K&F Concept United Kingdom    Blog >

Enjoy Your Selected Digital Life

Currency: GBP
  • Currency

Log Into Your Account

Account

Order History

Wish List

Register Account

Already have an Account?Log In

  • Shopping Cart

  • Your shopping cart is empty!
  • Favorite

  • Your wish list is empty.

Kentfaith Deals Today Most Wished For Canon Eos R Adapter Ef Kentfaith is committed to creating the ideal Canon Eos R Adapter Ef envisioned by users, redefining the Canon Eos R Adapter Ef experience through exquisite craftsmanship. To meet your most desired perfect choice, enjoy today's promotion, platform subsidies directly reduced by 15% discount!
K&F Concept EOS Lens to EOS R Mount Adapter, Compatible with Canon EOS EF EF-S mount lens and Compatible with Canon EOS R Cameras
Most Wished For
K&F Concept EOS Lens to EOS R Mount Adapter, Compatible with Canon EOS EF EF-S mount lens and Compatible with Canon EOS R Cameras
EOS EF Compatibility EOS R Support Manual Aperture Infinity Focus Metal Construction Light Reflection Prevention Compact Design Precision Fit Elegant Appearance Manual Operation
-This adapter allows users to connect EOS EF EF-S mount lens to EOS R mount cameras. Canon STM series lenses (such as EF 50mm f/1.8 STM, EF 18-135 IS STM) don't work with our adapters.
-As EOS lenses are electronically controlled, most EOS/EF mount lenses do not feature a manual aperture ring, so when used on our EOS-EOS R, which is a full manual operation adapter ring, the aperture could not be transferred to the camera, it will stop down to its smallest f/stop by default
-Anodized Aluminum and Heavy Grade Brass Construction, matting varnish inside to avoid light reflection.
- There are two types of FD mounts, the installation way and aperture control way are different, please contact our professional after sales team for help if you encounter this kind of issue.
- Manual adapter, auto diaphragm/auto-focus is not allowed.
Original Price £55.99
Discounted Price £41.99
-
Deal Discount £6.30
=
Final Payment £35.69
Total Save £20.30
Updated MD to NEX Adapter, Manual Lens Mount Adapter Compatible with Minolta MD MC Mount Lens and Compatible with Sony E NEX Mount Camera Body
Most Wished For
Updated MD to NEX Adapter, Manual Lens Mount Adapter Compatible with Minolta MD MC Mount Lens and Compatible with Sony E NEX Mount Camera Body
Manual compatibility Infinity focus All-metal design Anodized aluminum Cost-saving Precision fit Diaphragm control Brass construction Prime lens use E-mount support
- Manual adapter, no electrical contacts in the adapter ring and cannot achieve auto diaphragm or auto-focus, please be careful.
- This adapter helps to connect Minolta MD/MC mount lens to Sony E-mount mirrorless cameras.
- Designed to compatible with Sony Alpha E-mount Cameras: Sony Alpha α7, α7R, α7S, α7 II, α7R II, α7S II Sony Alpha α3000, α5000, α6000, α6300, α6500,α3500, α5100, αQX1, PXW-FS7 Sony NEX-3, NEX-5, NEX-C3, NEX-5N, NEX-7, NEX-F3, NEX-5R, NEX-5T ,NEX-6, NEX-F3, NEX-3N Sony NEX-VG10, NEX-VG20, NEX-VG30, NEX-VG900, NEX-FS100, NEX-FS700, NEX-EA50 etc.
- Infinity focus function is allowed, please adjust manually when first use.
- Upgrade all-metal design and anodized aluminum construction. Any question about products please contact us freely.
Original Price £41.99
Discounted Price £32.99
-
Deal Discount £4.95
=
Final Payment £28.04
Total Save £13.95
K&F Concept Pentax K Lens Mount to Sony E Camera Body Adapter Ring, matte lacquer, PK-E FIT ART
Most Wished For
K&F Concept Pentax K Lens Mount to Sony E Camera Body Adapter Ring, matte lacquer, PK-E FIT ART
Pentax-Sony compatibility Manual control High durability Easy alignment Tight fit Infinity focus Matte finish Precision manufacturing Vignetting correction Lens renewal
-Pentax K series and AF series lens to Sony E series body adapter ring.
