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Sensor Size

Lesson 5 from: How to Choose Your First DSLR Camera

John Greengo

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Lesson Info

5. Sensor Size

Next Lesson: Pixels

Lesson Info

Sensor Size

We used to deal with different film sizes and cameras and we have many different sensor sizes so let's talk about how this impacts the type of camera we're gonna have so with an slr you take the lens off, you pop the mirror up, you look behind the shutter and that is the censor. This is the device that is gathering light and creating the pictures in our camera and the size of it is very important in order to determine the quality of pictures that we're going to get what type of lenses were going to use and how big the entire camera system is now there are lots and lots of different camera sizes out there. This is these are just a few of the more popular choices out there to explain the sizes it's easiest to start with the largest of these which is based off of thirty five millimeter film thirty five millimeter film has nothing perfect about it. The only thing that is notable about it is that it was super popular for about fifty years and it was really the way photographers talked about...

in reference to lenses and camera types that that was the standard that people have. We had cameras smaller and we had cameras that were larger in their sensor and image areas but that was just the most popular one and that's the only reason why it is where it isthe is just popular so we have sensors in some cameras that are full frame sensors. The exact same size is that thirty five millimeter film, but because sensors are expensive to make that are large, many manufacturers make smaller ones also because they can put them in much smaller, more affordable cameras. And so we have a variety of sensor sizes, and whenever I look at this list and when ivory teach classes about sensor sizes, I always get frustrated and mad at the photography world because nobody runs the photography world there's a whole bunch of manufacturers. I have a lot of input, but nobody is looking at things going. This doesn't make sense, and if you look at the names the words, the acronyms, the letters and the numbers, how is it possible for somebody who is new to photography to compare one sensor size to the next? And I think I have a solution to the problem, and that is let's. Just measure it the same way we measure our computers in our tv screens from corner to corner, and so a full frame sensor is forty three millimeters from corner to corner. The next one down is twenty eight, twenty seven, twenty two and onward, and so now you can compare these sizes, and I'll warn anybody who is looking at sensor sizes for the first time. This is simply a john gringo thing. I the only one that's doing this right now, nobody else is doing this. Maybe I'll get it instituted into the industry. I think it's a much better system for talking about sensor size because it's much easier to compare, ask anyone what's the difference between twenty seven and forty three, and most people are going to figure out a way to make a difference in that ask him the difference between full frame and a psc, and that doesn't make a lot of sense, but that's the terminology that is often used in the photographic industry, the cameras that we're going to talk about in today's talk are these larger sizes from four thirds up to the full frame full frame, of course, is the same size is thirty five millimeter, and this has what we call a crop factor of one point. Oh, it just means it's the same size is thirty five millimeter film there's, a number of manufacturers that make cameras in this way. Pentax currently does not have a camera there, but they have plans to have won their very soon smaller cameras. Nikon, sony, pentax food, you there's a lot of them that use this one point five crop factor, which means it's smaller by a factor of one point five where did that one point five come from well, you remember our forty three and twenty eight. If you run a little bit of math with those numbers, you'll find out that you need to multiply one twenty eight by one point five in order to get up to forty three. And so it's, smaller by a factor of one point. Five cannon is kind of unusual doing there. One point. Six it's, very close to the one point five will often just group those together. The four third system is going to be using a much smaller sensor on it. They wanted to do this so that they could have cameras that were significantly smaller in size. And so, just as a quick reference, we'll do some more size references. Up here. Here is kind of a full size professional camera here. Let's where's. Our a p s will do a pentax k three here, and so you can see the size difference here between a full frame camera and an a p s c sensor, which is a twenty eight millimeter sensor. And if we want to go a size smaller, we can pull him that guy there, which is the four thirds camera. Now we do have a much smaller lens on it, but you can see how these micro four thirds cameras can be much smaller in size compared to the much larger sl ours and so choosing the right size sensor is going to get into the right size camera and that's one of the first most important choices to make. So what is the impact of using a different size sensor? Well, let's take a look at an example let's say for the moment that we're using a full frame forty three millimeter sensor in order to take a picture so we're using that entire area to capture our image now let's use the same lands same camera position but use a different camera with a smaller size censor what is a smaller sensor look like? Well, let's use a twenty seven millimeter sensor and you can see that this picture is slightly different than the first one because well, we've done is we've cropped in to use that smaller area now this larger image was taken with white angle lands sixteen millimeters and if we wanted to get that exact same picture with a smaller size sensor, we're going to need a different lens because it's a smaller size sensor in the lens that we would need would be a