SM, that was a nice summary but I hope you are grossly overly pessimistic. With my level of ignorance, I belong in the beginners column, but I learned your 101 level of knowledge when I was about 12...
Good for you, I'm sure it serves you well. I'm decided to write that after trying to answer questions like "what is a stop" by people about to be talked into spending 4 grand on a kit to shoot their kids soccer games.I don't think it's grossly pessimistic to think a lot of people on this forum wouldn't understand much of what I put in this post I wasn't in anyway trying to put anyone down, at all. The fact of the matter is that there are a lot of people here, spending or contemplating spending a lot of money on photographic equipment that have never taken a camera off program. That doesn't make them dumb. Doesn't even make them bad photographers. One of the most talented photographers I've seen lately is a friends daughter, a 16 yr old girl on her high school journalism team who gets lost every time Program mode doesn't yield a sharp, well exposed shot. However, her eye for composition adn ability to see extraordinary things in ordinary objects leaves me feeling that with half my technical competence she would capture things I would never see...
OK, so far, but what happens next?.
Even if you know all that, how do you get well exposed shots?..
Exposure consists of 3 and only 3 variables..
1. The length of time that light is allowed to strike the recording media(shutter speed)2. The intensity of the light (Apeture)3. The sensitivity of the media (ISO).
You forgot the amount of available light, and the issue of adjusting for very bright or dark scenes that may fool the camera's meter (wedding clothing, snow, etc.)..
For aperture this is 1.4 - 2.0 - 2.8 - 4.0 - 5.6 - 8.0 -11 - 16 - 22- 32. The LARGER the number the SMALLER the lens openingand the less light comes in..
The reason for the factors of 1.4 is that light coming into a circle is a function of area, and aperture is a measure of width..
You can also remember the progression by remembering powers of 2, and then applying a factor of 1.4..
F/1 - f/2 - f/4 - f/8 - f/16 - f/32 4x change with each step.
F/1.4 - f/2.8 - f/5.6 - f/11.2 - f/22.4 (ditto)..
Good point. I was referring to the 3 variables controllable by settings on the camera. Also didn't want to get into flash, though it does make available light a controllable variable. About metering....Important but I think I threw enough out there without going into how a camera tries to turn black and white both into 18% grey....I'll let you figure out how to explain that one ..
You have to buy the book for that......
Well, I wish that could be explained in a few pages. But understanding the shutter speed and aperture settings on your camera and how they relate to each other and what you are seeing on the back of your camera LCD is a good start..
Knowing that if your shots look too dark, that either means that there is not enough light for the shutter speed, aperture , ISO combination you (or the camera's program mode) have chosen OR that the camera's meter is being fooled by an overly light or dark scene. Understanding these settings and being able to take the dial off Program to M and adjust the shutter speed or aperture or increase the ISO if necessary, to get the results you are looking for will improve your photos. Explore, digital photography has given photographers a great learning tool ...instant feedback and a delete button. We used to learn by shooting a frame on film, recording the exposure, shooting another, etc...then waiting to develop film to match up to our notes. But this tool is only effective if you don't let the new, sophisticated camera do all the thinking for you...
I'm noticing this has created a weird phenomenon that you would have NEVER seen 10 years ago. People are engaging in technical discussions about photography on these forums, that know all kinds of information about sensor technology, noise, pixel pitch etc., they can tell you all about the various camera models and their relative pros and cons, yet don't even understand the basics of light and photography. People are trying to figure out whether to invest in a $1700 VR lens over a $1000 one without even understanding the relationship between shutter speed, focal length and camera shake..
I don't think that all the technical discussions are so weird, but are there really people here who know more about sensors and noise than basic exposure? I've never seen this happen and find it a little hard to believe. Who would start learning about a camera from the outside in?..
Suppose you try to explain to the readers how to put this basic information to practical use..
For example, what is a good exposure (what should you "aim" for)?.
Just what does the lightmeter "make" of the scene?.
What about Dynamic Range?.
How do you get the "best" out of the dynamic range you have?..
You probably caught me on an overstatement. I think the phrase I should have chosen to really convey what I meant was "are more concerned with understanding sensor technology....etc." rather than "know about it"..
Technical Geeks and Engineers. That be me. I know much more about sensor technology and the electronics inside the camera than I probably will ever know or understand about exposure. Exposure seems to be something you really need to comprehend intuitively which is sometimes hard for us technical types to grasp. However, I watch and I read and it cracks my anal thinking processes just a little more each time and therefor I am very thankful for those of you who share your wisdom and experience in the hopes that some day I just might get it. Thanks and please keep explaining...
