I calibrate all of my lenses first, before using them. It is less likely, on a DSLR, that a camera/ lens combination will achieve optimum focus right out of the factories.

+2541968joey That's great. I will do the 150-600 soon as well. It's in TX now out to a client so I'll get to it when it gets back :) So glad this was helpful for you.

How did you calibrate infinity , how long distance ? i try to calibrate Sigma S. 150 - 600 mm , thanks :)

I bought 2 of these lenses last year. One was better than the other out of the box. I am interested in the calibration to the camera that you're speaking of.

Thank you!. I've got it for rent of course :) but one thing to note if you decide to buy. I am not a fan of the 120-300's tripod collar. Look for my other video, the one about tripod collars, and see how I modified mine. It's better, but still not perfect. It's called "Tripod collars review and fix"

I'll have a look - but I'm very optimistic that the original tripod collar will fit my needs. I am even satisfied with the tripod collar on my 100-300 f/4 that everybody calls garbage. :)

Which Camera are you using?

With DSLRs there's differences in each body that can mess up factory settings. Some cameras have these adjustments built in but any adjustments made would be applied to all lenses and that may not be needed. This solution is great since it bakes the adjustment into the lens itself, but also, it's then "tied" to that camera body. If you calibrated your lens to your camera, and then your friend borrowed it, it's possible that it would not be optimized for their camera. Using Live View in a DSLR will overcome these issues but it'll also slow you WAY down :)

Awesome. I'd like to point out the custom nature of this process though. The settings are specific to the camera-lens combo. While I'd like to think it's all about the lens, the camera body can have some "problems" too that this calibration overcomes.

I might be able to get one done for the Sport model, I don't own the contemporary model.

Brent Rents Lenses Thanks, is far is I know they are the same. Only the sport have water proof and dust resistance (or something like that..).

There's slight differences. The Sport has a larger front element for instance.

I'm sorry I didn't get this done before I sold that 150-600 Sport lens. I've shut down the company and have liquidated all the gear.

It varies per lens, but you should get it as close to the estimated points as possible. In this video with the 120-300 lens it has the closest focusing point, that's rather easy to figure out. And then there's infinity which is rather silly realistically speaking. You're just not going to be able to make a judgement off this target when you place it so far away. So any contrasty texture item will work in my opinion. The two intermediate points are where you have to make the best judgement call. Will you even be able to see the target large enough in the frame if you place it 30ft away? Probably not. But again, a contrasty texture element (a brick wall for example) may work for you. Also, since Depth-of-Field calculates longer at these further distances anyway (subject to camera distance) it's not as critical as the closest focus point where DOF is calculated much shallower.

Thank you! I'm glad you found it valuable.

I have now heard the same thing, start at infinity first. And yes, the lens would keep the same calibration settings from camera to camera, but who's to say that those settings are right for other cameras? You can't guarantee that. However, I've had this lens go out plenty of times and I've never had anyone complain about the focus being off.

What's probably going to be more significant is something like temperature differences which can make difference in the AF system's throw.

Calibrate with the dock on your main camera body, and use the in body fine tune with the second camera to your average working distance and Focal length.

I want to know the same, just got the 150-600 and at 600 at infinity its soft, how far away should the target be 200ft, 400ft? to do the infinity setup

Awesome, Glad it was helpful for you.

No I don't think it will have any benefit for that. You might still benefit but the biggest benefit will be experienced by DSLR users.

Sorry I missed your question earlier. I just chose a subject very far away that was contrasty and compared shots obtained via live view to the shots obtained via regular AF. The chart is useless at that distance.

If you look at 5:41 it tells you exact distances. you must do 2.5 m (Minimum distance) - Then roughly 6.25 m - then 10 meter - Then Infinity (So anything that is in focus at infinity distnace (Choose your distance of choice) But the most important is you keep the distances the same across the whole lens tens for each section

Not really, it's a tiny box it comes in and from what I remember, there was a sheet in there, but not very well documented. The process is different between prime and zoom lenses since the zoom lenses have multiple points to calibrate.

