lukevaliant Loc: gloucester city,n. j.

i read that i should calibrate this lens to my d7100,what is is everyones opinion on this?is it possible to use lens right out of the box?thanks in advance.

Bill_de Loc: US

Right out of the box is way to go. If there is a problem return it.

---

lukevaliant Loc: gloucester city,n. j.

thank you

imagemeister Loc: mid east Florida

You CAN use it out of the box - BUT, you really should test the AF and adjust accordingly - either by you or a pro -for best results.
.

Longshadow Loc: Audubon, PA, United States

I'd just slop that puppy on the camera and use it.

TriX Loc: Raleigh, NC

No one here can tell you without testing your specific camera and lens whether the AF is correct or not. Why don’t you test it and see if the AF is accurate at both 200mm and 500mm. There are many different systems available to test, but a simple system is to set up a series of objects, maybe a few inches apart at a diagonal and with the lens wide open and on single spot focus, aim at the center one and expose. If it’s in focus and the ones in front and behind are not so well focused, then the AF is accurate. Do that at several different focus lengths and at distances you’d normally shoot. If on the other hand, objects in front or behind the ones you focused on are correctly focused instead, then you can decide if further action is necessary. There’s also a test comparing Live view to the viewfinder that you can find online- just Google Nikon D7100 microfocus adjustment. It’s actually more critical on these long teles at max FL. For example the DOF on your camera at 500mm, f5.6 at 50 feet is only 7”

rmorrison1116 Loc: Near Valley Forge, Pennsylvania

I used mine right out of the box and it worked just fine. I use the lens on a D7200, D500 and D850 and it seems to work fine.

Longshadow Loc: Audubon, PA, United States

Drbobcameraguy Loc: Eaton Ohio

Use it. Then when you have some time take a yard stick or a foot long ruler. Set it at a 45 degree angle and put your camera lens combination on a tripod. Focus at the 6. If the numbers become out of focus before and after the 6 equally then leave it alone. He adjustment is just for front and back focusing. It will not make your pics sharper. If you notice on a photo that exactly where you focused is not sharp but slightly in front of or behind of it is Sharp then you need to adjust. You will most likely have to save at least 2 adjustments for the lens because focal length changes the adjustment.

therwol Loc: USA

I'll tell you why I broke down and bought a Nikon D850 to replace my D810. I don't think that the difference in IQ is 3 grand worth, but the frustration of adjusting the focus on lenses manually was just too much. Too much time. Too much trial and error. The D850 has a feature that adjusts the focus automatically in seconds, and it works quite well. I've read on this forum that if a lens is off, you should return it for another one or have the factory do an adjustment. The reality is that we buy lenses that are not quite right on in terms of focus, and many people don't notice it. You do notice it on a high resolution camera. Mirrorless cameras don't have this problem, however I'm not buying one (yet). I have too much invested in older lenses to consider it.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

This is why. In camera focus adjustments are a kluge at best - a ham-handed approach that is only a simple offset to the focus - at all distances and focal lengths by the same amount. Lenses can and should be adjusted at more than one distance and focal length - like some of the Tamrons and Sigmas because focus errors are rarely linear in nature.

The following quote right from Nikon's D850 Tips page says all you need to know:

"Use only as required. AF fine-tuning should be performed at the focus distance at which the lens is normally used; finetuning performed at short focus distances may be less effective with distant subjects and vice versa.

https://nps.nikonimaging.com/technical_solutions/d850_tips/useful/auto_af_fine-tuning/

The primary reason to have this feature, or even the manual version, is to perform a field adjustment in the event something is wrong. It was never intended to replace a proper factory calibration.

This, from Nikon again, confirms the intent of the AF Fine feature and when to use it and warns that it in the same as a factory calibration:

"AF tuning is not recommended in most situations and may interfere with normal focus; use only when required.

Service note: If your lens has a focus problem you should return it to Nikon Service as AF Fine-Tune is not intended to solve optical problems which will generally be outside of scope for this tool. If you have a focus problem which is always present with different lenses then this would indicate a camera setting issue or that the camera has received impact damage which is causing general defocus problems. Again return it to service."

https://www.nikonimgsupport.com/na/NSG_article?articleNo=000043897&configured=1&lang=en_SG

I have multiple bodies and a dozen lenses, and frankly I would feel like a dog chasing it's tail if I had to manually adjust each body for each lens. So I feel your frustration. I do trouble shoot a perceived focus error (camera or lens) and send in the offender to the mfgr - all of my lenses are tack sharp at all distances and in the case of zooms, at all focal lengths on all of my bodies without the need for AF Fine tuning.