ten millimeter lands and I hate to introduce math at this point in time but there is a bit of math involved in photography how did we figure out it was a ten millimeter lens when we knew we started with the sixteen and we were going to a one I think six crop sensor, which means we've got us down to ten millimeters, and so there's kind of these equivalence. If you're using this size sensor, you need this size lens equal what this other one dead and so ten millimeters weaken, multiply it by the crop factor and go the other direction, which is a little bit easier to figure out what the full frame equivalent is of that lens. And so we often talk about different size lenses, depending on the sensor size. Now we can also do this with telephoto subjects. And so here, let's, go up to alaska, take picture of a whale jumping out of the water, and if we were taking this picture with a cropped frame camera, it's going to be concentrated more on just the middle of the frame? And so we're not getting as much angle of view from side to side. And so, in this case, it's actually a little bit of a benefit because we have all of our pixels mohr on our subject that we're concentrating on if you wanted to get a picture like that, I would recommend a three hundred millimeter lance think this would be a good lens it's, kind of achievable in the price range in size for for the enthusiast photographer and if you're thinking well, you know if I had a full frame camera it would be a better picture because full frame sensors are better in quality what would it take for me to get that with a full frame sensor? Well you're going to need a different lens you're going to need a more powerful lens because you have a bigger sensor and we've got to run through a little bit of math again sorry folks three hundred times our crop factor one point six puts us up at four hundred eighty millimeters and lucky for you they make five hundred millimeter lenses now the downside is it twice the length hits three times the weight and seven times the price and so if you do want to get the ultimate an image quality, there is a price that you were going to have to pay for that and this is true whether you're talking about a five hundred millimeter lands or almost any other lens as we go through the gamut, I'm going to give you a bunch of price comparisons because the full frame is going to cost you the most of these the larger it is the more it's going to cost you so when it comes to the sensor size which is ultimately going to determine the size of bag that you carry your cameras around in here's some thoughts on the bigger sensors versus the smaller I'm not talking about any particular size but just in general bigger versus smaller, bigger sensors have bigger pixels, which are better at gathering small amounts of life. We're going to talk more about this in the next section on pixels, but that's just kind of a well foreshadowing of what we are going to talk about. A bigger sensor has room to put more pixels on, so you're going to find that they typically have higher resolutions as well. Overall image quality is going to be better because of the two above factors on it they're going to have very good ability in low light, so if you're working a lot in low light you want to get a bigger size sensor. It is also going to give you the option of shooting shallow depth of field, so if you do portrait photography, portrait photographers love throwing the background out of focus because that way your eyes go right to your subject in the photograph and I'll have some examples for that coming up in just a moment smaller size sensors mean you get a smaller size camera and it means the lenses are smaller in size and it's less weight and all of that means less materials, which means it's probably going to cost less money and so it's a hard tradeoff I gotta admit on I know a lot of photographers that I haven't been able to make a decision, so they have multiple cameras that fit different types of needs, so I thought I'd be nice just to do a quick comparison between three different popular size cameras and we're going to choose the nikon seven fifty as our full frame slr the food g x t one is our one point six crop factor actually one point five prop factor on that camera and olympus, which is our micro four thirds camera and you can see the weight of the cameras down there with a body and a basic lengths now that will be thrown and change depending on what lens you have on there. And so this is not a one hundred percent fair comparison because these air different cameras with different types of lenses, but these might be a common system that you would have now. All of these sizes are very, very close to being relatively correct, and so you can see that there's a fairly large size difference in the camera. Now the bigger cameras, as I mentioned before, have bigger buttons that are easier to press, the smaller the buttons, the closer they're clustered together, the harder they are going to be to identify impress real quickly when you're shooting in a low light situation, for instance. Now the cost of the camera just the body only not the lenses we're going to look at a relatively small difference between the four thirds and that next one point five crop factor so you don't save a lot of money by going to the fourth third sensor but you do save a lot of weight and size and then when you go up to full frame it will be noticeably more money and more size aa lot of people have a big dilemma in trying to choose between a full frame sensor and the crop frame sensor and so let's just take a closer look at this comparison right between these two so full frame versus a ps first off a ps is a term that has hung around since the mid nineties. This is a photo system that was used for about five to ten years and it had to do with the size of film that was used in these slightly smaller cameras that as I say we're out for a short period of time so our full frame sensor as I mentioned before is twenty four by thirty six or forty three millimeters across the a p s it is going to be twenty four by sixteen that's where we get the twenty eight some of you who