Dear all,
I had this problem and solved it, later on I found much discussion on that on the net so I wrote that on a Gen. Photo list (and also on my site), but it might be useful for some guys/girls here...
Sorry for the kinda off-topic, but since it also affected my Super-Macro shots, I thought of posting it here.
"Nikon D300 front focus problem
Yes I had it. And looking on the internet I found a LOT of people with the same problem. I will try to make my story short:
I sold my ex-D80 with my 50mm/1.8D lens that I used to take portraits (mainly of my son), bought a new D300 and started to review my lens quiver (the review is still going...
)
When I got a new AF-S 50mm/1.4G lens it was like I forgot how to shoot!!! 90% of my pictures at f/1.4 were out of focus, with the critical focus falling short of the intended place. I would focus on his eye, and it would fall on his nose, ear or shoulder!!!
Looking closer into it I notice another good amount of front focus (but not as bad as in the 50mm, unless at the 70-200mm over more than 25m at f/2.8) specially in my f/2.8 lenses at maximum aperture (70-200mm/2.8VR, 14-24mm/2.8 and 105mm/2.8D doing macro at 1:1), I guessed that the problem was happening in ALL lenses, but I suspect on the darker/slower zoom lenses the DoF simply was too wide to show it.
Talking to an Official Nikon Engineer on a Photo Fair I got the following info:
1)AF Fine Tune was designed for a "Lens with AF problems", and not for a camera with focus problems, and it is very rare for one photographer to get 2 lenses with this problem;
2)Lenses are easy to check for AF problems and at the equipment they had at the fair he checked my lenses OK, anyone probably can check that at any Nikon service center quickly.
3)If your problem is in your camera body it is derived by only one thing:
The CMOS Sensor is not properly aligned, or at the right distance, relative to the lens mount and/or Focus sensor(image) which sits in the lower part of the camera, under the mirror. This can happen naturally, by manufacturing defect or due to camera fall as well as other reasons... I would guess transport, wide ranged temperature variations, even some small detail in the production line.
That problem can have a few levels of severity:
1)Small misalignment that can be fixed by software, available at the service center only, without "opening" the camera;
2)Small misalignment that can be fixed by repositioning of the sensor, that requires "opening" of the camera (if you "open" it you might revoke the warranty depending on where you are!!!).
3)Heavy misalignment caused by a misalignment of the frontal and back parts of the camera body, which will require camera replacement.
Any Nikon service center can "check" what is the severity of the problem without opening it.
I sent mine for this check and got good news, mine was very light (my AF-S 50mm/1.4G required 7-10 points in AF Fine Tune portrait distances) and was corrected by software. Lucky me!!! It is perfect now up close and far away focus are OK!!!
The software correction is no biggie, well it is not very high-tech really, it's just Phase Sync adjustments of the AF Sensor as it's phase is not matching the Image Sensor position.
I suspect that the physical limits to this software correction is due to the size of the AF Sensor, if the Phase falls out of it, it would require manual reposition or replacement if not possible.
This has been done by every electronic technician (maybe not by software then) since well before I was born in the 70s!!! (giving up my age
)
It is just a thing that we don't have in our (already too complicated) camera menus...
I had this problem and solved it, later on I found much discussion on that on the net so I wrote that on a Gen. Photo list (and also on my site), but it might be useful for some guys/girls here...
Sorry for the kinda off-topic, but since it also affected my Super-Macro shots, I thought of posting it here.
"Nikon D300 front focus problem
Yes I had it. And looking on the internet I found a LOT of people with the same problem. I will try to make my story short:
I sold my ex-D80 with my 50mm/1.8D lens that I used to take portraits (mainly of my son), bought a new D300 and started to review my lens quiver (the review is still going...
)When I got a new AF-S 50mm/1.4G lens it was like I forgot how to shoot!!! 90% of my pictures at f/1.4 were out of focus, with the critical focus falling short of the intended place. I would focus on his eye, and it would fall on his nose, ear or shoulder!!!
Looking closer into it I notice another good amount of front focus (but not as bad as in the 50mm, unless at the 70-200mm over more than 25m at f/2.8) specially in my f/2.8 lenses at maximum aperture (70-200mm/2.8VR, 14-24mm/2.8 and 105mm/2.8D doing macro at 1:1), I guessed that the problem was happening in ALL lenses, but I suspect on the darker/slower zoom lenses the DoF simply was too wide to show it.
Talking to an Official Nikon Engineer on a Photo Fair I got the following info:
1)AF Fine Tune was designed for a "Lens with AF problems", and not for a camera with focus problems, and it is very rare for one photographer to get 2 lenses with this problem;
2)Lenses are easy to check for AF problems and at the equipment they had at the fair he checked my lenses OK, anyone probably can check that at any Nikon service center quickly.
3)If your problem is in your camera body it is derived by only one thing:
The CMOS Sensor is not properly aligned, or at the right distance, relative to the lens mount and/or Focus sensor(image) which sits in the lower part of the camera, under the mirror. This can happen naturally, by manufacturing defect or due to camera fall as well as other reasons... I would guess transport, wide ranged temperature variations, even some small detail in the production line.
That problem can have a few levels of severity:
1)Small misalignment that can be fixed by software, available at the service center only, without "opening" the camera;
2)Small misalignment that can be fixed by repositioning of the sensor, that requires "opening" of the camera (if you "open" it you might revoke the warranty depending on where you are!!!).
3)Heavy misalignment caused by a misalignment of the frontal and back parts of the camera body, which will require camera replacement.
Any Nikon service center can "check" what is the severity of the problem without opening it.
I sent mine for this check and got good news, mine was very light (my AF-S 50mm/1.4G required 7-10 points in AF Fine Tune portrait distances) and was corrected by software. Lucky me!!! It is perfect now up close and far away focus are OK!!!
The software correction is no biggie, well it is not very high-tech really, it's just Phase Sync adjustments of the AF Sensor as it's phase is not matching the Image Sensor position.
I suspect that the physical limits to this software correction is due to the size of the AF Sensor, if the Phase falls out of it, it would require manual reposition or replacement if not possible.
This has been done by every electronic technician (maybe not by software then) since well before I was born in the 70s!!! (giving up my age
)It is just a thing that we don't have in our (already too complicated) camera menus...
