Even though we ARE Nikon lovers,we are NOT affiliated with Nikon Corp. in any way.

English German French

Sign up Login
Home Forums Articles Galleries Recent Photos Contest Help Search News Workshops Shop Upgrade Membership Recommended
members
All members Wiki Contests Vouchers Apps Newsletter THE NIKONIAN™ Magazines Podcasts Fundraising

Focus problems with my D5100

cerberusjf

UK
4 posts

Click to send email to this author Click to send private message to this author
cerberusjf Registered since 02nd Dec 2011
Wed 18-Jan-12 10:30 PM

Hi,
I wonderi if anyone has any idea what could be causin the top centre focus point of my d5100 to be causeing problems?

what happens is this..

My problem is that the camera often cannot lock focus with this focus point, whereas it can when pointing at the same subject in the same conditions with the same settings. The camera can also appear to freeze when using the top sensor. It can also freeze when using area focus or automatic mode, but I never use those settings.

I have tried this camera with so many settings with the same results I am getting myself lost. Here are the settings of my latest try,.

Mode dial "S"
qual "norm" "L"
wb "auto"
iso "auto"
max sensitivity 3200
min shutter speed 1/160
single release mode
AF-S
single point AF
metering centered
ADL OFF
bkt OFF
Portrait mode
EC = 0
flash OFF
AF assist lamp OFF

The behaviour of the focus sensors selected is what I expected

D5100 behaviour of focus points with the 18-105

1. All focus points except the top one.

If the camera is pointed at an area of no contrast and the shutter button is released, the lens tries to focus. The lens does not achieve focus, the lens stops hunting and the green "focus achieved" lamp flashes. The lens seems to make two separate noises as it hunts, presumably as the lens goes from minimum to maximum, then back. If the shutter release is pressed again, the camera tries to achieve focus again by repeating the cycle. If the camera is then pointed at an area of higher contrast, focus is achieved, the lens stops focussing and the green "focus achieved" light in the bottom-left of the viewfinder is lit. The photograph is in focus.

If the camera is pointed at an area of higher contrast, focus is achieved, the lens stops focussing and the green "focus achieved" light in the bottom-left of the viewfinder is lit. The photograph is in focus.

The centre focus point is more sensitive and achieved focus more easily than the others.

The top centre focus point did not behave as I expected.

2. The top centre focus point.

If the camera is pointed at the same area of no contrast and the shutter button is released, the lens tries to focus. The lens does not achieve focus, the lens stops hunting and the green "focus achieved" lamp DOES NOT light up at all, it does not even flash once and the camera seems to freeze. The lens seems to make one single noise rather than the two separate noises as it hunts, presumably as the lens goes from minimum to maximum only. If the shutter button is pressed again, nothing happens, the camera will not try and focus, even if the shutter release is pressed repeatedly.

If the camera is then pointed at an area of higher contrast, two things can happen - the lens does not achieve focus, the lens stops hunting and the green "focus achieved" lamp flashes or- if the contrast is high enough, the camera "finds" focus and takes a picture. This picture can be front focussed though, the focus is not reliable. This may be due to a repeating pattern in the photo though.

If the camera is pointed at an area of very high contrast like the vertical edge of a monitor, focus is achieved, the lens stops focussing and the green "focus achieved" light in the bottom-left of the viewfinder is lit. The photograph is in focus.

If I put the camera in auto area mode. -

The camera sometimes will not achieve focus or the "focus achieved" lamp light up and the camera can freeze. Presumably this is when it uses the top middle focus sensor on a low contrast area.



To give you an idea of the conditions I was taking photos in, the photographs that could be taken had the parameters in the range

iso in the range 560 - 900
shutter speed 1/160
apperture f3.5

As the top centre sensor is behaving differently from the others of the same type, I believe there is a fault with this camera. As the top centre sensor is critical for the photos I want to take, this is creating problems for me.


This camera has been to Nikon (UK) twice and returned to me as in working order. I guess of they only test the focus with well-lit high contrast focusing charts, then they wouldn't see the problem. But I have explained everything to them several times.

Help, anyone please???
Thanks

Subject
ID
Reply message RE: Focus problems with my D5100
1
Reply message RE: Focus problems with my D5100
2
Reply message RE: Focus problems with my D5100
3
Reply message RE: Focus problems with my D5100
4
     Reply message RE: Focus problems with my D5100
5

G