A unique and indispensable addition to Canon’s series of EF lenses, the new EF 40mm f/2.8 STM offers an ultra-slim and lightweight design. Incredibly compact in size, the 40mm f/2.8 lens delivers high image quality from the center to the periphery, thanks to its advanced lens configuration including an aspherical element, a bright 2.8 aperture, and optimized coatings that minimize ghosting and flare, while providing exceptional color balance.
Here are the main highlights:

• STM - Continuous Autofocus for Shooting Video
  
• Lightweight 4.6 oz Lens
  
• Unobtrusive--Less Than 1" Long
  
• Aspherical Element--High Image Quality
  
• Optimized Coatings Reduce Ghost & Flare

Having a small lens is nice if you have a slimmer body like the micro four thirds camera, but if you have a dslr then 1inche or 3-4 inches, it really doesn't matter. May be Canon is making a move towards 4/3rds by launching this, I don't know. Why not a cheap 17mm or 14mm f4 rather than 40mm. And I will rather buy the 1.8 for half the price.

To Canon: Instead make it two/three inches and make it faster. And we have a two 30s and three 50s prime. Give us 14-24 or cheaper ultra wides.

I was hoping it would compete better (speed wise) with the voightlander 40mm offering, but at 2.8 . It's probably gonna be sharp as a tack and it's super light but not gonna do it for a 2.8

If it's sharp as a tack it could end up being a fun lens for street shooting. A small unobtrusive autofocus lens. I don't know, but I'm looking forward to seeing what this thing can do!

Kaustubh wrote:
Having a small lens is nice if you have a slimmer body like the micro four thirds camera, but if you have a dslr then 1inche or 3-4 inches, it really doesn't matter..

Honestly, I'm already thinking how small a package this will be on a Rebel body (my wife better lock hers up). If you are a Canon user, this is as small as it gets, and I've resisted the urge to buy into yet another platform just to have another, smaller camera.

This is perfect for street phtography. I rented the Voighlander a year ago and it was fun. i'm sure this will be fun as well. I pre-order mine today.

This looks to be aimed at shooting video with the 4Ti with the STM unstead of USM, but would make a nice little lens.

I meant to ask this question here. Sorry for the other post but I would like to jnow if lenses get tried out before they ship, similiar to a premodel Camera. Does everyone just preorder and if its no good return it it or sell it?

I was thinking the same this as above. Is USM being replaced by this STM?