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Im having some Focus problems with my tamron 17/50 f2.8 lense. (I have a D300s) I focus on one spot and take the picture and a completely different spot is in Focus.. i guess i have to use the Af tune function.. but dont know if someone has use it before... or has the same problems as i do....

Thanks for your help

Hey BlueD,
The AF fine tune can help you with you have consistent front or back focusing problem (but won't help if you have front focus problem when object is near and rear focus problem when object is far)

But before that, you said a completely different spot is in focus. Does it only happen when you are using the Tamron lens?
Or is it just any lens? If it happens with ANY of your lens, then it sounds more like a AF setting issue than the AF fine-tune to me..

so just to help you to diagnose the problem..

1. Which AF mode are you using?


2. if you are using single point focusing mode, did you use the center AF point? (lock then re-compose) or use one of the outside AF point?

3. Is the camera's in "C" , "S" or "M" mode?

4. Did you have the AF set to Release priority or focus priority?

Thanks for answering Yellow, i checked with my other lenses, and the focus issue only happens with the Tamron.

1. i am using the Single AF mode
2. lock then re compose
3. the camera is in "S" mode
4. i have the Af set to focus priority

okay, your settings seem okay

have you tried put a object in the center of the viewfinder, so just focus lock using the center point and snap a photo without re-compose? does it still have problem?


and maybe you can download the focus chart from here: http://focustestchart.com/chart.html (or somewhere else), follow their instructions and do the test at a few different distances and see if you got consistent focusing problem? (like always front focus)

ill run some more focusing test and see what happens....
hope i can get it worked out

i dont know what happend but... focusing issue was resolved

awesome! glad to hear that

thanks for your help

mmmmm i ran some more test.... and it is having front focus issiues.... but it only happens with the d300s, with the d80 the focus is accurate enough

i heard it's quite normal for some 3rd party lenses to work fine with one camera but not so well with another camera. Afterall, they just reverse engineer Nikon's AF system and get their lens to work with it.

Actually it can happen on the Nikon lens too, but very rare.