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Exposure Values and Apertures

next up we want to talk about exposure values what do we mean by that well that's all the numbers you know values so we're going to talk about the sl where do we want to have our s o at and where would we and when would we adjust it at different settings so obviously lower is better I'm sure all of you learned that a long time ago and so if you want the optimum quality you want the lowest native so your camera has on most of our cameras these days that's s a one hundred I know on some cameras that is a two hundred rating and on some other cameras it's sixty four and so it it varies in there but one hundred is the most common were going to jump it up if we need higher sensitivity and the guidelines are pretty simple you want to keep the so as low as possible and the only real reason that you're going to want to adjust your s o is for the sole reason of faster shutter speeds if you need a faster shutter speed that's the reason that you're going to go toe a higher I sl and that's the only...

reason that you should be changing your eyes those if you need a faster shutter speed so let's just kind of take a quick look through a bunch of images and different isos that I've used to shoot them with now the lowest standard esso I have in my camera is one hundred but I do have an extra low setting that I could go to down to fifty if I really want to and the reason I wanted to go down to fifty is that I run into a really long stutter speed and so in this case I'm trying to have this lois shutter speed as possible so I'm trying to make my sensor as a little sensitive to light as possible and so I'm able to get down to a longer shutter speed in this case another case of trying to slow those shutter speeds down with water movement using s o fifty now the reason I don't use sl fifty though all the time is because the native sensitivity the standard sensitivity of my camera is I s a one hundred when I go down to fifty I am giving up a little bit of dynamic range and so I would never want to use fifty in a high dynamic range environment and these images were not what I would call a high dynamic range we didn't see sky and land or son and land at the same time and so you do give up a little bit if you go to one of those low setting so generally the place you want to be for most of your work is the lowest numbered setting that your camera has not the low setting one hundred for most of us and so this is where I'm going to shoot most of my landscape work whether it's bright out or dark out it doesn't matter I want to shoot at one hundred because that's where there is the cleanest information and so if I make an enlargement there's going to be as little noise as possible on my camera why am I going upto s o two hundred to shoot the shot because I'm on a ship that's got a lot of vibrations I'm out on the water and I am concerned a little bit about my shutter speed because I have a telephoto lens and all these other factors which might cause blur because I'm not able to use a tripod in this situation in this case I'm up in an airplane and I'm conscious of my shutter speed and I needed it reasonably fast shutter speed so that I could stop the motion of the vibrations of the plane I s o four hundred I'm hand holding this shot because I wasn't able to position my tripod in here because well frankly some people would have got very mad if I started putting tripods into their flowers and so I was essentially hand holding this camera with a fish islands in this case I would have a thirty second exposure and so it was really a cz long as my camera would go without getting on to a long time or with the cable release and I didn't want to go any longer than this and I was willing to sacrifice a little bit from one hundred to four hundred one of the other problems here is that the longer I left my camera in the sand it would slowly sink after a period of time and so I had to use a little bit of a faster shutter speed I didn't want to leave it there for twenty minutes obviously concerned about more action here I'm thinking about a shutter speed shutter speed in this case is won three twentieth of a second but I'm letting the maximum on alight in through my aperture I'm getting that a little bit faster shutter speed because I bumped up that s oto higher number in this case I bumped it up to s o because I was at the max of my thirty seconds on my camera I would have had to go into a longtime remote if I wanted to get down to one hundred and my camera's still maintains a very high quality at eight hundred so I don't have a big problem shooting eight hundred on my camera I prefer to be lower but eight hundred is still very good it's very rare that I go beyond it for landscape photography down in antarctica shooting some of the icebergs on a very very rough ocean the boat is moving around quite a bit I'm shooting at a four hundredth of a second to stop the motion for doing star shots at nighttime you're going to have to bump up the so here because there's movement of the stars I'm using a fifteen second exposure eso thirty two hundred and in a very rare case I was trying to stop the snow falling so freezing the snowflakes in the air requires a pretty fast shutter speed which required me to go up to fairly high is so that I would not ever use normally is very unusual for me to use this in a landscape shop but there's a lot of movement that I was trying to freeze in this particular case and so like my lenses I've gone in to my light room settings and I wanted to see what ias ozai use and how often I use them so what do you think this graph is going to look like heavily weighted seventy percent of the time I'm at I s a one hundred when I'm shooting landscape type shots and less than one percent of the time my ever over eight hundred and so years is going to look a little