Lens calibration (Page 2): If they did it gratis, great. If I remember correctly, they want $160 per body and lens combination plus shipping. After a while, that gets expensive plus...

abc1234 Loc: Elk Grove Village, Illinois

47greyfox wrote:

I have a Sigma 100-400 Contemporary that was focusing fine then started going soft at moderate focal lengths. I talked to Sigma after starting a calibration using their dock. Thirty minutes into the process, I called Sigma with a few questions. Their suggestion, “box it up and send it to us, we’ll calibrate it.” Done! I should have it back next week.

If they did it gratis, great. If I remember correctly, they want $160 per body and lens combination plus shipping. After a while, that gets expensive plus the time not having your gear. That is why I went to FoCal.

47greyfox Loc: on the edge of the Colorado front range

abc1234 wrote:

If they did it gratis, great. If I remember correctly, they want $160 per body and lens combination plus shipping. After a while, that gets expensive plus the time not having your gear. That is why I went to FoCal.

I see your point. Yeah, mine is being done under warranty. Faced with a $160 quote, I'd be looking for alternatives. Another risk reward scenario of life.

abc1234 Loc: Elk Grove Village, Illinois

I agree with TriX and disagree with nikonbill. I looked at the former's earlier post. The data posted were pretty much a straight line as judged by linear regression. However, five to fifteen feet does not represent much of a range although the closer you get, the more the error due to the shallow depth of field. FoCal does give you an "infinity" so the real test is adding one or two distances to those they recommend.

From TriX's limited distance range, you can safely interpolate the adjustment. This overrides nikonbill's objection.

FoCal could not get reliable data for one of my lenses, a Sigma 18-300 kit lens, at 300 mm. 18 mm was ok. I set the zoom to 200 mm and when FoCal warned me of that, I overrode it and calibrated it successfully. I would imagine the same is true at intermediate distances. Caution: the MFA scales for FoCal and the Sigma Dock are not equivalent. Do not take a FoCal adjustment and set your lens with the Dock.

abc1234 Loc: Elk Grove Village, Illinois

47greyfox wrote:

I see your point. Yeah, mine is being done under warranty. Faced with a $160 quote, I'd be looking for alternatives. Another risk reward scenario of life.

Good for you. When I bought a new lens, Sigma told me I would have to pay for it. Needless to say, I was not very happy about it. However, in the long run and if you are so inclined, you are better off buying FoCal so you can check your lenses periodically.

PS FoCal just released a significantly improved version. I have yet to test it so do not know how true their claims of new and improved are.

RichardSM Loc: Back in Texas

I have question is it really the lens or the camera not being properly designed to handle mostly other manufacturers optics and that’s the reason why you folks buy all these after market focus products.

I don’t own any other manufactures lens, I’ve stayed with OEM I don’t have all these issues.

Strodav Loc: Houston, Tx

billnikon wrote:

DON'T DO IT. Leave it alone. You will be sorry.

If you decide to make an adjustment, you can always put it back to the defaults (zero) with absolutely no problem. I can't see any reason not to learn how to tune if you have the time and a little aptitude. Even if you find you don't need to make any changes, you will gain a greater understanding of how AF works, which is a good thing.

abc1234 Loc: Elk Grove Village, Illinois

RichardSM wrote:

I have question is it really the lens or the camera not being properly designed to handle mostly other manufacturers optics and that’s the reason why you folks buy all these after market focus products.

Does not matter. Both change over time.

TriX Loc: Raleigh, NC

abc1234 wrote:

Good for you. When I bought a new lens, Sigma told me I would have to pay for it. Needless to say, I was not very happy about it. However, in the long run and if you are so inclined, you are better off buying FoCal so you can check your lenses periodically.

PS FoCal just released a significantly improved version. I have yet to test it so do not know how true their claims of new and improved are.

