Why photos are blurry and how to get rid of it once and for all | Articles | Photo, video, optics

Blur­ry pho­tos, fuzzy pho­tos, blur­ry pho­tos — if you’ve ever picked up some­thing that can take pic­tures, you’ve prob­a­bly encoun­tered this prob­lem. And it becomes a prob­lem in the square, because often the advice on com­bat­ing lubri­ca­tion con­tra­dicts each oth­er. The fact is that blur­ring (unsharp­ness, fuzzi­ness) has at least 7 rea­sons. And you will have to fight them in 7 dif­fer­ent ways. We under­stand all the sub­tleties in this mate­r­i­al.

Some­times grease can look beau­ti­ful. But not always / Pho­to: unsplash.com

Blur­ry pho­tos when cap­tur­ing motion
What to do if there is nowhere to short­en the shut­ter speed
Blurred pho­tos due to hand move­ment or shake
The clas­sic focus error
Trou­ble focus­ing in the dark
Focus prob­lems due to the move­ment of the sub­ject towards the cam­era
Insuf­fi­cient depth of field
What lubri­cants indi­cate lens fail­ure

In one com­ment thread in a group ded­i­cat­ed to pho­tog­ra­phy, I saw a won­der­ful (and very typ­i­cal) dis­cus­sion. In short, its essence:

- I shoot cor­po­rate par­ties indoors on a junior DSLR. Pho­tos are blur­ry, help!

What is the aper­ture?

- 1.4

- This is all because you have a small DOF. Close until 8 and you will be hap­py.

- I tried. It got even worse. They were a lit­tle blur­ry, they became com­plete­ly smeared. I screwed up the shoot.

Well, I don’t know then. It helps me.

And the prob­lem of blur­ry pho­tos for a begin­ner, and advice, and the fact that it does not help — every­thing is extreme­ly typ­i­cal here. The first prob­lem is that under the word “unsharp” a per­son with lit­tle expe­ri­ence can hide var­i­ous prob­lems. The sec­ond is that lubri­ca­tion can be very dif­fer­ent. And you need to deal with them in dif­fer­ent ways. And a closed aper­ture can only help fight two types of prob­lems. And then, this is not the best method. Let’s talk about every­thing in order.

Blur on the left, under­fo­cus on the right. And these are com­plete­ly dif­fer­ent things / Pho­to: unsplash.com

Motion blur is a very com­mon prob­lem. It occurs when you shoot some­thing rel­a­tive­ly mov­ing: a danc­ing cou­ple, chil­dren play­ing, a cat run­ning, cars dri­ving along the road.

It looks some­thing like this: a mov­ing object (or indi­vid­ual parts of it, for exam­ple, hands) are blurred, every­thing else is rel­a­tive­ly clear

The girl’s face is clear, her hand was smeared from fast move­ment / Pho­to: unsplash.com

The only way to deal with motion blur is to select the cor­rect shut­ter speed. The longest shut­ter speed you should use:

• for a sta­t­i­cal­ly pos­ing group of peo­ple — 1/30 (be care­ful, hand move­ment may be blurred, about it in the next sec­tion);
• for slow move­ment (yoga, calm walk­ing) — 1/100;
• for fast move­ment (run­ning, ani­mals, chil­dren play­ing) — 1/500;
• for very fast move­ment (pro­fes­sion­al sports, cars, etc.) — 1/1000.

In terms of shut­ter speed con­trol, it’s best to shoot in shut­ter pri­or­i­ty mode (Tv or S depend­ing on the sys­tem).

Let’s say you’re shoot­ing a danc­ing cou­ple in a dark room. For exam­ple, at a wed­ding or cor­po­rate par­ty. The para­me­ters at which the pho­to turns out to be nor­mal­ly exposed, for exam­ple, are: F 2.8, ISO 800, 1/100.

Objec­tive­ly, weav­ing is not enough for shoot­ing a dance, espe­cial­ly a fast one. In a good way, you need 1/250 or 1/500. To get an over­ex­posed frame at such shut­ter speeds, you will either have to raise the ISO or open the aper­ture.

