How to Identify Your Lens' Sweet Spot - Digital Photography School

How to Identify Your Lens’ Sweet Spot

Canon-Ef-24-105Mm-Lens-1Have you noticed that the sharpness of shots coming out of your camera can vary quite a bit from image to image?

Earlier today I was looking at some of the shots I took over the weekend and noticed that even though on one shoot I didn’t change lenses and that the lighting conditions and scene didn’t change much that the sharpness of my images varied quite a bit from shot to shot.

One shot would be crystal clear and the next would have a murkiness to it.

What was going on?

There are many many factors that can change the sharpness of an image but as I analyzed my shots I realized that the one that seemed to be coming into play in this situation was the aperture I was using in shots.

In the middle of my lens’ aperture range the shots were sharp – but at both ends (particularly when it was wide open – where the numbers are smallest) the shots got a little blurrier).

Most lenses have have a ‘sweet spot’ or a range in their aperture where they work at their best and produce the sharpest images.

Tangent- when I had tennis training as a child my coach spent a lot of time talking about the ‘sweet spot’ on my tennis racquet. It was a spot that would give me ultimate power when playing a stroke and my coach spent a lot of time helping me to learn to hit balls there. In a similar way – if you learn to know where a lens’ sweet spot is you can use it more effectively.

In many lenses this sweet spot is one or two stops from the maximum aperture. So on my f/4 lenses I tend to get sharper results in the f/5.6 to f/8 range (or even smaller).

How to Identify Your Lens’ Sweet Spot

Of course the sweet spot varies from lens to lens and it is worth doing some analysis of your images – here’s how I do it when I get a new lens.


  1. Take your lens out for a photo shoot and make a concerted effort to shoot at it’s full range of apertures – ie switch your camera to aperture priority mode and then take multiple shots of the same scene at different apertures.
  2. When you upload your shots onto your computer and scan through your shots pay attention to your EXIF data – particularly the aperture settings.
  3. As you scan through your shots (look at them at 100% resolution) you should notice some that are sharper than others. Check what aperture these shots are taken at and you’ll begin to get a feel for where your lens is at its sharpest.

So What?

Does this mean you should avoid shooting outside your lens’ sweet spot?

No – that’s not the point of this exercise. There will be times where I’ll need to shoot with my lens wide open (for example in low light or where I want to have a small depth of field) – however it is worth knowing what the consequences of doing so will be – it is about knowing the strengths and weaknesses of your gear and shooting in a way that brings out the best in it.

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Darren Rowse is the editor and founder of Digital Photography School and SnapnDeals. He lives in Melbourne Australia and is also the editor of the ProBlogger Blog Tips. Follow him on Instagram, on Twitter at @digitalPS or on Google+.

  • Fatih

    Hi,

    Alternatively, you may check your lens’ blur index at
    http://www.slrgear.com/reviews/index.php

  • http://3files.blogspot.com/ Eugene Sakhnenko

    There are other factors that could be influencing your results. Usually the “sweet spot” is a certain focal lenght not a certain aperture. That’s whay prime lenses are sharper than zooms because they only have one focal length. The reason it might seem that the middle aperture is the sharpest is because at a large aperture there is very shallow depth of field and thus even focusing slightly off your subject results in out of focus shots. If your shooting at a small aperture then the shutter speed required to expose the shot is usually very long, thus the slightest movement will result in a blurry shot. Having said that, you can achive the sharpest possible image by using the smallest (biggest number) aperture, and a good tripod as long as your subject isn’t moving of course.

  • http://www.flickr.com/photos/obiwan_tjk/ obiwan

    Thanks, just the advice i was looking for!

