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Photography transcript 6 — Exposure in photography — Photography.ca

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Please note that this is an audio tran­scrip­tion. Gram­mer and punc­tu­a­tion will not be per­fect.Hi there every­one and wel­come to the Pho­tog­ra­phy Pod­cast on Photography.ca.‚ My name Marko and we are com­ing to you from Mon­real, Que­bec, Canada, and today is Decem­ber 8, 2006.
For today’s show, we are going to talk about expo­sure.‚ Although a lot of peo­ple know about expo­sure, a lot of peo­ple do not.‚ Some­one on the bul­letin board men­tioned that they like to know a lit­tle bit more about get­ting good expo­sure, so I thought I talk about that today.‚ Even if you know about it, I guess you can hear about it again and we all learn from each other’s tech­niques.‚ It is a good thing to do.
Expo­sure refers to the quan­tity of light hit­ting the film or dig­i­tal sen­sor, in terms of a dig­i­tal cam­era, to cor­rectly take the shot.‚ This quan­tity of light, it needs to be pre­cise.‚ If too much light hits the film or sen­sor, the shot will be over­ex­posed or too light.‚ If not enough light hits the dig­i­tal sen­sor or film, then the shot will be too dark and it will be under exposed.‚ It really needs some pre­ci­sion.‚ The good news is, is that in today’s mod­ern cam­eras either tra­di­tional cam­eras or dig­i­tal cam­eras, the sen­sor in that cam­era is very sophis­ti­cated.‚ Gen­er­ally, that sen­sor will give you good results most of the time.‚ Under nor­mal cir­cum­stances when there is good mix­ture of tones in the scene, your shot will be cor­rectly exposed because basi­cally what the cam­era sen­sor is try­ing to do, it is try­ing to give an aver­age read­ing of all the tones in the scene.‚ If you have a lot of dark tones and a lot of light tones and some mixed tones, well, then your cam­era will gen­er­ally give you very good expo­sure and that is all you need to do.‚ The prob­lems hap­pen when there is too much of one tone or too much of another tone.‚ Specif­i­cally, if there is too many light tones or too many dark tones, what the cam­era is going to try and do and say, “Hey look at those light tones com­ing to the cam­era.‚ In order for me to make this aver­age, I need to close down a bit.”‚ What is going to hap­pen is your shot is going to look grayer or not as light as it should.‚ These are sit­u­a­tions where you need to be care­ful.‚ There are other tech­niques that you can use that will help solve these sit­u­a­tions.
The clas­sic exam­ple, of course, is some­one stand­ing in front of beach or in front of a win­dow and then another per­son tries to take a pho­to­graph of that.‚ When that cam­era is look­ing at the scene, it is say­ing, “Oh my good­ness, look at all the light com­ing into the cam­era.‚ Again, I need to shut down.”‚ What hap­pens is the per­son in front of the beach or the win­dow ends up look­ing too dark because the cam­era under­ex­posed the sub­ject because so much light was com­ing into the cam­era.‚ These are the sit­u­a­tions where you have to be care­ful.‚ When you see extreme amounts of light com­ing into the cam­era or on the oppo­site end, if you are tak­ing a pic­ture of, let us say, some­one wear­ing dark clothes against the dark wall, the cam­era is going to say, “Oh my god, this scene is so dark.‚ I need to aver­age it out.‚ I need to open up a lot.‚ I need to give the shot more expo­sure.”‚ What hap­pens is the black per­son in the black suit against the black wall ends up turn­ing out mushy and not black because the cam­era did not cor­rectly expose for those tones.‚ Like I said, again, to recap, in nor­mal scenes where there is a vari­ety of tones, there is really no prob­lem and you will gen­er­ally get good expo­sure.‚ The trick is being able to notice when the scene is not nor­mal.‚ That only comes with expe­ri­ence.‚ Of course, if you have a dig­i­tal cam­era, you could just look at the results and adjust expose accord­ingly and hope­fully learn from it or if you are with a con­ven­tional cam­era, take notes if you are learn­ing and then when you get back the results you can also see what went right and what went wrong.
Now, the cam­era sen­sor in your cam­era, that is a reflec­tive sen­sor.‚ That is reflec­tive meter.‚ It is called reflec­tive meter because it mea­sures the light that is hit­ting your sub­ject and com­ing back to the cam­era, the light that is being reflected back to the cam­era.‚ These are gen­er­ally excel­lent in qual­ity as we men­tioned before espe­cially in mod­ern cam­eras.‚ Again, you just have to be aware of the sit­u­a­tion where the light­ing is not nor­mal because that cam­era meter will be fooled.‚ What these reflec­tive meters do when they are in cam­era is they aver­age out the whole scene within the cam­era.‚ It looks at the whole scene and the cam­era mea­sures the whole scene.
