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I have decided to incorporate tips thread 2 with this one..
Here we have part 2 of my beginners tips.
This time i want to touch on ISO, shutter speeds and apertures.
Let me start by saying that this is rather difficult to understand let alone explain, but you WILL get to grips with it fairly quickly with a few test shots.
So take your camera out of its preset modes and never touch them again...
ISO (International Standards organisation).
I want to just 'touch' on this as it can be quite in depth.
This is the term that the speed of FILM is measured by. It used to also be called ASA (American Standards Authority, if i remember correct).
Do not confuse this with the speed of a shutter or lens, but they will effect each other.
During the days of film, they produced it so some were more sensitive to light than others. What this meant was that if you had a faster ISO then you could use a faster shutter speed, which was ideal for darker conditions.
The most common ISO film speeds were 50,100,200,400 (100 and 200 being the most common), it would go a lot higher than 400 (25-1600 and higher was available) but not really as common.
The lower the number the slower the film, the slower the shutter speed would be and the better quality the film and photo would appear.
The higher the number the faster the film, the faster the shutter speed would be, BUT you would end up with more grain (speckled bits in your image)
A slower film (low ISO) was great for scenics as it caught a lot more detail and would allow for slower shutter speeds for creative tripod work. A faster film (high ISO) was better for low light situations (like live club music) allowing you to get reasonable shutter speeds so you could hand hold your camera.
This standard is exactly the same on a digital camera as it was on the old film camera. The only difference is, is that you can change your ISO settings at any point, so you can go from scenics and bright light situations to darker situations easily.
Have a mess around with this. If you are in a dimly lit room that appears difficult to get a decent shutter speed without getting camera shake, bump up your ISO and watch your shutter speed get faster and faster.
THIS IS WHERE THE FUN OF PHOTOGRAPHY BEGINS
Shutter speed Priority (TV = Time Value).
Shutter speeds are usually measured in seconds (fractions of). As a 'rule of thumb' you can generally hand hold a camera with a shutter speed the same as the focal length.
So, if you use a zoom lens say 70 - 200, you should be able to hand hold the camera at 1/70th second (and faster) at the 70mm end of the focal length and 1/200th second (and faster) at the 200mm end of the focal length. Any slower and you may get camera shake and a tripod is recommended.
So if you zoom in and notice your photos are out of focus or have movement in them, check your shutter speed.
Take your camera out of the preset settings and pick TV to adjust the shutter speeds, but still allowing your camera to choose the right aperture to match the speed to allow hand held shots.
Shutter priority continued.
People want to know what speed is best for what photos they take when trying to be creative.
It all depends on what you take photos of...
For instance, a photo of a motorcycle race, some will just put it on the fastest setting to freeze the action. This is a great starting point to work from, and fine for bikes coming towards you, but not so good for side on shots as they can look very static. You need to have some movement in the wheels and moving background to give the impression of speed.
This will also help with correct panning techniques too. I have found that i get better results by pre-focussing on a point on the track where i know the bike will pass (usually in front of me), then follow the bike through the view finder panning it by just twisting my waist and pressing the button just before the bike enters the point i had pre focussed and keep panning through the shot. It takes practice, but you will get the hang of it.
These 2 types of photos dont really matter if your shutter speed is fast as there is not much movement in the wheels, and you can get a good sense of speed just by looking at the bikes. I pre-focused this too...
A panning shot like this needs a slower shutter speed to give the wheels and background movement...
This technique can also work for most other sports too, but the closer you are or the faster the subject is, the harder it is.
Your best starting off at a very high shutter speed 1/1000 second or so, and as you get better at catching the bike in the frame, reduce the speed down a bit at a time to about 1/200 or less to get some movement into the wheels etc.
Another good technique is to use a fast shutter speed (1/1000 second or faster) to freeze the action. you can get some great results with this...
Some cameras will allow you to use a slow shutter speed with a flash. This way you get movement within the frame, but then the flash goes off and freezes everything too. A tripod is best for this effect to work and the ideas can be endless with a bit of imagination. You may need to tell the camera to trigger the flash when you press the button or when the shutter closes (first or second curtain sync flash its sometimes known as).
With this shot i had a fairly long shutter speed of about 5 seconds or so to create the trails, then let the flash go off at the end to light up the inside of the car...
Aperture priority (AV = Aperture Value).
The aperture is made up from an iris, and is usually a series of micro thin blades in the lens that determine the amount of light entering the camera. They work a little bit like your eyes pupils.
They range from f1.8 to f32 for most consumer lenses. The lower the number the faster the lens. In other words the more light it lets through to the sensor. You can get an f1 (if you win the lottery).
The more light entering the camera the faster the shutter speed.
The aperture also depicts the depth of field too, in other works how much is in focus.
So, a smaller number (f2.8 for instance) means a larger aperture/iris, this will allow more light in, which in turn will allow for faster shutter speeds, but less depth of field, so not as much will be in focus.
The larger the aperture number (f32 for instance) the smaller the aperture, the less light will enter the camera, the slower your shutter speed will be, the more of the scene will be in focus.
This was taken using a 70-200mm lens set at 200mm from about 8' away.
The first one was taken at f2.8, 1/160th second.
This was taken at f11, 160th second...
And lastly at f32, 1/20th second...
The observant of you will notice that i hand held this at 200mm and at 1/20th second, when i already said that at 200mm the slowest should be 1/200th second. My lens has IS, which is image stabilisation that allowes for slower shutter speeds hand held.
So far so good? Well, to complicate things, this can also depend on focal lengths and distances from the subject. Basically, the closer you are to the subject and the greater the focal length, the more will be out of focus with a large aperture (like f2.8).
With the above photos, i was stood about 8' away, so at 200mm and f32 it still doesnt allow for everything to be in focus.
Now, set your camera to AV and see how it effects your shutter speeds when you adjust your aperture value.
All this may sound complicated, and it is..... to begin with, but keep messing around. Set you camera to AV and adjust the aperture and see how it effects your shutter speed. If the shutter speed goes lower than your focal length then you may get camera shake. Set it to TV and mess around with shutter speeds and see how it effects your aperture.
To recap...
(These can be read from left to right and right to left)
Small AV number = more light entering lens, smaller depth of field = faster shutter speed.
Large AV number = less light entering lens, larger depth of field = slower shutter speed.
Incidently, the quality of the Out Of Focus area of a photo is also known as the BOKEH (pronounced bock-er).
Again, if this has helped at all give me thanks and i will make a 'Tips 3' thead, and cover benefits of RAW, pushing and pulling your exposures and anything else you think people may need help on.
If anyone else has any tips or disagrees with what i have wrote then please say. |
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Author: Thug
2-12-2019 06:12:43
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