So forget what you read on this forum. I've given you the words from the source. If you want to still believe that AF Fine tuning is a good, permanent solution to focus errors, then go right ahead believing . . .

DaveO Loc: Northeast CT

TriX Loc: Raleigh, NC

There are two possible factory calibrations - one lens matched to one body (if you send both in AND they are both from the same manufacturer) or both adjusted independently to be within the factory tolerance. So no dimension or specification is exact - everything has a tolerance (I mention this as the quality manager for a high precision aerospace manufacturing company where we calibrate EVERYTHING). The net-net is that both the lens and the camera can be within factory tolerance, but when mated, the tolerance stack up creates an unacceptable error if max focus accuracy and sharpness is the goal. On the other hand, if you factory match every lens you own to one body, then it won’t be matched to another body, and let’s not forget the inconvenience, potential damage, cost and potential shock which can change the calibration during shipping. There is also no reason to believe that their “calibration” is anything different than applying a “blanket” change to the AF. Ideally, there would be a curve of corrections applied such as that created using some aftermarket lenses “docks”, but we have no way of knowing if the factory has this ability on all (or any) of their lenses.

Having said that, I will gladly grant that on most cameras with MFA, there are a max of two adjustments for zooms and one for primes, so not perfect as the “correction curve” that would be ideal, BUT it is very likely, if properly applied, to be preferable to no adjustment. The claim is routinely made that it can cause misfocusing (but if you don’t like the results of your calibration, just turn it off or reset to zero). It is also claimed that it is appropriate only at one distance and at one FL for zooms or can prevent focusing at infinity. Obviously, I can’t test every every possible lens, but I have tested a lens at multiple distances and infinity, and found that while the adjustment does vary some with distance, the KEY is that at every distance, it was an improvement at EVERY distance and focused fine at infinity. I published the results on UHH (https://www.uglyhedgehog.com/t-508300-1.html), and if anyone disagrees with the conclusions, I invite them to repeat the test on their lens(es) and publish the results.

For all those that claim to have never needed to adjust a lens, I would answer that without trying, one never knows if their lens can perform better or not. Needless to say, I, and many pros, do calibrate their lenses. I am in no way as good a photographer as some that do not calibrate, but I can represent that by careful calibration and measurement, I know that my lenses are delivering the max performance that they're capable of. This is one of those “religious” issues like Canon vs Nikon, PC vs Mac, etc., so those that don’t calibrate are unlikely to try it, and those that do, believe in the results they get. And of course, one has to wonder why manufacturers include this feature if it has no value when properly applied.

Drbobcameraguy Loc: Eaton Ohio

The adjustment in Nikon cameras has zero being on sharpness. It adjusts back and front focus. In other words making sure the camera focuses exactly where you focus it. Not a quarter inch behind or in front of or more. I am a perfectionist. I adjust all my lenses and use the sigma dock to adjust a lot of the perimeters on my sigma lens. None of the adjustments will make a lens sharper. It can make it sharp where you are actually focusing instead of slightly in front of or behind. If a lens is not sharp at any focal length then it has a defect. Usually due to decentering. You can test for that. I agree with you on everything just want the op to understand to look at his photos at 100 percent with the focus indicator on. If the photo is not sharp under the focus indicator look at the photo behind and in front of the indicator. If you see it is sharp anyplace other than the focus indicator it needs adjustment to bring the focus forward or move it backwards until it coinsides with the focus indicator. Of course the shot should be off a tripod at a high shutter speed and normally if I want to test it I use a test fixture similar to this.

TriX Loc: Raleigh, NC

Just to clarify, correct AF has everything to do with sharpness - an out of focus image cannot be sharp. As you say, it affects focus accuracy. If one decides to do this adjustment, the main issue as I see it is a subjective judgement as to what’s in focus - I’ve tried the angled scales, and that’s the issue - trying to judge exactly which number is in the best focus. If you want an actual objective, repeatable measurement, the FoCal system by Riekan is the answer. Not only do you get an accurate AF calibration, you can also get a curve of acuity vs aperture (which I find invaluable for telling where your lens is sharpest, how much degradation from diffraction at smaller aperture and an instant measurement as to whether the new lens you just bought is up to snuff) and a graph of AF repeatability. It’s the best $90 (for the professional version) I’ve spent since I bought my first Nikormat for $125 in 1968. Of course if you’re using a MILC, then AF accuracy and MFA is no longer an issue.