tungsten light backfocusing problem with D7000 + 35mm 1.8G

[Mako2011]

michael2011 wrote:
What I'd like to ask other forum members here:

Q: Is there ANY D7000 + 35mm 1.8G owners out there who do NOT have substantial backfocusing problem under tungsten light? I have seen none so far.

Reilly Diefenb did....you should thank him before requesting more...that's just being polite.

 

[Reilly Diefenbach]

What a bunch of silly comments that's been repeated to death in old threads already and quite an insult to many people including experience users who are having the real issue.

Ah well, just trying to provide some sort of ballast on this forum, I suppose. An excercise in futility?

You'll find very few experienced users on these threads other than those who have had success and are trying to help, like Mako, who has the patience of Job... I won't be on it long either, I've got a couple of dozen perfectly focused images from this morning I'm still working on.

I am under no illusions that anyone who wasn't already so inclined and possessed of a positive mental attitude will take my advice and forget the hobbyist aspirin bottles and go out in the real world and take a few thousand pics until they become proficient. The domain of the test chart is safe and comforting.

It's a bit like the horror of the blank page faced by an author, a fancy camera and tack sharp lens in hand and not idea one in the head as to what to press the shutter button on. A tragedy for our times, really:^)

Anyhow, can you please post the set of four FULL images (daylight and tungsten) I mentioned so we can compare the pictures between different lighting? Preferably the NEF shots of the AF test chart so we can do apple-to-apple comparison and also tell the lighting condition and AF settings? Not trying to argue with you but just trying to get more usable data.

It focuses the same under any light, so no, I've spent too much time on this already. 100% crops under tungsten handheld 35mmG at f1.8 which you claimed were never posted was what you asked for and what you got. And am I really being repititious and silly or is the focus filberts?

 

[michael2011]

michael2011 wrote:
What I'd like to ask other forum members here:

Q: Is there ANY D7000 + 35mm 1.8G owners out there who do NOT have substantial backfocusing problem under tungsten light? I have seen none so far.

Reilly Diefenb did....you should thank him before requesting more...that's just being polite.

You can bet he certainly would gotten more credibility and appreciation from me without all the fanboy remarks about how great the stuff is and how most people are just novice users who don't know what they are doing with the AF test.

 

[Reilly Diefenbach]

I shoot about 40,000 pictures a year, and have been doing so for 12 years, I hope that counts me out of the "new user" camp. And I defiantly have this problem, not only with a cheap consumer lens, but with all my lenses, including a 70-200 VR2, a 16-35 VR and a 24-120 VR. All of my lenses work perfectly on my other cameras in the situations giving the D7000 problems.

Sounds like you know what you're about and should get the camera looked at, because that's not normal by any stretch. All eight of my lenses focus perfectly with the exception of my old 35-70 2.8 Nikkor which needed a small bit of adjustment to hit infinity focus. All the others are untouched.

Now, the problem isn't to get the D7000 to take sharp pictures, I can make it do that in almost any light. The problem is that for the AF to function properly it has to be adjusted for any change in lightning if any component of it is tungsten. Moving from one room to the next requires an adjustment, making the camera very hard to work with in any indoor environment.

And by the way, your examples goes nowhere to "disprove" this issue, if that was their intention. You need to include the same shots, under colder light, preferably daylight with no artificial component, without any change to the AF tune between them and the tungsten light shots.

The man asked for tungsten at f1.8, I gave him to him. The camera focuses fine in any light at all, right down to near total darkness.

Not that I really care, this isn't about proving anything, if you say your camera works fine I am sure it does. But under the same token maybe you should accept that some of us have problems, even when not shooting batteries or test charts.

Well, it seems you really are upset about it as I woud be.

I hope you get things sorted out or maybe try again with a different make and model.

 

[Sante Patate]

My D7000 + 35/1.8 does not "backfocus" under tungsten light at f/1.8; it does not "backfocus" at f/1.8 under daylight with a #23 yellow filter on the lens; it does not "backfocus" under tungsten light with a 3-stop ND filter on the lens.

I use a screen interference method, so I can't post shots. But, to repeat for the thousandth time, knowing it is waste of effort, you cannot use an oblique target, you cannot use one-dark-band targets, and you cannot do it from close: you have to be 30 (better 50) times the focal length away from the target.

It is not that I doubt your observations: I can consistently make my D7000 backfocus by testing it the wrong way, but I have never seen backfocus, and I have never seen a posted example of backfocus, except when it is tested for the wrong way.

