Recording of meetinghttps://my.adobeconnect.com/p20owude3zk/

Adobe Lens Profile CreatorMac - http://www.adobe.com/support/downloads/detail.jsp?ftpID=5489Win - http://www.adobe.com/support/downloads/detail.jsp?ftpID=5490User Guide - http://wwwimages.adobe.com/www.adobe.com/content/dam/Adobe/en/products/photoshop/pdfs/lensprofile_creator_userguide.pdf

Adobe Lens Profile DownloaderMac - http://www.adobe.com/support/downloads/detail.jsp?ftpID=5491Win - http://www.adobe.com/support/downloads/detail.jsp?ftpID=5492User Guide - http://wwwimages.adobe.com/www.adobe.com/content/dam/Adobe/en/products/photoshop/pdfs/lensprofile_creator_userguide.pdf

Adobe DNG Profile EditorMac - http://www.adobe.com/support/downloads/detail.jsp?ftpID=5493Win - http://www.adobe.com/support/downloads/detail.jsp?ftpID=5494User Guide - http://wwwimages.adobe.com/www.adobe.com/content/dam/Adobe/en/products/photoshop/pdfs/cs6/DNGProfile_EditorDocumentation.pdf

Adobe DNG ConverterMac - http://www.adobe.com/support/downloads/detail.jsp?ftpID=5645Win - http://www.adobe.com/support/downloads/detail.jsp?ftpID=5646

Shooting the Calibration Images

You need to shoot grid charts for geometry and vignette correction. The grid charts are available as pdf files with the Adobe Lens Profile Creator installer.

Set up:

Make sure that the camera is running the latest firmware.Set the camera to its base ISO.Set the camera to Manual so that exposure doesn't change shot to shot. Set the aperture to f/11, and the shutter speed to whatever speed you need to get a well exposed shot of the chart.Set the camera to record raw (or JPEG, or both if that's what you want - profiles are raw or JPEG specific - a profile made with raws won't work with JPEGs, and vice versa).

Set white balance to Auto.Set the focus to manual.If the lens includes optical stabilization, turn it off.Remove any filters from the lens (unless you always shoot with that filter on, and want the profile to account for the filter).Make sure the lens is clean (front and back elements, and filter if any).If the camera includes any sort of in-camera image processing, turn it off (no noise reduction, no "looks," etc.).If the lens you are profiling is a full frame lens, you must use a full frame camera. Likewise, if the lens is an APS-C lens, you must use an APS-C camera. Or, put another way, use a camera for which the lens was intended.Start with the lens at one end of its focal length range (for example, the wide end).Place the camera on a tripod.Place a grid chart on an easel, or tape it to a wall, or whatever, and light it evenly. I suggest shooting outside to get even lighting. It is very important that the chart be evenly lit, and that it be absolutely flat.The charts are available as PDFs included with the Adobe Lens Profile Creator download.

1. Place the camera as close to the chart as it can be placed, based on the minimum focus distance of the lens. (Make sure that the camera is not casting a shadow on the chart.)2. Pick a chart size such that the grid occupies one quarter to one half of the frame. (Note that sometimes, depending on the focal length, and minimum focus distance, even the smallest chart may fill more than half the frame. In that case, move the camera back as far as you need to so that the grid occupies no more than about half of the frame.)3. Center the grid in the frame and take a shot.4. Tilt down and align the top of the grid with the top center of the frame, and take a second shot.5. Tilt up and align the bottom of the grid with the bottom center of the frame, and take a third shot.6. Move the camera roughly 15 degrees to the left of center, align the left edge of the grid with the left center of the frame, and take a forth shot.7. Tilt down and align the top and left edges of the grid with the top and left edges of the frame, and take a fifth shot.8. Tilt up and align the bottom and left edges of the grid with the bottom and left edges of the frame, and take a sixth shot.9. Move the camera to roughly 15 degrees right of center, and repeat steps 6, 7, and 8 with the right edge of the frame.

The nine shots you will have after the steps above are an "image set." The idea is that between all the shots in an image set combined, the whole frame is covered by the grid. Your nine shots should look something like this:

10. Repeat steps 1-9 for each marked focal length on the lens. A prime lens obviously has only one focal length. Zoom lenses typically have between five and seven marked focal lengths (from this, it is easy to extrapolate that profiling a zoom lens is going to take you five to seven times longer than a prime lens).11. Move the camera away from the chart to 2X minimum focus distance and repeat steps 2-10.12. Move the camera away from the chart to as close to "infinity" as you can practically get and repeat steps 2-10. The "infinity" distance that I typically use is about 25-30 feet, but a very wide lens may require you to be closer, and a very long lens might require you to be farther away.13. Now for the bad news. I didn't go over this in the presentation, but if you want the vignette correction to be reasonably accurate, then in addition to shooting at f/11 as described, you also need to repeat steps 1-12 at the lens's widest aperture. If you

only shoot at f/11 when generating the profile, then vignetting will likely be under-corrected when shooting at wider apertures.