different in mind it all depends on what you shoot but it should be heavily biased to the lowest setting in your camera next up is the shutter speed where should we set our shutter speeds what are we concerned about lonely set them so the reasons for adjusting your shutter speed to start with technical we want to let in more light we want to let in less light faster and slower shutter speeds but it's also the aesthetics do we want to freeze motion do we want a blur motion is there any motion that's moving good questions to ask looking at the shutter speeds the common shutter speeds that I find myself at this somewhere between the sixtieth of a second and thirty seconds if I'm trying to do that blurry water movement that's typically going to be around a full second in that general region and just in case you're curious if you are shooting wildlife it's going to be generally in the faster than one twenty fifth setting so often around five hundred thousandth of a second so let's take a quick cruise through some of the shutter speeds and look at how they affect the image so one of the big ones that we shoot a lot of moving images of is water rivers and so forth and so on two thousandth of a second we're freezing the motion and as we get to slower and slower shutter speeds at a certain point we hit kind of a a break point where when we look at this image and this image here we've just started to get some blur everything faster than this has frozen the action pretty well and then we get to some kind of in between awkward areas where we're getting a bit of motion but not a time and around fifteenth of a second we're starting to get pretty good motion and this is where it starts looking really good in my opinion where if you want to get these long flowing streaks you're going to get them until we get all the way down a one second and so the difference between one second fifteen seconds to fifty thousand could be very different and to kind of hammer this point home this is a great little home test for you to do a little activity go find a local river waterfall and run your own shutter speed test on it doing this yourself really hammers home the point about what the shutter speeds will d'oh and you're going to find an area that you kind of like things and you may or may not like what I think is good but you're going to find your own areas your own shutter speeds that work for you and the type of work that you do you'll notice in this shot at a quarter of a second that we've got kind of a mix of sharpness and blurriness because water is moving at different speeds here on the ocean's edge moving down to a half second waiting for a wave to crash on top of iraq and this is where I wouldn't be using my two second self timer I'd be using my cable release so I could really time something as it's exactly happening a full second is very common when doing your standard landscape type shots you're down here in a very slow shutter speed because you have very small opening in your apertures which we'll talk about next as the light level gets a little bit lower you'll be down in two seconds death valley at the racetrack in the evening you go into a forest in the middle of the day you could be at four seconds there's not a lot of like getting in there so is the light levels or get lower getting lower as you're getting more depth of field and you're closing your aperture down and as you're leaving your s o one hundred for most all of these shots you simply adjust by changing your shutter speeds and if there is nothing moving in your shot your subject you're subject to stationary and your camera is nice and steady on the tripod it doesn't really matter what cheddar speed it isthe you can use as long of shutter speed as you want I'll often be using long shutter speeds like fifteen and thirty seconds when I'm doing night photography this is kind of unusual that if you're wondering what that very light bright light is in the background that is a fishing vessel I believe is using lights to attract fishes and then thirty seconds for my nighttime photography so what sort of shutter speeds do I use for my landscape work well a wide variety I would say depends on exactly what type of look I'm working with so this one is not nearly a center so I can't really tell you what's the best shutter speed for shooting a picture our rock well I guess that's any shutter speed it's just really is that subject moving is the concern and that's not something that we shoot a lot of in landscape photography it's a portion of the work but something I want you to notice about this graph notice where this handheld line is this is this is kind of my limit of handholding just below a sixteenth of a second and about seventy percent of the pictures that I take I need to be on a tripod to take when it comes to landscape work and so if you're wondering well how much of the time do I really need a tripod it depends a little bit on how you shoot but for me I need a tripod seventy percent of the time for doing landscape in nature shots all right let's do aperture so aperture is one of the more important settings they're all important but this one is something that is really important to the landscape photographer because depth of field is a critical issue obviously we're going to be changing aperture to control the amount of light for technical reasons more light or less light but we're going to be controlling it for the reasons we've been talking about having more depth of field let's step the field or that maximum sharpness which is in the middle of the rage so let's look at how I would set pictures at different apertures I don't normally shoot pictures at an aperture of one point four but if I am doing star point shots I need to let in a lot of light through the lens because it's very dark and I can't use too long a shutter speeds otherwise the stars will show in