 

[michael2011]

What a bunch of silly comments that's been repeated to death in old threads already and quite an insult to many people including experience users who are having the real issue.

Ah well, just trying to provide some sort of ballast on this forum, I suppose. An excercise in futility?

You'll find very few experienced users on these threads other than those who have had success and are trying to help, like Mako, who has the patience of Job... I won't be on it long either, I've got a couple of dozen perfectly focused images from this morning I'm still working on.

I am under no illusions that anyone who wasn't already so inclined and possessed of a positive mental attitude will take my advice and forget the hobbyist aspirin bottles and go out in the real world and take a few thousand pics until they become proficient. The domain of the test chart is safe and comforting.

It's a bit like the horror of the blank page faced by an author, a fancy camera and tack sharp lens in hand and not idea one in the head as to what to press the shutter button on. A tragedy for our times, really:^)

Anyhow, can you please post the set of four FULL images (daylight and tungsten) I mentioned so we can compare the pictures between different lighting? Preferably the NEF shots of the AF test chart so we can do apple-to-apple comparison and also tell the lighting condition and AF settings? Not trying to argue with you but just trying to get more usable data.

It focuses the same under any light, so no, I've spent too much time on this already. 100% crops under tungsten handheld 35mmG at f1.8 which you claimed were never posted was what you asked for and what you got. And am I really being repititious and silly or is the focus filberts?

What I am asking from D7K+35mm-1.8G owners who think they don't have the problem is to do us a favor and provide a set of pictures of AF test chart under different lighting. When used properly (which is not hard to do), the AF chart is a better test than random shots because it keeps things simple and consistent and allows us to better examine the results. If you don't believe it's a good test (at least for the tungsten AF test purprose), that's too bad because I think you are dead wrong. So, here's my request to you and others: if you have a five minutes to spare, take some shots of AF test chart I linked before and post! It's easy!

 

[Reilly Diefenbach]

I plead guilty to being a fan of Nikon equipment, Canon equipment, Fender equipment, Taylor equipment, Dr Z equipment, etc. and long may they run! These are genius electromechanical devices that are works of art in their own way and can be appreciated as such. I've been doing the photo thing with every type and size of camera from Brownie to Calumet 4X5, and never have I felt such a freedom of expression as with the D7000. It's liberating to know that if I do my job, a photo that is tack sharp and just about noise free will result.

 

[Mako2011]

bewing77, there is one poster here who has had the same experience you have had. voudas, He has tested for it under a variety of situations and settings. He's documented it well and is working towards a positive outcome with Nikon. I think, from examining his work, that the problem exist in some bodies. I think the problem is rare and most do not experience it so become a little skeptical due to the small number of false issues in the early days. It seems reasonable that a new AF system might display a failure that's unique to that system. voudas seems a very practical and helpful individual. You might PM him and politely collaborate to the benefit of both. Can't hurt to ask.

 

[jonikon]

What a bunch of silly comments that's been repeated to death in old threads already and quite an insult to many people including experience users who are having the real issue.

Ah well, just trying to provide some sort of ballast on this forum, I suppose. An excercise in futility?

You'll find very few experienced users on these threads other than those who have had success and are trying to help, like Mako, who has the patience of Job... I won't be on it long either, I've got a couple of dozen perfectly focused images from this morning I'm still working on.

I am under no illusions that anyone who wasn't already so inclined and possessed of a positive mental attitude will take my advice and forget the hobbyist aspirin bottles and go out in the real world and take a few thousand pics until they become proficient. The domain of the test chart is safe and comforting.

It's a bit like the horror of the blank page faced by an author, a fancy camera and tack sharp lens in hand and not idea one in the head as to what to press the shutter button on. A tragedy for our times, really:^)

Anyhow, can you please post the set of four FULL images (daylight and tungsten) I mentioned so we can compare the pictures between different lighting? Preferably the NEF shots of the AF test chart so we can do apple-to-apple comparison and also tell the lighting condition and AF settings? Not trying to argue with you but just trying to get more usable data.

It focuses the same under any light, so no, I've spent too much time on this already. 100% crops under tungsten handheld 35mmG at f1.8 which you claimed were never posted was what you asked for and what you got. And am I really being repititious and silly or is the focus filberts?

