• Sign in to Neowin Faster!

    Create an account on Neowin to contribute and support the site.

Sign in to follow this  

Digital camera equivalance and why you should care

Recommended Posts

Draconian Guppy    13,037

I'd like to post the whole article here, but because of formatting and photo examples, the article really deserves to be read at source:

 

The concept of 'equivalence*1' is still somewhat controversial and not always clearly understood. We thought it was about time we explained - and demonstrated - what equivalence means and what it doesn't.
 
What is equivalence?
 
Equivalence, at its most simple, is a way of comparing different formats (sensor sizes) on a common basis. This is already the way most lenses are talked about: it's quite common to say that a compact camera includes a '28-120mm lens' but the key and (often unspoken) word in that description is 'equivalent.' It's a simple way of describing the range of fields-of-view that the lens offers, cancelling out the effect of sensor size by using a common reference point.
 
A 100mm equivalent lens on a small-sensor camera will give the same framing and perspective as an actual 100mm lens does on a full-frame camera, regardless of sensor size, because they are equivalent.
 
 
 
 
This basically explains the difference between Full frame sensors, APS and mirrorless. Worth the read!

Share this post


Link to post
Share on other sites
Draconian Guppy    13,037

The snip that caught my attention:

 

As you can see, while the noise levels are much more similar, they're not actually the same (a simplistic measure of standard deviation from a common patch suggests the noise isn't solely related to sensor size, either).

There are a number of factors in play here, most likely dominated by differences in sensor performance, but with other complications such as differences in transmission between lenses. This is why we tend to state that, although equivalence can be used as a guide to low light performance, it can't be used to completely predict the differences.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.