Lens Focus Calibration Tool Alignment Ruler Folding Card(Pack of 6)

Dirt cheap but perfectly functional. Allowed me to get my 24-70 and 70-200 dialed in and cured for separate back and front focusing issues at close up and further zooms. Also allowed me to demonstrate just how prone to purple fringing my 85mm F1.2 is.How to use: Set your camera and lens up with the lens set to its widest aperture. If it's a zoom, set it first to widest angle (for a 70-200, this would be at 70mm), and snap a pic focusing on the central, vertical target card with the circles and QR code on it. Take that photo into your editing software and look at the checker stripe pattern that goes up the longest face of the triangular shape. Look to see where on that scale the image is best in focus. On my sample image, which is for a Canon F1.8 mk II at 50mm, you can see that it is in focus around the Zero mark, which means this lens does not need any microadjustment as there is no back or front focusing going on. If this is not the case and it seems to be in focus in front or behind the zero point, take a guess at the amount of adjustment needed, take another snap with the camera, re-import and see what has changed. If your lens is now further out of focus, make your change back the other way, and rinse and repeat. If you are adjusting a zoom lens, once you have the widest angle calibrated, zoom all the way and make adjustments for that setting.Can't go wrong for the price, plus you get a handful of them for the price, so you don't have to worry too much about how you treat them.

This item is inexpensive, well-designed, and easy to use. The one shortcoming is that it’s small, which means that you’ll likely be doing your focus calibration over a far shorter distance than you would normally shoot with a given lens. You really need to fill at least half the frame with this target to avoid pixelation and to really see the depth of field, and that means a distance of a foot or less for a wide angle lens, four or five feet for a stronger telephoto lens. I don’t know how much focus calibration is distance-dependent, so this might or might not matter.

I'm a photographer and photography instructor working in a high-end photography store, and I use this to test focus my own as well as customers' cameras and lenses. It works great, especially at this price. It comes flat and folds up cleverly into the form that you see here. The card material isn't especially heavy, probably similar to a take-out food box, but it's good enough because you don't really handle it much.There's no instructions, but hey, if you need instructions maybe you shouldn't be using this. Just make sure the back of the camera is parallel to the vertical panel, lens perpendicular to it, shoot at wide-open aperture. The zero on the rulers should be in sharp focus, fading in front and behind it. If the zero is out-of-focus, then you're either front focusing or back focusing. Make adjustments to correct either situation if your camera has that feature. The 6-pack means I can carry one in each of my camera bags, plus have one at home and one at the office.

Purchased to calibrate a couple of Sigma lenses with the usb dock. Worked perfectly!

Good buy.

Six for 7 bucks. The only problem with this product is the ship time, but I was told at time of shipping how long it would take (I amjust impatient). The product is what it claims to be...made from heavy-stock paper, it easily folds into position. The images are accurate. Plus, you get six of them. If you don't know how to use it, then either read up or skip this product. But for the price and what you get, it is a time saver. Your camera needs to have the AF micro focus adjust feature. If it doesn't, all you can do is determine if your AF system (camera and lens combination) is off or not (if it is off then you need to send them in for calibration, but if you have AFMFA you can tweak it yourself). Well done.

Small. Small. The target Only 3" front of the focusing point and 3" behind. If you step back to12 feet or more for a longer lens, just not enough length of the target. If you try wide angle lens, it is a little bit worse. I tried just a simple tape measure in an angle like 6" front 6" behind the target works a little better. Actually I set up 3 tape measures, right left and the center, because some lens at the edge is different than in the center, focusing wise. (Sharpness of the lens itself in the corners is not generally expected as sharp as in the center of course, but that would be a different issue.)It is an OK product. Wish would be made from a 11" long paper, that wide enough to bend the sides.

All of my camera gear was stolen last year on holiday so I've been rebuilding my photo kit. I started with a full-frame Nikon and bought only 'better' prosumer-grade lenses but was disappointed that my shots were not very sharp. After treading about AF Tuning, I bought this Lens Focus Calibration Tool. What a difference! This tool is not as sophisticated as some of the others but it does the job at a fraction of the cost.