I just used something close to the guides. It's different for each lens, but the focus scale item shows a general area where the distance should be and I found that getting it close to that suggested range worked well.

It can depend on which AF point you were using. In your camera, you don't have as many "Cross type" AF sensors as newer bodies. Additionally, you could try the same shot using live view. If it's still blurry then there's something fishy going on. If you were using the center AF point then you should be good, even in lower light. That's guaranteed to be the most sensitive AF point. There might be others, I'm just not familiar with the AF array in that specific camera and I'd have to look it up to be sure.

Thanks for writing, and sorry for not making that clear in the video. But you're right, that's impossible to deal with for the focus target. I ended up finding an object that's rather contrasty and textured such as a brick wall. I then used live view which uses the contrast in the scene to focus the lens and then I used the standard AF to focus and compare that way. For mine I actually found that it was spot on so I didn't need any adjustments at the infinity mark.

I used wood railing at 45 degrees for all my calibration shots. Outside, tripod, ISO 100, 1000th, RAW. For the 150mm and 50ft, I pixel peeped to determine if the front and back blur were about the same distance from the center focus point. In my experience it was way easier to instantly see the need for adjustments using outdoor wood railing shots at 45 degrees than trying to use printed or purchased focus charts.

Belated thanks for your reply. I will give that a go.

That is a fantastic solution! Thanks.

Sure thing. :)

Yeah, I don't think they make one for MFT. However, mirrorless cameras tend to not have the same struggles with getting focus right. And many cameras offer their own adjustment. See if your camera has a micro focus adjustment and hopefully that will be of help.

If possible, it'd be best to do it on your camera. There are specifics to your camera body to get this done right. So in general, yes, it's easy to use. But it is rather technical and you need the focus target. If you sent your camera and the lens to someone they could do it for you. I could do it, and if you shipped it I'd be able to get it back to you in a couple days. It'd be about $50 plus return shipping. If interested, please contact me via the contact form on my website, we'll sort out the details on email.

Brent Rents Lenses Someone recommended FoCal so I might try that instead. It works with other lenses too apparently. Thanks though!

Oh yeah, that's a good one for sure. Very versatile. Works with the camera's AFMA though and not the lens specifically. Either option will get you what you need, but the sigma dock is the only way to update the firmware if it's needed.

Brent Rents Lenses I tought FoCal adjusts both the camera and the lens at once...pfff, I'm so upset.

FoCal connects to your camera and makes the necessary adjustments if your camera supports Auto Focus Micro Adjustments. It works great. But it won't do anything to the lens specifically. The sigma system requires you to shoot focus target pics, disconnect the lens, connect it to the dock, load the pics on your computer, analyze the "imperfections" in the focus, program specific adjustments to the lens based on what you're shooting and analyzing, then do it all over again to check the results and continue fine tuning until it's right. It's a slow process, but it works. FoCal would be a faster process since you can do it in about two shots. The sigma system adjusts the lens only, not your camera. But that's not a guarantee that it'll work perfectly with another camera since cameras do have differences. So the FoCal takes the lens and camera differences into account and adjusts the camera to achieve perfect focus. The sigma system takes the camera and lens differences into account but it adjusts the lens to accommodate for inaccuracies. I do like the sigma system better because with my gear I've noticed that the differences in camera bodies are very minimal. An adjustment to the lens works across many bodies (in general) but if you want it absolutely perfect, doing it on the camera you intend to shoot it with is best.

Mine is at 45 degrees, it helps because the intervals are regular and easy to track. A home made system, if made of sturdy materials, should be able to accomplish the same goals. The ruler is only used to determine whether or now you have front or back focussing going on. Without it, it'd be tough to know which direction to go with the adjustments.

