Homework Notes - Monday Jan 20

Video For Photographers: Shooting with a DSLR

Understanding resolution for video:

• Resolution can be changed at will in photography, videos can only be shot in two resolutions
• 1080 HD and 720 HD
• 1080 HD means the video is 1920 pixels by 1080 pixels 
• 720 HD means the video is 1280 by 720 pixels 
• Megapixels have nothing to do with resolution of video
• 1080 is about 2 megapixels
• 720 is about 1 megapixel
• Both 1080 and 720 look good on HD TVs 
• There is no huge advantage to one or the other, though the case can be made that 1080 can be easier to work with

Choosing a video frame rate:

• Video is typically shot at 30 frames per second
• Keeping it simple? - use 30 fps
• Video is just still pictures, 30 frame per second 
• Film is shot at 24 frames a second
• 60 frames per second is often used for sports or smoothing out videos
• Still not sure? Just try 'em out!

Understanding the challenge of shutter speed:

• Shutter speed choice is very different from video to still photography
• Slower shutter speed = blurred action
• Wide aperture and high shutter speed used to stop action
• 1/30th of a second is the slowest possible shutter speed if shooting at 30 frames per second
• the higher the shutter speed during video the more "stuttery" the video will look
• If you were shooting video with the intent of freezing the action for a shot a higher shutter speed would be useful
• Normal video is shot between 1/30th and 1/90th of a second
• Some believe the ideal shutter speed is 2x the frame rate

Getting the right exposure:

• No RAW in video, so exposure is important
• Manual exposure for videos is typically better than auto
• Auto exposure might change the exposure inappropriately, making the video flicker
• It is not a bad idea to take a photo and address the exposure before you even start shooting
• Due to the small range of shutter speed on video you might run into problems
• If you want a limited depth of field in bight lights you are going to have to use a dark gray filter to cut the light
• If light levels are low you have to change the ISO settings (because shutter speed can't go slower than 1/30th of a second)
• Fast lenses can help in low light as well
• Zoom lenses are not fast (they don't have a wide max aperture)
• Prime or single focal length lenses are good for video because they offer a fast max aperture
• This means they let in a lot of light