If the aper­ture val­ue is already the lim­it (a nor­mal sto­ry for a bud­get kit lens), only ISO remains. But if the cam­era is as bud­get as the lens, a lot of noise will already go to ISO 1600. And even more so at 3200. You may encounter such prob­lems if you shoot, for exam­ple, on the Nikon D5300, but if you have a Canon EOS 5D Mark IV, then it will cope with such a scene with­out any prob­lems sim­ply due to high­er work­ing ISO.

But what if you have a bud­get cam­era? Either shoot with a flash, or put up with the fact that this sto­ry can­not be shot on this cam­era in any way.

By the way, in this sit­u­a­tion, the pro­pos­al to close the aper­ture to 8 will just kill the shoot­ing: close to 8, the shut­ter speed is extend­ed to 1/15. We get a stronger motion blur, and more motion blur of the hands.

Or alter­na­tive­ly: the shut­ter speed remains the same, and the ISO flies into space, ris­ing to 6400, pro­vok­ing strong nois­es. In any case, the shoot­ing is leaked.

It also comes from move­ment. But from the move­ment of the hands of the pho­tog­ra­ph­er. May appear in and in shots of run­ning chil­dren and land­scape shots.

It looks like this. The whole pic­ture is fair­ly even­ly smeared / Pho­to: Alisa Smirno­va, Fotosklad.Expert

To solve this prob­lem, we return to expo­sure again. There is a for­mu­la that helps to cal­cu­late the shut­ter speed at which there should be no blur­ring of hand move­ment. This for­mu­la can be found in absolute­ly every text about blur­ry pho­tos. There she is:

Fastest shut­ter speed = 1 / lens focal length

If the for­mu­la is dif­fi­cult, do not wor­ry. Still, it is absolute­ly accu­rate and use­ful only if you are shoot­ing with a 1960 Zenith. First­ly, because the for­mu­la was devel­oped in the days of film cam­eras, the cal­cu­la­tion is car­ried out for film cam­eras, which did not have the high­est sharp­ness com­pared to mod­ern dig­i­tal ones. For exam­ple, tests show that on matri­ces larg­er than 40 megapix­els (Sony Alpha A7R IIIA), the shut­ter speeds rec­om­mend­ed by this for­mu­la pro­vide micro-lubri­ca­tion. And a good result is achieved at shut­ter speeds twice as short.

Sec­ond­ly, because in 2022 you still need to make adjust­ments for what kind of cam­era and lens you have. If you have a sta­bi­lized lens or cam­era (for exam­ple, Fuji­film X‑T4 and Nikon 18–140 mm), then on the con­trary, you can not blur longer expo­sures (3–4 times).

And if both are sta­bi­lized, then there are already two vari­ables in this equa­tion.

It’s all fun math. But in essence, to solve the prob­lem, you need to fig­ure out what kind of shut­ter speed you are hold­ing on your par­tic­u­lar equip­ment, and which one you are smear­ing. You can cal­cu­late by for­mu­las, but it is bet­ter to con­duct an exper­i­ment. Put your cam­era in shut­ter pri­or­i­ty mode and take a few shots at val­ues ​​between 1/500 and 1/30. Then look on the big screen where the blur val­ue starts. At shut­ter speeds longer than hand-held, it is bet­ter not to shoot.

It is also worth remem­ber­ing about the human fac­tor: if at home, for exam­ple, you calm­ly keep 1/50, on respon­si­ble shoot­ing, when you are ner­vous, you can smudge it. On such shoot­ings, it is bet­ter to work at slight­ly faster shut­ter speeds.

It’s also use­ful to look at old footage, find blur­ry pic­tures and find out what the shut­ter speed was. Most pic­tures from most cam­eras store all the data about the shoot­ing para­me­ters. You can view them using a stan­dard Win­dows brows­er.

