Introduction to Digital Photography Session 2 Camera Mechanics

Introduction to Digital Photography Session 2 – Camera Mechanics Scott Hull 6/27/2019 Learn the rules like a pro, so you can break them like an artist. Pablo Picasso

Agenda � Exposure � Terms � Camera Types � Camera Parts � Sensors � Crop Factor � Exposure Modes � Focus Modes � Metering Modes � File Format � White Balance � Lenses � Image Stabilization � Memory � Filters Flash � Gadgets � Display Options � Find the Buttons We will NOT get through all this in one hour, but I’ve includes all of the slides for your reference.

Where are you as a photographer? 0 20 40 60 80 Never took a photo � Everybody is somewhere between 1 and 99 � As skills develop, you will want more capable 100 Nat. Geo. every month equipment � Know where you are now, where you want to end up, and how to get there (usually practice)

Exposure has three components �Settings are all about what you want in the final product, but they’re usually a compromise �Shutter Speed (1/xxx sec) Faster to freeze action, slower to blur �Aperture (f/# ratio); higher # is smaller opening Larger aperture, blur foreground and background; smaller aperture, sharper foreground and background # is an indication of how much depth you will get �Sensitivity (ISO) How low can you go? Stay as low as possible Higher sensitivity means more noise

Exposure examples Combo of aperture, shutter speed & sensitivity 1 f/8, 1/8 s, ISO 500 4 f/4. 5, 1/20 s, ISO 500 2 f/29, 1/2 s, ISO 500 3 f/8, 1/20 s, ISO 1600

Another way to look at exposure 1 2 3 4 Brighter Darker Adding or subtracting stops of SHUTTER SPEED, APERTURE, or SENSITIVITY can be used to change the overall exposure, or to affect the appearance of an image (depth of field, motion, etc. ).

Stops �A whole ‘stop’ is a change in the amount of light by half or double 1/250 sec 1/125 sec 1/60 sec 100 ISO 200 ISO 400 ISO f/4 f/2. 8 f/2 �Aperture numbers change by a factor of 1. 4 Square root of 2, since double the light is 2 x area Area of a circle is π r 2 : √ 2=1. 414 is the change in diameter �Most cameras now also use partial stops

Good Summary Chart

Terms � Sensitivity (ISO = ASA) The sensitivity of the CCD sensor chip � Aperture (also known as f-stop) The diameter of the lens opening � Shutter Speed The length of time that the shutter is open � White Balance The color correction for the light you are collecting � Optical vs. Digital Zoom Optical zoom is where the lens moves to expand or contract the image Digital zoom is a marketing tool – basically just cropping � Live View The ability to view the image on the display while you compose the shot

Camera Types “Pocket” Camera DSLR Digital Single Lens Reflex “Point and Shoot” Compact ILC (Mirrorless) Interchangeable Lens Compact

Camera Parts �All digital cameras have: Lens Shutter release Sensor Computer Display screen Battery �Most also have: Viewfinder Built-in flash ¼ - 20 tripod mount �Some Have: Hot shoe Mirror / prism Beam splitter Grip Selection dial(s)

What’s inside a DSLR? Pop-up Flash Prism Hot Shoe Mirror View Finder ¼ - 20 Tripod Mount Lens CCD Sensor Shutter

Mirrorless camera advantages �Less vibration �What you see is what you get Adjust brightness before taking the shot See the depth of focus through the viewfinder Focus zoom in viewfinder �Review your shot instantly in the viewfinder �Playback with less glare �Combine with a touch screen Quickly designate the focus point Easily move around zoomed images in playback Quickly change settings by touching the setting

Sensors (size does matter) • Blue box is 35 mm film frame • The difference (white area) is the crop factor

Crop Factor �Reported relative to 35 mm film �Same focal length lens that was used on film camera now focuses onto a smaller sensor �The sensor image area becomes expanded when viewing, so it is effectively magnified �Because of this, a 100 mm lens on a Canon APS-C camera gives the same magnification image as a 160 mm lens would on 35 mm film

Camera Settings �Exposure Modes �Shooting Modes �Scene Modes �Focus Modes �Metering/ Exposure Compensation �File Type/ Image Quality �White Balance �Playback �A whole book full of others – read that book! (the User’s Manual)

Exposure Modes Auto Camera selects everything: aperture, shutter speed, focus, flash Fully Automatic all of it, with no overrides Usually works well, sometimes disappoints Program Camera picks aperture & shutter speed; focus can be overridden Aperture Priority Semi. Automatic User picks the aperture, camera picks the shutter speed to match Often the preferred go-to mode for experienced photographers Shutter Priority User picks the shutter speed, camera picks the aperture to match Fully Manual User gets to/ has to pick all settings

Shooting Modes �Single shot �Burst High/Low speed bursts �Self-timer �Mirror lock-up �Remote control �Bulb �Bracketing for HDR

Scene Modes �Portrait �Landscape �Night Scene �Night �Sunset �Fireworks �Food �Documents �Beach/Snow �Underwater Portrait �Sports �Indoor (4 options) �Macro �Snow �Self Portrait �Close-up �Museum �Backlight �Panorama �Candle �Probably many more…

A Few Common Scene Modes � Sports Increases ISO, opens aperture, for faster shutter speed � Landscape Chooses narrower aperture, for longer depth of field � Portrait Chooses wider aperture, for short depth of field � Night Portrait Long exposure for background, plus flash for faces � Fireworks VERY long exposure (seconds) – should use a tripod � Beach/Snow Compensates for bright reflections by increasing exposure � Night Scene Increases ISO, for greater light collection, no flash

