus extremely fast, but they don't have the weight and heft that the manual focus lenses have. I can't really tell a difference in quality between the two...I would be hard-pressed to tell you whether or not a negative came from the newer 24-50 lens set at 50mm on my F100, or my old 50mm f1.4 that stays on my '68 vintage F. I will say that the only lens I've had issues with (and needed repaired) was an old 55 Micro...but I'm also reasonably careful with my equipment, so it tends to last awhile. As far as overall speed is concerned, even a lightning-quick autofocus lens won't work as fast as a hyperfocal setting...and if I'm working with narrow lenses that don't really support a hyperfocal technique, I usually have all the time I need for focusing. Overall, though: no problems with the autofocus lenses...they work well for me.

Here is a reference in English to the Colorfoto article:
www.iffo.nl/temp/index.php/en/lens-tests/202-autofocus-test-objectieven-colorfoto-lens-test.html

The Colorfoto tests are in German. Unless you can read German you're going to have a hard time understanding the methods used in the tests. Rol_Lei Nut reported with specificity their conclusions. Take them for what they are-results of tests. If you can't examine the tests themselves that doesn't make the test results useless. I take them as interesting information, and my not being able to read German does make me dependent on someone else telling me what criteria the conclusions were based on. Without knowing the magazine I am also dependent on someone else telling me if in general their tests are well done. Still, in a test of this sort, results should be straightforward, as they measure things which can be well quantified e.g., "focused/unfocused" and fairly well quantified e.g., "acceptable". Popular Photography magazine has also published tests which showed manual focusing to be superior overall, and showed a surprising degree of inaccuracy in AF. And no, I don't know what issue it was anymore.

My own limited experience with AF is that Nikon is equal to manual focusing in good light and does well in the EV 0 range if I find it an area with good contrast. My experience with Canon has not been so good. It seems like like a "good enough" approach is taken, and have had images which showed inexact focusing even in good light (defining it as no less than open shade on a sunny day). Pressing the button multiple times improved results. I never used a Canon in really dim light so I don't how it does. A problem with either was the tendency of multiple focusing points to mean a lot of hunting or selecting away from the subject. I had a greater problem with the Canon consistently wanting to pick nearer objects, even with the subject centered. This has held true with a 10D I used recently.
This is singular, anecdotal evidence and should be taken as such.

The dinky viewfinders of crop-sensor digitals do make accurate manual focusing harder, compared to 35mm.

lxdude said:

The Colorfoto tests are in German. Unless you can read German you're going to have a hard time understanding the methods used in the tests. Rol_Lei Nut reported with specificity their conclusions. Take them for what they are-results of tests. If you can't examine the tests themselves that doesn't make the test results useless. I take them as interesting information, and my not being able to read German does make me dependent on someone else telling me what criteria the conclusions were based on. Without knowing the magazine I am also dependent on someone else telling me if in general their tests are well done. Still, in a test of this sort, results should be straightforward, as they measure things which can be well quantified i.e., "focused/unfocused" and fairly well quantified i.e., "acceptable". Popular Photography magazine also published tests which showed manual focusing to be superior overall, and showed a surprising degree of inaccuracy in AF. And no, I don't know what issue it was anymore.

My own limited experience with AF is that Nikon is equal to manual focusing in good light and does well in the EV 0 range if I find it an area with good contrast. My experience with Canon has not been so good. It seems like like a "good enough" approach is taken, and have had images which showed inexact focusing even in good light (defined as no less than open shade on a sunny day). Pressing the button multiple times improved results. I never used a Canon in really dim light so I don't how it does. A problem with either was the tendency of multiple focusing points to mean a lot of hunting or selecting away from the subject. I had a greater problem with the Canon consistently wanting to pick nearer objects, even with the subject centered. This has held true with a 10D I used recently.
This is singular, anecdotal evidence and should be taken as such.

The dinky viewfinders of crop-sensor digitals do make accurate manual focusing harder, compared to 35mm.

Here is a reference in English to the Colorfoto article:

www.iffo.nl/temp/index.php/en/lens-tests/202-autofocus-test-objectieven-colorfoto-lens-test.html

Click to expand...

What about top of the line, or even mid-market Nikon body/lens pairings? My objection to his under-documented assertions remains the absence of a large accumulation of negative reviews and anecdotal reports concerning AF inaccuracy linked to bodies or lenses. Too many people have used Canon and Nikon professionally for these problems to go unreported or unremedied if indeed they actually existed.