  • http://www.homeschoolblogger.com/juliestew Julie

    Just wanted to say thanks for the help in understand sweet spots. I spent a lot of time this summer learning more but I find there is always more to learn. Now that school has begun again (we’re a homeschooling family) I have little time to do anything but point and shoot. Gone is the time to just play.
    I really enjoy your website/blog.
    julie

  • Yvonne

    I photograph dancer ..moving targets in low light.finding the sweet spot is interesting because some of my photos are sharper than others …anyone want to give me some more tips ….also How to take group photo’s and getting everyone in sharp focus, what Aperture and shutter speed is best for geting max depth of field ?

    Yvonne

  • Eric

    yvonne-

    It’s likely that some of your shots are sharp because of the dancer pausing. With movement, you need the fastest shutter speed possible. With group shots, a wider aperture (smaller number) but small enough to get everyone in focus.

    What kind of gear are you using?

  • claire

    hey eric,

    just following up on yvonne’s thread. if i’m using a sigma 30mm f 1.4 whats the best aperture i shld be using to get a group shot that has everyone in focus?

    cheers

  • http://moorephotography.net Eric

    That depends on the size of the group. f8 might be a good starting point, but I wouldn’t let your shutter go below 1/100 or 1/80 if you’re hand holding, maybe 1/60 on a tripod. Also, don’t crank your ISO up to high.

    Does this help?

  • Galo

    HI DARRN,

    kIND REGARDS FROM ECUADOR,

    U GET THE HELL OF A SITE HERE…FINALLY I COULD FIND SUCH A NICE AND PRACTIAL, CONGRATS!!………..QUESTION: WITH LOW LITES AND WITH A WIDE APERTURE, YOU CANT AVOID THE NOISE IN THE PICTURE…IS THERE A WAY TO GET RID OF IT? I HAVE A FUJI FINEPIX S1000, NICE CAMERA FOR BEGINERS I GESS BUT NOW…IS OUT OF PRODUCTION…ANY COMMENTS FROM YOU ABOUTTHIS CAMERA??

    THANKS….DON’T EVER STOP DARREN.
    GALO

  • J

    or you could just shoot Nikkor and not worry about it :-)

  • Maury Gollob

    RELATED TO THE SUBJECT OF SWEET SPOTS AND CLARITY OF FOCUS ARE THE FACTORS OF CAMERA SHAKE,, RELYING ON AUTOFOCUS AND THE USE OF A TRIPOD. THE THIRD FACTOR CAN HELP REDUCE THE FIRST ONE, AS CAN THE USE OF A RELEASE CABLE. THE SECOND FACTOR IS THE ONE I FIND MOST FRUSTRATING! IN THE ATTEMPT TO CAPTURE THE MOMENT, SOME PHOTOGRAPHERS WILL USE THE AUTO FOCUS MODE AND DOING SO PUTS ONE AT RISK FOR THE CAMERA SENSOR SEEKING THE OBJECT OF GREATEST CONTRAST AND NOT NECESSARILY THE CENTER OF INTEREST THE PHOTOGRAPHER HAD IN MIND.

    THOSE OF US WHO ARE GROWING OLD FIND HOLDING THE CAMERA STEADY A MU;CH MORE DIFFICULT TASK THAN WHEN WE WERE MUCH YOUNGER. I FIND MYSELF FACING NEW CHALLENGES WITH REGARD TO REDUCING CAMERA SHAKE. SO FAR, CAMERA BRACKETS AND A TRUSTY TRIPOD SEEM TO WORK BEST. AND FOR YOUR INFORMATION, GROWING OLD IS NOT FOR SISSIES, BUT IT SURE BEATS THE ALTERNATIVE!

    AS ALWAYS, THINGS IMPROVE WITH PRACTICE.

    WITH BEST REGARDS, MAURY

    .

  • http://www.photoschooldropout.com M Kenneth Petruzzi

    Most mfgs. optimize the lens design (especially in their more economical lenses) so that the middle range of f/stops (f/5.6-f8) are the sharpest. In the most expensive, or special purpose lenses, extra care and cost are put into expanding the sweet spot. That’s one reason that in Photography School, we used to say “Be there and shoot at f/8? as advice to newbies. LOL.

