Battle of the 50mm Primes


Day Eighty-Three:  Battle of the 50mm Lenses
Which 50mm lens is the best? The Canon EF 50mm f/1.8 II or the Canon EF 50mm f/2.5 Compact Macro?

I have as of a few months now, I have two 50mm prime lenses – the Canon EF 50mm f/2.5 Compact Macro and the Canon EF 50mm f/1.8 II.

I wanted to compare them to see if one is clearly better for another. After all, if I’m going to use a prime lens, why not use the best one? Before we get to the photo comparisons, let’s take a look at the other factors.

Weight

The f/1.8 not only looks to be about 60% of the size of the f/2.5 Macro, but it actually weights half as much.  B&H lists the f/1.8 at .29 lbs and the f/2.5 Macro at .61 lbs.  Neither one is exceptionally heavy, especially if you’ve ever held the EF 70-200mm f/2.8!  But if you require the lightest lens the f/1.8 is the way to go and over a long day may feel better.

winner:  f/1.8

Materials/Price

The f/1.8 is the cheapest EF lens Canon makes.  Although it has long been listed at $90, recent economic events have caused Canon to raise the price and it is now listed on B&H for $114.  Therefore it should be no surprise that it looks and feels cheap.  It’s wholly made of plastic and a lot of people complain that it feels cheap and that bothers them.  Frankly, as long as it doesn’t break easily I don’t care as long as the photos come out good.  (And they do!)  The f/2.5 is currently listed on B&H for $274.  It is definitely a more solid construction.  While parts of the body are plastic, the mount is metal and feels very snug when you mount it onto your EOS body.  Also it has a distance window for manual focus (as you can see below on the right).  Based on materials and price, basically you get what you pay for.

materials winner:  f/2.5

price winner: f/1.8

50mm f1.8 and 50mm f2.5 Compact Macro Focused Out
The extension length of the Canon EF 50mm f/1.8 II vs Canon EF 50mm f/2.5 Compact Macro

Maximum Focus Extension Length

As you can see above, the f/2.5, on the right, extends a lot further out when you’re focusing close than the f/1.8 does.  Is this a big deal?  It is to some people.  It means if you’re close to your subject you’ve gotta be a little careful.  It also tends to suck in more dust than a lens that doesn’t change length when focusing.  It’s really not that big a deal, but it does bother some.

winner: f/1.8

Focus ring

Whether you do it regularly or not, one day you will need to manually focus your camera.  The focus ring is what you turn in order to manually focus.  The f/2.5 has a decent-sized focus ring.  The f/1.8 has a vestigial ring that seems about to evolve right off the lens.  It’s more or less like the kit lens that came with the EOS 350D.  The f/2.5 wins without major contest.

winner: f/2.5

Closest Focal Distance

The f/1.8 can focus as close as 0.45 meters.  The f/2.5 macro can focus as close as 0.22 meters.  Makes sense – the f/2.5 is a MACRO lens.  So the f/2.5 easily wins.  Unless you don’t need the macro functionality.

Even More Flower Naughty Parts
A macro shot taken with the Canon EF 50mm f/2.5 Compact Macro

winner:  f/2.5, but trivial if you don’t ever intend on doing macro photography

Sound While Focusing

This is another one of those features that, like the extension of the lens when it focuses, bothers some, but not others.  It’s one of the selling points of why people buy USM lenses.  They are both orders of magnitude much louder than my USM lenses when they are auto focusing.  The f/2.5 is a bit louder than the f/1.8.  Does it matter?  Maybe, if you’re trying to photograph a baby without waking it up or an animal without startling it.  Or if you’re in a museum or church.  At the ball park no one will care.

winner:  f/1.8

Low Light Performance

In the same way that the f/2.5 automatically wins on the closest focal distance, the f/1.8 automatically wins on low light performance.  Opening the aperture all the way to  f/1.8 allows a lot more light into the lens and lets the photographer capture photos in lower light than they might otherwise be able to.  Using the f/1.8 you can take photos at night and not have to use your flash.  (If the conditions are right)

More Peeping
A low light photo taken with the Canon EF 50mm f/1.8 II

winner f/1.8

Now onto the photo comparisons.  I put my camera on a tripod and photographed the same scene at different f-stops to do a comparison to see where the lenses differ.  First off, opened up to their maximum apertures.

