5 causes of blurry photos and how to deal with it | Articles | Photo, video, optics

Pho­to: stocksnap.io

You take an impor­tant shot, but it turns out to be blur­ry … It’s good when you have the oppor­tu­ni­ty to take anoth­er shot, but it also hap­pens that the moment is irre­triev­ably lost. Imag­ine how hurt­ful it can be if you are film­ing the first steps of a child or any oth­er event that will nev­er hap­pen again. So why are blur­ry pho­tos and how to avoid it?

Blurred photo due to long exposure

Shak­ing is pos­si­ble under dif­fer­ent cir­cum­stances, but most often it’s a slow shut­ter speed. It is she who is the most com­mon cause of blur­ry frames. In this case, vibra­tions of the cam­era itself can be insignif­i­cant and even imper­cep­ti­ble. The min­i­mum shake appears already at a shut­ter speed of more than 1/60 sec­ond, although a lot depends on the lev­el of sta­bi­liza­tion of the cam­era and the expe­ri­ence of the pho­tog­ra­ph­er.

The solu­tion is sim­ple: to get a sharp image, short­en the shut­ter speed. For dif­fer­ent focal lengths, cer­tain val­ues ​​\u200b\u200bof this para­me­ter are suit­able for hand­held shoot­ing. More details about expo­sure will be dis­cussed below.

A tri­pod is indis­pens­able when pho­tograph­ing land­scapes, but it is most often use­less for shoot­ing mov­ing objects. Pho­to: stocksnap.io

Anoth­er way to solve the shake prob­lem is to use a tri­pod.. But even with it, fluc­tu­a­tions are pos­si­ble, for exam­ple, with strong gusts of wind. In this case, many tri­pod mod­els are equipped with a spe­cial hook for hang­ing loads (usu­al­ly even a back­pack with pho­to­graph­ic equip­ment is enough). Unfor­tu­nate­ly, a tri­pod at slow shut­ter speeds is use­less if there are mov­ing objects in the frame. So we smooth­ly approached the next com­mon cause of blur­ry pic­tures.

Moving object = blurry photo

Mov­ing sub­jects are always hard­er to shoot than sta­t­ic ones. Due to the rapid change in com­po­si­tion, the frames are blur­ry, and the longer the shut­ter speed, the more deplorable the result. In such sit­u­a­tions, even a tri­pod does not save. The built-in sta­bi­liza­tion func­tion helps a bit, for­giv­ing minor mis­takes by the pho­tog­ra­ph­er and allow­ing you to set the shut­ter speed a lit­tle longer. A suit­able val­ue has to be select­ed tak­ing into account the cir­cum­stances and the object being filmed. Here are the basic shut­ter speed para­me­ters that you can build on:

— when shoot­ing a sta­tion­ary object, shut­ter speeds up to 1/60 s are suf­fi­cient;
— if you are pho­tograph­ing chil­dren, you need a shut­ter speed of 1/200 s or even short­er;
— when it is nec­es­sary to “freeze” the move­ment of an ath­lete or a car in a race, a shut­ter speed of no longer than 1/500 s is required.

There is also one sim­ple for­mu­la that will help you nav­i­gate when set­ting shut­ter speed: fastest shut­ter speed = 1 / focal length. Accord­ing­ly, on a 200 mm tele­pho­to lens, the shut­ter speed should not be longer than 1/200. You also need to learn how to smooth­ly press the shut­ter when tak­ing pic­tures with your hands.

The longer the shut­ter speed, the more blurred mov­ing objects are. Pho­to: wikimedia.org

Mod­ern cam­eras for shoot­ing mov­ing sub­jects have track­ing aut­o­fo­cus, which antic­i­pates the move­ment of the sub­ject and focus­es on it with­out los­ing sight. Nikon and Pen­tax cam­eras call this fea­ture AI Ser­vo AF or AF‑C, while Canon calls it Auto Select.

DOF and blurry shots

DOF stands for Depth of Field. In oth­er words, just depth of field. When it is not enough, the pic­tures are blur­ry. Let’s explain with an exam­ple: if you have an 18–55mm whale lens, at f / 5.6 the depth of field will be about 7 cm at the long end, and the sub­ject will be in focus at a dis­tance of about 1 meter. Every­thing that will be locat­ed out­side the depth of field will turn out to be blur­ry.

