Focusing issues with Nikon 18-35mm f3.5-4.5D on D3200

Question

I have a Nikon D3200 and I have used in the past year and half a 35mm f/1.8 G DX prime lens . I have rented several other lenses and I also have a 50mm 1.8G prime too (I'm sure that some of you will think that's redundant)

I'm used to having the half-click to autofocus for me and be able to position myself to get the shot that I want.

I have recently purchased a Nikon 18-35mm f3.5-4.5D - as I wanted a wide angle lens (as I have rented a 24mm before) with the capability of zooming slightly also.

I have read that this lens cannot autofocus due to my camera not having an AF motor.

However as I am fiddling around with the lens to take a stationary shot - I cannot get any of the shot within focus regardless if it set to 18 or 35 (or middle) and manually adjusting the focusing ring from infinity to the lowest setting.

Can someone please explain what can be done with the lens to focus properly or the settings that I should be using etc.

I have tested at f/3.5 and 1/60-200 - in low light + flash to f/4.5 and 1/60-200 + flash - with no success in fixing the blurriness of the pictures.

Note: my goal for the lens is to cover family events where there will be large (20 people in a shot) frames (hence why I wanted the 24mm in the first place) so I'm not shooting stationary landscape so any setting recommendations that I should be trying please keep that in mind so that I can have a middle ground to work on.

Answer 1

Screw-driven autofocus lenses tend to have very short throws to enable the motor in the camera to get through the entire focus range quickly.

The trade-off for this is that it takes a very small amount of angular movement in the focus ring to pass through the zone where the AF system thinks the focus is correct. The body is capable of the very minute steps to make this work quickly and accurately, which your hands can't do. If you attempt to focus quickly, odds are very good that you'll blow right through the correct spot before the AF system can notify you and you stop moving the ring. The AF indicator may blink as you pass the right spot. (On higher-end bodies, there are two arrows flanking the indicator that indicate which side of focused you're on once you get near the correct focus. Seeing a transition from one to the other would be an indication that the camera and lens are getting along just fine and you're rotating the ring too quickly.)

The best thing to do may be to not use the AF system at all. The D3200 has a removable focusing screen which can be replaced with a third-party model that has a split image or pentaprism focusing aid. This will allow you to better coordinate your hands with your eyes and may get you better results.

Answer 2

Could you post a 100% crop (central part) of an image you considering blurred? Sidenote: why not use a kit Nikkor 18-55mm DX, it has same lame f/3.5-5.6 but adds VR and longer tele (~70mm equivalent for nice portraits) for less money. Also I believe there is no 50mm DX lens in existence.

I personally played with D3100/18-55VR couple of weeks ago and I should say it is a terrific combo.

What I suggest is to take a picture of a long ruler or other test sample, where you try to focus on some known number (whatever is in the middle) while shooting at oblique angle like that: http://regex.info/blog/photo-tech/focus-chart. But don't spend too much time on that, as soon as you see real performance of your camera, forget about it.

The purpose of that test is to check whether your eyes are not OK, or optical distance between lens and focusing screen is not same as between lens and sensor.

Beware What you might consider blurred can very much be OK. Also, don't use your camera's LCD for checking focus, do it on nice and bright monitor.

Answer 3

The 18-55 VR II (the current collapsible model) is a very fine lens optically, but in a cheap barrel. It easily outperforms the 12-24 at 24mm on DX when correctly focussed. If the autofocus works for you, it will outperform the 18-35.

Wide angle lenses are difficult to manually focus - you will at least need an eyepiece magnifier. The D3200 does indeed have an electronic rangefinder - a series of dots in a line either side of correct come and go as you move closer to correct focus.

Note that only the most razor sharp lenses look crisp at 100% view with 24mp DX. Normally the image is somewhat soft at 100% view, but still records plenty of information for sharp prints or web files.

My 18-35 AF-D doesn't quite make infinity on my D3200, but is fine on other bodies. Check that this is not your problem.

Your 18-35 will be easy to sell if you don't want a fullframe camera, as many go fullframe without realising the true cost of lenses. It's one of the better cheaper options for full frame users.