nwadventurer7 wrote:
my goodness this isn't good for those of us that vigorously use our d800's for nature photography, backpacking etc.
OMG, I'd better stop hanging the Chubby w/TC's off my D800 then
50,000 clicks and works like the day I got it...handheld, running around
like a 'monkey with it!!
..it seems that Nikon is perfectly aware of this issue and they fixed it in D810. They just wont admit it to those which frame cracked in D800/D800E. Also given what material it is and how crack looks, I think there might be some material quality issue too.. (as one above me say, bubbles in material)
It is quite possible it is a low frequency failure, but high enough for them to have fixed it as you indicate. It would be interesting to know what percentage of cameras have failed in this manner, and how many of those were not due to abuse, since clearly some failures will be due to abuse. It is also possible they fixed it in the D800 without announcing the fact.
I think we need hindsight to avoid cameras which subsequently have an DX10 version i.e. D600, D800.
LeifG wrote:
It is also possible they fixed it in the D800 without announcing the fact.
Possible but unlikely. The 80-200 AF-D's auto/manual focus switch was built like a carnival toy from day 1 and guaranteed to break if used much. It was never fixed even though it was introduced in the 90's and is still in production.
Ho1972 wrote:
Possible but unlikely. The 80-200 AF-D's auto/manual focus switch was built like a carnival toy from day 1 and guaranteed to break if used much. It was never fixed even though it was introduced in the 90's and is still in production.
As I understand it the 200mm F4 AFD micro AF/M switch was poor, and upgraded on the quiet, though the new one is not ideal. I think the truth is that we do not know.
I need help from FMers and those from other forums to post an assembly drawing for the AF module with respect to the back chassis if you have a copy, in order to further understand and assist Mary and others with left AF issues.
Mary's back focusing deterioration and those with left AF issues might be caused by the shifting of AF module due to stress from the flex circuitry that was connected to it as seen on Armando's photo for the 4 main screws on page 9. One can see the peeling of the flex on the right side of the connector through the large opening of the green PCB, it has a gap of about 2mm compare to the left side? Which is the left side of the picture frame that is having problems.
Nikon has modified the flex circuitry with a smoother less complex and curvy design without something that looks like a S-curve for the D810, that I assume will help to release stress and also prevent putting pressure on the AF module which will affect phase focusing using the view finder.
interestingly hans as you know my left AF issue was resolved on my D800e last year through microadjustments by the tech and i at nikon singapore after hours of taking many test shots. then the firmware update at nikon several weeks later erased those adjustments and we had to start over again with center focus off as well as left focus. subsequent attempts by the tech resolved the center issue, could not get the left focus to meet their standards. this segments of time was between field shooting in both sumatra and sabah borneo, so the camera was not mounted on a tripod and taken off multiple times, hence it seems unrelated to the frame issue? nikon melville fixed it last december after i had used in the field for months....so i am not sure if this information helps, but will be interested in what your assmebly drawings will show...thanks for all your interest here.
As I said the fracture and the focusing issues are 2 separate issues. Unless the fracture have totally broken through then yes, but is not.
But now after analysing and investigating more, I found that the other possible cause must be related to the AF module because using contrast focusing or live view has no issues at all.
hans: Despite my own issues, I'm sure I'm not speaking for myself by thanking you for your interest in all of this and taking the time to try to decipher what is going on. Your expertise is greatly appreciated.
I would certainly try your focus tests if I had it here. If it helps, I almost never use live view, and I know 100% for certain that it happened through the viewfinder and without a tripod; definitely in AF, but I'm not sure if MF improved it or if it got better or worse on a tripod. As I said, it was intermittent and not dependable, which would make me think that any kind of give and take from the fracture could do it? (but again, I'm not an engineer nor do I have any idea if the fracture is even remotely near anything that could cause my AF to act up like that, so I'm taking your word on it)
Interesting you mention "after cleaning sensor": As I said, my issue came and went. It seemed to be better, but then it was definitely back immediately after a sensor cleaning. I was at an NPS event and they cleaned the sensor. While there, my friend wanted to show me the sharpness of one of his lenses, so as soon as the tech finished cleaning, I put my friend's lens on it and snapped a picture and zoomed in really close to see the sharpness, and the focus issue was so evident. A few others tried it, including the NPS rep, and it was unanimous that it had to go to the shop, so I sent it that day.
and for what it's worth, I asked the tech how it looked and if the sensor was dirty and he said no, it was in excellent shape and commented on how clean and well cared for it was. Yet a couple days later, I was told I obviously abused it.