I haven't checked in the last couple of months, but about two months ago, I upgraded to the pro version. One of the new features was an aperture vs acuity test which provides very interesting results on where your lens is the sharpest or at least acceptably so as well as being able to compare the absolute acuity of your lenses (makes it very easy to spot a bad copy). Interestingly, those old adages of a lens being sharpest 1-2 stops down from wide open or sharpest at f8 do not always prove to be true.

abc1234 Loc: Elk Grove Village, Illinois

TriX wrote:

I haven't checked in the last couple of months, bu... (show quote)

FoCal certainly pumps out the information. Other than the microadjustment and aperture sharpness, I am not sure how helpful it is. Most of that you cannot adjust. If you are buying lenses and want the best of the bunch, then perhaps FoCal helps. I wish their descriptions of all those tests were better.

That old saw about being sharpest at about two stops down really is pretty true for my lenses. The values are at the top of the curve so the lens does have some latitude. F/8 might be go in the old days when F/3.5 was considered fast. What surprised me was how much sharpness degraded at smaller apertures. I liked stopping down for the depth of field and avoiding focusing errors. Now I see the price I paid was sharply declining lens sharpness. My default aperture is now two stops down.

Don, the 2nd son Loc: Crowded Florida

billnikon wrote:

DON'T DO IT. Leave it alone. You will be sorry.

Good advice! I typically ignore good advice but not this!!

Strodav Loc: Houston, Tx

RichardSM wrote:

I have question is it really the lens or the camera not being properly designed to handle mostly other manufacturers optics and that’s the reason why you folks buy all these after market focus products.

Major manufacturers like Canon, Nikon, and Sony don't care about 3rd party lenses. Their reputations are at stake with their own stuff and don't want bodies and glass coming back for $repairs$ under warranty and want to avoid bad reviews. It's up to the 3rd party lens maker to make sure their equipment works on compatible bodies.

I am invested in Nikon and have found that Nikon glass AF is pretty close to dead on out of the box, but Sigma and Tamron lenses almost always need tuning to get the most out of the lens and camera. I think that's why they sell the USB Dock and Tap-In. So my recommendation is that if you are not into tuning, buy the manufacturer's glass, but if you are willing to tune, you can save quite a bit of money with results that are very close to the manufacturer's equivalent.

johntaylor333

2mishka wrote:

On kits or digital software to calibrate my camera and lens. Any suggestions?

I use FoCal by Reikan and like it.

abc1234 Loc: Elk Grove Village, Illinois

Strodav wrote:

Major manufacturers like Canon, Nikon, and Sony do... (show quote)

When you say "dead on", how do you know that?

TriX Loc: Raleigh, NC

I’ll just add that if you shoot landscapes or scenes with the lens stopped down and a large DOF, then you may never notice if your lens is front or back focusing - the DOF “hides” the error. On the other hand, if you tend to shoot wide open or long teles with a DOF of inches or less, then it can make a big difference. That may explain why some excellent photographers who shoot landscapes find it unnecessary, while others, who shoot portraits wide open find it critical.

Of my 7 Canon lenses, 5 of them “Ls”, all but one required some MFA to get it spot on wide open, and 2 would have been unusably soft without calibration. BTW, interestingly, the MFA per lens didn’t change appreciably when I changed from a 5D3 to a 5D4 body. If you take a look at the before and after shots from a 135 f2L link in the post I referenced, the difference in sharpness is apparent, and that is a lens noted for its sharpness.

Strodav Loc: Houston, Tx

abc1234 wrote:

When you say "dead on", how do you know that?

Live View (LV) uses Contrast Detection Auto Focus (CDAF) and AF uses Phase Detection Auto Focus (PDAF). LV will give you the sharpest result your camera and lens are capable of as long as you are using GOOD TECHNIQUE and LV is more consistent than PDAF. So, set up a resolution target, like a newsprint page at a 30 to 45 degree angle, with a good focus point and take some LV and AF shots. IF the LV and AF shots are equally sharp, no need to do anything. If the LV shots are sharper, then you might benefit from tuning. If the AF shot is sharper than the LV shot, something is wrong. Further, because your target is at an angle, you should be able to see if your AF shots are front or back focused.