This is a great shot Reilly! If you don't mind me asking, What kind of flash set-up did you use?
(Nice job with the manual focus, BTW!)
Best regards,
Jon

 

[Mako2011]

Reilly Diefenbach

I think this is my year for a good hummer pic....4.5 months and a wake up before the hunt begins. Would you be so kind as to pass the aperture and shutter speed on this one to me. I'm not to proud to beg

 

[michael2011]

My D7000 + 35/1.8 does not "backfocus" under tungsten light at f/1.8; it does not "backfocus" at f/1.8 under daylight with a #23 yellow filter on the lens; it does not "backfocus" under tungsten light with a 3-stop ND filter on the lens.

I use a screen interference method, so I can't post shots. But, to repeat for the thousandth time, knowing it is waste of effort, you cannot use an oblique target, you cannot use one-dark-band targets, and you cannot do it from close: you have to be 30 (better 50) times the focal length away from the target.

It is not that I doubt your observations: I can consistently make my D7000 backfocus by testing it the wrong way, but I have never seen backfocus, and I have never seen a posted example of backfocus, except when it is tested for the wrong way.

Notwithstanding your "normal" shots being in focus, so you do have backfocusing problem with the chart. Care to explain to me why that's a "wrong way" to take a shot?

Like many others, it's not just the 45 degree chart shots for me. I see it in EVERY shot constructed for easy AF lock. Of course, it's all under tungsten. Once under daylight, the problem is gone in every such shot, same objects.

 

[Mako2011]

If you don't believe it's a good test (at least for the tungsten AF test purprose), that's too bad because I think you are dead wrong.

I've positively showed that test to be inaccurate in a specific case with the light you suggest. How can you be sure your results with the 35mm aren't also inaccurate? If it can happen with the 50mm why not the 35mm. There are procedures/instructions to follow with that chart but I suspect many here won't follow them and ruin your data. Have you done a LV/VF comparison for base line?

 

[Mako2011]

Notwithstanding your "normal" shots being in focus, so you do have backfocusing problem with the chart. Care to explain to me why that's a "wrong way" to take a shot?

Like many others, it's not just the 45 degree chart shots for me. I see it in EVERY shot constructed for easy AF lock. Of course, it's all under tungsten. Once under daylight, the problem is gone in every such shot, same objects.

Could you take a few moments to post the comparison shots, OOC. Should only take a few minutes. you might be experiencing the same problem as bewing77 and voudas. In there case there's a strict light temp point below which the problem occurs.

 

[Reilly Diefenbach]

Thanks, Jon. The setup is a simplified version of one I gleaned from the hummingbird nuts on various websites. Turn down the SB-700 manually until its duration is about the equivalent of a really fast shutter speed. Set up the SB 700 to the left in this instance on a light stand such that it's about a foot or so away from the feeder and off to the left.

Use the handy dandy Commander screen to dial both (manual) flashes up and down by trial and error. The popup flash did fill duties, also turned down pretty far. Shoot CLOSE, out the car or house window with your 70-300VR. I used my AF On, AFC 9 points after a fair amount of experimentation, throwing away at least ten shots for any keepers, which isn't such a bad ratio for these little guys really zip.

Your real hummingbird shooters go so far as to have four or five flashes for perfect illumination, one of which will be pointed at a cardboard sky blue backgroud which otherwise would be blacked out by the underexposed background. Sheesh!

 

[michael2011]

If you don't believe it's a good test (at least for the tungsten AF test purprose), that's too bad because I think you are dead wrong.

I've positively showed that test to be inaccurate in a specific case with the light you suggest. How can you be sure your results with the 35mm aren't also inaccurate? If it can happen with the 50mm why not the 35mm. There are procedures/instructions to follow with that chart but I suspect many here won't follow them and ruin your data. Have you done a LV/VF comparison for base line?

Maybe you were on the edge of color temperature that starts to trigger AF problem and hence inconsistent results from oblique to flat shots, who knows? Maybe it's also dependent on the other factors in the case of 50mm? Just throwing out ideas. I really don't see how you can throw out that sample as anomaly though. Also what I suspect may explain some difference in owners' experience is the difference lighting temperature. I think my light is about 2700K.

I've done dozens of LV/VF tests. Flat angle, oblique angle, doesn't matter. I'm getting the same consistent backfocusing with "real" subjects under the same lighting. I now use LV exclusively under indoor light to workaround the issue.