Thanks for asking. I initially tell people to use the hyperfocal distance of their lens. IT's not "infinity" per se, but it's close enough. For your lens at f/1.4, it's 69.7 ft. this is found using a depth-of-field calculator such as www.dofmaster.com/dofjs.html (I assumed you're shooting a full-frame camera. If not, adjust the settings on the page accordingly). However, placing your focus target at that distance is essentially useless since it will be so small. So what I do is I switch to Live View (for DSLR system this should still work, for advanced mirrorless systems there's nothing to really compare it to), so you're in live view. take a pic. Then switch to standard mode where you're looking through the viewfinder. Take a pic of the exact same framing. You should also be tripod mounted. Compare those. Your subject should be a flat contrasty and textured subject such as a brick wall. Don't angle your camera. Have it pointing straight forward, not angled up or anything like that. Compare your images, If you need adjustments to your focus settings go ahead and make them. Usually, in my experience anyway, infinity hasn't needed to be adjusted. Good luck!

@@BrentBerghermPhotography thank for the info bro!

I hope I am understanding properly. It sounds like you set up the focus target at the recommended distance (according to the focus zones in the software) and you're needing to get the lens to focus on that spot? Use the AF in the lens to achieve focus. For zoom lenses, use the same range as established in the software, but just know you're probably not going to get it "exact" unless you were to check the meta data of the file and just do a trial and error (since zoom settings are saved to the metadata for most lenses). Hope this helps.

@@BrentBerghermPhotography thanks, I started doing it by trial an error

I start with the lens set to 120mm on the zoom ring. The widest setting on the zoom ring. That's what I was referring to and I hope that's what you meant :) As for my measurement in inches, multiply by 2.54 to get cm. So that 55 3/16 of an inch is 140.18 cm.

For infinity, I just used the live view with a contrasty subject. The calibration target will be too small. Compare that to the regular AF. As for whether or not you need to calibrate all 16 points, I say sure, why not? But certainly it's not required. But going through the trouble is probably worth it.

Hello, quick question.... doesn't Live view uses a different system when it focuses?

Yes, it does, it uses contrast adjust to achieve focus. That's why I use it to compare infinity focus. The focus target is just too small to focus on and to inspect afterwards. Manufacturers, like Sony, are putting a ton of phase detect sensors on the imaging sensor itself. Canon also does this with the 7D2, but on the canon line anyway, they're only good for shooting video. So things are going to change for sure, but for now, that's still the conventional wisdom, where live view is using contrast of the scene's objects to achieve focus.

Anywhere within that range and you should be good. I'd go closer to 2 feet because your depth-of-field will be much narrower at that as compared to 8.5 feet, and any missed focus will be more noticeable because of it. Plus, it'll probably be easier since your focus target is so much closer anyway.

@@BrentBerghermPhotography thank you for taking your time to answer

Infinity is a tricky one since the focus target needs to be too far away in order for it to be useful. So in that sense, what I did was to compare it to an object that is relatively textured, lots of detail, that is really far away and I did focus with the regular AF and with the live view. This method is still somewhat iffy in my opinion because things are so far away and you really need a good subject to get good results. But it's the easiest/best option to do given what most of us have available to us (i.e. if I had an optical bench to test these things with lasers and such I could get better results, but I go for the methods that most folks will be able to do on their own). Hope this helps. p.s. someone else posted this link. Looks pretty good, and also uses the live view function to achieve the initial focus. However, it's not as accurate as using the sigma dock since the dock will provide four different distance points for setting the lens adjustments. kzfaq.info/get/bejne/beB1aJObqLu0mIE.html

I've had folks recommend the infinity first. I've not personally tested it both ways to ensure that one is better than the other. But I believe conventional wisdom is to do infinity first. However, since we have four different areas where we judge the focus accuracy I don't see it as a big deal. If we only had two adjustments, or only one, then I'd certainly see it being an issue and would recommend infinity first. Just my take on it :) I'm always willing to see what others do.

Using the 2 second delay would prevent vibration induced by you pressing the shutter button, but it would not prevent any vibration that might be caused by the mirror flipping up at the time of the exposure, unless the mirror flipped up seconds before the shutter too, right?