-High-quality copper aluminum alloy precision manufacturing, durable, comfortable and smooth disassembly and assembly.
-The full manual control, the shape is placed in a stable, not easy to slip, more secure.
-Red dot logo, precise alignment, easy to install and remove.
-Joint ring with the bayonet combination is tight and smooth, no loose phenomenon.
Original Price £38.99
Discounted Price £38.99
-
Deal Discount £5.85
=
Final Payment £33.14
Total Save £5.85
4.5" Suction Cup Camera Mount with Double Ball Head Magic Arm, Mobile Phone Clamp, Gopro Adapter Accessories, 3/8" to 1/4" Adapter Screw, MS45
Most Wished For
4.5" Suction Cup Camera Mount with Double Ball Head Magic Arm, Mobile Phone Clamp, Gopro Adapter Accessories, 3/8" to 1/4" Adapter Screw, MS45
Strong Adsorption Vacuum Pump Multi-angle Adjustment Double Ball Head Widely Compatible Dust-proof Design Warning Line Filter Cotton Gopro Adapter Smooth Surfaces
-【Strong Adsorption】The vacuum pump design can safely and securely fix various small devices or equipment on smooth surfaces.
-【Widely Compatible】The suction cup has multiple expansion interfaces, with 1/4" and 3/8" screw holes and positioning holes. The top of the pea pod has 1/4" + telescopic positioning pins.
-【Multi-angle Adjustment】The pea pod adopts a double ball head design, which can achieve multi-angle free rotation adjustment. Upper and lower top 1/4" + telescopic positioning pin design.
-【Warning Sign】The vacuum suction cup is marked with a warning line at the vacuum pump. When using, press the vacuum pump until the warning line disappears.
-【Dust-proof Design】Equipped with filter cotton and dust cover for better protection.
Original Price £49.99
Discounted Price £45.99
-
Deal Discount £6.90
=
Final Payment £39.09
Total Save £10.90
K&F Concept Canon EW53 bayonet hood with a vacuum cleaning cloth *1, suitable for EF-M 15-45 mm f/3.5-6.3 IS STM; RF-S 18-45 mm f/4.5-6.3 IS STM and other lenses
Most Wished For
K&F Concept Canon EW53 bayonet hood with a vacuum cleaning cloth *1, suitable for EF-M 15-45 mm f/3.5-6.3 IS STM; RF-S 18-45 mm f/4.5-6.3 IS STM and other lenses
Canon compatible Image quality Glare prevention Lens protection Durable material Snap-on design Lightweight build Reversible use Portable design Easy installation
-Compatible: Compatible with Canon EF-M 15-45mm f/3.5-6.3 is STM & RF-S 18-45mm f/4.5-6.3 is STM Lens, Replacement for EW-53 Lens Hood.
-Elevate Image Quality: The K&F Concept Lens Hood can effectively prevent stray light from affecting the image and improve image quality. Preventing the entry of non-imaging light and avoiding glare in backlight, side light, or flash photography. Avoiding the surrounding scattered light into the lens in downlight and sidelight photography. Avoid the surrounding interference light into the lens in light photography or night photography
-Protect Lens: The K&F Concept lens hood is made of high-quality composite material, durable, and wear-resistant, can effectively protect the lens by preventing fingers from accidentally touching the lens surface, preventing dust, water droplets, and other foreign objects from entering the lens, and protect the lens from accidental collisions.
-Snap-On Design: Quick install and remove, 49mm lens cap, UV and other effect filters can still be attached after installation.
-Portable: Made of premium ABS material, it's lightweight and reversible, easy to carry.
Original Price £9.99
Discounted Price £9.99
-
Deal Discount £1.50
=
Final Payment £8.49
Total Save £1.50
62mm-82mm Magnetic Lens Filter Adapter Ring
Most Wished For
62mm-82mm Magnetic Lens Filter Adapter Ring
Magnetic adapter Quick installation Impact resistant Aviation-grade aluminum Reflection prevention Anodized black Stable suction Larger filter compatibility High strength K&F compatible