Such blur­ring is often expe­ri­enced by peo­ple shoot­ing with a smart­phone or com­pact dig­i­tal cam­eras, which have high depth of field and all objects are in the sharp­ness zone. The larg­er the sen­sor, the low­er the depth of field. This gives the pic­tures vol­ume by blur­ring the back­ground.

Prop­er­ly set using the aper­ture depth of field helps to cre­ate clear­er pic­tures by blur­ring the back­ground. Pho­to: flickr.com

If you are shoot­ing with sin­gle point focus, you may expe­ri­ence blur­ry pho­tos. It is caused by an aut­o­fo­cus error or slight move­ment of the cam­era or sub­ject. The depth of field in this case also shifts, and the frame turns out to be blur­ry.

There are sev­er­al ways to avoid this prob­lem:

— man­u­al­ly spec­i­fy the focus point (but this is incon­ve­nient);
— do not rotate the cam­era, but shift it only par­al­lel to the plane of the object being filmed;
— use man­u­al focus;
— increase the depth of field by clos­ing the aper­ture (in this case, the back­ground will be blurred less).

Why are all photos blurry in the dark?

It is more dif­fi­cult for any cam­era to focus in a dark space if it does not have an expen­sive fast lens attached to it. In oth­er cas­es, every­thing works like this: due to the lack of light, the shut­ter speed becomes longer, and the pho­to turns out to be blur­ry. There are sev­er­al solu­tions to the sit­u­a­tion, and they can be used in com­bi­na­tion:

— Add light. There are many ways, the choice depends on the cir­cum­stances. You can either move the sub­ject clos­er to the light source, or turn on the aut­o­fo­cus assist func­tion in the cam­era (it only works at short dis­tances), or use the flash, and so on.
— Increase ISO and open aper­ture wider. When shoot­ing in auto­mat­ic mode, only ISO sen­si­tiv­i­ty is usu­al­ly adjust­ed, and the aper­ture can­not be con­trolled — you will have to switch to man­u­al mode.
— Use a tri­pod or place the cam­era on a sta­t­ic sur­face. In such cas­es, the pho­to will turn out sharp at any shut­ter speed, pro­vid­ed that the objects in the frame are still.

A typ­i­cal exam­ple of a night pho­to with insuf­fi­cient ISO and a slow shut­ter speed. Pho­to: flickr.com

Weather and blurry shots — what’s the connection

There was one non-obvi­ous rea­son for blur­ry pho­tos — it would seem, how can weath­er con­di­tions affect the focus of the cam­era? In fact, they can, and some­times very sig­nif­i­cant­ly. The prob­lem man­i­fests itself main­ly when shoot­ing dis­tant sub­jects, so if you spe­cial­ize in por­traits, you may nev­er have encoun­tered this.

So, if the air is filled with dif­fer­ent par­ti­cles (there is a fog, it’s rain­ing light­ly, or it’s haze from the heat out­side), they can pre­vent you from achiev­ing per­fect sharp­ness. We have no con­trol over these cir­cum­stances. You can try to “play” with the set­tings by set­ting dif­fer­ent shut­ter speed, ISO and aper­ture val­ues, or sim­ply resched­ule shoot­ing to anoth­er day, if pos­si­ble.

More reasons why your photos always come out blurry

There are oth­er fac­tors that can affect qual­i­ty. Blurred pho­tos can be obtained if:

— The sub­ject is too close. Each lens has a min­i­mum focus­ing dis­tance. For exam­ple, tele­pho­to lens­es focus on sub­jects at least two meters away.
— The lens is dusty. Keep the lens clean and wipe it peri­od­i­cal­ly.
— Poor qual­i­ty (or worn out from time) light fil­ter.
— Cheap kit lens. Although even they can get good shots with prop­er skill.

To get a sharp image in the pic­tures, prac­tice more by ana­lyz­ing your mis­takes. And remem­ber that even the pros make mis­takes some­times, so each shoot starts with a few sight­ing shots to assess the sit­u­a­tion.