There is another type of reflec­tive meter called the spot meter.‚ It is exactly the same in prin­ci­ple except that it only mea­sures a smaller area of the pho­to­graph.‚ Usu­ally, you will see like a cir­cle in the mid­dle of the cam­era when you are look­ing through it. ‚In the cen­ter of that cir­cle, there will be smaller cir­cle or a smaller square.‚ If you have spot meter­ing avail­able on the cam­era, it will mea­sure exactly what is in that teeny spot.‚ It is really handy when you are more advanced and you want your expo­sure to be based on a par­tic­u­lar area of the shot, but for most peo­ple the type of meter­ing that is non-spot that eval­u­ates the whole scene or the whole frame of what you are shoot­ing gives really good results.
A great tool that can help with expo­sure, espe­cially if you are just learn­ing or you want to per­fect your meter­ing tech­nique or you want to assure your­self of good results, is a gray card.‚ What the gray card does is the gray card is the exact mea­sure­ment that the cam­era is try­ing to achieve.‚ The cam­era is try­ing to make all the tones mid­dle gray.‚ Although this may sound weird for color pho­tog­ra­phy, again, it is try­ing to achieve a mid­dle color so that the expo­sure will always be aver­age and thereby cor­rect.‚ You can buy this gray card at any photo store and it is a great, great handy tool when you are learn­ing.‚ If you do come across a sit­u­a­tion where you are just not quite sure of expo­sure, espe­cially if you are with a non-digital cam­era and you can­not see result right away, what you could do is, let us say you are tak­ing a pic­ture an object or a per­son, well, you have that per­son hold the gray card or you use some type of device to hold the gray card in place and you approach the sub­ject and you take the meter read­ing off the gray card.‚ You approach the gray card and you have the gray card fill the frame of the cam­era.‚ You note the expo­sure on the cam­era and you plug that expo­sure in when you back up.‚ That will give you a very accu­rate result.‚ You should also be aware that the actual expo­sure is depen­dent on three vari­ables, which is the film speed, the aper­ture, and the shut­ter speed.‚ These three vari­ables, they change.‚ They are not con­stant.‚ Although you may use cer­tain a film or your cam­era may tell you that it is using a cer­tain film sen­si­tiv­ity, it is not always bang on.‚ As you approach in expe­ri­ence or as you approach bet­ter pho­to­graphic tech­nique, you may want to make smaller adjust­ments in order to achieve bet­ter results.‚ In using the gray card, you could really find out the dif­fer­ence between the camera’s expo­sure and what the actual neu­tral expo­sure really is.‚ I rec­om­mend using the gray card when you get like a new cam­era or a new lens or you want to really per­fect your expo­sure.‚ Just take a shot, put the gray card in the scene, approach the gray card, take the meter read­ing from the gray card and your cam­era, then keep that meter read­ing back up and take the shot as you nor­mally would.‚ A good thing to do as always would be to take the shot accord­ing to what the cam­era read­ing was giv­ing you from your posi­tion as opposed to what it gave you when you approach the gray card in the scene.‚ Again, it is a great, great learn­ing tool and expe­ri­ence.‚ The meter­ing we just talked about, this reflec­tive meter, it comes with the cam­era and it is great tool to use.‚ You can also have an exter­nal spot meter if your cam­era does not have one.‚ They are pretty expen­sive, but they are great tools to have as well.‚ What it does is to kind of looks a lit­tle bit like a gun, let us say, and from your posi­tion you aim it at the sub­ject and you can get an expo­sure read­ing that is very, very pre­cise from a small area on an exter­nal reflec­tive spot meter.‚ Very use­ful device for those that are more advanced who really want to per­fect their expo­sure.
Another type of meter that is very use­ful to have and most pros have one, or even advanced ama­teurs they have one, is called an inci­dent meter.‚ What the inci­dent meter does is it mea­sures the amount of light falling on the sub­ject.‚ It does not have to do with the reflec­tion back to your cam­era.‚ It is the actual amount of light that is falling on your sub­ject.‚ You approach the sub­ject phys­i­cally.‚ It does not mat­ter if it is a per­son or an object, but it is def­i­nitely some­thing that you can approach.‚ You would not use it for a moun­tain or a land­scape.‚ I guess you are good — if you want to get a lot of exer­cise, approach the moun­tain and then go back to your posi­tion and shoot, but it is really for por­trai­ture or still objects.‚ The ambi­ent meter or the inci­dent meter will mea­sure the light falling on the sub­ject.‚ The results you get from this meter are very accu­rate because it actu­ally mea­sures the amount of light falling on the sub­ject.‚ You can get into tricky sit­u­a­tions with the inci­dent light meter as well if dif­fer­ent mixed lights is falling on your sub­ject, but in gen­eral just play with it a lit­tle bit.‚ Again, check out the results either on screen on a dig­i­tal cam­era or when you get your film back and you will see that it is just an absolutely fan­tas­tic, fan­tas­tic device.
