{"id":67297,"date":"2025-02-28T12:45:48","date_gmt":"2025-02-28T11:45:48","guid":{"rendered":"https:\/\/phillipreeve.net\/blog\/?p=67297"},"modified":"2025-09-29T19:25:57","modified_gmt":"2025-09-29T18:25:57","slug":"review-viltrox-af-25mm-f-1-7-air-aps-c","status":"publish","type":"post","link":"https:\/\/phillipreeve.net\/blog\/review-viltrox-af-25mm-f-1-7-air-aps-c\/","title":{"rendered":"REVIEW: Viltrox AF 25mm f\/1.7 Air (APS-C)"},"content":{"rendered":"

Introduction<\/span><\/h2>\n

\"Nikon<\/span><\/p>\n

About two months ago, Viltrox released a 35mm f\/1.7 for APS-C cameras. It seems they\u2019ve been busy, as they\u2019ve now introduced the 25mm f\/1.7 in their Air series. Officially named the Viltrox AF 25mm f\/1.7 Air STM ASPH IF<\/strong>, it certainly comes with a lot of acronyms to keep track of!<\/p>\n

This is an unusual focal length, equivalent to 37.5mm<\/strong> on a full-frame camera\u2014sitting between the classic 35mm and 40mm, both popular choices for everyday and street photography. Let\u2019s take a closer look!<\/p>\n

\"camera-icon2\"I tested the lens on a Nikon Zfc<\/a>
\n\"\"You can see this review as\u00a0a\u00a0YouTube\u00a0video\u00a0here<\/a>!
\n\"\"Sample images in high resolution here<\/span><\/a>.<\/p>\n

Sample Images<\/span><\/h2>\n
\"\"
Nikon Zfc | Viltrox AF 25mm F\/1.7 Air (STM ASPH ED IF) | f\/5<\/figcaption><\/figure>\n
\"\"
Nikon Zfc | Viltrox AF 25mm F\/1.7 Air (STM ASPH ED IF) | f\/7.1<\/figcaption><\/figure>\n
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Nikon Zfc | Viltrox AF 25mm F\/1.7 Air (STM ASPH ED IF) | f\/4<\/figcaption><\/figure>\n
\"\"
Nikon Zfc | Viltrox AF 25mm F\/1.7 Air (STM ASPH ED IF) | f\/1.7<\/figcaption><\/figure>\n
\"\"
Nikon Zfc | Viltrox AF 25mm F\/1.7 Air (STM ASPH ED IF) | f\/5<\/figcaption><\/figure>\n
\"\"
Nikon Zfc | Viltrox AF 25mm F\/1.7 Air (STM ASPH ED IF) | f\/8<\/figcaption><\/figure>\n

<\/p>\n

\"\"
Nikon Zfc | Viltrox AF 25mm F\/1.7 Air (STM ASPH ED IF) | f\/1.7<\/figcaption><\/figure>\n
\"\"
Nikon Zfc | Viltrox AF 25mm F\/1.7 Air (STM ASPH ED IF) | f\/4<\/figcaption><\/figure>\n
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Nikon Zfc | Viltrox AF 25mm F\/1.7 Air (STM ASPH ED IF) | f\/16<\/figcaption><\/figure>\n
\"\"
Nikon Zfc | Viltrox AF 25mm F\/1.7 Air (STM ASPH ED IF) | f\/1.7<\/figcaption><\/figure>\n
\"\"
Nikon Zfc | Viltrox AF 25mm F\/1.7 Air (STM ASPH ED IF) | f\/8<\/figcaption><\/figure>\n
\"\"
Nikon Zfc | Viltrox AF 25mm F\/1.7 Air (STM ASPH ED IF) | f\/4<\/figcaption><\/figure>\n

Most of the sample images in this review and many more can be found in higher resolution here.<\/span><\/p>\n