their movement from the earth's rotation and so I'm going to be using a one point four two point oh or maybe even a two point eight aperture one point for this is that this is kind of a rare shot for me but I am shooting intentionally very shallow depth of field I wanted that look of a couple of flowers and focus but very little else where in focus moving up to two point oh going right back to the nighttime photography to point it was probably the most common aperture I will use for doing the star shots or nighttime landscape shots for the flower shots it's kind of fun to do the shallow depth of field where you have one and focus and a whole bunch of them behind it out of focus any time you want to separate a subject from the background you focus on that subject and you have that background a little bit blurry it's a good way to identify what your subject is versus a secondary subject why am I shooting two point eight on this well what you don't know is that I'm on a boat that's moving and I'm shooting a very flat surface this is a glacier carved wall up in alaska and I just thought it had kind of a neat texture to it and the boats kind of motoring passed and I need to keep a fast enough shutter speed and I really don't need more than two point oven eight aperture toe hold it and focus because it's a very flat subject going to four point out a lot of my lenses I shoot with like my seventy two hundred the maximum akrotiri is four point this is the shallow depth of field I can get on kind of one of my standard lenses that I always have with me in this case I'm trying to separate the tree from the background so isolating subjects using shallow depth of field shooting at five point six on this one because I'm shooting from a bridge straight down it's just kind of an abstract shot but I'm shooting just flat down on the ground and I don't need depth of field and I'm handholding the shot because because I can't get my tripod in position on the outside of the bridge and so here in the middle range of the apertures I'm shooting objects that don't have a ton of depth to them the sand dune is a long ways away and the nearest to the furthest point really isn't that big a deal and so I can do that with just a five point six aperture these trees don't very in distance from me they're all about the same distance from me so I don't need a great depth of field and this is where I'm really shooting my lens at its very best f ate is just a great place to be for true sharpness on your lands it's not the most f the field but it is the greatest sharpness on many lenses and so I'm shooting a relatively flat subject in this case once again shooting from a ship as I get into f eleven I'm starting to need more depth of field and so I'm having subjects that are closer to me as well a subjects that are a little bit further away and I tend to kind of by default started f ate and then work my way either up or down from there depending on how close the subjects are to me how much depth is in the photograph how much depth of field is necessary for that particular situation when I get down to f sixteen I've gotten pretty serious I need depth of field I got subjects that are close to me subjects that are much further behind it and in this particular case I'm also using a telephoto lens which inherently has less depth of field and I'm trying to compensate with that compensate by setting f sixteen to give me more depth of field when I get to have twenty two it's basically pulling out all the stops trying to get as much in focus as possible because there's something likely very near the camera that I want to have in focus in this case literally inches away from the camera so when it comes to my landscape apertures what do you think I'm going to be choosing most of the time well very rarely do I even have a one point four a two point oh or a two point eight lens with me I do have those lenses but I don't normally take him out in the field they're kind of special purpose things most of the time I'm going to be at f sixteen I'm not you know you have twenty two because that's where you get some more noticeable diffraction yes you do get diffraction and f sixteen it's not that big a deal it can be corrected with a little bit of sharpening and so there is a little bit of variables to play with in there but that's where I'm setting my camera for most of my landscape stuff okay so how would I actually go about this in the field one of my thought process is one of my doing all right so I'm in death valley down at badwater I got foreground really close in front of me that I want to focus but I also want the mountains in the distant to also be in focus this is one of the standard things that you're doing in landscape photography I s a one hundred because that's where my camera is at its best and its probably where a lot of your cameras is at its best sensitivity get the cleanest information off the sensor what's important here is our depth of field we want to maximize the depth of field now normally I don't like to go to have twenty two but this is an extreme case we have a subject extremely close to the front of the lens so we need f twenty two and I know there's some people out there they're kind of sharpness geeks they're like I never set f twenty two because my lenses not a sharp well if you need it you go for it and you do it so I'm going to set up twenty two and you know what shutter speed I said I don't care it's whatever makes the light meter happy if the light meter says you need more light in I'm just going to keep changing that shutter speed until the light meter evens out and that's where I'm going to take my first shot I might take second and third shots adjusting the light meter accordingly but this isn't a case where I need maximum depth of field and this is where I'm photographing something that's writing close in front of me and something