Quiz 4

Remember: Exposure is the amount of light which gets into the camera and is projected onto recording media (sensor).

Remember: The smaller the Aperture Opening (which is the higher F-number), the more Depth of Field you get. In this case F/16 is the smallest.

Remember:

Exposure (or amount of light which get into the camera) depends on Aperture, Shutter Speed and ISO.

Remember: Depth of Field is controlled by Aperture Opening. The smaller the Aperture Opening (which is the higher F-number), the more Depth of Field you get.

Remember: The bigger the aperture opening (smaller F-number), the more light you get.

Remember: The slower the shutter speed, the more light you get. Shutter speed of 15 (which is 1/15 sec) is the slowest shutter speed (which means that the shutter with this shutter speed remains open the longest).

Remember: The faster the shutter speed, the better it is able to freeze moving subject. In this case shutter speed of 500 (which is 1/500 sec) is the fastest.

Remember: The higher the ISO, the more sensitive to light it is. In this case ISO 3200 is the highest number.

Remember: The lower the ISO, the less noise you get.

Remember: The equivalent exposures let the same amount of light into the camera. The right answer would be f5.6 and 1/125s. In this case we closed down the aperture one stop – from f4 to f5.6 (this gives us one stop less light), but we used one stop slower shutter speed (which gives us one stop more light). So this way f4 1/250s = f5.6 1/125s

Here how it goes:
f2 1/500s = f4 1/125s – if we close down aperture 2 stops (from f2 to f4), we have to slow down our shutter speed 2 stops (from 1/500s to 1/125s) to get the same amount of light.

f2 1/60s = f4 1/15s – if we close down aperture 2 stops (from f2 to f4), we have to slow down our shutter speed 2 stops (from 1/60s to 1/15s) to get the same amount of light.

This is how it works:

f8 1/60 ISO 100 = f8 1/125 ISO200 – If I speed up my shutter speed 1 stop (from 1/60 to 1/125), I have to increase my ISO 1 stop (from 100 to 200) to get the same amount of light.

f8 1/250 ISO 800 = f8 1/125 ISO 400 – If I slow down my shutter speed 1 stop (from 1/250 to 1/125), I have to decrease my ISO 1 stop (from 800 to 400) to get the same amount of light.

This is how it goes:
If you change your aperture from f16 to f8, you will add 2 stops of light. To compensate for this, you will need to remove 2 stops of light by making your shutter speed 2 stops faster (from 1/60s to 1/250s). This way you will get the same exposure.

Remember: The wider the aperture opening (smaller f-number), the less DoF (less things in focus) it will give you, so for a blurry background you want to use wider aperture. In this case f2.8 would be the widest aperture. So the answer would be: ISO100 f2.8 1/1000

But be careful, the widest aperture in some lenses can give you too little DoF, so your subject might not be fully in focus.

This is how it goes:

The faster the shutter speed, the easier is to frieze the moving subject. The shutter speed of 1/1000s is the fastest, but it comes with f2.8, which will give you shallow DoF (less things in focus). This will not work for us, since we need more things in focus.
ISO 400 f8 1/500s – is the better option, since shutter speed of 1/500 is fast enough to frieze moving bike and f8 should give us more things in focus when f2.8 and f4. The only thing is that we have to sacrifice is ISO. But in most modern camera ISO400 is not a big deal in terms of noise.

Remember:
If your image is overexposed, it means that there is too much light coming into the camera. One of the ways to reduce the amount of light is to close down your aperture. In this case we have to close it down 2 stops, which will give us f4.

Remember: If you image in underexposure, it means that there is not enough light getting on the sensor. You can increase the amount of light by opening your aperture (which is the same as using smaller f-number), using slower shutter speed or higher ISO.

This is how it goes:

You can change your ISO to 100 or your Aperture to f8 or your Shutter Speed to 1/125 to get more light into the camera, which will fix underexposure problem. The answer is any of the above, but not all at the same time. It you make all those changes at the same time, you will add 3 stops of light instead on 1. This will make your image overexposed.