You may have already heard of sample variation or decentered lenses. If you know how it works it will take you less than 5 minutes per lens! In this article we will show you how to easily test your lenses for proper centering. This test was published by the German Gletscherbruch homepage, but as this website is only available in German we decided to write an English version. There’s a fair amount of aliasing towards the center, but that should all be a blur in actual use.This is the most important one: do not send us your shots and ask if we think your lens is okay.Move your camera on the ballhead until your target is in one of the extreme corners of the frame and take the shotĬhimney in upper right corner Chimney in lower left cornerīefore you rate your shots there are a few things to consider.You put your target in the center of the frame and you focus on it.įocus is on the chimney in the center of the frame.electronic first curtain shutter off (if you have a stable tripod).use the widest aperture of your lens (some lenses have very bad corner performance, stop these down until there is visible detail in the corners).Some building far away (chimney, antenna, church tower etc.). Gray Gamma 2.2 is as good as anything.Īnd here’s a really big file (12000×12000 pixels, 200 spokes), for those making a really big target. Since every pixel in the files is either pure black or pure white, it doesn’t matter what grayscale profile you assign. When you open them in Photoshop, you’ll see something like this: If you want bigger targets, scale them using bilinear interpolation. If you want to print on smaller paper, crop the targets, but print at 360 or 300 ppi. To download a file, right-click on the link below, then choose “Save as…”įor optimal results, don’t scale the targets send them to your printer driver at 360 ppi in the case of the Epson files, or 300 ppi for the Canon ones.
There are three stars for Epson printers, which want 360 ppi input images, and three for Canon printers, which take 300 pi images. Updated: Returned to Best Buy and they apologized and took it, no hassle, no drama. I recommend everyone to check their lens, regardless if its a G Master. Pretty unacceptable for a 2200 flagship, 'Pro' lens. All are sized for 16-inch (410 mm) stars. I used the Zeiss-Siemens Star Chart and the lens showed to be decentered slightly.
Below are links to six printable targets.
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