Your not a 20 year Pro trying to stress me out are you? well....I'll bite anyway.
I'm not sure how to answer that. My objective was to simply shed a little light and pique a little interest in someone to take that dial off P (or the little mountain or running man) and see what A, S and M do..
A is aperture priority, meaning that you set an aperture and the camera will meter and choose a shutter speed to get what it thinks is an accurate exposure. This mode will usually result in a pretty accurate exposure since the camera has a very wide range is shutter speeds to choose from. It may, however result in a blurry image if it chooses a shutter speed too slow to freeze a moving object or avoid camera shake without a tripod..
S is the opposite. Shutter Priority. You choose the shutter speed, camera chooses aperture. This is a little more limiting for the camera since it has a fairly limited range of f stops on the lens. If you choose a shutter speed that is too slow for the minimum aperture or too fast for the maximum you will get an under or over exposure. Usually the apeture value will flash in the viewfinder if this is going to happen.
Other than a very few exceptions, like shots to show motion, or time exposures, a good thing to remember is that a slower shutter speed can really can't help a picture (other than gettng it to the proper exposure) but it can hurt. If you want to freeze action, depending on speed and lens, you really need to be up in the 1/500 range or higher. To avoid camera shake the old rule is a shutter speed of 1/lens length (without IS/VR).
M is Manual mode. you set shutter speed and aperture. The camera will only "suggest" an exposure in the meter..
What is a good exposure? One where white is white without losing detail, black is black without being a blob, and anything in between looks like it's supposed to. How do you get one? Well about the only guideline I know other than trusting a light meter is the "sunny 16 rule" where subjects in bright sun are exposed at equivalent to f16 at a shutter speed of 1/ISO. That's not too helpful so I would start out by trusting what your meter says, spot metering a neutral color area is more accurate. Metering a 18% grey card even more so. Know that if the subject is white your meter will suggest an underexposure of a couple stops, if it's black it will suggest an over exposure. If you put your camera on Manual, there should be an exposure meter in the view finder that will move as you adjust your shutter speed or aperture.
As far as ideal shutter speed aperture combination, that is just too subject dependent. Some tips: if you want a shallow depth of field (subject sharp, background and foreground blurry) for say a portrait, or flower shot, open up the lens to at least the 4.0 range. Adjust shutter up to get correct exposure. If you want everything in view sharp for something like a landscape stop the lens down to at least f11 or f16 and lower the shutter speed to the right exposure. If you are shooting a fast moving object, expect to use high shutter speeds or 1/500 or more..
Dynamic Range. Look outside on a bright day and notice the detail your eyes can see in but the brightest parts of the sky and the deepest shadows under a tree. Our eyes are capable of seeing a tremendous range of intensity of light. Cameras are not (well my S5 Pro is but this isnt an advertisement ). If you expose for the sky, the shadows will be too dark, expose for the shadows, the sky will go white instead of blue. What do you do? Short of using HDR techniques in software post processing, which I'm not going into, you shoot for the middle and hope you retain detail in both as much as possible. This is why DR is important and why some of us sacrifice resolution and shooting speed for it...
Well, of course it's a long subject, and people spend a lifetime trying to master it. I'm just a beginner myself..
It seems, trying to take photographs is a little like trying to cover a large table with a small table-cloth: you can't cover all of it at the same time. Decisions have to be made as to what is the most important bit to cover at any given time..
Using digital and post-processing allows one to "stretch" the table cloth, or to put it another way, make a collage out of several successive attempts at covering different bits and combining several shots (through the "magic" of digital processing into one single picture. Unfortunately, this often produces a strangely "unreal" result: something like face-lifts or breast implants..
Unfortunately, an impression gained by many "amateur" photographers wishing to improve may be that a more expensive camera will necessarily provide them with a "better" result than they would get with their P&Ss. However, the "expensive, top of the range" DSLR often has much the same (restricted) dynamic range (especially the higher the ISO used) as their "humble" P&S: disappointment results, as may be gathered from many of the threads in these forums..
Actually, it is a truism that it's not the camera, it's how you use it that counts: as may be seen from the many breathtaking pictures resulting from pinhole cameras, constructed from matchboxes, toilet rolls, and biscuit tins, posted on the web..
I'm sorry...I only have questions and no answers...