OFF TOPIC
The unamended version of my post, which CGW quoted, from 3:35 AM remained up after I edited it to the 3:43 AM version, which I again edited slightly a few minutes ago. Bizarre. I just deleted it.

CGW said:

What about top of the line, or even mid-market Nikon body/lens pairings? My objection to his under-documented assertions remains the absence of a large accumulation of negative reviews and anecdotal reports concerning AF inaccuracy linked to bodies or lenses. Too many people have used Canon and Nikon professionally for these problems to go unreported or unremedied if indeed they actually existed.

Click to expand...

Maybe top of the line products do perform better.

Look on photo.net and other places for people talking about problems like front/back focusing or poor focusing. As for anecdotal reports, well, I gave mine; rolleiman and Rol_Lei Nut gave theirs. You'll find many more if you look.
AF has its limits which are well known. Macro, for example. Pros need to produce a product, and it needs to be adequate. They accept that tradeoff. But there are many more amateurs than pros, and many more amateur/prosumer cameras sold than pro-level ones.

I have heard complaints from pros regarding AF failures, though often with the additional statement that they would have missed a lot of shots trying to manually focus, too. For sports they feel they get more keepers, but are less confident that any one shot will be good. The old skill of anticipating and pre-focusing seems to be fading.
Similar is firing a burst to be sure of getting a shot that's adequate, rather than anticipating the peak moment and getting the shot that's perfect.

lxdude said:

Maybe top of the line products do perform better.

Look on photo.net and other places for people talking about problems like front/back focusing or poor focusing. As for anecdotal reports, well, I gave mine; rolleiman and Rol_Lei Nut gave theirs. You'll find many more if you look.
AF has its limits which are well known. Macro, for example. Pros need to produce a product, and it needs to be adequate. They accept that tradeoff. But there are many more amateurs than pros, and many more amateur/prosumer cameras sold than pro-level ones.

I have heard complaints from pros regarding AF failures, though often with the additional statement that they would have missed a lot of shots trying to manually focus, too. For sports they feel they get more keepers, but are less confident that any one shot will be good. The old skill of anticipating and pre-focusing seems to be fading.
Similar is firing a burst to be sure of getting a shot that's adequate, rather than anticipating the peak moment and getting the shot that's perfect.

Click to expand...

Yup. The best is better. Poor technique, simple ineptitude, and reluctance to learn how AF patterns work on an F100, F5, D7000 or D3 get my vote for poor results, not the hardware alone. Pro sports film shooters back in the day relied on burst shooting, too. Why do you think high firing rates were key features on pro film Nikons and Canons? So much for anticipation. AF was a godsend for sports and PJ.

Back focus is user-adjustable on the D7000. Friends have used film and digital Nikon bodies professionally for years with few if any problems attributable to what some here argue is a baked-in deficiency. Sample variation is part of using mass-produced items. But so far I'm not seeing sufficient incidence to suggest a pattern.

I've done my own tests with my body, lens combinations.

It IS true that with all lenses, auto-focusing isn't exact. But, except cases where there were mechanical problems, differences were very small.

For example, with my D200 and Nikkor 70-200 f/2.8VRII. On a tripod with remote release, shooting a test target, I can see the focusing variations at 100% magnifications. But the differences are so small, in more reasonable magnifications such as 16x20, it just doesn't matter. I mentioned this when I sent this lens in for some other thing and the note from tech says "within spec." I have other lenses in this class that perform very similarly.

Another example, (not Nikon) Tokina lens exhibited much bigger variations. Sent it in. Tech replaced the whole optical train and calibrated. Came back performing much better. In fact, there are virtually no variations

Yet another example, Nikkor 50mm f/1.8D. This was an interesting one. Ordered something like 3 to 4 of these and kept the best. Still did pretty badly wide open. Sent it in. Tech replaced the front element (this WAS a brand new lens!) and calibrated. Now it's good.

I also have all-plastic-consumer lenses. Many of them have plastic mounts. I actually have no complaints on focus accuracy or optical performance. Of course, them being not f/1.8 or 2.8, DOF is bigger so focusing errors affect less. Surprisingly, I had no mechanical problems either. They have proven to me they are quite durable despite pretty much everything being plastic. I fully expect these lenses won't last another 10 years, not less 30 years like some old pre-ai lenses. But I didn't pay that much money either. In old days, there were no such thing as consumer grade lenses. (except for E-series). Inflation adjusted, these old lenses were expensive.

Of course, in sub-par lighting conditions, accuracy do suffer. I have experienced this as well. But I wouldn't be able to do that by eyes much better either. Personally, I'm quite satisfied. Results are the same with my three F-100s as well.