-Larger filters can be adapted to lenses with smaller thread sizes
-Made of aviation-grade aluminum alloy with high strength and impact resistance.
-The surface process adopts anodized black treatment to prevent reflection during shooting
-Stable suction, quick installation and removal. Suitable for all K&F Concept magnetic lens filter.
-Notice: The 82mm magnetic adapter ring can only be connected to the 82mm magnetic filter. Not suitable for non-magnetic lens filters.
Original Price £24.99
Discounted Price £24.99
-
Deal Discount £3.75
=
Final Payment £21.24
Total Save £3.75
T2 Lenses to Nikon Camera Mount Adapter
Most Wished For
T2 Lenses to Nikon Camera Mount Adapter
T2 mount Nikon compatibility Durable construction Infinity focus Manual operation Wide camera range Brass aluminum Telephoto support Satisfaction guarantee Lens adaptability
-Allow T2 mount lenses used on Nikon DSLR camera body.
-Compatible with Nikon camera includes: Nikon D3000, D300s, D3100, D3200, D3300, D3400, D3s, D3x, D4, D400, D4s, D5, D500, D5000, D5100, D5200, D5300, D5500, D5600, D5s, D6, D600, D610, D700, D7000, D7100, D7200, D750, D7500, D760, D800, D810, D810a, D850, D90 etc.
-Made of brass and aluminum. Stable, precise and durable construction. Manually operated. Infinity focus allowed.
-For heavy medium format lenses, we suggest to use with a telephoto bracket and a tripod to balance its weight when shoot.
-30 Days No Reason Return, 12 months quality guarantee, 100% satisfaction assurance.
Original Price £18.99
Discounted Price £18.99
-
Deal Discount £2.85
=
Final Payment £16.14
Total Save £2.85
Canon FD Lenses to Leica M Camera Mount Adapter
Most Wished For
Canon FD Lenses to Leica M Camera Mount Adapter
Canon FD compatibility Leica M compatible brass aluminum build durable construction infinity focus manual operation telephoto bracket support tripod usage 30-day return 12-month guarantee
-Allow Canon FD FL mount lenses used on Leica M series camera body.
-Compatible with Leica M camera includes: Leica M1, M2, M3, M4, M5, M6, M7, M8, M9, M10, MP, MD, ME etc.
-Made of brass and aluminum. Stable, precise and durable construction. Manually operated. Infinity focus allowed.
-For heavy medium format lenses, we suggest to use with a telephoto bracket and a tripod to balance its weight when shoot.
-30 Days No Reason Return, 12 months quality guarantee, 100% satisfaction assurance.
Original Price £52.99
Discounted Price £38.30
-
Deal Discount £5.75
=
Final Payment £32.56
Total Save £20.44
Adjustable Iris Aperture Diaphragm M30 to M37 Iris Aperture Diaphragm Adapter Optical Diaphragm 1.5-26mm Lens Module Adapter Ring Optics PVS14
Most Wished For
Adjustable Iris Aperture Diaphragm M30 to M37 Iris Aperture Diaphragm Adapter Optical Diaphragm 1.5-26mm Lens Module Adapter Ring Optics PVS14
Adjustable size Precise control Lightweight design Rust resistance Corrosion resistance Durable materials Easy operation Increased flexibility Lens compatibility Cost reduction
-Provides adapter function, adjustable size M30 - M37, 1.5 - 26 mm aperture, allows different sizes of filters to be installed on the lens, increases the applicability and flexibility of the lens, and reduces the purchase cost.
-Provides precise aperture adjustment control to control the amount of light entering, suitable for PVS14 monocular night vision equipment and PVS14 binocular night vision equipment, as well as other 30mm caliber equipment.
-Made of aluminum alloy and stainless steel materials, it ensures the durability of the aperture and the safety of the equipment, preventing damage to expensive photographic equipment.
-Just use the handle to change the aperture diaphragm diameter, which is easy to operate.
-Lightweight, does not add extra weight to the equipment, and has the advantages of high strength, rust resistance and corrosion resistance.
