--- product_id: 274226249 title: "28X18cm Lens Focus Calibration Tool Alignment Ruler Folding Card (pack of 2)" brand: "dslrkit" price: "£18.62" currency: GBP in_stock: true category: "Dslrkit" url: https://www.desertcart.co.uk/products/274226249-28x18cm-lens-focus-calibration-tool-alignment-ruler-folding-card-pack store_origin: GB region: United Kingdom --- # 28X18cm Lens Focus Calibration Tool Alignment Ruler Folding Card (pack of 2) **Brand:** dslrkit **Price:** £18.62 **Availability:** ✅ In Stock ## Quick Answers - **What is this?** 28X18cm Lens Focus Calibration Tool Alignment Ruler Folding Card (pack of 2) by dslrkit - **How much does it cost?** £18.62 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.co.uk](https://www.desertcart.co.uk/products/274226249-28x18cm-lens-focus-calibration-tool-alignment-ruler-folding-card-pack) ## Best For - dslrkit enthusiasts ## Why This Product - Trusted dslrkit brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Description Instruction This compact ruler allows you to determine if your lens is auto-focusing accurately as it should. It is an essential tool that is particularly useful when shooting with a shallow depth of field, where focusing should ideally be "spot on". You can use this ruler to determine how "off" the focusing is for a particular camera / lens combination and, on supported cameras, adjust the camera's auto-focus settings to resolve this. On Nikon cameras, this feature is known as "AF Fine Tune". On Canon and Sony cameras, it's known as "AF Micro Adjustment". Please refer to your camera's instructions manual to see if this feature is present. Size:28.1*18cm Package Included: Lens Focus Calibration Card X2 Usage 1. Set up the ruler. 2. Ensure both the camera and ruler are level, exactly perpendicular and at the same height. It is best to mount the camera on a tripod to do this. 3. Set the lens to the widest aperture to obtain the shallowest depth of field. This will make it easier to determine if your lens is focusing accurately. Auto-focus on the crosshair at the center of the ruler, then take a photo. 4. Inspect the photo to see if focusing is accurate. It is recommended that you do this on a computer since you will be able to see better on a bigger screen. If focusing is accurate, the '0' on the ruler should be the sharpest point on the image and the other numbers get blurrier as you move away from the 0. 5. If any number above the 0 is clearer, then your lens is backfocusing. Otherwise, if any number below the 0 is clearer, then your lens is front focusing. In either case, you would have to set the auto-focus micro-adjustment parameters on your camera body until you are able to obtain a picture that is sharpest at the '0' on the ruler. ## Features - This compact ruler allows you to determine if your lens is auto-focusing accurately as it should. It is an essential tool that is particularly useful when shooting with a shallow depth of field, where focusing should ideally be "spot on". - You can use this ruler to determine how "off" the focusing is for a particular camera / lens combination and, on supported cameras, adjust the camera's auto-focus settings to resolve this - On Nikon cameras, this feature is known as "AF Fine Tune". On Canon and Sony cameras, it's known as "AF Micro Adjustment". Please refer to your camera's instructions manual to see if this feature is present. - Size:28.1*18cm - Package Included: Lens Focus Calibration Card X 2 ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B07B5ZHF2P | | ASIN | B07B5ZHF2P | | Brand Name | DSLRKIT | | Color | black and white | | Customer Reviews | 4.4 4.4 out of 5 stars (155) | | Customer reviews | 4.4 4.4 out of 5 stars (155) | | Date First Available | 5 April 2018 | | Is Discontinued By Manufacturer | No | | Item Dimensions L x W | 28.1L x 18W centimeters | | Item Weight | 0.15 Pounds | | Item model number | LFCT2-L | | Manufacturer | DSLRKIT | | Manufacturer | DSLRKIT | | Material Type | Plastic | | Model | LFCT2-L | | Part Number | LFCT2-L | | Product Dimensions | 28.1 x 18 x 0.03 cm; 68.04 g | | Style Name | Compact | ## Product Details - **Brand:** DSLRKIT - **Colour:** black and white - **Material:** Plastic - **Product dimensions:** 28.1L x 18W centimeters - **Style:** Compact ## Images ![28X18cm Lens Focus Calibration Tool Alignment Ruler Folding Card (pack of 2) - Image 1](https://m.media-amazon.com/images/I/71CFDKSpd4L.jpg) ![28X18cm Lens Focus Calibration Tool Alignment Ruler Folding Card (pack of 2) - Image 2](https://m.media-amazon.com/images/I/81PNqOTqtZL.jpg) ![28X18cm Lens Focus Calibration Tool Alignment Ruler Folding Card (pack of 2) - Image 3](https://m.media-amazon.com/images/I/711atAeVgRL.jpg) ## Questions & Answers **Q: How far away should the lens be away from the card?** A: It really depends on the focal length of the lens. You want to try to fill the frame as much as possible with a photo of the card. **Q: What do you focus on to calibrate your lens?** A: Focus on the center target. The plane at which the side graphics are sharp will indicate front or back focus, relative to the center target. Suggest that you look at Youtube videos specific to autofocus calibration - a wealth of information there! ## Frequently Bought Together - DSLRKIT 28X18cm Lens Focus Calibration Tool Alignment Ruler Folding Card (pack of 2) - SanDisk 128GB Extreme PRO SDXC card, SD Card, V30 Memory Card, 4K UHD, up to 200 MB/s, SanDisk QuickFlow Technology, RescuePro Deluxe Data Recovery Software, UHS-I, Class 10, U3, V30 - Tamron Tap-In Console for Nikon Lenses - Black --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.co.uk/products/274226249-28x18cm-lens-focus-calibration-tool-alignment-ruler-folding-card-pack](https://www.desertcart.co.uk/products/274226249-28x18cm-lens-focus-calibration-tool-alignment-ruler-folding-card-pack) --- *Product available on Desertcart United Kingdom* *Store origin: GB* *Last updated: 2026-05-15*