Usu­ally, when we use the inci­dent meter, espe­cially in tra­di­tional pho­tog­ra­phy, we are going to mea­sure for the shad­ows.‚ We are going to expose for the shad­ows.‚ If there is a mixed light within the scene, we are going to try and posi­tion the inci­dent meter and we are going to point it at the light source or toward the light source, but in the darker area of the scene if that makes any sense at all.‚ If there is like a bright ray of light shin­ing on the sub­ject at his chest level, you may want to mea­sure the scene below the chest level so that it does not totally blow out the scene.‚ You want to expose for the shad­ows in gen­eral and develop for the high­lights if we are talk­ing tra­di­tional pho­tog­ra­phy.‚ If we are talk­ing dig­i­tal pho­tog­ra­phy, just inci­dent record the scene.‚ Take the metered mea­sure­ment, plug it into your cam­era, shoot, and see what you get.‚ See what you are doing right or wrong.‚ That is really the beau­ti­ful aspect of the dig­i­tal cam­era; you can see the results right away.‚ Again, for any­one that is seri­ously into pho­tog­ra­phy, I highly rec­om­mend get­ting an inci­dent light meter.‚ It is so prac­ti­cal and such a great learn­ing tool and such a great use­ful tool, espe­cially if you are being paid to shoot.‚ Now, again, these inci­dent meters are a cou­ple of hun­dred dol­lars.‚ They are between $200 and $300 to buy them new, but you can often find them used on eBay or you can look in your local paper or go to a local photo store and you will find these meters used as well.
The only other thing I really wanted to men­tion about expo­sure is the dif­fer­ence basi­cally between tra­di­tional cam­eras and dig­i­tal cam­eras.‚ Although the tech­nique of mea­sur­ing the scene will be the same, again, you are going to want to make some small adjust­ments with regard to the meter read­ings that you are get­ting espe­cially if you see that your results are con­sis­tently off.‚ Film man­u­fac­tur­ers and the camera’s speeds, you need to adjust them.‚ They are going to be really good for most appli­ca­tions, but you are going to find that occa­sion­ally the meter read­ing is off and you are going to won­der why.‚ It is because they are not all bang on, you need to adjust them slightly by increas­ing the expo­sure either through expo­sure com­pen­sa­tion in the cam­era or expo­sure com­pen­sa­tion in the meter.‚ You really need to adjust the indi­vid­ual meters if you want to get the best result.‚ You also need to know that when you are doing your tests that although your eye can see the dif­fer­ence in lat­i­tude between the dark­est parts of the scene and the light­est parts of the scene, the cam­era can­not.‚ If there is a really huge dif­fer­ence, the cam­era will not be able to record it prop­erly regard­less of how you are meter­ing it.‚ Now, that is a whole other topic and we can go on and on and on about the fine points of expo­sure, but you need to be aware that if the scene is too bright, your cam­era will not be able to record it regard­less of the meter read­ing that you put in.‚ These types of sit­u­a­tions really only occur with expe­ri­ence.‚ After you have shot many, many pho­tographs, you will be able to real­ize, “Oh my good­ness, this scene is just way too bright.‚ I either can’t shoot this scene and record both sides of the spec­trum, the dark tones and the light tones cor­rectly, or I have to reduce the con­trast of the scene some­how.”‚ Some­times that always will not be pos­si­ble.‚ You need to give it up unless you have such a bud­get whereby you are able to really con­trol the scene with all kinds of equip­ment, then if the scene is too strange in terms of its bright­ness vari­ety, you just have to wait for another time or real­ize it is just not going to work or live with the results you get.
That basi­cally cov­ers our show for today.‚ As always, we appre­ci­ate com­ments in the blog and we also appre­ci­ate com­ments in the forum.‚ We are chang­ing around the blog a lit­tle bit.‚ I hope you like the changes.‚ You can sub­scribe, as always, for free in iTunes.‚ Just do a search for pho­tog­ra­phy pod­cast or Photography.ca Pod­cast and you will find our pod­cast.‚ We are going to have some direct links put up in the blog so that if you just click those links you will be sub­scribed in iTunes, which is a great pod­catch­ing soft­ware to have, so I rec­om­mend you down­load it if you do not already have it down­loaded, but a lot of you prob­a­bly do have it down­loaded.‚ That is it for the today.‚ Thanks so much.‚ We are going to do another pod­cast really quickly.‚ Once every two weeks I am find­ing is bit long, so I intend to actu­ally shorten that period in the very near future, maybe once every 10 days or even once a week.‚ Hope you keep on lis­ten­ing.‚ If you have any ques­tions, shoot them my way.‚ It is my plea­sure to answer them, either via email, via the blog, post­ing in the forum.‚ Always my plea­sure, love talk­ing to new­bies, love talk­ing to pro­fes­sion­als through email or directly.‚ Again, thanks every­one for lis­ten­ing.‚ Have a great day and keep on shoot­ing.‚ Bye for now.
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