Original Price £30.99
Discounted Price £27.99
-
Deal Discount £4.20
=
Final Payment £23.79
Total Save £7.20
37mm Magnetic Lens Filter Kit GND8+ND8+ND64+ND1000+Magnetic Adapter Ring 5 in 1 Quick Swap System Nano-Xcel Series
Most Wished For
37mm Magnetic Lens Filter Kit GND8+ND8+ND64+ND1000+Magnetic Adapter Ring 5 in 1 Quick Swap System Nano-Xcel Series
5-in-1 Kit Magnetic Swap Light Reduction Silky Effect Multi-Layer Coatings Waterproof Glass Scratch Resistant Dustproof Design Ultra Slim No Vignetting
-【5-in-1 Filters Kit】Combination Way 1. Magnetic Adapter Ring + ND Filter. This filter kit includes GND8+ND8+ND64+ND1000 + Magnetic Basic Ring + Filter Pouch.
-【Light Reduction Effect】The ND8/ND64/ND1000 provides a 3/6/10 stops light reduction effect and fits a partly cloudy day and a bright sunny day. The nd1000 filter can create the silky effect of item movement.
-【1 Second Swap】This magnetic lens filter kit could finish swap in less than one second compared with conventional thread filters. Never miss any wonderful moment.
-【28 Multi-Layer Coatings】All filters are made of imported AGC high-definition premium optical glass, double-side multicoated, no chromatic aberration (color shift) waterproof, scratch resistant, and dustproof. Provides you with a perfect photography experience, protecting your lens from all around.
-【Ultra Slim Frame Avoid Vignetting】1.9mm-3.33mm ultra slim frame ensures no vignetting and dark corners on 16mm wide-angle focal length. CNC non-slip system frame, easy to install and remove.
Original Price £111.99
Discounted Price £94.99
-
Deal Discount £14.25
=
Final Payment £80.74
Total Save £31.25
New Arrival
K&F Concept Canon EW53 bayonet hood with a vacuum cleaning cloth *1, suitable for EF-M 15-45 mm f/3.5-6.3 IS STM; RF-S 18-45 mm f/4.5-6.3 IS STM and other lenses
K&F Concept Canon EW53 bayonet hood with a vacuum cleaning cloth *1, suitable for EF-M 15-45 mm f/3.5-6.3 IS STM; RF-S 18-45 mm f/4.5-6.3 IS STM and other lenses
£9.99
K&F Concept 2-Pack LP-E17 1040mAh Battery with USB C Fast Charging for Canon EOS R10, R8, R50, Rebel T8i, T7i, T6i, T6s, SL2, SL3, EOS M3, M5, M6, EOS 200D, 77D, 750D, 760D, 800D, 8000D
K&F Concept 2-Pack LP-E17 1040mAh Battery with USB C Fast Charging for Canon EOS R10, R8, R50, Rebel T8i, T7i, T6i, T6s, SL2, SL3, EOS M3, M5, M6, EOS 200D, 77D, 750D, 760D, 800D, 8000D
£32.99
K&F Concept LP-E12 Battery 3-Pack and Upgraded LCD EOS M50 Battery Charger for Canon M50, M50 Mark II, M, M2, M10, M100, M200, Rebel S1, PowerShot SX70 HS Cameras
K&F Concept LP-E12 Battery 3-Pack and Upgraded LCD EOS M50 Battery Charger for Canon M50, M50 Mark II, M, M2, M10, M100, M200, Rebel S1, PowerShot SX70 HS Cameras
£34.99
Charging Adapter Base for DJI Osmo Pocket 3, Desktop Type-C Charging Dock Fit Arca-Swiss Standard, with 1/4 Screw Hole/Folding Finger, Aluminum Alloy Bracket
Charging Adapter Base for DJI Osmo Pocket 3, Desktop Type-C Charging Dock Fit Arca-Swiss Standard, with 1/4 Screw Hole/Folding Finger, Aluminum Alloy Bracket
£20.99
4.5" Suction Cup Camera Mount with Double Ball Head Magic Arm, Mobile Phone Clamp, Gopro Adapter Accessories, 3/8" to 1/4" Adapter Screw, MS45
4.5" Suction Cup Camera Mount with Double Ball Head Magic Arm, Mobile Phone Clamp, Gopro Adapter Accessories, 3/8" to 1/4" Adapter Screw, MS45
£45.99
K&F CONCEPT Mini On-Camera Flash GN12, 5600K, 2000mAh Built-in Battery, Compatible with Canon, Fuji, Sony, Nikon, Panasonic, Olympus, Pentax & Other DSLR/Mirrorless Cameras with Standard Hot Shoe.
K&F CONCEPT Mini On-Camera Flash GN12, 5600K, 2000mAh Built-in Battery, Compatible with Canon, Fuji, Sony, Nikon, Panasonic, Olympus, Pentax & Other DSLR/Mirrorless Cameras with Standard Hot Shoe.
£39.99
Adjustable Iris Aperture Diaphragm M30 to M37 Iris Aperture Diaphragm Adapter Optical Diaphragm 1.5-26mm Lens Module Adapter Ring Optics PVS14