Thanks for your enlightening post SMphoto..... I personally reckon some of the replys to it were unduly harsh. As a new DSLR owner you are exactly right in what you say. I have always had a P&S camera & have taken some great shots over the years but now I have decided to move into the next realm , the world of DSLR. I for one can tell you the technical differences of a multitude of cameras from my pre purchase research, but now I actually own one I am realizing the hardest thing to understand & master is exactly what you said.... Exposure & the relationship between shutter speed, aperture & iso.
My first question to this forum was actually going to be, "what would a good starting point be for shooting skateboarding (assuming good daytime light) as far as shutter speed aperture & iso goes?" You have indicated that 1/500 is a good starting point for shutter speed for fast moving subjects, if I started with that & iso 100(maybe, for daytime?) & checked the results via the histogram, then adjusted the aperture to get it right (in the middle of the histogram), would that be the correct way to nut it out? Any setting suggestions would be appreciated.... Thanks again for the informative post.. One other thing, if that dude is a beginner & learnt this when he was 12................. I'm in trouble...LOL............Sneaky.....:)..
...I'm noticing this has created a weird phenomenon that you would haveNEVER seen 10 years ago. People are engaging in technical discussionsabout photography on these forums, that know all kinds of informationabout sensor technology, noise, pixel pitch etc., they can tell youall about the various camera models and their relative pros and cons,yet don't even understand the basics of light and photography. Peopleare trying to figure out whether to invest in a $1700 VR lens over a$1000 one without even understanding the relationship between shutterspeed, focal length and camera shake..
From a cynical perspective I should discourage you from this attempt at mass education as I hope to buy their quality used equipment from them when they give up!.
But more seriously I think you are right. I remember reading books on exposure at age 10 and I have been using SLRs for decades and DSLRs for approaching a decade but there is now a flood of people coming to this site who do not understand the first principles but own a $1500 camera. It is like Groundhog Day. I find myself answering the same question daily and often near identical questions are only four posts apart..
Another problem that is generated by this phenomena is the "My camera won't work" type question. Because the OP is on a totally different knowledge plain from those who try to help there is no meeting of minds. An example was the OP who did not realise you had to look through the viewfinder and thought his camera was broken when he got no picture on the LCD when he switched on and tried to focus..
All of which leads me to conclude that there is a crying need for a FAQ facility on this site. I do my best to help as do others but I get a bit cross at the lack of self help or appreciation that this may be an identical question to the one posted and answered only minutes ago..
*Nikon* D Eighty + Fifty - Other equipment in Profile.
Try not to get cross. I'm sure there a lot of people like myself who have read the previous post but will read the next one a few minutes later knowing they will probably pick up something new. Sometimes it's only a minor point that gets clarified but little by little we're starting to understand photography and the camera. We also appreciate the generousity and perseverance it takes to be a teacher...
~ Exposure consists of 3 and only 3 variables.~ 1. The length of time that light is allowed to strike the recording media~ 2. The intensity of the light (Apeture)~ 3. The sensitivity of the media (ISO).
I know you were sticking to the three gadgets, not the four variables (and quite well done), but I thought I'd throw in a shameless plug to my writeup on this topic anyway..
I refer to the FOUR variables as the "LAST" Principle. Light, Aperture, Sensitivity, Time. To maintain exposure after doubling any of these, you must halve something else. In automatic modes, the camera will do exactly that. Each of the four variables will control something else (shadow, focus, noise, action); that's how you choose what needs to be changed to achieve the shot you want..
[ e d @ h a l l e yc c ] http://www.halley.cc/pix/..
Exposure seems to be something you really need to comprehendintuitively which is sometimes hard for us technical types to grasp..
Pretty much everything in photography is that way..
Photography is not a scienceit's an art or at least a craft. Good photos cannot be calculated, they cannot be computed, they cannot be engineered..
The transition from film to digital hasn't changed that. But digital photography *has* brought in a number of people who insist on trying to understand photography from a mathematical standpoint. This might be a personally entertaining diversion, but it doesn't really have much at all to do with taking better pictures..
What really strikes me is how reluctant so many of these "photo engineers" are to even *consider* empirical data. Experimental shots are free, but they'll sit and fuss over formulae for hoursand post questions and hypotheses on the forumsrather than go take a few test shots and see what they get. ..
For those who would like a book to build on SMPhoto's lucid introduction, here's a title: _Understanding Exposure: How to Shoot Great Photographs with a Film or Digital Camera (Updated Edition)_ by Bryan Peterson.
WillWill PrattBarrick Museum, UNLV..