...or just use both mirror lockup and 2-second auto shutter.

The software should have an item that shows you how far the range should be (in the grid where you input the settings modifications). The only challenge is setting the infinity. I use a brick wall or other flat object very far away and then simply compare the live view to the non-live view focus results. Live view uses a different system to achieve focus and is virtually always accurate.

The fringing is easier to see and helps one target the lines that you actually have to judge. When it's fine detail work like this it's just nice to be able to target it so quickly. And I view it as an additional aide but since you're looking at the center of the lens (or very close to it) you're pretty much guaranteed symmetry. But even if it's not symmetrical you get so close to the ball park of where you need to be the pixel peeping for complete accuracy becomes so much easier to target.

I understand your convenience argument but from a physics point of view there is no reason why max BW sharpness is centered between colored fringes. Best sharpness occurs centered between equal BW unsharpness, not centered between different wavelengths of color fringing. In your case above I would say that best sharpness is at -2 (- 3) mm, not at 0.

Yes, different wavelengths of light certainly do refract at different angles. And the coatings on lenses can alter that so there's a few built in inaccuracies when using this method. However, using it as a quick target to hone in on the good details is still sound. It's not articulated as such in the video but hopefully folks can be reading these replies as well and get the full picture.

So you are erasing critical comments. Amazing !

I did not erase any comments. At least not on purpose. Please feel free to restate whatever you'd like to ensure it's stated. I'm way more interested in folks having the whole picture and you have helped in that regard. I am grateful. But I can see all comments still here in the thread, sorry if they're appearing truncated for you.

You pretty much have it right! My measurement was from the sensor. On the part where I was focusing at the closest mark on the lens I did have to adjust the position of the target a bit after I got into it so that I could actually nail the focus, so maybe measuring from the lens front would have prevented that. But you're on the right track! Keep it up :)

Thank you!! so much :)

question how do you measure for infinity calibration?

I selected a subject at a very far distance that was contrasty (trees without leaves in my case). I then shot it with live view which uses contrast focussing and regular AF which uses the phase detect focusing. I then compared the shots. Might not be the most "scientific" but a target at that distance is useless.

i see thats makes sense, i was trying to figure out how to get it to focus on that small target. I will just have to eye ball it on trees or buildings lol thanks

I was noticing, at least for this lens, that the chromatic aberration shifted one way when it was front focused and the other when it was back focused. So if you happen to have that going on in your image you might be able to make a determination that way. But you'd have to compare it to the other areas where you were able to fine tune the focus, and then if you put in a negative number to correct the focus at one point (and the CA was a certain patter/direction) then do the same type of movement for the infinity focus (negative number in this example). Hope this helps. :)

Thanks will try it, I read another user takes fotos of roof tiles far away, to assess it that way, so gonna try that as well

I used the center AF point in the camera to focus on the cross circle item on the focussing target. The scale to the right is to indicate where the actual focus is at, a little in front of or a little behind the intended focus target. You then use the software to make adjustments.

thank you

I used the Data color spyder lens cal. Here's a link: www.bhphotovideo.com/c/product/736849-REG/Datacolor_DC_SLC100_SpyderLensCal_Autofocus_Calibration_Aid.html

+actionmedia4all I actually had to get rid of the target when I went to infinity. I ended up testing infinity focus with a distant wall and compared it to the contrast focus achieved with live view. The 120-300 did really well at infinity, it was the closer focus areas that needed the adjustment. Also, the target is so small when it's far away like that. It basically becomes useless, it's impossible judge any DOF since you're at infinity anyway, so it's more about how accurate is it at nailing infinity focus and a larger object is needed to make that judgement.

No it won't matter which you do first. Sigma splits the focussing areas into for regions. Closest focusing, Infinitiy and two somewhere in the middle. It's generally evenly split and is unique to each lens.

also, for infinity, the target is so small I found it better to just use something that's flat and really far away. You could always look up the distance that the lens focuses at, but let's face it, it's called infinity for a reason :) so as long as it's really far out there it'll work (and it's really even in texture etc.) Then I compared contrast focussing achieved through live view and the regular phase detection focussing achieved through the af sensors. It feels more like you're grasping at straws with this approach, but with patience and determination it can be done. The hardest thing is to have your computer there to make the shooting and comparing really convenient.