that's further away and that's a very common thing in landscape photography the other type that's very common is we're shooting a detail that's kind of flat that's not stretching out towards you in away from you and so some trees at yellowstone what's going to be my settings here well of course I'm going to be at ice a one hundred that's my preferred now in this case I don't need maximum depth of field I want maximum sharpness which is going to be towards the middle of my range could be f eight eleven something in that range what is my shutter speed well I don't really care wherever it is it is if it was one hundred twenty fifth of a second I could hand hold the shot pretty easily but it isn't because my light meter says I am will more than two stops underexposed indicated by that little red era so I adjust my shutter speeds until I even out my exposure quarter second okay fine let's take the picture and so that's right took this picture now for those of you who are still kind of hung up on that tripod thing that we talked about a little while ago you know like I really don't like to carry a tripod what what changes what I have to make if I don't want a drink try because I really don't want to bring a tripod okay well let's figure it out let's not bring a tripod in this situation what do we need to change well let's remember where we were at and now let's change r shutter speed to get to something that we can hand hold like one hundred twenty fifth of a second how many stops of light did we just lose count him up look at the shutter speeds you go down to four and just counted up one two three four five we just lost five stops like we've got to get that back and how are we going to do it we're gonna have to make some changes we're gonna have to let in two stops the light with our lens we got an extra two stops there we're not going to get that extra sharpness that we get it f ate got to give that up handheld the only thing left to do is come overto esso and make up for the next three which brings us upto so eight hundred eight hundred's not the worst in the world but also eight hundred it is not I also one hundred so you've compromised your pictures because you didn't bring a tripod which is your call as to whether that is worth it or not I don't want to be someone that says you have to bring a tripod but just realize what you are giving up by not taking the tripod there is a compromise to be made and I think that brings us to the end of our exposure section a lot of stuff come up and join ya you just powered through that one I really really appreciate those graphs where you show us exactly what you're shooting the most are what you know where I am where the settings are yeah what with the appetite of the most and what have you because shutter speeds the most for this type of photography was really really happening for me and that's one of the things that's kind of nice about light room we'll give them a little plug but also keyword in your images I keyword my image is of a type of images so I have like sports have wildlife part trick nature and landscapes so I could tell you what that is reported or any other genre which is kind of funny super cool okay a couple of questions because we don't have much time from sam cox got several votes on it you know that's not the ones well okay maybe have you graft what time of day you shoot to get your I was one of those two stars and better images I haven't figured out I haven't figured out what time of day that I shoot things the most alright it wouldn't really matter because I've been in so many locations that have sun sunrise at either for a m or seven a m and so you kind of want to notice I would like to know plus or minus sunrise on that day where were my best shots and it might be like they're always twelve minutes after sunrise right right right of okay this is from henry to in the film days you approached diminishing returns with longer exposures does that happen with digital sensors I think what they may be referring to not diminishing returns but failure reciprocity failure is when film no longer accumulates light in the same way so the difference from thirty seconds to a minute is different than one minute two minutes even though you've doubled the time you've doubled again it doesn't it has a color shift and when it comes to longer exposures rarely on ly rarely will I shoot longer than thirty seconds because the sensors heat up and you get start getting long exposure in no ways and so most of the time I found that you don't need to go longer than thirty seconds I've gone I think the longest shutter speed I have is about five minutes okay great uh last one can you explain again why the greatest depth of field is not the maximum sharpness so the greatest step the field has a little bit of a problem and I may not even know the scientific technical answer but it's basically when you stop your aperture down to a very small opening as the light squeezes through that very small hole it gets diffraction did and it doesn't get focused on the sensor exactly as it should and it ends up being a little bit soft and not not a sharp do a test yourself it is basically because we're squeezing light through a very small opening and I know some people as I said before they'd never shooted f twenty two well if you don't have to congratulations but for those of us who have to I have no problems sending it to have twenty two or thirty to one of the secrets about this is that if you are getting some diffraction you khun kind of counter balance it with post process sharpening so you can you sharpen in photo shop for light member many other programs and it will balance things off and I have never shot a picture at f twenty two that I am embarrassed to show because I feel like there was too much diffraction I would prefer there to be less but it's not enough to really cause a problem