Focus issue, AF fine tune?

Eob

Senior Member
I feel like there is something wrong with the autofocus of my camera. For about 2 months, shots that should be in focus are not. It seems to just miss it. I bought the camera refurbished about a year ago. I've noticed the problem most often with my longest lens, Nikon 55-300. It seems to happen, but much less with other lenses, so I'm thinking that means it's a camera, not a lens issue.

I've thought about geting a focus pyramid to see if I just need to find tune the AF for each of my lenses, but it seems easy to screw up, and I don't have a sturdy tripod. If the issue is with the camera, would this even help? Looking for ideas.
 

Horoscope Fish

Senior Member
I feel like there is something wrong with the autofocus of my camera. For about 2 months, shots that should be in focus are not. It seems to just miss it. I bought the camera refurbished about a year ago. I've noticed the problem most often with my longest lens, Nikon 55-300. It seems to happen, but much less with other lenses, so I'm thinking that means it's a camera, not a lens issue.

I've thought about geting a focus pyramid to see if I just need to find tune the AF for each of my lenses, but it seems easy to screw up, and I don't have a sturdy tripod. If the issue is with the camera, would this even help? Looking for ideas.
Many things can cause a photo to have less than pinpoint focus. For instance, are you keeping the shutter speed at, or above, 1.5 times the focal length you're shooting with? That was a real sharpness killer for me when I was shooting DX.

Should you decide you want to do a proper test for front/back focus you're definitely going to want a decent tripod. That aside, though, there are ways you could at least do a rough test to see if there's an issue with front/back focus. I wouldn't make adjustments based on this sort of rough testing but it should help point you in the right direction. What you might try is using a ruler, yardstick or tape measure instead of one of those paper test-targets. When I started testing I used a ruler, leaned at a 45 degree angle, against a stack of books. I focused on a chosen number on the ruler and shot handheld. Two critical aspects to this testing is shooting the lens at it's widest aperture (e.g. f/1.8) and placing the target at the proper distance which is 50 times the focal length (e.g. 50mm lens has a focal length of, obviously, 50mm; so the math is 50 times 50, which gives us 2,500 millimeters which is two-and-a-half meters or just over eight feet)). You'll want enough light on your target so that you can shoot at 1.5 times the focal length or (e.g. about 1/125 for a 50mm prime) at ISO 100. You want the ISO as low as possible so digital noise doesn't give the appearance of improper focus of course.
 

nickt

Senior Member
You don't mention your focus modes. A basic starting point would be to make sure you are in single point and that the center point is selected. Next, be aware of your servo mode: af-s or af-c, or af-a. (I would avoid af-a for now). For af-s or af-c, get into your menu and be sure both are set for focus priority. If you are using one of those modes and you are set to release priority, you will be able release the shutter even if the camera is not finished focusing. That can give you random out of focus shots if you are too quick on the shutter button. Focus priority mode won't let you fire unless the camera sees focus. Also, if you are in af-c mode along with single point on a small subject, falling off target at the moment you click the shutter can cause you to miss focus. Once you are sure of all this, you can do some testing to see if autofocus needs some tuning.
 

Eob

Senior Member
I deleted everything that isn't sharp, but I kept this one, because she's my cat. AF single point focus, right on the eye and it's not in focus. I'll see if I can take something tomorrow that shows the issue better IMG_7935.jpg
 

Eob

Senior Member
Many things can cause a photo to have less than pinpoint focus. For instance, are you keeping the shutter speed at, or above, 1.5 times the focal length you're shooting with? That was a real sharpness killer for me when I was shooting DX.

Should you decide you want to do a proper test for front/back focus you're definitely going to want a decent tripod. That aside, though, there are ways you could at least do a rough test to see if there's an issue with front/back focus. I wouldn't make adjustments based on this sort of rough testing but it should help point you in the right direction. What you might try is using a ruler, yardstick or tape measure instead of one of those paper test-targets. When I started testing I used a ruler, leaned at a 45 degree angle, against a stack of books. I focused on a chosen number on the ruler and shot handheld. Two critical aspects to this testing is shooting the lens at it's widest aperture (e.g. f/1.8) and placing the target at the proper distance which is 50 times the focal length (e.g. 50mm lens has a focal length of, obviously, 50mm; so the math is 50 times 50, which gives us 2,500 millimeters which is two-and-a-half meters or just over eight feet)). You'll want enough light on your target so that you can shoot at 1.5 times the focal length or (e.g. about 1/125 for a 50mm prime) at ISO 100. You want the ISO as low as possible so digital noise doesn't give the appearance of improper focus of course.

thanks. I took a bunch of squirrel pics using single point AF @1/800 right on the eye to make sure that it wasn't just camera shake. They still came out just out of focus.
 

Eob

Senior Member
You don't mention your focus modes. A basic starting point would be to make sure you are in single point and that the center point is selected. Next, be aware of your servo mode: af-s or af-c, or af-a. (I would avoid af-a for now). For af-s or af-c, get into your menu and be sure both are set for focus priority. If you are using one of those modes and you are set to release priority, you will be able release the shutter even if the camera is not finished focusing. That can give you random out of focus shots if you are too quick on the shutter button. Focus priority mode won't let you fire unless the camera sees focus. Also, if you are in af-c mode along with single point on a small subject, falling off target at the moment you click the shutter can cause you to miss focus. Once you are sure of all this, you can do some testing to see if autofocus needs some tuning.


