Having looked through the various user manuals associated with the subject software there is very little information that helps to inform a user just learning about digital image processing what's being done. As best I can tell lens correction is something that only applies to the raw (i.e., as yet undeveloped) data. DPP4 has a tab in the editor called "Perform image lens correction". With that tab selected there is a tool called "Digital Lens Optimizer" that appears to depend on having access to data specific to the lens in question. I was able to exercise the control that finds the data and turns the "Lens Data" indicator from "No" to "Yes". Now what? The controls for the various tools are pretty straightforward but what is supposed to happen when they are used is not described? In that, what to look for? So far I've played with them a bit but cannot say that I've noticed any affect.Moving on to the EOS Utility, it appears as though it can be used to either add or remove lens correction data to the camera. Apparently the camera is preloaded with data for some lenses but, depending on the lens/es being used, it may be necessary to add data for the lens/es being used. I presume that removing data for unused lens/es might be necessary because of capacity restrictions but that is only a guess. I didn't notice anything in the user manuals about this idea. Apparently there are some complications (i.e., differences) based on the kind of camera/s being used. The user manuals refer to "Lens aberration correction data" which appears to be applicable for all cameras. Then there is also something called "DLO" with no mention of what that term (e.g., ? acronym) means. Another guess is that it might be "Digital Lens Optimizer", which in this case may only apply to certain cameras.Insofar as this lens specific data is only used when processing raw data, I'm also guessing that it needs to be present in the camera if it is to be used by the camera when producing images in .jpg format. Another guess is that this lens specific data that is loaded into the camera has no affect on the raw files produced by the camera. Since an idea that I've had up to now is that DPP4 is able to produce a .jpg file equivalent to what the camera can produce without the need for any editing on the users part, I'm now pretty confused. In that, when initially installed DPP4 seems to have no lens correction data until it is added (e.g., ? downloaded) by the user. Since, it appears that my lenses are among those that have no lens correction data pre-installed in the camera I'm thinking I might be lucky enough to be getting equivalent .jpg images from either DPP4 processing a raw file or the camera produced .jpg file but what about all those lenses that appear to be pre-installed in the camera?Finally, with all of that said, my present method is to produce raw files in the camera and then develop them myself using software like DPP4 as well as other, primarily open source, software such as GIMP and Rawtherapee. I'm thinking it should not matter in this case what lens correction data is present in the camera. In that, one only needs to worry about having the correct lens specific data installed in the camera if they want it used by the camera when producing .jpg files. Is this notion valid?My apologies for the number of words but hope my concerns are clear. Where I've often mentioned my need to guess it would be great if those of you who know for sure could straighten me out.
*3 To use this function with compatible lenses other than the SIGMA 100-400mm F5-6.3 DG DN OS Contemporary and the SIGMA 85mm F1.4 DG DN Art, it is necessary to update the firmware corresponding to the focus ring adjustment function.
Canon Lens Adjustment Software
I have already installed your software and the Auto Focus change is incredible. I have installed the focus data from my camera body to my son's body to test and the result is total. It has improved completely and already only has a slight backfocus that is correctable from the micro-adjustment menu. ...
I chose a lens that is perfect for this software. This copy of the 35mm f/1.4 is perfect on my Canon 6D at close and intermediate distances, but at long distances it backfocuses badly. I can do a microfocus adjustment to correct long-distance focus, but then the lens is frontfocusing at near distances. Without the Sigma dock and software, the only option was a trip to the factory service center to change the lens parameters.
Total elapsed time for firmware update, focus checks, focus adjustments, and final check was just about 10 minutes. Obviously a zoom lens, which can be adjusted both at different focal lengths for different focusing distances at each focal length, will take longer.
For the even slightly gear-head amongst us, this is an awesome tool, giving us the ability to fine-tune autofocus adjustment much more completely than simple camera microfocus adjustment. At $59, I consider it an amazing bargain for anyone who owns one of the Sigma Art, Contemporary, or Sports lenses (it does not work on older lenses).
Remember that you may need to calibrate your lenses again after buying a new camera. The new camera is unfamiliar with the optical lens adjustments you made (and it might not be spot-on). So it would be best if you calibrated them again.
In either case, you need to correct your lens for sharp focus. You do this using the autofocus micro-adjustment parameters on your camera body. Adjust until you can get the sharpest picture at zero on the ruler.
Initially, distortion correction data was stored on the camera for some lenses, and if you wanted to use other lenses the optical correction data for those lenses had to be downloaded via the EOS Utility software and registered to the camera. However, since the introduction of the EOS 5DS and the EF 11-24mm f/4L USM lens in 2015, this data has been stored in the lens itself. This means that the camera can access the lens data and apply it when processing JPEGs in-camera. If you're shooting RAW, however, you will still need to download the appropriate lens profile on your computer.
There are a number of free and commercial tools for calibrating / fine tuning lenses. I have tried a number of different methods and I have identified which ones work and which ones are unreliable. One of the free/DYI methods involves printing a bunch of lines on a piece of paper, then setting up your camera at a 45 degree angle and taking pictures. I started out with this method about 4 years ago and quickly found it to be very unreliable. With high resolution cameras like D800, using this method can yield unpredictable results, since fine tuning has to be very precise to get accurate results. Another free/DYI method is to use your monitor screen with a test chart image, which again can be problematic for proper testing. The second method is to get a commercial tool like LensAlign by Michael Tapes Design, which is what I have been doing for the last 3+ years and find it to be much more reliable and precise than the free method. The third method is to use an automated/semi automated software calibration tool that can save you time and possibly yield better results. Here is a quick summary with pros and cons of each method:
The process with automated lens calibration is a little different. Currently, Reikan FoCal seems to be the leader in automated calibration software, which not only performs automated/semi-automated calibration (depending on what camera is used/supported), but also comes with pretty advanced reporting capabilities and testing of each individual focus point. The software became increasingly popular on Nikon cameras lately, thanks to the whole Nikon D800 Asymmetric Focus Fiasco, because it can clearly show which focus points are accurate and which ones are not, as shown in the below image:
As you can see from this article, calibration is a complex topic. Unfortunately, a number of photographers and online resources blindly recommend taking different approaches to lens calibration without fully understanding how autofocus system works, which leads to more frustration and unhappiness from end users. In my opinion, it is important to know and understand all the details of the process, including possible outcomes before deciding to touch this feature. Despite all challenges, I still highly recommend to play with the AF adjustment feature on your camera and learn how to properly calibrate your camera gear. At the end of the day, you want to get the best out of your equipment.
I had concerns about self lens calibration when using just a tripod and shooting a target. There were inconsistencies in accuracy and repeatability. So I thought what I could do to eliminate the chances for error before making adjustments. A few things I thought of in order to calibrate a lens correctly: 1. The camera sensor must be parallel to the target. If off in pitch & yaw there would be errors in calibration in the fore & aft. 2. The lens z-axis must be perpendicular to the target.
Focus calibration is an adjustment to correct front focus or back focus. This is where the sharp area of your image falls just in front of, or just behind, where you intended to focus. Calibration tells the camera that for a specific lens the focus should be pushed back or forwards a little to compensate for this inaccuracy. Canon calls this setting AF micro adjustment while Nikon calls it AF fine tune. We test each of the lenses you supply with each of your camera bodies at every focus adjustment position to identify the best focus position for each camera and lens combination.
Also, some mirrorless cameras will have the option to do AF Micro adjustments (i.e. the Sony A7 series) to correct for combating lens element displacement issues or to get better results from lens adapters like the Metabones or the Sigma MC-11 adapters. 2ff7e9595c
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