Photographers often want to use the slowest possible shutter speed while still achieving the sharpest possible shot when handheld. Â The answer to “how slow of a shutter speed you can use” when shooting handheld is important because not getting it right results in thousands of ruined photos. Â Every photographer takes those thousands of blurry shots until he or she learns the limits of shutter speed. Â I'm hoping to save you a bit on that learning curve with this article.
But if you're just looking for the quick answer to this question, check out the graphic below.  I hope it clarifies things, because otherwise I just wasted the last 3 hours trying to make it for you 🙂
In the chart above, I consider “poor” sharpness to be where the sharpness is not good enough to publish most of the shots, even if a lucky sharp one appears now and again. Â “Fair” sharpness means that at least 40% of the shots are turn out reasonably sharp. Â “Good” sharpness means that at least 75% of the shots turn out reasonably sharp. Â “Great” means that almost all of the shots turn out sharp, and the general sharpness is higher than that of any of the other categories.
By the way, it took me a couple hours of standing out in the freezing cold at 6:30AM in my backyard testing for this chart using camera bodies and lenses from two manufacturers to get a good general rule for each shutter speed and focal length. Â Obviously, your mileage will vary slightly depending on how good your technique is. Â I've been shooting professionally for a few years, but my hands were trembling from the cold, so you can judge for yourself if you may want to put your own general rules a little faster or slower than the chart.
The Focal Length vs. Shutter Speed Rule
The simplest answer to how slow of a shutter speed you can use and still get a sharp picture is to use the 1/focal length rule. The shutter speed/focal length rule says you simply take the focal length you're shooting at (let's say 50mm, for an example), and make the denominator in your shutter speed.  Simple!  So if you're shooting with a 50mm lens, the rule says that you shouldn't pick a shutter speed slower than 1/50 if you want a sharp picture.  So you could shoot at 1/80 or 1/100 and be just fine, but don't go to 1/40 or 1/20.
Another example: if you're shooting at 200mm, the rule says you should not shoot slower than 1/200. Â So 1/400 or 1/640 or faster is fine, but don't choose 1/180 or anything else under 1/200.
There are several issues with taking the 1/focal length rule as the final word on the subject: (1) If you are using a crop sensor camera, do you add the crop factor to the equation? Â (2) What about image stabilization, wouldn't that allow you to achieve a sharper shot at a slower shutter speed? (3) Does the rule break down at very long and very short shutter speeds? Â The answer to all three of these questions, is “yes!”
Why Focal Length and Shutter Speed are Related
But first, at a basic level, we need to discuss WHY the shutter speed and focal length are related. Â I like to think of the example of holding a laser light. Â If you get a red laser pointer and point it against the desk in front of you, you can hold the point pretty steady. Â You won't see the point dancing around much. Â If you point the laser at a house across the street, no matter how hard you try to hold the laser steady, it will dance around wildly. Â You haven't changed the way you're holding the laser, and technically you were just as shaky in both situations, but the shake is exacerbated greatly by distance, which multiplies the effect.
When holding a camera, the same thing happens. Â A minor shake when shooting wide can't be seen much because the viewer isn't zoomed in on the tiniest details. Â HOWEVER, when you're shooting a very long lens, the viewer sees the details and any shake in the camera muffles those details, creating a soft image.
Aside from choosing the correct focal length, it's extremely important that you learn the proper way to hold a DSLR. Â I'm amazed sometimes when I see how photographers hold the camera. Â If you don't prop up the lens with the palm of your left hand, you're unlikely to get a sharp shot with a longer lens.
How Crop Factor Affects the Shutter Speed Rule
Generally, when photographers talk about different focal lengths, they mean the focal length on a full frame camera. Â If you use an APS-C (so called “crop sensor”) DSLR, then you need to multiply the focal length by 1.5 (Nikon, Fuji, or Sony crop sensor) or 1.6 (Canon crop sensor) in order to get the equivalent focal length. Â So a 50mm lens, when put on a full frame camera is 50mm. Â But when it's put on an APS-C sensor, has the equivalent focal length of about 75mm.
That may leave you wondering why, in the chart above, the numbers for crop sensor are all lower than those in the full frame columns.  The reason is the field of view, which is the number we need for the proper calculation above.  In that scenario, we are not saying that the same lens is put on both cameras, but it is trying to show what focal lengths produce the same field of view, and what shutter speeds can be used at those focal lengths to produce a sharp image.
If you forget about the chart and want to just do the calculation on your own for the 1/ focal length rule, then you would first figure out the equivalent focal length, and then use the rule normally. Â So if your lens is zoomed to 40mm, you would need a shutter speed not of 1/40 (which is the rule for a full frame shutter speed calculation). Â You would multiply 40mm x 1.5 (the crop factor for your crop sensor) and get an answer of 60. Â Now apply the 1/focal length rule and you know you need a shutter speed of at least 1/60.
If you don't want to do that calculation every time, just use the chart above. Â I've done the hard work for you. Â But also, don't turn sharpness into a math problem. Â The 1/focal length rule is a GENERAL rule and is not at all a perfect science. Â It just gives you a starting place.
