These certainly are not in the same calibre as Canon's extension tubes for the regular EF mount - as the metal seems to be brushed aluminum and they are fairly light in the build quality. I wouldn't trust it to hang a 100-400 off of. Trying it with the M and the 10,16 or the stacked full 47mm tubes with the 18-55mm looked a little comical. The Auto Extension Tube Set for Canon EF/EF-S Mounts and Lenses from Vello consists of 12mm, 20mm, and 36mm tubes with durable metal lens mounts. The extension tubes reduce the minimum focusing distance on your lens and enable you to capture the fine details of an insect or the inside of a flower. The function of the camera and lens is unchanged, and you can combine extension tubes for greater magnification. Canon offers two extension tubes, the EF 12 II and the EF 25 II. Magnification differs by lens, but with the EF12 II and standard zoom lenses, it is approximately 0.3 to 0.5. With the EF 25 II, magnification is 0.7. extension tube question. 02-23-2021 12:20 PM. I need to know the inside diameter of the Canon 12mm extension tube . I want to use the extension tube between my 1.4X III teleconverter and my 100mm 2.8 L macro (which are otherwise non-compatible). I have read where people are using this combo successfully BUT the protruding portion of the Optics-free extension tubes to reduce the minimum focusing distance and turn any lens into a macro lens. Category. Mount. Extension Tube Set DG for Canon EF. Set of 3 extension tubes to enjoy macro photography with your standard lens. Extension Tube Set DG for Canon RF. Extension tube set of two rings (10mm and 16mm) to enjoy macro photography 1. Extension tubes have no optics, so there is little detrimental effect on the optical quality of the lens. There's some potential for loss of IQ, when you use a teleconverter, more with a 2X than a 1.4X or 1.5X. 2. Using the 2X teleconverter will give you more working distance. An extension tube is a non-optical device that increases the distance between the lens and the film. This allows the distance between the lens to focus much closer than normally possible and thus, gave the increased magnifications. The EF 12 tube provides a 12mm extension while the EF 25 version adds just over 25mm of extension. Top 10 Lens Extension Tubes. 1. Canon EF 25 II Extension Tube for EOS Digital Cameras; 2. MEIKE MK-S-AF3A Metal Auto Focus Macro Extension Tube Adapter Ring 3. JJC F Mount Auto Focus Macro Extension Tube Set for 4. Auto Focus Macro Extension Tube Set, Tosuny Metal Auto Focusing 5. Mcoplus Extnp Auto Focus Macro Extension Tube Set Canon EF 25 extension tube Specification The Key Features. Shortens focusing distance of lens; Compatible with digital EF-S, EF, and TS-E lenses; Canon produces tubes in two different lengths - 12mm and 25mm. The EF12 and EF25 tubes come with electrical contacts which allow data transfer between the lens and camera to be maintained. Compare Canon Extension Tube EF 25 II vs Vello Auto Extension Tube Set for Canon EF EF-S Mounts and Lenses V2 Press ‎ ↵ Enter ‎ for Accessibility for blind people who use screen readers Press ‎ ↵ Enter ‎ for Keyboard Navigation h6Ulp.