Keep in mind the following:

Not all the shots can be taken from the same camera position. The camera must be moved as described, or the Adobe Lens Profile Creator (ALPC) won't have enough info to calculate the distortion.In some cases, depending on focal length, focus distance, and grid size, you may not be able to get coverage of the whole frame in only nine shots. In these cases you might need 15 shots (three columns of five) or even 25 shots (five columns of five).The entire grid must be kept within the frame. No part of the grid can be cut off by the frame edge in any shot. When shooting shots where the grid is aligned with the edge of the frame, get the grid as close to the edge as you can, consistent with not cutting any of it off.In the resulting pictures, the smallest individual square of the grid should be at least 20 pixels wide/tall, or the ALPC won't be able to accurately detect the grid (In practice, I've gotten away with smaller, but 20 is safe.)The focus must not be changed within an image set! Make sure that you have set the focus to manual. Focus crisply before taking the first shot, and then do not change the focus again within the image set! The camera does not need to stay exactly the same distance away from the chart for each picture within an image set, it just needs to be consistent enough that the grid squares stay in focus well enough that the ALPC can recognize them. This can be tricky when shooting off angle at the minimum focus distance, as a limited depth of field can mean that not all of the chart is in focus at the same time. Shooting at f/11 will minimize this problem in most cases, but it can be tricky when shooting wide open.Make sure that in at least one of the shots in an image set, you can see the info that is printed on the chart below the grid (the grid dimensions and point size). Shoot an extra shot if you have to. This is just for your own reference, as you'll need this info later in the ALPC.

Organizing the files:

Before opening any of your calibration images in ALPC, they should be arranged on disc in a specific hierarchy:

Lens Name > Focal Length > Focus Distance

Like this:

Once your files are arranged on disc, they must be converted to DNG using the Adobe DNG converter before opening them in ALPC. You can convert the entire hierarchy by dragging the "Lens Name" folder onto DNG converter. In DNG converter, select "Include images contained within subfolders" in section 1, and in section 2, choose "Save in Same Location." This will preserve the hierarchy. Leave other settings at default, and click "Convert." Once the conversion has finished, you're ready to make your ALPC project.

Making the ALPC project:

1. Launch the ALPC. A new project will be created automatically, or you can go to File>New Project.2. Go to Adobe Lens Profile Creator>Preferences.3. Check "Do not show warning messages."4. Uncheck "Always prompt the save profile dialog."5. Select a profile location of your choosing.6. Uncheck "Prompt for confirmation to input ruler measurement."7. Click OK.8. Go to File>Add Images to Project…9. Each image set must be selected and added individually. So, in the example of the Canon 28-135 above, you would navigate to Canon EF 28-135mm f3.5-5.6 IS USM>Focal Length 28>Focal Distance 1. You would select all in that folder, and click "Open."10. Then repeat with each focus distance of each focal length.11. When you have imported all the chart shots, the "Profiles" section will show the

lens name, and under it, each focal length will be listed. (If you chose to shoot at multiple apertures, then each focal length/aperture combination will be listed.):

:

If you select a given focal length (focal length 28.0 mm is selected in the screenshot above), then in the "Images" section you'll see each focus distance group for that focal length. You should have three focus distance groups for each focal length.:

:

12. At the top of the "Profiles" section, check the top level checkbox next to the lens name, so that all sub-checkboxes become selected as well.13. At the top of the "Profiles" section, select the lens name. (When the lens name is selected, changes made to settings apply to all focus distances in all focal lengths.

If you select a specific focal length under the camera name, changes to settings apply to all focus distances in that focal length only. If you also select a specific focus distance in the "Images" section, then changes made to settings apply only to that focus distance in that focal length.)14. Select the "Calibration" tab.15. In the "Lens" section, select "Rectilinear" or "Fisheye," as appropriate. (The vast majority of lenses are rectilinear.)16. In the "Model" section, uncheck "Chromatic Aberration Model" because Lightroom will just ignore this data if it's there, so there's no point in generating it. Make sure that "Geometric Distortion Model" is checked, and you can check "Vignetting Model" or not, depending on what you want.17. Click the "Advanced" tab.18. In the "Rectilinear Lens Model" section (or the "Fisheye Lens Model" section, as appropriate), select "Three-Parameter Radial Distortion."19. In the "Principal Point" section, select "Best Estimate" for any focal lengths that are shorter than 50mm equivalent, and select "Fixed Center Location" for any focal lengths that are 50mm equivalent or longer. Unlike the other settings discussed so far, this is one that you may not want to set globally for a lens (some of the focal lengths of a single zoom lens might be shorter than 50mm, some longer). If necessary, specify this setting for each focal length individually as described in step 13 above.20. Leave the other "Advanced" settings at their defaults, and click the "Calibration" tab again.21. In the "Profiles" section, select the first focal length (28.0 mm, in our example of the Canon 28-135).22. In the "Images" section, select "Focus Distance Group - 1."23. In the "Checkerboard Info" section, enter the grid info. The "Version (Row x Column)" and "Print Dimensions" info is all written on each chart under the grid. If you followed the instructions in the "Shooting chart shots" section above, this information will be visible in at least one of your calibration shots for each image set, you can just go ahead and enter it verbatim.24. The "Screen Dimension (Pixels)" value can be entered using the measuring tool. Select the measuring tool, located on the toolbar underneath the image area, and click and drag on the image to measure the length of a side of one of the grid squares, in pixels. The measured value will automatically be entered in the "Screen Dimension (Pixels)" field. A couple of notes on this:

You should measure the shortest side of the smallest square in the image set. Usually this is the width of the square furthest from the camera in one of your off-angle shots.Measuring the side of a small square can be easier if you magnify the image, with the magnifying glass, or the magnification pop-up menu, both on the

toolbar beneath the image area.You don't have to be brain-surgery-precise about selecting the absolute smallest square. Get close, and everything will work out fine.

25. Repeat steps 23-24 for each of the focus distance groups in each of the focal lengths.26. Save the project.27. Make sure that you check the top level checkbox (i.e., next to the lens name in the "Profiles" panel), and click the "Generate Profiles" button.

If it's a zoom lens with a lot of focal lengths, go out to lunch. And possibly dinner. If it's a prime lens, a coffee break will suffice. A long coffee break.

Making sure it worked:

1. There should now be a profile saved in the location you specified in step 5 above.2. In the "Images" section of the ALPC, if any file has an exclamation mark next to it, that means grid detection failed for that image. If grid detection failed for one or two images out of several hundred, don't worry about it. But if there are a lot of failures, especially if there are several failures within one image set, you should reshoot the image set or sets in question, after determining the reason for the failures.3. How do you determine the reason for the failures? Any shot for which grid detection failed will have a red dot at every grid intersection point that the ALPC was able to detect. Grid intersection points which the ALPC was not able to detect will be blank. Looking at which specific points failed can often tell you what went wrong. Usually part of the grid is out of focus, but maybe there's light glaring off of it, making a black square look too white, or maybe there's a scuff on the chart, or maybe part of the grid got cut off. (A handy tip: do this check BEFORE quitting the ALPC or closing the project. If you close and reopen a project, all those helpful red dots will be gone, and you'll need to run the project (or relevant portion of the project) again to get them back.)4. If an image set fails spectacularly, you might have entered the wrong information in the "Checkerboard Info" section, so that's something to double check.

An image set with no errors:

An image set with one error, not so bad:

Probably want to reshoot:

Definitely time to head back to the studio:

Here's a magnified section of an image that failed:

You can see that the intersections which were detected are marked with red dots. The two intersections which were not detected are on either side of a black square which is marred by a white mark. A black sharpie and a quick reshoot fixed this problem. Note that if an image or images fail, you don't need to reshoot everything, you only need to reshoot the image set in question. You also don't need to regenerate the whole profile, you can regenerate the profile for just that image set, and merge the results with the rest of the profile that you made previously.

Tips and Tricks

Use Lightroom to shoot tethered! Most of the lenses you'll be profiling will be for Nikon or Canon SLRs, and many Nikon and Canon SLRs can be used with tethering in Lightroom. There are a lot of advantages to shooting tethered, vs. simply recording the images on a camera card and transferring them to a computer later.Using Destination, Session Name, and Shots, you can create the LensName > FocalLength > FocusDistance hierarchy as you shoot, instead of having to manually organize all the photos after the fact.You can immediately check framing, exposure, and focus much better on a computer screen than on the camera's screen.You can immediately verify metadata. This is especially useful for making sure that you actually set the zoom lens to 50mm, rather than 49mm.With all of the photos organized right there in Lightroom, it makes it much easier to keep track of what you've already done and what you have left to do (a serious issue when a single lens can sometimes require 300-400 shots).You can use Lightroom, connected to the camera via USB, as a cable release,

very handy since you often have to shoot long exposures (shooting with little light at base ISO and f/11).If you mess up a shot its easy to delete on the spot (make sure you delete it from disc, rather than just removing it from the Lightroom database).You can also convert to DNG in Lightroom, eliminating the need to use the stand alone DNG converter before running the images through the ALPC.It's not all sunshine, at least not where Nikon is concerned. Nikon cameras cannot use Liveview (see below) when shooting tethered with Lightroom. Also on Nikons, camera settings cannot be changed while a file is in the process of transferring from the camera to Lightroom. Canon cameras do not have either of these problems.