Maximum Aperture (f/1.8 and f/2.5)

50mm f1.8 Wide Open
Canon EF 50mm f/1.8 II Wide Open
50mm f2.5 Macro Wide Open
Canon EF 50mm f/2.5 Compact Macro Open Wide

First of all, the f/1.8 is (at 100% zoom) actually sharper wide open than the f/2.5.  On the other hand, the photo seems brighter in the f/2.5 photo.  So, wide open if you want sharper photos, the f/1.8 wins.  But colour-wise the f/2.5 wins.

winner:  tie

At f/2.8

50mm f1.8 @ f/2.8
Canon EF 50mm f/1.8 II @ f/2.8
50mm f2.5 Macro @ f/2.8
Canon EF 50mm f/2.5 Compact Macro @ f/2.8

Once again f/1.8 wins for sharpness.  This time the colour saturation is about the same.

winner: f/1.8

At f/8

50mm f1.8 @ f/8
Canon EF 50mm f/1.8 II @ f/8
50mm f2.5 Macro @ f/8
Canon EF 50mm f/2.5 Compact Macro @ f/8

I chose f/8 because it’s often recommended as a good f-stop for sharpness.  Now both lenses have the same sharpness.  f/1.8 has better colour saturation

winner:  tie

At f/11

50mm f1.8 @ f/11
Canon EF 50mm f/1.8 II @ f/11
50mm f2.5 Macro @ f/11
Canon EF 50mm f/2.5 Compact Macro @ f/11

f/11 is supposed to be the greatest you can stop your lens before diffraction starts to wreak havoc.  The f/2.5 is finally sharper.  The f/1.8  still has better colour saturation

winner:  f/2.5

Conclusions

First of all, this isn’t completely scientific.  I tried my absolute best to keep the camera in exactly the same place and to focus on the exact same place each time.  But I’m extremely surprised that the f/1.8 worked so darn well for the f-stops I tested.  I mean, in the real world I have been impressed with the f/1.8 in a way that I hadn’t been since I got the f/2.5, but I thought the macro would be better quality.

Well, based on features, the winner was the f/1.8 by 5 to 3.

Based on photos, it was a tie 3 to 3.

So basically you need to look at what types of photos you will be taken and buy your lens based on that.  They both appear to be very good, but the f/1.8 eeked ahead and is recommended for your first prime lens, especially if money is a concern.  But if you want to explore macro, you can’t beat the f/2.5.  Hope that helps, I know I was very surprised with the results.


4 responses to “Battle of the 50mm Primes”

  1. […] A new writeup I wrote comparing the EF 50mm f/1.8 and the EF 50mm f/2.5 Compact Macro. See it here. __________________ Eric There are no new ideas, just new interpretations on the old ones. My […]

  2. Its an old topic but:

    I have also both and in my tests the “compact macro” wins.

    If you setup a low light scene then you will see that the 1.8 has softer corners while the “compact 2.5” is slightly sharper. The 2.5 shows wide open lesser contrast which some people review as “not as sharp” but it is sharp.

    At f4 and f8 the 2.5 wins in my case.

    It is a slight win but only the EF-S 60mm can smoke both regarding sharpness.

    I payed 115 Euro including shipping for my 2.5 compact macro. It is better build than the 1.8 and so the 1.8 will be sold.

    At daylight both are sharp…..but the 2.5 can Macro very close.

    cheers

    Rick

    • You bring up some good points. However, I would contend if you’re going with such a large aperture that the corners don’t matter as much. I agree that if you want a macro image, you must get the macro. Check out the one I took today: http://www.flickr.com/photos/ericsbinaryworld/8668627066/in/photostream

      You couldn’t get that with the f1.8. But if you really want a prime for the ability to open wide, then I think the f1.8 is a better deal.

      In the end they’re both just so close it’s hard to say definitively.