Mary, based on the above diagrams and the fracture you have, I think it is highly possible that your issue is related to the alignment of the reflex mirrors or AF sensor, if the AF module is mounted onto the front chassis and the fracture does not seems to have any direct interaction. But than again intermittent issues are the hardest to tackle and I might be wrong here.
The more I look at the diagrams, the more I believe that the AF module is mounted between the front and back chassis through the opening of the back chassis and with a window frame that locks it down. And then there are 4 spring loaded screws for AF module alignment.
At this moment I can't really tell using my tiny display of my mobile device. Maybe I will give them a better look using my computer tomorrow.
Correction : After looking through it using a computer with a slightly larger view, I found that there are only 2 spring loaded screws used to align the AF module and one spring loaded nut holding it in position preventing the module from getting free during adjustment.
Hans: Re: whether or not the crack has any connection to the focus issues, would you mind humoring me with my lay-person perspective and confusion?
I'm not an engineer by any means, but the way I look at it is... the leg bone's connected to the hip bone.. The geographic area inside a camera is not all that expanse.. and it's hard for me not to imagine there is a connection. Even if it's due to some give and take in movement from the fracture? Maybe from expansion and contraction from hot/cold temperature extremes? Which could explain the intermittent aspect of it?
Mary,
Using your leg and fracture hip bone model, I can understand your concern about the fracture on the hip bone have on the leg that is attached to it, especially during hot and cold weather expansion and contraction. But the case here might be slightly different due the leg is sandwiched between 2 hip bones. The front hip bone that has no fracture and the back hip bone that has the fracture, and the leg is only attached directly to the front hip bone with the back hip bone forming a cage.
Now, let me get back to using technical terms using part descriptions rather than biological terms.
It would have been better if we have another couple of diagrams showing the rear side of the front chassis and the bottom view where the AF module is attached to the front chassis to give us an even better understanding of how the actual construction looks.
With what we have at this moment I can only deduce that there is an AF module frame P/N 1H998-257 mounted to the base on the front chassis by 4 screws. The AF module is then connected to this frame by 2 sets of spring loaded screws which is also use for the calibration of the left and right focus, then there is another spring loaded nut used to fix it into position and preventing the module from falling off while calibration. With this, one can see that the flex that was connected to the module can induce stress due to the module is only being hold in place by the 3 spring loaded screws and nut and not really tighten into position.
Bill,
The above findings might give you a better understanding of how difficult it is to get all 3 focal points set correctly without factory equipment and also give you an understanding of why with a new firmware update can cause your settings to get out of calibration.
The midpoint distant is set at the factory for all cameras to be the same and within a certain tolerance. Once the midpoint is offset due to customized calibration and this could happened if the 2 spring loaded screws are not set at equal counter movement to keep the center focus distant (the fulcrum) the same, then the factory center focus distant has been offset. Now with the new firmware assuming that all cameras still have the same midpoint, that is where the problems comes.
Hope this helps!
My D800 had the left AF problem from new, I'll say that rules out the fracture of the base mount point case as the cause of the that problem
I have the same 70-300 Vr lens, it didn't work well until I did AF tuning , but still it is no match to say the 85mm f1.8G , sometimes it misses the AF as shown in the heron shot, while the 85mm misses focus only because I made a mistake.
When using the 70-300 if it acts up in a shot I'll focus somewhere close and reattempt the shot
What lens was used for the portrait ? the AF point was on the gentleman face ? or did you focus and recompose? was it AF-s of AF-c? both of you were still?
I had similar problems until I went through AF tuning of all my lenses, not the AF is quite precise, except with the 70-300
I'll suggest to follow the AF checklist provided by hans , check with all your lenses, camera on a tripod, focus target fixed on a wall, well lit