In order for the right pan­el to appear, you need to click on the Details pane icon / Details pan­el / Illus­tra­tion: Alisa Smirno­va, Photosklad.Expert

As a rule, the min­i­mum shut­ter speed, on which there is no blur, for dif­fer­ent peo­ple is in the range from 1/30 to 1/200. It depends on the tech­nique (sta­bi­lized cam­eras and lens­es help to keep longer expo­sures), and on skills.

Here you can go in two ways: either short­en the shut­ter speed (just as in the case of blur­ring the move­ment of an object), or learn to shoot at slow­er shut­ter speeds.

What can help to shoot with­out blur­ring at slow­er shut­ter speeds:

- Tri­pod or mono­pod. If you shoot sta­t­ic (land­scape, still life, evening por­trait of an adult who is able to stand still), God him­self ordered to use some­thing sim­i­lar. You can read about how to work with a mono­pod here. If you don’t have a tri­pod, but you need to shoot, look for any kind of hand sup­port. Rest your elbows on the table, lean against the wall. All this will help to min­i­mize shak­ing a lit­tle.

- Cor­rect cam­era grip. It’s easy to blur a pho­to if you take it with your arms out­stretched above your head. There are prop­er grips that help min­i­mize cam­era shake when tak­ing a pic­ture. The most com­mon grip looks like the pho­to below.

The right hand holds the cam­era, the left hand secure­ly sup­ports the lens from below. The cam­era itself is pressed to the face, because of this it can­not swing back and forth. Elbows pressed to the body / Pho­to: photographylife.com

And remem­ber that the posi­tion of the whole body will help min­i­mize shak­ing. To do this, spread your legs, stand upright and lean for­ward a lit­tle. This pose is opti­mal so that the pho­tos are not smeared.

A more exot­ic ver­sion with sup­port on your own shoul­der / Pho­to: expertphotography.com

- Ser­i­al shoot­ing. If you see that the shut­ter speed is too long, but you need to shoot, take not one shot, but a long series. Most often, hand move­ments that cause blur­ring occur pre­cise­ly at the moment the shut­ter but­ton is pressed. In a series, the first two shots may be blur­ry, while the next two shots have a chance of being sharp. How­ev­er, remem­ber that this trick only helps when shoot­ing sta­t­ic.

Some­times the prob­lem is that the author of the pic­ture sim­ply did not get into focus when shoot­ing with a rel­a­tive­ly fast lens. And the result looks like this:

Some­times this tech­nique is used con­scious­ly to show that the main char­ac­ter of the frame is not a per­son, but a land­scape. But some­times a mis­take is just a mis­take / Pho­to: unsplash.com

When does this hap­pen? Sup­pose a per­son has been shoot­ing with a whale lens for sev­er­al years, and in prin­ci­ple does not have the habit of focus­ing. He has a min­i­mum aper­ture val­ue of 4. And the per­son is also a big fan of auto aper­ture, which clos­es this 4 to 8. The focus point dan­gles some­where in the upper left side of the screen, but on a closed aper­ture, sharp­ness is still all over the frame, so there is no habit of focus­ing does not inter­fere with life.

A per­son decides to buy a por­trait fifty kopeck for 1.4 and try to work with it. And with it, you already need to make sure that the focus­ing point is exact­ly on the area of ​​​​the model’s eyes, and not on the ear, not on the arm, not on the wall behind her back. And there is no habit of focus­ing. Hence the errors. Some­times every­thing does not look as scary as in the pic­ture above, but for exam­ple, like this:

Here the sharp­ness is not in front of the eyes, but on the bou­quet in the hands of the girl. Such a pic­ture can, in prin­ci­ple, not be con­sid­ered a mar­riage, although, of course, there is an error in focus / Pho­to: Alisa Smirno­va, Photosklad.Expert

The pic­ture above is a great illus­tra­tion of the prob­lem of under­fo­cus due to dark­ness. The fact is that some­times inex­pen­sive bright lens­es focus slow­ly. If a whale lens is focused in a frac­tion of a sec­ond, a light lens in dif­fi­cult con­di­tions can fid­get back and forth for sev­er­al sec­onds and even­tu­al­ly focus in an incom­pre­hen­si­ble place. Or just don’t focus.