Insight. My first question to this forum was actually going to be,"what would a good starting point be for shooting skateboarding(assuming good daytime light) as far as shutter speed aperture & isogoes?" You have indicated that 1/500 is a good starting point forshutter speed for fast moving subjects, if I started with that & iso100(maybe, for daytime?) & checked the results via the histogram,then adjusted the aperture to get it right (in the middle of thehistogram), would that be the correct way to nut it out?.
I'm a newbie myself but I'll try to answer your question with my limited knowledge. Two ways you can do this:.
1. Easier way: set your camera to Tv or S (i.e., shutter priority), and change shutter speed to 1/500 or faster. Set ISO to Auto (if your camera has such a setting) or set it to the highest ISO where noise doesn't bother you (with an SLR you should be able to get clean pics even at ISO 400 or even ISO 800). The logic of setting the ISO as high as practicable is to allow you to use higher shutter speeds. If it's really bright outside, you can adjust ISO to a lower sensitivity with less noise..
As for aperture, with shutter priority mode, the camera chooses that for you. It may be that the exposure isn't correct (e.g., whites look gray, or blacks look gray) in which case you can adjust exposure compensation upward or downward until the subject is properly exposed (in daylight, you may exceed the dynamic range of your camera - in which case, just expose the subject correctly or in the alternative, adjust exposure so that there are no blown highlights, then use post-processing to "dodge" and "burn" i.e., adjust exposure selectively in different parts of the picture)..
As for the histogram, unless it's an RGB histogram, you're may be better off relying on what you see. Otherwise, you may clip a channel and change the hue unintentionally. Also, my understanding is that getting the histogram in the middle is not as important as making sure there are no clipped highlights or lowlights (or color channels)..
2. The "harder" way: set the camera to manual, do as above, except you also choose the aperture..
Besides the basic technique above, there are many ways of shooting sports. For example, panning at slower shutter speeds (to keep the subject reasonably sharp while the background has motion blur), using a rear curtain sync flash (also for motion blur), multiple exposures (if your camera is capable of it, or through post-processing), etc...
This thread should be frozen and made sticky. Unless there is a policy against freezing threads and making them sticky.Tom..
Thank you for you comments. I knew going in I would get some "stop wasting my time, I know this stuff" comments, but know one needed to keep reading if it didn't apply to them. I'm glad you round some of it useful. If you have good daylight, I would probably set the ISO to 200 or 400 depending on the camera. Most DSLRs made in the last 2-3 years can handle up to 400 without much noticeable difference in noise. I would probably set the aperture to 5.6 to start.
Try 4.0 or faster if your lens allows and 8.0 also to see which DOF you like best. 5.6 or 4.0 should allow you to shoot a pretty fast shutter (around 1/2000 in bright sun 1/500 in moderate overcast). Heavy clouds you are probably going to have to increase ISO to 800-1600 or get down in the 2.8 aperture range...
Well, I'm the guy that got something out of that!.
I know about CCD vs. CMOS, and Bayer vs. Foveon pixel arrays, and chroma vs. luminance noise, and the relative merits of one kinda shake reduction system versus another... and really I am sick of it..
I think my unique position here is that I have more time than money, and have to make that money stretch. DPreview is a great site, and Mr. Askey's reviews are so in depth, that they answer every conceivable question a beginner could want to know... which number all of about three things. Generally rotating around cost, megapixels, and how wicked cool the camera looks..
Unfortunately, the reviews raise a million more questions... which suck... Statements like, " theres alot of chroma noise at high ISOs... why couldn't it be luminance noise, like on the Nikons..." or some such throwaway sentence in the conclusion of a review that makes me wonder what chroma noise is and what it will do to me..., and next thing you know, theres a million little nagging things to track down and figure out. Some more important than others.... all of which mean nothing to the neophyte at first...
For those of you surprised that someone could know these technical aspects, without the fundamentals of photography, just consider this... now that they have lowered the price to purchase prosumer and consumer SLRs, you will all have to contend with a generation of photographers with no experience with the three fundamentals of exposure... because they are coming from point and shoots with no user control over these functions. Like myself..
So in any case, thanks!!!..
For a "beginner" with only questions, you seem to have a particularly acute grasp on the subject. I couldn't have said any of that better. One thing to remember though; manipulating an image during post processing to correct exposure and increase dynamic range is nothing new. Digital did not bring this about. Custom prints from film have for a long time used dodging and burning the same way we selectively lighten and darken sections of digital images with Photoshop. Selenium toning was often used by artists like Ansel Adams to increase dynamic range by a stop or more (It's often thought that Adams was as much of an artist in the darkroom as he was in the field). Digital post processing just expanded the tool set...