You may be tempted to say that only the picture on the left is “sharp enough for your standard.” But remember that these are zoomed in all the way. If you're viewing the first three photos at a normal size online, you couldn't tell the difference at all between them.
Sharpness Means Different Things In Different Situations (to different people!)
The chart above, and generally how photographers talk about sharpness is as if there are only two options: sharp and blurry. Â That's not really the case. Â Sharpness is a range. Â The 1/focal length rule gives you an approximation for the slowest shutter speed you can go to and still get a reasonably sharp image about 80% of the time. Â You'll still take some blurry shots if you're at the minimum. Â But the more interesting question is–what constitutes a “sharp” photo?
If I were taking a photo that I knew was going to be printed huge, or which I was going to later crop, I would have a very different standard for sharpness than some other photos, because I'll be zooming in to see the little details.
Further, as cameras increase in resolution, the standard for sharpness only increases. Â Only a few years ago when I started to do photography professionally, I was shooting on a 10 megapixel DSLR. Â Now, DSLRs commonly shoot 24 to 36 megapixel images–and higher! Â Since we're able to capture more fine detail, the tiniest softness in detail will be visible on the image, so the standard for sharper and sharper images has gone up dramatically.
If you're shooting mission-critical images where you know sharpness needs to be perfect, do NOT shoot right at the 1/focal length rule. Â You'll want to click a little further on the shutter speed wheel.
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Hi Jim
I watched your video and In my opinion a 50mm stays a 50mm. It is the field of view that is affected. It is an equivalent to 75mm field of view. So how does this affect the 1/focal length rule? In my opinion it would be the same for both crop sensor and full frame. As all the smaller sensor does is only see the center portion of the photo. Comments?
@Carl – It sounds like we’re saying the same thing. Yes, of course it’s still a 50mm lens, but it has a 75mm EQUIVALENT focal length. It’s just semantics.
Hello Carl, I see it differently, the 50mm lens on a crop body has the equivalent view of a 75mm lens, (assuming 1.5 crop) and I agree this is due to the field of view, not a change to the lens itself, however, any movement of the lens during the exposure has the ‘equivalent’ movement of a 75mm lens as the final image is made larger from a crop sensor to achieve the same size as an image from a full frame sensor, as any movement is also magnified. As the article states, less sharp images don’t show as such when viewed small enough, only when seen larger.
I hope I’ve made sense of my own understanding, and as always, I’m happy to be wrong.
Freaken great stuff, much appreciate your time and effort on the chart and the info….thank you
Loved the article. Thank you.
Loved the article. Thank you for clearing about how this “rule” works for APS-C sensor cameras.
Thanks for taking your time to make that chart. Good article. Thanks!
The shutter speeed is usally affected by the motion or stillness of the subject in focus
Very interesting article though as far as I know only the experienced photographers can achieve the lowest shutter speeds. Generally, to avoid out of focus images I shoot at a minimum of 1/25 sec when using my 17mm lens for property photography and 1/100 sec when using my 90mm lens for portraits. Both lenses are without stabilization.
Hi there reading this on a mobile phone the inserted charts aren’t viewable?
Try using a tripod?
I like candid pic
I realize this is off subject but I am trying to correct an important photo of my sisters baby. The error was mine and the baby (mostly his face) came our real blurry and I have tried everything to try and correct it with no luck. The basket that I had the baby in, the blanket, and the background were all pretty close to perfect. I found a picture that someone else took (same age) and I want to take that other photo of just the baby and place it on top of the blurry photo (of just the baby) that I took. I tried this in light room and photo shop and for some reason I can not shrink the “better” image down to the size of the original “bad” image” and I then therefore have a near impossible time adding a layer mask. I need help. Should I try photo shop elements? (which I don’t own)? Here is what I have done so far: I opened the good/sharp photo that someone else took, I selected the portion of the photo I wanted with the lasso (over-selecting a tiny bit), then I hit edit then copy. I then went to my blurry photo and pasted the new photo to my photo (which is supposed to be my new image). In Photoshop I can not find a way to even move the object of the better photo in order to correctly place it where it needs to go, never mind making it the correct size. It’s probably do-able and I am just “missing” it but I have been trying to get this to work for two days now and I am desperate so I am hoping for an extra pair of eyes to hopefully see what I am not seeing. Thank you so very much for any help you can give me.
Some one needs to explain the physics of how a crop sensor requires higher shutter speed than a FF sensor. Here we need to restrict the comment to CAMERA/Lens movement and NOT subject movement.
And lets put aside the issue of pixel density which is a whole other issue.