Such a pic­ture can be eas­i­ly obtained in dif­fi­cult light con­di­tions / Pho­to: unsplash.com

And it does­n’t have to be total dark­ness. Also bad con­di­tions for focus­ing will be:

• back­light (por­trait at sun­set, when the sun is in the back);
• con­stant­ly chang­ing, flick­er­ing light (danc­ing at a wed­ding with strobe lights).

Here is just shoot­ing in the back. The girl’s face is illu­mi­nat­ed by a flash that fires as soon as the shut­ter is released. At the moment of focus­ing, it was in sol­id shad­ow. The focus fid­get­ed and set­tled on the bou­quet, which is illu­mi­nat­ed by a gar­land (con­stant light) between the branch­es.

How to deal with under­fo­cus due to dark­ness:

• Use aut­o­fo­cus illu­mi­na­tor. If not, any flash­light will do. More­over, if addi­tion­al light spoils the atmos­phere of the frame for you, you can use it only at the moment of focus­ing. We illu­mi­nat­ed the hero’s face with a flash­light, focused by half-press­ing the shut­ter but­ton, with­out releas­ing it, turned off the flash­light, and took a pic­ture.
• Remem­ber that any trick loves con­trast: it’s eas­i­er to focus on the bor­der of the eye if it’s a large por­trait, the bor­der of skin and dark clothes if it’s full-length. If the focus­ing point is exact­ly in the mid­dle of the abdomen of a per­son in a black T‑shirt, it will be more dif­fi­cult to focus.

This prob­lem occurs when shoot­ing mov­ing sub­jects (such as sports or chil­dren play­ing). And, as a rule, on lens­es with a small depth of field.

The ath­lete in the fore­ground jumped out of the field of focus / Pho­to: Alisa Smirno­va, Photosklad.Expert

It hap­pens like this: you focus, after a few frac­tions of a sec­ond you take a pic­ture, but in these frac­tions of a sec­ond the per­son has already man­aged to run out of the depth of field.

This prob­lem is solved by using con­tin­u­ous aut­o­fo­cus (in most AF‑C or C‑AF sys­tems).

Mov­ing on from blur­ring to issues relat­ed to focus. The prob­lem of insuf­fi­cient depth of field (depth of field of the depict­ed space) is liked by all lovers of Sovi­et text­books and for­mu­las suit­able for Zenith. This is where they give advice to close the aper­ture to 8.

F 1.4 on the left, F 8 on the right. Yes, the pot in the left pic­ture is blur­ry, but on the right we com­plete­ly lost the beau­ti­ful back­ground. The advice to close works so-so / Pho­to: Alisa Smirno­va, Photosklad.Expert

In fact, in the mod­ern world, this prob­lem is rather rare. Most often, insuf­fi­cient depth of field inter­feres either with sub­ject shoot­ing or when shoot­ing land­scapes. You can read about how to get both a sharp pot and a blur­ry back­ground here.

Or else there is a fre­quent sit­u­a­tion when shoot­ing groups of peo­ple. For exam­ple, we shoot a large or chest por­trait of a cou­ple, where one per­son stands behind the oth­er’s shoul­der.

The moth­er’s eyes are com­plete­ly sharp, the daugh­ter’s face is already blurred. Aper­ture val­ue — 1.4 / Pho­to: Alisa Smirno­va, Fotosklad.Expert

In this case, you can real­ly cov­er the aper­ture to 4, and the prob­lem will dis­ap­pear. The only point is that at F4 you will lose the back­ground blur and beau­ti­ful bokeh from the Christ­mas tree gar­land. It will be like in the pho­to with the pot above. That is, clos­ing the aper­ture will go as an emer­gency mea­sure that will help save the frame, but def­i­nite­ly not suit­able as a long-term strat­e­gy.