    That said, sometimes you WANT some nice edge softness, like in a fast 75, 80, or 105mm, wide open, on a portrait. It’s always up to us, of course, to learn our gear, and maximize our use of it to make affecting images.

    Good convo!

    -PhotoSchoolDropout.com

    Read more: http://www.digital-photography-school.com/find-your-lens-sweet-spot#ixzz1G7llosKP

  • Alex Lexo

    Have a look at this interactive tool which gives the results from lens tests. Many lenses are tested on more than one camera – often a full frame as well as a prosumer body. It’s REALLY good to find those sweet spots for either noise, sharpness or distortion. It gives you the option of changing the aperture as well as the focal length as, obviously, these are the two factors which one can control. It’s also great to see the difference the camera body makes and with those purchasing decisions.

    http://www.dpreview.com/lensreviews/widget/Fullscreen.ashx?reviews=30&fullscreen=true&av=1.667&fl=50&vis=VisualiserSharpnessMTF&stack=horizontal&&config=LensReviewConfiguration.xml%3F2

  • ccting

    Do we have the list of sweet points vs lenses available in the web?

Some older comments

  • ccting

    September 8, 2012 10:27 pm

    Do we have the list of sweet points vs lenses available in the web?

  • Alex Lexo

    September 21, 2011 08:53 pm

    Have a look at this interactive tool which gives the results from lens tests. Many lenses are tested on more than one camera - often a full frame as well as a prosumer body. It's REALLY good to find those sweet spots for either noise, sharpness or distortion. It gives you the option of changing the aperture as well as the focal length as, obviously, these are the two factors which one can control. It's also great to see the difference the camera body makes and with those purchasing decisions.

    http://www.dpreview.com/lensreviews/widget/Fullscreen.ashx?reviews=30&fullscreen=true&av=1.667&fl=50&vis=VisualiserSharpnessMTF&stack=horizontal&&config=LensReviewConfiguration.xml%3F2

  • M Kenneth Petruzzi

    March 10, 2011 04:26 am

    Most mfgs. optimize the lens design (especially in their more economical lenses) so that the middle range of f/stops (f/5.6-f8) are the sharpest. In the most expensive, or special purpose lenses, extra care and cost are put into expanding the sweet spot. That’s one reason that in Photography School, we used to say “Be there and shoot at f/8? as advice to newbies. LOL.

    That said, sometimes you WANT some nice edge softness, like in a fast 75, 80, or 105mm, wide open, on a portrait. It’s always up to us, of course, to learn our gear, and maximize our use of it to make affecting images.

    Good convo!

    -PhotoSchoolDropout.com

    Read more: http://www.digital-photography-school.com/find-your-lens-sweet-spot#ixzz1G7llosKP

  • Maury Gollob

    December 7, 2010 04:06 pm

    RELATED TO THE SUBJECT OF SWEET SPOTS AND CLARITY OF FOCUS ARE THE FACTORS OF CAMERA SHAKE,, RELYING ON AUTOFOCUS AND THE USE OF A TRIPOD. THE THIRD FACTOR CAN HELP REDUCE THE FIRST ONE, AS CAN THE USE OF A RELEASE CABLE. THE SECOND FACTOR IS THE ONE I FIND MOST FRUSTRATING! IN THE ATTEMPT TO CAPTURE THE MOMENT, SOME PHOTOGRAPHERS WILL USE THE AUTO FOCUS MODE AND DOING SO PUTS ONE AT RISK FOR THE CAMERA SENSOR SEEKING THE OBJECT OF GREATEST CONTRAST AND NOT NECESSARILY THE CENTER OF INTEREST THE PHOTOGRAPHER HAD IN MIND.