Reciprocal Rule for Shutter Speed
Think of a point light source at infinity. That point rendered on a sensor of what ever size will be a function of the length of the lens (focal length) and it should make no difference if the sensor is FF or cropped. The magnification of the point on sensor will be a function of the Focal Length of the lens. The blurring due to a constant Camera/Lens motion will not change, nor will the size of the image on sensor, assuming the same lens. Or to think of it another way, If my camera has a FF and a cropped frame capability and I am using a 400mm lens, the size of the image projected on the sensor will be exactly the same. And the motion blurring due to camera/lens movement will be identical. Therefore, the Reciprocal Rule would still hold. However in a cropped image, making the same size print as from a FF, the blurring from Camera/Lens movement might be more noticeable. But that has not changed the physics. And yes, higher shutter speed is generally preferred where possible but that is to insure that what ever size image is made, it will be crisp. So, IMHO, in the last analysis, its the length (Focal Length) of the Lens, not the Sensor size that governs the rule and that applies to film ans well as digital images.
My thoughts as well. The cropping action of the sensor just reduces the border of the image. It does not ‘zoom in’ on the subject. So the same rule as for standard lenses is applicable, if a 50mm lens on a full frame sensor is crisp at 1/50″ then it will be on a crop sensor too. It is just what the term says ‘cropped’. It is not a zoom sensor.
I don’t agree. I tested this and it just doesn’t work that way. Go test it yourself and I think you’ll agree. Being cropped in on the finer details in the shot makes you notice the slight blurring more than when wider, so the crop factor DOES affect this.
I dont think you quite understood what the article is getting at. The 1/focal length for minimum shutter speed is a rule of thumb for a photo viewed at an average size to give you an image that is acceptably sharp. If you make all of your prints the same size from FF and crop, then with the crop sensor you ARE essentially zooming in. Therefore you need a different rule of thumb if you’re using a camera with a crop sensor. And the new rule of thumb would be related to the crop factor, ie: 1/(1.5 x focal length).
I accept all of your premises, but not your conclusion. Just because the lens isnt zoomed in more, doesnt mean the final picture is also not zoomed in more. eg. a full frame sensor is 35mm x 24mm to make that into a 6″x4″ print you enlarge it by 4.23 times. A canon crop sensor is 22.5mm x 15mm, to make that into a 6″x4″ you enlarge it by 6.77 times. It doesnt take a genius to work out that 6.77 is bigger than 4.23! We can think of this bigger number as being the amount of “more zoomed in” that you are, although yes I agree, the lens has not done anything and it’s not really a zoom sensor.
Or think of it another way: when you have a digital point and shoot and it does the digital zoom, everything becomes more pixellated. The digital zoom isnt zooming, it’s just cropping the image and displaying the cropped image at the same size as the original, and what happens? It becomes unacceptably blurry. The image on the sensor is exactly the same amount of blurry/sharp whether you’ve digitally cropped it or not, but the final image is blurry (pixelated) when it is cropped, the change in acceptable sharpness (or unacceptable blurriness) is related to the crop factor.
Good article.Thanks!
Does there come a point where the shutter speed is close to or faster than the IS / stabilization can handle? Perhaps even getting to a point where your high shutter speed shots are in better focus that the stabilized shots?
Sorry Paul, but you can’t correct a blur, whether it’s your camera or the subject (baby) moving. The ‘blur’ is what the camera has seen. It cannot be unseen.
I like the real-worldness of table, but as an APS-C user, it would perhaps be more clear if there was a column showing the actual lens designation and then the shutter speed row. For example, I don’t have a 32mm or 43mm lens, I have a 50 & a 35, so that’s what I need to calculate.
I was recently going through some low-light disappointments only to finally realize after 12 months ownership, that Nikon’s 35 or 50mm don’t have VR ! (I just took it for granted as it’s on my 18-55 & 18-200) I’m now trying and shoot at double the focal length to be super safe. I’ve set the camera to use that minimum and bump the ISO automatically if necessary.
Very nice, thanks.
Of course, we’re assuming that we’re using a SLR, aren’t we, where we have to deal with a fairly large mirror slapping up just before the exposure is made and jarring everything?
Even at my advanced age, I feel pretty comfortable using 1/30, and sometimes 1/15 with a 5cm lens on my rangefinders (old Leicas or my Canon P).
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I agree with Sundial. One could crop a full frame image in pp to a crop size without affecting sharpness. That is all an APC camera does. What if one uses a 4×5 frame camera ?
Two different concepts of image sharpness. The actual sharpness and the perceived sharpness.
Actual sharpness refers to the sharpness or the lack of it on the original image file. This can be inspected ON A COMPUTER DISPLAY at 1:1 pixel or more.
Perceived sharpness refers to the impression on the final output images that has a certain intended size appropriate for the intended viewers. Hard prints, web use,…. etc.
Focal length amplifies camera shake recorded on the sensor, therefore affects the Acutal Sharpness. One other factor is the pixel size, for example D700 8.4micron & D810 4.8micron. The smaller pixel size “sees” more details of the view thus also “sees” more camera shake if exists. (Pixel image scale in arcsec = 406 x pixel size in micron / focal length in mm) This is the angular size that a single pixel sees.
Focal length & Pixel size determine actual image sharpnessat the sensor level.
Crop factor doesn’t amplify camera shake, but amplifies any blurriness (lack of actual sharpness) that is already in the image (unless 100% actual sharpness) when enlarging to same large print size.
Crop factor determines the perceived image sharpness at the print/display level.
An excellent explanation Samual.