The prob­lem here is that the lens real­ly does not have too much depth of field. To be pre­cise, from this dis­tance, this par­tic­u­lar lens has a depth of field of about 10 cen­time­ters. And for such a dou­ble por­trait, it turned out to be not enough.

What can be done here:

First, try to place peo­ple in approx­i­mate­ly the same line. Let’s look at anoth­er pic­ture from this series.

The daugh­ter sat down next to her moth­er, and not behind her shoul­der there are no prob­lems in focus / Pho­to: Alisa Smirno­va, Photosklad.Expert

Sec­ond­ly, it is worth get­ting to know your equip­ment in detail and under­stand­ing what kind of depth of field each lens has in which por­traits. There is a good ser­vice that sim­u­lates dif­fer­ent depth of field on dif­fer­ent cam­eras.

Here you can select a spe­cif­ic cam­era and lens mod­el, select the dis­tance to the mod­el in the low­er menu, and here on the right the sim­u­la­tor will show the depth of field for these spe­cif­ic para­me­ters / Illus­tra­tion: Alisa Smirno­va, Fotosklad.Expert

With it, we can see what the depth of field will be if you shoot a half-length por­trait on a full-frame DSLR on a Canon EF 50mm f / 1.4. The depth of field will be 8 cen­time­ters, which is accept­able for a half-length por­trait.

If you click on the mag­ni­fy­ing glass above the fig­ure, it will turn in pro­file and we will see the depth of field clear­ly. Here, in sharp­ness, the entire face is almost up to the ears, which is accept­able / Illus­tra­tion: Alisa Smirno­va, Photosklad.Expert

But shoot­ing a group half-length por­trait (for exam­ple, at a bach­e­lorette par­ty) with a sim­i­lar lens with an open aper­ture is no longer worth it. Three girls will not stand in a per­fect­ly straight line, some­one will hug a friend from behind and get the same prob­lem that the first New Year’s por­trait had.

Some­times it hap­pens that not incor­rect set­tings, not dif­fi­cult shoot­ing con­di­tions, but faulty equip­ment are to blame for the blur. A super char­ac­ter­is­tic exam­ple, which was shot on a bud­get Fuji­film XC 50–230. The lens has a plas­tic body, it is easy to dam­age it, it was no longer new at the time of shoot­ing, and gave out such a pic­ture.

Pay atten­tion to the details: the entire right edge is smeared even­ly. Sharp­ness on ski­er #201, and #286 looks smudged / Illus­tra­tion: Alisa Smirno­va, Photosklad.Expert

One could chalk it up to insuf­fi­cient depth of field, but ski­er #260 is fur­ther from the cam­era than #286, and if there was a prob­lem with depth of field, it would be more blur­ry. More­over, com­pare the nature of the blur. Ski­er #260 goes into blur, and ski­er #286 is blur­ry. It would be pos­si­ble to attribute every­thing to motion blur, but the shut­ter speed in this pic­ture is 1/250. Skiers go uphill, go slow­ly, such expo­sure is more than enough.

Anoth­er impor­tant sign of such a blur: pho­tos are always blur­ry. The blur will be repeat­ed from frame to frame, con­stant­ly appear­ing in the same place. No mat­ter what scene you are shoot­ing, no mat­ter where the focus is and what the shut­ter speed is. There is noth­ing you can do about such a prob­lem: you need to car­ry the equip­ment for repair or change it to a new one.

The next frame from the same shoot­ing: the right side of the ski­er is clear, the left shoul­der and head, which fall into the prob­lem area, are under­mined. The inscrip­tion on the side is read­able per­fect­ly, the coat of arms is already indis­tin­guish­able / Illus­tra­tion: Alisa Smirno­va, Photosklad.Expert

How­ev­er, if you see this in your pic­tures, do not rush to pan­ic. First, check if the front and rear lens­es are dirty. Some­times dirt on them gives a sim­i­lar effect. If dirty — wipe, if clean — then in the ser­vice.