Adjustable Iris Aperture Diaphragm M30 to M37 Iris Aperture Diaphragm Adapter Optical Diaphragm 1.5-26mm Lens Module Adapter Ring Optics PVS14
£27.99
K&F Concept Canon ES68 II bayonet hood with a vacuum cleaning cloth *1 for Canon EF 50mm f/ 1.8STM lenses
K&F Concept Canon ES68 II bayonet hood with a vacuum cleaning cloth *1 for Canon EF 50mm f/ 1.8STM lenses
£9.99
K&F Concept 2-Pack 2600mAh LP-E6NH Battery and 18W Charger Compatible with Canon EOS R7, R5, R6, R, 5D Mark II/III/IV, 6D, 6D Mark II, 7D, 7D Mark II, 90D, 60D, 70D, 80D Cameras
K&F Concept 2-Pack 2600mAh LP-E6NH Battery and 18W Charger Compatible with Canon EOS R7, R5, R6, R, 5D Mark II/III/IV, 6D, 6D Mark II, 7D, 7D Mark II, 90D, 60D, 70D, 80D Cameras
£69.99
LP-E6/LP-E6NH Battery 2250mAh and 3-Slot Charger, 3-Pack Replacement Battery for Canon EOS R5, R6, EOS R, 5D Mark IV, 5D Mark III, 5DS, 5DS R, 5D Mark II, 6D, 6D Mark II, 7D, 7D Mark II
LP-E6/LP-E6NH Battery 2250mAh and 3-Slot Charger, 3-Pack Replacement Battery for Canon EOS R5, R6, EOS R, 5D Mark IV, 5D Mark III, 5DS, 5DS R, 5D Mark II, 6D, 6D Mark II, 7D, 7D Mark II
£56.99
Related Accessories
Clip-On ND Filter(1-9 stops) For Phone & 52mm Camera lens Adjustable Neutral Density Filter Compatible with iPhone Mobile Camera Filter
Clip-On ND Filter(1-9 stops) For Phone & 52mm Camera lens Adjustable Neutral Density Filter Compatible with iPhone Mobile Camera Filter
£26.99
K&F Concept Invisible Selfie Stick, Extension Long Pole（120cm/47.2in） for Insta360 Sports Camera GoPro DJI Action, 1/4
K&F Concept Invisible Selfie Stick, Extension Long Pole（120cm/47.2in） for Insta360 Sports Camera GoPro DJI Action, 1/4
£23.99
K&F Concept Alpha Camera Sling Bag 10L Photography Shoulder Bag, Compatible with Canon / Nikon / Sony Camears / DJI Mavic Drones, Sling Bag10L Urban Wander 01(Black )
K&F Concept Alpha Camera Sling Bag 10L Photography Shoulder Bag, Compatible with Canon / Nikon / Sony Camears / DJI Mavic Drones, Sling Bag10L Urban Wander 01(Black )
£43.99
ND2-32 & PL & Black Mist 1/4 Filter Kit Compatible with DJI Osmo Action 5 Pro/Osmo Action 4/Osmo Action 3, Snap-on Installation, no need to remove the original filter
ND2-32 & PL & Black Mist 1/4 Filter Kit Compatible with DJI Osmo Action 5 Pro/Osmo Action 4/Osmo Action 3, Snap-on Installation, no need to remove the original filter
£49.99
Camera Lens Filter Pouch Case, 4-Pocket Filter Carry Case, Belt Bag Pouch Water-Resistant shockproof and Dustproof Design for 37mm-95mm Filters
Camera Lens Filter Pouch Case, 4-Pocket Filter Carry Case, Belt Bag Pouch Water-Resistant shockproof and Dustproof Design for 37mm-95mm Filters
£21.99
Camera Lens Filter Pouch Case, 4-Pocket Filter Carry Case, Belt Bag Pouch Water-Resistant shockproof and Dustproof Design for 37mm-95mm Filters
Camera Lens Filter Pouch Case, 4-Pocket Filter Carry Case, Belt Bag Pouch Water-Resistant shockproof and Dustproof Design for 37mm-95mm Filters
£25.99 £21.99
K&F Concept V Mount Battery, 99Wh Mini V-Mount Battery, 6700mAh 14.8V Support 65W PD USB-C Fast Charger, with D-TAP, USB-A, USB-C, BP, OLED Screen, for Cameras and Camcorders
K&F Concept V Mount Battery, 99Wh Mini V-Mount Battery, 6700mAh 14.8V Support 65W PD USB-C Fast Charger, with D-TAP, USB-A, USB-C, BP, OLED Screen, for Cameras and Camcorders
£169.99 £139.99
K&F Concept 3-Way Geared Tripod Head CNC Process Aluminum Alloy, High-Precision Fluid Head Load Capacity up to 13.2lbs/6kg,for Photography Equipments
K&F Concept 3-Way Geared Tripod Head CNC Process Aluminum Alloy, High-Precision Fluid Head Load Capacity up to 13.2lbs/6kg,for Photography Equipments
£259.99 £189.99
K&F Concept replaceable Cleaning Pen Set, Full Frame Cleaning Stick*20
K&F Concept replaceable Cleaning Pen Set, Full Frame Cleaning Stick*20
£17.99
About Us

