The Canon RF 85mm f/2 Macro IS STM is a versatile prime lens designed for Canon's full-frame mirrorless RF mount cameras. Here's a rundown of its key features:  
Optics and Image Quality:
85mm Focal Length: Ideal for flattering portraits with a natural perspective and pleasing subject isolation.  
Bright f/2 Aperture: Allows for beautiful background blur (bokeh) and excellent low-light performance.  
Macro Capability: Offers a maximum magnification of 0.5x (1:2), enabling close-up photography and revealing fine details. The minimum focusing distance is 0.35m (1.14 ft).  
Optical Image Stabilization (IS): Provides up to 5 stops of shake correction for sharper handheld images and smoother video. This can be further enhanced with in-body image stabilization (IBIS) on compatible EOS R cameras, achieving up to 8 stops of shake reduction.  
One UD Element: Helps to minimize chromatic aberrations and ensures high clarity and color accuracy.  
Super Spectra Coating: Reduces ghosting and flare for improved contrast and color fidelity in challenging lighting conditions.  
Nine-Blade Circular Aperture: Contributes to smooth and attractive bokeh.  
Autofocus and Handling:
STM (Stepping Motor): Delivers smooth and quiet autofocus, which is beneficial for both stills and video recording. It also offers full-time manual focus override.  
Configurable Control Ring: Allows direct adjustment of various camera settings like aperture, shutter speed, ISO, and exposure compensation directly from the lens.  
Lightweight and Compact: Weighs approximately 500g and has dimensions of 78 x 90.5mm, making it portable and easy to handle.  
Non-Weather Sealed: It's important to note that this lens does not feature weather sealing.  
Extending Barrel: The lens barrel extends when focusing closer to the subject.