David: SLTs have back focus "by design" ?

[bfitzgerald]

I had an interesting exchange with Thom Hogan where I basically (via pm) dismissed his comments on AF complaints being mostly "settings/user problems/focus shift" etc etc. I passed on my D90's being out of calibration, yet the message didn't sink in. I'm sticking to my guns on this one something has gone wrong with Nikon at the factory level no question in my mind. All the samples of "problem" D7000's/D800's look very much like poor calibration rather than other excuses.

It's easy to blow things out of proportion as you can find a thread/posts on any DSLR every made (by various makers) and find a complaint/s about the AF. Things do go wobbly at times. But having bought 2x D90's from different countries even, serials are not too close, all official Nikon EU stock, brand new, and both are out AF wise (and by a big margin) I would think that it would be very rare to have 2 iffy bodies. But I can't deny it has happened.

I have no idea with the situation with A mount and the current bodies. I would say that BF appears more common on the complaints I have seen overall (from all makers) but there should be no reason for that other than sloppy QC. BF by design is still not satisfactory. Now one D90 has FF it's no more fun than having BF problems, bar the degree of FF is not as big s the BF was! I'm going to pursue this one until a satisfactory conclusion is found. I bought the second body over 3 weeks ago and it's less than ideal to have to put it straight in for service.

All I can say is I hope for Nikon's sake they calibrate that one properly, body one has to go back again. I have a feeling the phone is going to be getting some action next week in order to resolve this problem. I may get a bit more pro active with this..very disappointing to put it mildly.

[peterottaway]

I had a D90 before I bought the D700 and it was one of the earliest group imported into Australia and it had no AF accuracy problems even with my relatively old Nikon AF lenses. My main causes of complaint were that the AF response was slower than what I wanted and exposure on what I would describe as woodlands landscape was all over the place. General sports, street photography and open field landscape were all acceptable or better.

It may be that as Nikon has pushed the D90 down in price they have lower their quality inspection rate or targets, it may be that the AF unit has been revised / replaced by another with lower standards and you have higher standards than Nikon expect from buyers at this camera level. However given the complaints against the D800 it would seem that somewhere Nikon has slipped up either with the product they are being provided with by suppliers or on their own production lines.

[bfitzgerald]

The worrying point for me is if "some" D800's can hit the shelves and be quite some way off for AF accuracy, then we can't be shocked if bodies cheaper than that have issues too. I believe the fact these bodies are "late production" ones, might be a sign that QC issues were a problem for Nikon. Yes the D90 was not known for a body that had tons of AF issues, some reported but considerably less than the D7000 had. I doubt it's a problem with the modules (they've been around for a while unless the odd iffy one gets in a body)

I'll post a MF and AF shot tomorrow with the second D90, really it's so far off that I was simply lost for words. I very much doubt it had any adjustments for AF at the factory at all, it was that bad!

It is hard to know how many bodies and models have iffy AF, some might not even notice much if they are using a kit lens on the cheaper ones.

[twm47099]

Given Sony is no longer making A200 is a proof it wasn't profitable. No one quits something if it's making a profit for them.

In any case, this "would have" "should have" is a stupid debate. Sony has A37 now as a replacement for A200, and it's a superior camera than a200 anyway.

If they can't make any profit on SLT either (like they didn't on A-mount OVF cameras), they should shut down A-mount and concentrate on something else, like Nex and the camcorders.

Actually, that is a silly statement. In Sony's annual reports from that era, they did state that the alpha part of the camera business was profitable. The compact cameras were the losers. They made a smart move - they introduced the NEX as an upgraded compact camera (make much more money on interchangeable lens camera accessories than on P&S bodies and a case). Later they found that NEX appealed to users other than the traditional high end P&S camera.

[4paul]

Excellent discussion of autofocus mechanics, CDAF vs. PDAF, what it means to use a "system" [body + lens]:

http://www.lensrentals.com/blog/2012/08 ... on-cameras

Many of David's ideas are borne out by Roger's testing, including from the "NEX jpeg settings affect AF?" thread from a few weeks ago.

:Paul