 

[Reilly Diefenbach]

I'm here to help, Mako, not anything like as much as you, though :^)

I believe it's about f11 at max flash 1/250 at about 200mm with the 70-300VR. See my response to Jon for the dual flash setup which is of course what did the wing freezing thing. The main trick is to get close from concealment with your 300 and fill the frame. I can't get the 500mm!

 

[michael2011]

Notwithstanding your "normal" shots being in focus, so you do have backfocusing problem with the chart. Care to explain to me why that's a "wrong way" to take a shot?

Like many others, it's not just the 45 degree chart shots for me. I see it in EVERY shot constructed for easy AF lock. Of course, it's all under tungsten. Once under daylight, the problem is gone in every such shot, same objects.

Could you take a few moments to post the comparison shots, OOC. Should only take a few minutes. you might be experiencing the same problem as bewing77 and voudas. In there case there's a strict light temp point below which the problem occurs.

Oh I'm pretty sure I'm in the same boat as those guys and many others. As I commented above, my lighting is about 2700K based on the Lightroom reading and my visual observation of WB corrected pictures. I think one reason some people don't see the problem may be their light temperature is not warm (yellow) enough. This is one reason why I requested NEF samples of the AF chart (I should have been more clear.) -- it allows me to measure the lighting temperature for more informative assessment of the data.

 

[Mako2011]

If you don't believe it's a good test (at least for the tungsten AF test purprose), that's too bad because I think you are dead wrong.

I've positively showed that test to be inaccurate in a specific case with the light you suggest. How can you be sure your results with the 35mm aren't also inaccurate? If it can happen with the 50mm why not the 35mm. There are procedures/instructions to follow with that chart but I suspect many here won't follow them and ruin your data. Have you done a LV/VF comparison for base line?

Maybe you were on the edge of color temperature that starts to trigger AF problem and hence inconsistent results from oblique to flat shots, who knows? Maybe it's also dependent on the other factors in the case of 50mm? Just throwing out ideas. I really don't see how you can throw out that sample as anomaly though. Also what I suspect may explain some difference in owners' experience is the difference lighting temperature. I think my light is about 2700K.

According to the manufacture of the buldb...mine was shot at 2650K if that helps. 4ft directly above the target at 60 watts with 2 bulbs.

I've done dozens of LV/VF tests. Flat angle, oblique angle, doesn't matter. I'm getting the same consistent backfocusing with "real" subjects under the same lighting. I now use LV exclusively under indoor light to workaround the issue.

Hmmm...same as voudas but in his case anything below 5000K causes the problem. Not normal as I and many here can confirm. You might follow the advice I gave bewing77. Good luck.

 

[Mako2011]

I'm here to help, Mako, not anything like as much as you, though :^)

I believe it's about f11 at max flash 1/250 at about 200mm with the 70-300VR. See my response to Jon for the dual flash setup which is of course what did the wing freezing thing. The main trick is to get close from concealment with your 300 and fill the frame. I can't get the 500mm!

Thank you! I have my hummers almost tame by the end of the season so I look forward to putting your advice to work....shooting with the 70-200 f2.8 I can get inside the min focus distance, of that lens, to the subject....may try with the 105mm f2.8 as well this year. My inexperience with the lighting has been the problem. Thanks again for the tips on that. Will use SB-600's in command mode as you suggest. ...Happy Hunting!

 

[d3xmeister]

I have said it once in the Olympus forums and I have been laughed at. But seeing all this endless discussions about focus charts I'm gonna say it again.

I had an Olympus E-5 and lots of lenses, from standard grade to super high grade. None of them focused perfectly, but they were not very far off.

So I started calibrating them using focus charts. I used them all. Some of them produced much worse results in real life shooting after calibration. The better one was the ,,screen interference method,, almost perfect but not perfect.

Seeing than I'm doing more wrong than right, I started my own calibration, in real life shooting, that took me about a month. Basically, I go out every day and shot pictures, then adjusting the focus offset by looking at my photos.

After almost a month of shooting, I had a camera and 11 lenses that all focussed perfectly at every setting, in any light, in real life shooting. The results were very poor on the AF test charts, but I was not surprised anymore.

Not all my shooting in that month was for focus adjustment, I just shot my usual photos, observing focus offsets and tweaking accordingly.

That's how I realized that the A4 focus chart shot from close distance and at an angle is the worst method to check or tweak focus, and the ,,screen interference,, method is one of the best. Unfortunately I only found out about this method after my lenses were almost perfectly calibrated.