like to compare areas the larger one is two hundred twenty five percent the size of the smaller one the smaller one is only a forty four percent of the larger area and so there is a significant size difference when it comes to actual area between these two sensors, which is why there's a big difference in the size of lenses and the prices of everything? And so I like to just pull out almost random example. So for instance, let's say, you shoot with cannon, and you need a lens that gives you a seven degree angle of you, and by the way, this would make a really nice sports photography lands, and you need an aperture that opens up to f two point eight, which is a really nice aperture toe have if you're going to shoot sports with your outside or inside, this is what a lot of professionals would want to have if they're going to go photograph a basketball game. If they decided I want to use a full frame camera, what would they likely choose or have it's an option? Well, five d mark three would be a good choice. They could go a little bit less on the camera, but this is this is a good choice for the lens. This is their only choice. There is no other cheaper lands that's going to get them that angle of you at that aperture from cannon, so they're going to spend about ten thousand dollars if you said, well, you know, I could probably do this with a smaller crop frame camera what would I will use? Well, you could use the cannon seventy mark too, which is very comparable and features but has a smaller sensor. You only need a two hundred two point eight, and there is a huge difference between a two hundred two point eight and a three hundred two point eight lands and you can get into the whole system for less than one third the price. And so for a sports photographer, it is much, much cheaper to get in on a crop frame sensor, then a full friend who's going to get better pictures? Well, if they're equally talented photographers, I would bet on the full frame that three hundred two point eight better quality lands cameras going to get you a little bit better. Image quality let's take a completely different scenario, let's say you want to get a nikon system and you're not sure between the nikon d seven fifty it's, a new, very popular full frame camera in the brand new theseventy two hundred, which is a very good camera in its own right? Well, whenever I sold somebody a camera, I would like to get them appropriate lenses, so if they buy a bottom of the line camera, I didn't typically go show them the most expensive top of the line lenses, because if they had that sort of money, they probably would have upgraded the camera body, and if they buy a top of the line camera, I don't show them the bottom of the line lenses. I remember several years ago when a new camera came out and it was it was a step ahead of everything at the time in that price range, and there was a lot of people that got really excited and they went out and they bought the camera because it was just within reach of their budget, but because they spent so much money on the camera body, they didn't have enough money for the lenses, and that camera had a very high return rate and it's not because there was anything wrong with the camera it's, because they did not buy appropriate lenses. I mean, the the audio analogy is, I don't know what sort of device is people are buying now because they're using their ipod so much, but you know, it used to be if you bought a good record player, you had to get good speakers. If you want to get that sound as if you got cheap speakers, it doesn't matter how good your record player is, that sound is not going to transmit, and the same thing is true with cameras, and so what I would recommend for somebody buying a seventy, two hundred is going to be different than the d seven fifty. So seventy, two hundred a nice to lens outfit that I think is appropriate would be the sixteen, eighty five and seventy two, three hundred package price around twenty, three hundred bucks, and he said, well, you know what, the d seven fifty what is that that's like an extra thousand dollars? Well, the whole package just be a thousand dollars more? Well, no, because you're probably going to want to upgrade the lenses to match the quality of the body, and you're going to end up spending more than twice as much money. And so a lot of people don't anticipate these extra costs because they need to upgrade everything. They go along with the upgrade camera body, so do take a look at the complete final prices. All right, let's, do another test here. So what I decided is I wanted to do the pro zoom kit. So what the pro zoom kit is is that you talk to just your typical pro photographer. It is so common for them to have two basic lenses in their system and what they're going to have, they're going to have a twenty four to seventy two point eight lands in a seventy two, two hundred. Two point eight system now I know a lot of people buying their first dslr this is not the lens system that you're going to have this is more of an example of a fair comparison between three different camera systems so how much are you going to spend on a body and to really nice zoom lenses? Well with the full frame system you're looking at six grand u s dollars and it's going away about seven pounds now you go down a size I'm going to go down and I'm going to use the fuji sixty one is an example here one of the more popular high quality a psc systems on the market the fuji has their own equivalents to the twenty four, seventy, two hundred on lee in this case they're different lenses because it's a smaller size sensor so we have a sixteen to fifty five in a fifty to one forty and that's immediately going to take a third of the price down just because we're using equipment that's designed for the smaller size sensor as far as the angle of you and the light gathering ability these two systems air doing exactly the same thing and we have cut the price and the weight equally down by about one third in both those factors if we decide to go one step smaller the olympus o m d e m five mark two new camera that's out on the market now very small in size and so