    THOSE OF US WHO ARE GROWING OLD FIND HOLDING THE CAMERA STEADY A MU;CH MORE DIFFICULT TASK THAN WHEN WE WERE MUCH YOUNGER. I FIND MYSELF FACING NEW CHALLENGES WITH REGARD TO REDUCING CAMERA SHAKE. SO FAR, CAMERA BRACKETS AND A TRUSTY TRIPOD SEEM TO WORK BEST. AND FOR YOUR INFORMATION, GROWING OLD IS NOT FOR SISSIES, BUT IT SURE BEATS THE ALTERNATIVE!

    AS ALWAYS, THINGS IMPROVE WITH PRACTICE.

    WITH BEST REGARDS, MAURY

    .

  • J

    June 4, 2010 05:14 am

    or you could just shoot Nikkor and not worry about it :-)

  • Galo

    May 9, 2010 05:14 pm

    HI DARRN,

    kIND REGARDS FROM ECUADOR,

    U GET THE HELL OF A SITE HERE...FINALLY I COULD FIND SUCH A NICE AND PRACTIAL, CONGRATS!!...........QUESTION: WITH LOW LITES AND WITH A WIDE APERTURE, YOU CANT AVOID THE NOISE IN THE PICTURE...IS THERE A WAY TO GET RID OF IT? I HAVE A FUJI FINEPIX S1000, NICE CAMERA FOR BEGINERS I GESS BUT NOW...IS OUT OF PRODUCTION...ANY COMMENTS FROM YOU ABOUTTHIS CAMERA??

    THANKS....DON'T EVER STOP DARREN.
    GALO

  • Eric

    January 30, 2010 06:27 am

    That depends on the size of the group. f8 might be a good starting point, but I wouldn't let your shutter go below 1/100 or 1/80 if you're hand holding, maybe 1/60 on a tripod. Also, don't crank your ISO up to high.

    Does this help?

  • claire

    January 29, 2010 11:24 am

    hey eric,

    just following up on yvonne's thread. if i'm using a sigma 30mm f 1.4 whats the best aperture i shld be using to get a group shot that has everyone in focus?

    cheers

  • Eric

    July 17, 2009 07:40 am

    yvonne-

    It's likely that some of your shots are sharp because of the dancer pausing. With movement, you need the fastest shutter speed possible. With group shots, a wider aperture (smaller number) but small enough to get everyone in focus.

    What kind of gear are you using?

  • Yvonne

    April 6, 2009 03:11 am

    I photograph dancer ..moving targets in low light.finding the sweet spot is interesting because some of my photos are sharper than others ...anyone want to give me some more tips ....also How to take group photo's and getting everyone in sharp focus, what Aperture and shutter speed is best for geting max depth of field ?

    Yvonne

  • Julie

    September 7, 2008 02:58 am

    Just wanted to say thanks for the help in understand sweet spots. I spent a lot of time this summer learning more but I find there is always more to learn. Now that school has begun again (we're a homeschooling family) I have little time to do anything but point and shoot. Gone is the time to just play.
    I really enjoy your website/blog.
    julie

  • obiwan

    September 4, 2008 12:49 pm

    Thanks, just the advice i was looking for!

  • Eugene Sakhnenko

    November 8, 2006 10:35 am

    There are other factors that could be influencing your results. Usually the "sweet spot" is a certain focal lenght not a certain aperture. That's whay prime lenses are sharper than zooms because they only have one focal length. The reason it might seem that the middle aperture is the sharpest is because at a large aperture there is very shallow depth of field and thus even focusing slightly off your subject results in out of focus shots. If your shooting at a small aperture then the shutter speed required to expose the shot is usually very long, thus the slightest movement will result in a blurry shot. Having said that, you can achive the sharpest possible image by using the smallest (biggest number) aperture, and a good tripod as long as your subject isn't moving of course.

  • Fatih

    November 7, 2006 12:51 am

    Hi,

    Alternatively, you may check your lens' blur index at
    http://www.slrgear.com/reviews/index.php

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