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General Discussion => General Chat => Topic started by: ayoub on August 01, 2014, 01:22:27 PM

Title: [Looking for advice] 35mm prime lens on APS-C
Post by: ayoub on August 01, 2014, 01:22:27 PM
Hello everyone,

I am an owner of a T4i / 650 and I wanna buy a prime 35 mm lens (F 2.4 at least).
The problem is that due to the cropped sensors (APS-C) 35 mm, prime lenses are not common and often to get 35mm on APS-C you have to buy a zoom, I want avoid that.

So basically I have two choices:

Can someone recommend some prime lenses to have a 35mm aspect on an APS-C ?
Does the lenses for cropped sensor from other brands (the Nikon and Pentax mentioned before) keep the same focal length on a canon?

Thanks.

EDIT:
Can we use the EF-M lenses like this one (http://www.amazon.com/Canon-EF-M-22mm-Compact-System/dp/B008NF8BRI) on EF/EF-S mounts?
Title: Re: [Looking for advice] 35mm prime lens on APS-C
Post by: Oswald on August 01, 2014, 02:00:02 PM
Quote from: ayoub on August 01, 2014, 01:22:27 PM

EDIT:
Can we use the EF-M lenses like this one (http://www.amazon.com/Canon-EF-M-22mm-Compact-System/dp/B008NF8BRI) on EF/EF-S mounts?

No, you cant. This lens is designed for mirrorless cameras so flange distance is way shorter than mirror one. Eos M has same flange distance than sony mirrorless cameras.
Title: Re: [Looking for advice] 35mm prime lens on APS-C
Post by: nikfreak on August 01, 2014, 02:13:30 PM
Sigma 18-35mm 1.8. Top for APS-C. Know you don't want zoom but it's wort it..
Title: Re: [Looking for advice] 35mm prime lens on APS-C
Post by: jimmyD30 on August 01, 2014, 02:14:42 PM
You can use full-frame EF lenses on crop sensor cameras, but cannot use EF-S lenses on full-frame cameras.

I would suggest favoring getting EF mount lenses for a couple of reasons. One, they'll work on crop and full frame sensor cameras, so if you upgrade to say 5D/6D you won't have to buy new lenses. Two, crop sensor cameras use only the center of full-frame EF mount lenses, this is the sharpest part of the lens and you get very little (if any) light fall-off/vignetting, see here: http://www.the-digital-picture.com/Canon-Lenses/Canon-Lens-Vignetting.aspx

Caveats are the focal length changes using full frame lenses on crop sensor camera, must use multiplier (1.6 usually, some cameras 1.3) to determine new effective focal length. For example, a 35mm EF lens on 1.6x crop sensor camera would effectively be 56mm. Also, EF mount lenses are usually bigger/heavier (for primes, not really an issue, for zooms it can be) and more expensive.
Title: Re: [Looking for advice] 35mm prime lens on APS-C
Post by: ayoub on August 01, 2014, 03:00:58 PM
Quote from: jimmyD30 on August 01, 2014, 02:14:42 PM
Caveats are the focal length changes using full frame lenses on crop sensor camera, must use multiplier (1.6 usually, some cameras 1.3) to determine new effective focal length. For example, a 35mm EF lens on 1.6x crop sensor camera would effectively be 56mm. Also, EF mount lenses are usually bigger/heavier (for primes, not really an issue, for zooms it can be) and more expensive.

How about the optical distortion ? Because to get a "35mm" look on an APS-C I need a 24mm with EF mount. But 24mm applies a certain distortion to the image, would that disappear on a APS-C?   
Title: Re: [Looking for advice] 35mm prime lens on APS-C
Post by: jimmyD30 on August 01, 2014, 03:55:10 PM
See here: http://photo.stackexchange.com/questions/27923/distortion-quality-when-using-a-full-frame-lens-on-a-crop-sensor-camera

Basically, it'll be less in the center of the lens and it can be removed in post. And 24mm distortion isn't as bad as say 11mm or 17mm ;)
Title: Re: [Looking for advice] 35mm prime lens on APS-C
Post by: ayoub on August 01, 2014, 07:55:26 PM
Super thank you :)

I manged to find a pretty small Canon 24mm f2.0 which should give nice results.
Title: Re: [Looking for advice] 35mm prime lens on APS-C
Post by: brapodam on August 02, 2014, 02:22:31 AM
Quote from: ayoub on August 01, 2014, 03:00:58 PM
How about the optical distortion ? Because to get a "35mm" look on an APS-C I need a 24mm with EF mount. But 24mm applies a certain distortion to the image, would that disappear on a APS-C?
Any lens, regardless of the mount, when mounted on a crop factor body, will be affected by the crop factor. EF-S means it can only be mounted on crop frame bodies and not full frame. The focal length specification on the EF-S lens is not the 35mm equivalent.
Title: Re: [Looking for advice] 35mm prime lens on APS-C
Post by: Kharak on September 02, 2014, 10:12:57 AM
Take a look at the Rokinon 35 T1.5 cine lens.

It's a beast!
Title: Re: [Looking for advice] 35mm prime lens on APS-C
Post by: budafilms on September 02, 2014, 10:46:19 AM
Rokinon Sets Rocks!