ABOUT KENTFAITH

-Enjoy Your Selected Digital Life

KentFaith as an end-consumer service provider, kentFaith is committed to improving consumer experience and providing consumers with the most suitable products. We have 150 patents and have won international product awards. We are popular in 200 countries and regions. We have been listening to the real needs of users and are committed to creating an ideal choice that meets your inner expectations and providing you with a convenient and practical exclusive shopping page.

20K + Products
56+ Countries and Regions
20Million+ Customers
150+ Patents
260+ Commercial Partners
1200+ Online and offine Retailers
20000+ Products
More Related Pages
Ef Eos R Mount Adapter
Ef Eos R Mount Adapter
£5.99 - £199.00
Ef To Eos R Adapter
Ef To Eos R Adapter
£19.99 - £199.00
Canon Eos R To Ef Adapter
Canon Eos R To Ef Adapter
£9.99 - £94.99
Canon Eos Ef To Rf Adapter
Canon Eos Ef To Rf Adapter
£9.99 - £94.99
Canon Ef To Fuji X Adapter Autofocus
Canon Ef To Fuji X Adapter Autofocus
£9.99 - £239.99
Canon Ef Eos R Mount Adapter
Canon Ef Eos R Mount Adapter
£5.99 - £52.99
Canon Ef To Eos R Adapter
Canon Ef To Eos R Adapter
£9.99 - £99.99
Canon Mount Adapter Ef Eos M
Canon Mount Adapter Ef Eos M
£5.99 - £52.99
Canon Mount Adapter Ef Eos R
Canon Mount Adapter Ef Eos R
£5.99 - £239.99
Ef Eos R Adapter
Ef Eos R Adapter
£18.99 - £94.99
Canon Ef To Eos M Adapter
Canon Ef To Eos M Adapter
£9.99 - £45.99
Ef Eos M Adapter
Ef Eos M Adapter
£18.99 - £94.99
Related searches
Canon Ef Eos R Adapter Ef Eos R Adapter Canon Eos R To Ef Adapter Canon Ef Eos R Mount Adapter Canon Ef To Eos R Adapter Canon Mount Adapter Ef Eos R Ef Eos R Mount Adapter Ef To Eos R Adapter Mount Adapter Ef Eos R Micro Four Thirds Lens
Popular searches
Camcorder With Wifi Streaming Tripod For Ipad Mini Canon Lens To Sony Body Adapter Black Mist Filter Fire Rated Smart Door Lock 4k Projector For Sports 3 Foot Antenna Tripod Yi Home Outdoor Camera Wireless Canon Film Camera With Ef Mount Micro Sd Card To Lightning Adapter
Related categories
Canon EF M Lens Mount Sony E mount adapter Canon RF Mount speedlight flash for canon lens hoods for canon lenses Ring Adapter Kit lens filter adapter ring micro four thirds lens adapter adapter rings for filters​ Black Mist 1/4
Popular products
canon ef-eos r mount adapter canon mirrorless adapter ef m mount adapter canon fd lens mount m42 mount adapter canon canon rf lens adapter canon eos m mount adapter canon minolta adapter canon f mount adapter canon r mount adapter