they have their own lenses that are equivalent an angle of view and light gathering ability because they all have two point eight aperture, and so the angle of you is going to be exactly the same. And so these air, very fair comparisons, and we're talking about close toe, half the price of the full frame cameras, and when it gets down to the wait, what is that about one third the weight? And so for somebody who was wanting to travel very lightweight, then I would direct them strongly to the four third system because it is just so much smaller and so much lighter it's not truly that much less money than the psc. And so for your average photographer, generally, I start with that middle size sensor, and then we go up and down from there, and so I just kind of think of this is small, medium and large now there's one issue that I know there's, some nerds, possibly some geeks out there that are just they're they're hopping up there, there there they're waiting for the forum where they can comment because I said that these lenses were equal lenses, they are equal in their angle of you, what you see from side to side is exactly the same as far as what aperture you would set in the camera to gather light in to expose your picture would be exactly the same where they're not the same is, well, this is a two hundred that's, a one forty and that's a one hundred and a one hundred one forty and a two hundred are just going to look different because they're different lenses and there is a difference is that you will be able to get shallower depth the field with these full frame cameras. So let me show you an example, so I'm going to be using all three cameras in this example, and so I know you want to look at our model are beautiful model here, but what I actually want you to do is to look at the building in the background and the foliage over on the right hand side of the frame. So this is shot with the four third sensor, and what we're going to do is we're going to look at the same picture taken with the other different sensors and so look at the building in the background, and you'll notice that as we use the larger size sensor, that building becomes more and more out of focus. Now, this is something that a lot of photographers, well, they obsess about how out of focus is our back. Grounds and it's something that if you probably just ask somebody walking down the street the difference between these pictures they would have a hard time seeing the difference but for those who really liked to get into the subtleties other picture will know I want that background really out of focus. Well, if that's what you want to do the larger size sensors will more easily be able to do that on different types of lenses. And so if you do portrait photography if you want to isolate your subject from the background larger sensors just do a better job of that but you have to really look at a fair looking how important is it? Because you can use the four third system and get that shallow depth of field look it's just not as shallow one final little note about sensors and you will see this referred to in the literature about the cameras that you buy is that you will occasionally see cameras that do not have an a filter and so in a filter is an anti alias scene it is also known as an optical low pass filter sometimes oh lpf is the terms they will use in there and part of the problem is is that on our sensor we have all these columns of little pixels that are recording the light and when we record something like the fine pattern of a shirt well let's bring out our moray example and so when you have two columns of rose and they're slightly misaligned, you're going to get these weird patterns and you've probably seen at some point in your time a newscaster who has a shirt or a tie on that doesn't match the sensor in the camera that's recording them and it looks like it's on fire and it's glimmering and you get this more a look so in order to avoid this more a problem, a lot of cameras used this anti ailey seen filter and what it does is it takes a beam of light and it splits it ever so slightly this is highly exaggerated in this example here and what it does is it's technically blurring your photograph a little bit and it does this so you don't have a marais problem. Well, now that we're starting to have some very high resolution sensors were getting less and less marais problems with an infinitely high number of mega pixels, we wouldn't need this filter we need it mohr with lower resolutions and so a number of cameras companies have decided to take this filter off the camera in order to increase the sharpness of the photographs you may end up with some marais problems on it and it's a careful balance now the difference among the the best nerds that we have out there testing cameras is that there is an extremely subtle difference between having it or not having it and so there's a number of camera companies that are using systems and so you kind of have to check with that particular system as to whether it has that filter or not it's not a make or break point but it is something to be aware about and this is all in the name of just educating what are the things you're going to see and what do they mean and how important is this? This in my opinion is very unimportant I own a few different cameras some of them most of them have the a filter on it and I get great chart pictures with him and a few of the cameras don't have him and I get great pictures from them and so it's in the end result I would tell a beginner just don't even worry about it but it is something that you will see you should know about and I want to be the first to tell you about it all right? So among our three different sizes are small, medium and large is I like to call them some thoughts about them so the largest sensor is of course going to give you the ultimate in image quality it is going to be the best in low light work if you want to be a professional wedding photographer working in dimly lit arenas you want the full frame sensor because this full frame sensor is based on the thirty five it's just a very large system of lenses, cameras, accessories