I almost always use af-s. I only switch for birds.
 

Horoscope Fish

Senior Member
I deleted everything that isn't sharp, but I kept this one, because she's my cat. AF single point focus, right on the eye and it's not in focus. I'll see if I can take something tomorrow that shows the issue better View attachment 247718
That does look a little soft... Are you shooting in JPG or raw? If you're shooting in JPG have you adjusted the in-camera Sharpness setting? If you haven't, you need to drop everything and do that now.

To make the adjustment, do the following:

  • Go into the Shooting Menu (Camera Icon).
  • From there drop down to "Set Picture Control".
  • Click right one time to enter the sub-menu.
  • Choose whatever Picture Control you normally use, probably "Normal", and click right again.
  • In the Picture Control sub-menu drop down to the "Sharpness" setting and move the slider from the very low default setting of "2", to +7 instead. Be sure to press "OK" to save this adjustment.
If you shoot using the "Landscape" or "Vivid" Picture Control, you'll need to adjust the Sharpness setting there as well; each of the Picture Controls have their own sub-menus and settings.
 

Eob

Senior Member
That does look a little soft... Are you shooting in JPG or raw? If you're shooting in JPG have you adjusted the in-camera Sharpness setting? If you haven't, you need to drop everything and do that now.

To make the adjustment, do the following:

  • Go into the Shooting Menu (Camera Icon).
  • From there drop down to "Set Picture Control".
  • Click right one time to enter the sub-menu.
  • Choose whatever Picture Control you normally use, probably "Normal", and click right again.
  • In the Picture Control sub-menu drop down to the "Sharpness" setting and move the slider from the very low default setting of "2", to +7 instead. Be sure to press "OK" to save this adjustment.
If you shoot using the "Landscape" or "Vivid" Picture Control, you'll need to adjust the Sharpness setting there as well; each of the Picture Controls have their own sub-menus and settings.
h

I'm shooting in raw. I had the focus point right on her eye, and parts of her body are more in focus.
 

Horoscope Fish

Senior Member
I'm shooting in raw. I had the focus point right on her eye, and parts of her body are more in focus.
Well I think your options are as follows:

1. Just jump in and adjust the AF Fine Tune setting in small increments until you see an improvement. This won't be the most precise method but it should help and it requires no special equipment (tripod, test target, etc.)

2. Invest in the necessary tools, such as a tripod and test target, and do a proper job of things.

3. Send your lens to a professional and have them do the adjustment for you.
 

Eob

Senior Member
Well I think your options are as follows:

1. Just jump in and adjust the AF Fine Tune setting in small increments until you see an improvement. This won't be the most precise method but it should help and it requires no special equipment (tripod, test target, etc.)

2. Invest in the necessary tools, such as a tripod and test target, and do a proper job of things.

3. Send your lens to a professional and have them do the adjustment for you.

thanks, I'll give that a try
 

INOV8TN

New member
Many things can cause a photo to have less than pinpoint focus. For instance, are you keeping the shutter speed at, or above, 1.5 times the focal length you're shooting with? That was a real sharpness killer for me when I was shooting DX.

Should you decide you want to do a proper test for front/back focus you're definitely going to want a decent tripod. That aside, though, there are ways you could at least do a rough test to see if there's an issue with front/back focus. I wouldn't make adjustments based on this sort of rough testing but it should help point you in the right direction. What you might try is using a ruler, yardstick or tape measure instead of one of those paper test-targets. When I started testing I used a ruler, leaned at a 45 degree angle, against a stack of books. I focused on a chosen number on the ruler and shot handheld. Two critical aspects to this testing is shooting the lens at it's widest aperture (e.g. f/1.8) and placing the target at the proper distance which is 50 times the focal length (e.g. 50mm lens has a focal length of, obviously, 50mm; so the math is 50 times 50, which gives us 2,500 millimeters which is two-and-a-half meters or just over eight feet)). You'll want enough light on your target so that you can shoot at 1.5 times the focal length or (e.g. about 1/125 for a 50mm prime) at ISO 100. You want the ISO as low as possible so digital noise doesn't give the appearance of improper focus of course.
Thanks for this procedure. I hip-shot something similiar when I was dissatisfied with the AF using a Tokina 11-16 on my D7200. I shot a tape measure on the floor at a 30` angle. Because of the low angle I couldn't reliably make out a target number on the ruler so I put a pen on the floor adjacent to the tape and aimed the spot focus circle where it touched the tape. Got some improvement. I'll get meticulous with your procedure and report here.

Sent from my SM-N950U using Tapatalk
 

Sempusa

Senior Member
I only dream my D7100 could be as sharp. I've had mine for over two years and am rarely impressed with a sharp image. Never have been so disappointed in a camera. There are just endless things to set that can go wrong.
 

Kevin H

Senior Member
I only dream my D7100 could be as sharp. I've had mine for over two years and am rarely impressed with a sharp image. Never have been so disappointed in a camera. There are just endless things to set that can go wrong.

Maybe you need a point and shoot camera if you can't get a sharp pic with a d7100 its your fault
 

Sempusa

Senior Member
Yeah, I think a cell phone would be sharper than the D7100 in this case. At least I could get a usable image, the Nikon just produces so much junk that goes in the trash. Glad there is no film involved, but even those SLR produced more consistent results.
 
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