<\/span><\/p>\n

Specifications<\/span><\/h2>\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Focal Length<\/td>\n25mm<\/td>\n<\/tr>\n
Angle of View<\/td>\n60\u00b0<\/td>\n<\/tr>\n
# of Aperture Blades<\/td>\n9<\/td>\n<\/tr>\n
Max Aperture<\/td>\nf\/1.7<\/td>\n<\/tr>\n
Min Aperture<\/td>\nf\/16<\/td>\n<\/tr>\n
Min Focus Distance<\/td>\n0.3 m<\/td>\n<\/tr>\n
Filter Size<\/td>\n52mm<\/td>\n<\/tr>\n
Lens Mount<\/td>\nXF \/ E \/ Z<\/td>\n<\/tr>\n
Weight<\/td>\n170 g (X\/E)
\n180 g (Z)<\/td>\n<\/tr>\n
Size (D x L)<\/td>\n64 x 54.4 mm (E)
\n64 x 56.4 mm (Z)
\n64 x 54.7 mm (XF)<\/td>\n<\/tr>\n
Elements\/Group<\/td>\n12 \/10<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\"\"
Viltrox AF 25mm F\/1.7 STM ASPH ED IF | Lens construction<\/figcaption><\/figure>\n
\"\"
Viltrox AF 25mm F\/1.7 STM ASPH ED IF on a Nikon Zfc<\/figcaption><\/figure>\n\n\n\n
Buy new:<\/strong> Viltrox Store<\/a>, Amazon<\/a>, , B&H for $176 (Affiliate links)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Disclosure<\/span><\/p>\n

Viltrox kindly provided this lens for test and review purposes.<\/p>\n

Handling<\/span><\/h2>\n

The Viltrox 25mm f\/1.7<\/strong> features a sleek, minimalist design<\/strong>, with no controls other than its relatively large focus ring. The lens is primarily made of durable hard plastic<\/strong>, while the mounting plate is metal<\/strong>. Weighing just 170 g<\/strong>, it is compact and lightweight<\/strong>, though slightly larger than the recently released Viltrox 35mm f\/1.7<\/strong>, which is also part of the Air series.<\/p>\n

\"\"
Viltrox AF 35mm f\/1.7 vs 25mm F\/1.7 STM ASPH ED IF<\/figcaption><\/figure>\n

The focusing system is focus-by-wire, and the focus ring turns very smoothly. The lens features an internal focusing mechanism, meaning it does not change length while focusing, and the front element does not rotate\u2014a benefit for filter users.<\/p>\n

The autofocus system uses a stepper motor for precise and accurate focusing. Autofocus is fast and reliable.<\/p>\n

The focus ring can be configured to control manual focus, aperture settings, or exposure compensation, or it can be completely disabled.<\/p>\n

The metallic mounting plate feature a USB-C port for future firmware updates.<\/p>\n

\"\"
Viltrox AF 25mm F\/1.7 STM ASPH ED IF<\/figcaption><\/figure>\n

The lens comes with front and rear caps, a sturdy hard plastic petal-shaped lens hood, and a cloth pouch.<\/p>\n

\"\"
Viltrox AF 25mm F\/1.7 STM ASPH ED IF | Front & read caps, lens hood, and cloth pouch<\/figcaption><\/figure>\n

Optical Features<\/span><\/h2>\n
\"\"
Viltrox AF 25mm F\/1.7 STM ASPH ED IF | MTF graph<\/figcaption><\/figure>\n

Sharpness (Infinity)<\/span><\/h3>\n

For the infinity sharpness test, we look at three areas of the image, centre, mid-frame, and corner, see highlighted areas in the image below!<\/span><\/p>\n

\"\"
Infinily Sharpness Points of Inspection<\/figcaption><\/figure>\n

\"Infinity-sharpness-Viltrox-25-1-7-Air\"<\/p>\n

The lens delivers excellent sharpness in the centre and midframe, with very good sharpness in the corners right from f\/1.7. Stopping down further improves sharpness across the frame, reaching peak performance around f\/4-f\/5.6. At f\/11, sharpness softens slightly, and diffraction becomes more noticeable at f\/16, though overall performance remains very good<\/p>\n

Sharpness (Portrait)<\/span><\/h3>\n

Let\u2019s look at the points of interest for portraits at the portrait distance: the very centre, the centre\u2019s inner periphery\u00a0 (1\/3 rule intersection), and the centre\u2019s outer periphery (1\/4th intersection).<\/span><\/p>\n

\"\"
Portrait Sharpness Points of Interest<\/figcaption><\/figure>\n