Thank you for the comments. If everyone in your shoes would stop worrying about megapixels, noise, and the MTF scores of professional versus consumer lenses for a few months, and learn about how to take good pictures, their photographs would improve immeasurably...
One thing to remember though; manipulating an image during postprocessing to correct exposure and increase dynamic range is nothingnew. Digital did not bring this about. Custom prints from film havefor a long time used dodging and burning the same way we selectivelylighten and darken sections of digital images with Photoshop.Selenium toning was often used by artists like Ansel Adams toincrease dynamic range by a stop or more (It's often thought thatAdams was as much of an artist in the darkroom as he was in thefield). Digital post processing just expanded the tool set..
Very good and pertinent observations...
I am seconding and thirding the thanks!.
I had a professional photographer for a boyfriend in the dark ages and my own little Oly point and shoot zoom, right before digital took over. I had a floating sort of acquaintance with all of this but my artist head was actually better at grasping the concepts of a digital film and little electrons capturing images like film used to... better than actually sitting down and trying to remember ANY numbers. The problem with all this is that there are Numbers involved!.
I have a good photo editor and a good eye but tonight is the first night in all my 6 or more years and three other digital cameras that I actually figured out what the manual settings were for on the new one..
I called the old beau up for the EXACT information I just got here. The CONCEPT is working but I fear all the telling me in the world will not make up for the hours I spent this evening taking bad photos and moving through the stops in the new boyfriend's living room, just running through the variables..
I use my camera for reference for my paintings and have ALWAYS told people I am not a photographer, although I am great at making composition, I just found out my snapshots on little note cards were outselling the prints of my artwork so I thought for the sake of my income, it was time to figure out how to MAKE the pictures, rather than just FINDING them at the end of my shoot..
I do need to have a few pages of PHOTOGRAPHY FOR IDIOTS and thumb through one page at a time to have it sink in, but this info was PRECISELY the answers I needed.Thanks for putting it here simply and in the most amazingly timely manner!!!dj*..
Chris Elliott wrote:.
All of which leads me to conclude that there is a crying need for aFAQ facility on this site..
There is one, it just hides behind a different name - see Learn/Glossary on the main menu. A woefully underused resource!..
I have the impression that a lot of problems with exposure arise because people don't quite understand what the camera does with the value the meter gives it, and that the key insight is that the camera assumes that whatever the meter reads is mid-grey, and if it is, in fact, lighter or darker than that the overall scene exposure will be "wrong". Best book for this? Adam's "The Negative"...
THAT is the problem I am having next....
I am shooting right out of auto for a few days to see what I need to do. I live in INCREDIBLY bright Arizona and am still trying to figure out how to prevent burning lights. If it averages, that is meaning the shadows are too rangy for it. so.... is BEACH or SNOW going to get the most details for me in the lights? I have to figure out how to reset the whole thing, as I have tweaked some of my manual settings out of the ballpark and after an evening in low light, the day was a washed out fry.I didn't have enough color or contrast to play in the computer..
My new f8000fd.... is there any way to override one or more of the settings so I can get a lower average shot? I do use the auto focus and try to choose a darker spot and it is making a bit of difference, but still the whites come out too white?Is this a new question.... probably...
Every photographer I know has it in his or her library....
Image control:Zoom outZoom 100%Zoom inExpand AllOpen in new window..
Did you mean S8000fd? otherwise I don't know what camera you are talking about. If so, it looks like it has full manual control, as well as a spot meter..
Don't confuse the fact that your camera is over exposing really bright scenes with the discussion above about meters being calibrated for 18% (middle) gray. If you shots were suffering from this, then your white scenes would be too DARK, not light. In other words, the camera meter sees white or black and tries to make them gray. My general rule of thumb is that camera meters are tricked by about 2 stops by black or white subjects. Whites will be a dull light gray, and blacks will usually come out a dark brownish gray with no compensation. I would say that the meter in the S8000fd is trying to deal with a really bright scene and just not doing a very good job.
Try doing this: Set the camera to Shutter Priority. If you are outdoors, and the ISO is set low, like 100-200 try starting with 1/500. Look to see what aperture it selects for you. If it's sunny I am gonna guess it will be around f8 depending on ISO. If you are getting blown out highlights, try then moving to full manual and setting the shutter still on 1/500 but manually set the aperture 1-2 stops up to f11 of f16 and see what happens.
This will teach you less, but there is probably an EV setting somewhere that will let you override the auto exposure by setting exposure compensation to -1 or -1.5 stops...