Camera Shake in Handheld Photography

How to deal with handheld camera shake

Whether your goal is to freeze fast action or to take a sharp pho­to of a rel­a­tive­ly sta­t­ic scene (such as a land­scape or fam­i­ly por­trait), it’s help­ful to under­stand that motion blur has two dis­tinct types:

• blur­ring caused by fast sub­ject move­ment
• blur­ring caused by move­ment of the cam­era

Motion blur caused by move­ment of an unsta­ble cam­era is com­mon­ly called cam­era shake and is dis­tin­guished by the fact that it affects every part of the com­po­si­tion equal­ly. Cam­era shake is most often asso­ci­at­ed with hand­held pho­tog­ra­phy. Your breath­ing, heart­beat, and mus­cle tone all con­tribute to some indi­vid­ual base lev­el of unsteadi­ness, in addi­tion to the vibra­tions caused by mir­ror and shut­ter shock. Thus, when tak­ing a hand­held pic­ture, the cam­era is always slight­ly unsteady.

The amount and pres­ence of cam­era shake in your pho­tos are deter­mined by your shut­ter speed and focal length. Focal length is a sig­nif­i­cant fac­tor in cam­era shake because nar­row­er angles of view mag­ni­fy the motion of your cam­era as its view wavers across the scene. Shut­ter speed is a fac­tor because it can either cap­ture a short­er or longer peri­od of that motion. In gen­er­al, you’re less like­ly to notice cam­era shake when using a faster shut­ter speed and short­er lens focal length, and you’re more like­ly to notice cam­era shake when using a slow­er shut­ter speed and longer lens focal length. The min­i­mum shut­ter speed for­mu­la describes the slow­est shut­ter speed and focal length com­bi­na­tion that you can use while safe­ly avoid­ing motion blur caused by cam­era shake:

1/(effective focal length)

Using this for­mu­la, you can deter­mine that a 200 mm lens can be used at a shut­ter speed of 1/200 sec­ond, a 50 mm lens at 1/50 sec­ond, a 24 mm lens at 1/25 mm, and so on. In sit­u­a­tions where the rec­i­p­ro­cal of your focal length does­n’t have a cor­re­spond­ing shut­ter speed, select the next fastest one. If your cam­era has a very high-res­o­lu­tion image sen­sor, or if you intend to make huge prints, con­sid­er­ing alter­ing the for­mu­la in the fol­low­ing way to ensure clear results:

1/((effective focal length) × 2)

Camera shake and image stabilization

Image sta­bi­liza­tion, or IS, is an umbrel­la term for tech­niques that reduce the motion blur asso­ci­at­ed with cam­era shake. IS goes by dif­fer­ent names depend­ing on the man­u­fac­tur­er of the cam­era: Image Sta­bi­liz­er (IS) by Canon, Vibra­tion Reduc­tion (VR) by Nikon, Opti­cal Image Sta­bi­liza­tion (OIS) by Fuji­film, Image Sta­bi­liza­tion (IS) by Olym­pus, MegaOIS by Pana­son­ic, Opti­cal Steady Shot (OSS) by Sony, Shake Reduc­tion (SR) by Pen­tax, and so on. Regard­less of brand­ing, there are two main cat­e­gories of OIS, lens-based image sta­bi­liza­tion and sen­sor-shift image sta­bi­liza­tion.

Lens-based or opti­cal image sta­bi­liz­ers (OIS) employ a float­ing lens ele­ment that moves per­pen­dic­u­lar to the opti­cal axis (the straight line through the lens cen­tre) to com­pen­sate for angu­lar move­ment and vibra­tions detect­ed by a pair of accelerom­e­ters. Lens­es with OIS are more com­pli­cat­ed and expen­sive than sim­i­lar mod­els with­out it. The main advan­tage of OIS sys­tems is that the image pro­ject­ed into the viewfind­er of SLR cam­eras is also sta­bi­lized, which aids accu­rate fram­ing.

In sen­sor-shift or in-body image sta­bi­liza­tion (IBIS), the image sen­sor is mount­ed on a mov­ing plat­form pow­ered by an actu­a­tor that com­pen­sates for the move­ment and vibra­tions detect­ed by accelerom­e­ters in the cam­era body. IBIS keeps the image sen­sor aligned to a fixed point in the pro­ject­ed image by pre­cise­ly mea­sur­ing the angu­lar and rota­tion­al veloc­i­ties induced by cam­era shake. This is com­pli­cat­ed because the sys­tem must tai­lor the com­pen­sa­tion degree to match each lens’s focal length. The main advan­tage of in-body image sta­bi­liza­tion is that they work with unsta­bi­lized lens­es, includ­ing a poten­tial­ly huge archive of vin­tage lens­es, so long as their image cir­cles are large enough to accom­mo­date the image sen­sor’s cor­rec­tive move­ments.

Man­u­fac­tur­ers mea­sure the effec­tive­ness of both types of image-sta­bi­liz­ing sys­tems using pho­to­graph­ic stops. Stops of sta­bi­liza­tion describe how many stops slow­er you can safe­ly set your shut­ter speed in com­par­i­son to that pre­scribed by the min­i­mum shut­ter speed for­mu­la for your focal length. For exam­ple, if you’re using a 200 mm lens and your OIS sys­tem offers three stops of sta­bi­liza­tion, you should be able to take pic­tures at a shut­ter speed of 1/25 sec­ond safe­ly ((1/200)×2^3)=1/25).