Awesome, that's a good rule of thumb to go by. I'll keep that in mind! Thanks.

wanted to ask the same thing, but 4 times the focal lenght is not good for infinity focus. before the calibration dock thing, 5 times the focal lenght was the standard focus distance for lenses. you can use something like dofmaster to calculate the hyperfocal distance for the lens, its easy on a wide prime, harder to accomplish on a tele lens, since a 200mm for ex gives you a distance of a couple of hundred meters to be able to trully get the infinity focus at the widest apperture.

If you have greater depth-of-field the changes are not as evident and it's more difficult to see precisely how the focus control needs to be adjusted.

Wow, I would think it's not normal but my specific experience with this process is not as robust as others might have. In this situation I'd consider using both my camera's AFMA adjustments combined with the Sigma options to make adjustments. However, that can open up a whole new set of troubles. How are your other zoom calibration settings? are they all this far off or are they much better?

@@BrentBerghermPhotography hi. im not completely sure if im doing it correctly... a little nudge here or there and when i try it again i get different results. not drastically but this time i got that 20 down to 19+. still alot higher than the others though which range from 0 to 5+ to 12+. i dont suppose you know how to measure the 4 slots for infinity? im not sure what the distance should be and how to compare out of focus objects that are out or in focus. How did you do it? thanks

@@trydowave Good, sounds like progress. For infinity, you'll need to look up the distance settings for your lens. For and 18mm lens at f/5.6 the hyperfocal distance is 6 feet 4 inches. If you set your focus at this distance (set an object at this distance and focus on it) you should also have all items from here to infinity in focus as well. However, that's not the same as shifting your lens to the focus of infinity. When I look up a DoF table, that same lens at that same aperture with a subject distance of 6 feet only (not including those four inches) lists the far DoF area as 119 feet and 10 inches. This is insane for 18mm. After that (subject distance of 7 ft on this DoF table) the far focus point is listed as infinity. Long of the short of it is you get a diminished benefit the further out you go because your subject you're shooting (a focus target etc) will be so small in your frame it's not worth it. So I generally will go 2x to 3x the hyper focal distance of the lens and just stick with that. In your case you're at just shy of 13 ft to just shy of 19 ft for the 2x-3x of Hyperfocal distance. Use that for Infinity and you should be in the ballpark at least because beyond that, your calculated DoF will include infinity and all should be in focus anyway.

My numbers here are based on a full frame camera. You'll have slightly different numbers if you're using a crop sensor camera.

@@BrentBerghermPhotography sorry... forgot to mention. i have the Sigma 18-35mm 1.8

You should us AF. The purpose of the exercise is to calibrate the AF system. You certainly could use MF to get what you think is the best result and use it as a comparison, but using the AF a good idea here.

if you're talking about the GH5, that's a mirrorless meaning LiveView meaning when it focuses it's actually in focus

That's one way of looking at it. The flip side is to love the detail of control you have with this method. It works great out of the box, but when you adjust like this you're moving that quality into the excellent range.

Yes, geeks adjust things literally, the non-geeks light incense, and chant things. Geeks are more successful in these kinds of things.

True, but that's also why the process is to go through the images and fine tune it based on what you're seeing through the lens. A tape measure of any flavor will get you in the ballpark, but it must be fine tuned for sure.

Yes, Agreed, tethered would help. Decided to roll with it though as I didn't have a long enough USB cord. The 300% helped me see the chromatic aberrations better since that's what I was using to help me fine tune my determination of what was in focus or not.

You might be right, except both Canon and Nikon have focus issues as well. Why do you think the bodies have focus adjustment features?

Not!

Yeah except some of us don’t have several THOUSANDS for brand name primes!!