out there. And so this is the most common way that pros are going to shoot that's the system, the top eyes, so that I think is good in most of these cameras is aiso sixty four hundred. We'll talk more about this sensitivity over ice a little bit later on when we get into the exposure feature. But generally speaking for most of those cameras, I also sixty four hundred is something that I would use in a bar. For instance, if there was a band playing on stage and I wanted to go photograph them, I would probably need to be a tie so sixty four hundred if they didn't have really good lighting there. So for most people, I think the middle size is the place to get started. I think the value for the features that you get are going to be really good, these air, actually some of the least expensive camera's that you could get because they're very, very common these days. I think this is going to work out quite well for people who are interested in sports and wildlife because all those lenses have a little bit more reached to him if you remember the example back a few minutes ago. Comparing the two hundred two point eight versus a three hundred two point eight it just makes that a lot more accessible for most people this is noticeably less money this is about one third less money is I ran through a number of the different costs among different types of comparisons than full frame cameras the top good aya so in most of these cameras is going to be a stop lower about thirty two hundred which is going to be pretty good say for your typical high school gymnasium if you were going to photograph ah graduation a band or a sporting event there the little four thirds cameras are obviously going to be the most compact cameras they're going to be the lightest weight of the cameras and I would estimate on many of these cameras that the top good idea so was sixteen hundred now the top good I s so this is my subjective judgment and you might some find somebody else who disagrees with that you might find a camera that is an anomaly that is either better or worse in that category and so let's just take a look at a few of the cameras over here and so you know these are little tiny small ones here we actually have a few of the micro four thirds of these come in different sizes according to what you might want and the full size slr is really don't look that much different then our crop frame sensors, a lot of that, his lens on there so you kind of have to draw that off, and so I find both of these to be very, very comfortable cameras to work with, to be honest with you, I like the micro four thirds cameras and actually just picked up this o m g m five mark two I'm gonna be doing a class on this, this one coming up so as I have some time to build that class, and I like the size of the camera, I like that little tiny bag dick that it can fit in, but to be honest with you, these buttons are just small and their new, and I'm still trying to get used to exactly where they are, but you know, when you're and I photographed a lot of sporting inaction events and it's, so nice to have that extra little space between the buttons so that you can reach and find those buttons really, really easily when I'm actually shooting. This is what I want to be shooting with when I'm walking from a to b I like carrying this with me, but when I'm there shooting, this is the ultimate item that I would prefer to be shooting with it's a little bit heavier, but it feels really good in the hand it's got a great view finder and so all of these cameras are going to be a bit of a compromise I have owned probably about fifty cameras in my lifetime, none of them have been perfect. Every one of them have been a compromise of some sort and it's, just something I work with it's like that apartment you rent when you're going to call it, you make it work it's not always perfect you just try to find something that fits your style and your needs the best you can. Yeah, we do have one question hannah wants to know I currently own cannon sixty d with three different lines is and use it for portrait and wedding photography. I'm just starting my work and not bringing in a whole bunch of money at are there advantages to a full frame sensor enough that I should upgrade for the sake of producing quality work? So I think the bigger question is like, at what point is it like if you really want improve your craft and improved and grow your business? Is there going to be a huge noticeable difference with the end result of a full frame sensor versus right? So the two main differences comes down to the top, so that ok, she can shoot out is probably around thirty two hundred if she upgrades, she could probably go to sixty four hundred, so if you're shooting outdoor weddings this is not important at all if you're shooting with reception halls that hardly have any light and your pictures are just really not cutting the mustard that's a technical solution to solve that problem. The other issue if you remember the portrait shot the girl in the red dress getting that extra shallow depth of field that in my opinion is probably not going to take you over the top into the professional world and suddenly your business expands because you're shooting with a little bit shallow depth of field that's one of those nice little extras and so this would be the critical factor here now the other issue is what lenses air using because if you're using slower, more traditional kit lenses maybe putting that money in a faster lands and one that could be upgraded so that if you do get a full frame sensor you can use on your system now as well as in the future, that would be the most sense for your money and where you'd want to spend it. And so I would say probably look at lenses first because in that case, generally what I think is a better choice is buying someone's is ahead of time knowing that you're going to go full frame rather than jumping full frame and realizing that you don't have the support and lenses to do what you need to dio because when you make that jump up to the body. You gotta have the lenses with it. You can use the lenses on any of the bodies in that sense.

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John Greengo - How To Choose Your First DSLR - Reference Guide.pdf

Ratings and Reviews


I have to thank John Greengo and the CreativeLive staff for another wonderful class. Mr. Greengo is a very good instructor (he has a nice Bob Ross ambiance), very knowledgeable and very technical with the camera and the terminologies. I am very grateful that he has material to download so I can continue to review and learn. I own a DSLR but I never truly understood the baseline technology. I am in the process of purchasing a new camera system and lens for some photography but mostly for filmmaking. With the knowledge I gain by watching this course, I can better choose and identify the features of the future cameras in my upcoming new passion. Thank you CreativeLive and Thank you Mr. Greengo. I am looking forward to attending future classes.


This was a great class. I already had an idea of the direction I wanted to go as I start my new business, but this class really helped me focus on the most important upgrades I need to make to my current system. I was particularly impressed with the visual graphics used to explain the technical functions of cameras and how those functions affect image quality and camera use. I would highly recommend this class to anyone who wants to up their camera system and I am looking forward to taking the classes that are specific to the camera systems I am using. I would love to see a class on image processing and getting the most out of editing software. Great Job! Glad I signed up for CreativeLive.

Bev Anne

Excellent course. I was happy to find out that I made a good choice when purchasing my entry level DSLR camera -- it does everything I need at the moment. I was also interested to find out that mirrorless is the wave of the future -- I really like the idea of the light weight because I am developing some arthritis in my wrists and when I am ready to move up in the future I will have great options. Meanwhile I also learned that there is an inexpensive lens that I can get that will upgrade my system enough for the immediate future. Thank you John Greengo for this informative class it was well worth the purchase price.

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