Metering Modes � Multi-zone (evaluative, matrix) � Evaluates whole scene (60% center, 40% other) Center-weight (partial) Gives preference to exposure of central (~10%) area � Spot Gives preference to small (~2 -3%) area in the center Gives precise control over exposure in a specific spot � Half-press the shutter release to hold the exposure � Exposure Compensation: shifts the exposure brighter or darker

Focus Modes �Autofocus on most new cameras is pretty darned good Even experienced pros are starting to use it instead of always manually focusing Still not always perfectly crisp Doesn’t work for all situations – moving subject �Very dependent on high contrast areas �Focus point can usually be defined on DSLRs �Might still need to tweak the ‘sweet spot’ �Manual focus on pocket cameras and point and shoots is difficult, if possible

Focus Modes, continued �Single Shot Autofocus �Continuous Autofocus �Single/ Continuous with manual tweaking �Manual Focus �Live View focusing aid Magnifies the Live View image Mirrorless offer this in the electronic viewfinder

Files/ Image Quality �RAW vs. JPEG RAW is all of the data, straight from the sensor ▪ Largest files, most flexibility later, and highest resolution JPEG is processed and compressed before saving ▪ Compression losses occur each time it is saved ▪ Usually several levels of compression available �Why not just maximize everything with RAW? Olympus E-5 Example (12. 3 MP camera) ▪ RAW file: 12. 4 MB, High quality JPEG: 5. 3 MB ▪ Little discernible loss in image quality until you zoom in ▪ In fact, RAW initially looks much noisier at high magnification Memory cards are big, but not infinite capacity RAW is also not as portable between viewers

White Balance �Colors change based on the type of light Light brown shirt in incandescent light can look green in fluorescent light Even sunlight vs. shade makes a difference �Image is interpreted differently based on settings �Auto white balance is pretty good ~98% of the time �Check your display frequently, and change the WB if necessary �RAW images are not corrected, so you can change it later if it was incorrect �Most DSLRs can also set WB manually for unusual situations

Lenses � Built-in vs. interchangeable Depends on the camera type � Fixed vs. zoom Fixed is typically lighter and has higher image quality Zoom is more flexible � Cheap vs. expensive More expensive lenses have more elements, better coatings, wider apertures, heavier weight � Macro capability Highly detailed close-up images � Teleconverters Goes between camera and lens to produce 1. 4, 1. 6, or even 2. 0 x the focal length

Zoom Lens Cautions � A ‘wiggle’ of only 0. 03° will cause the image to move by 1/8” at 20 feet With a 50 mm lens, you may not see that With a 400 mm lens, it is 8 times bigger, and very noticeable � Zoom lenses are also usually unbalanced when hand held More likely to get that 0. 03° wiggle - or more � General rule of thumb for hand-holding an exposure: Shutter Speed < 1/Focal Length � They also tend to have smaller maximum apertures, leading to longer exposure times � Tripods help, but faster shutter speeds are more practical Tripod pointing is awkward and slow Faster shutter usually means higher ISO, though more noise � Thus, the driver for more expensive, “faster” zoom lenses

Image Stabilization � Uses tiny accelerometers to detect movement � Optical Image Stabilization Lens shifts the optical path, to stabilize the image Unique to the lens; extra $ for each lens Canon, Nikon, some Sony, Panasonic � Sensor shift Sensor is moved to stabilize image Works with all lenses, even old film lenses Olympus, Pentax, some Sony, Konica-Minolta � Digital Image Stabilization Used in some video cameras Computer changes the pixel region from frame to frame � Performance is rated in equivalent stops improvement � Turn image stabilization OFF when using a tripod

Filters � Ultraviolet Mostly to protect the lens Cheap, and nearly invisible in the image � Polarizer Reduces glare and reflections; great for rainbows Rotate for best effectiveness � Infrared Sees heat, for an ‘other-worldly’ effect � Neutral Density Reduces light, without shifting colors, for longer exposures � Color Highlights individual colors � Gradient Neutral density on one end to clear on the other Great for darkening skies

Memory �Most have two types of memory Internal – holds the picture right after you shoot Removable cards– for downloading to a computer �Card formats Limited by the camera Compact Flash – bigger, faster, often cheaper Secure Digital – SD, mini SD, micro SD, SDHC, SDXC �Make sure you don’t over-buy: check the manual

Flash �Obviously used to brighten a scene �Flash power is determined by the Guide Number GN = distance x aperture, at a specific ISO Example: 18 m at ISO 200 (Olympus E-5 internal) Means that at f/5. 6 and 200 ISO, anything beyond 3. 2 m (~11 ft) will not be fully illuminated �External flash GN is typically about 30 to 50 Can be moved off-axis, to control shadows Many are remote triggered; can use multiple units

Gadgets �Tripod �Shutter release �Remote control �Monopod �Camera Bag �Lens caps �Spare batteries �Spare memory cards �Reflectors/ diffusers �GPS data tagger �The list goes on and on…

What next? Now that I figured out my camera and I’m taking great pictures, I have a bunch of pretty files. What can I do with them? � Photoshop / Post-processing If you think they look great now, just wait… Elements has the same basic tools at a lower purchase price � Prints Costco does a surprisingly good job cheap Probably not worth getting your own printer ▪ Usually clog up if you don’t print a lot of pictures � Create a photo book about a subject (cheaper than you think) Online software and Elements both make it pretty easy � Post them online Recommend a Flickr free account Photo Club Flickr site – we want to see what you’ve done! Facebook, other social media

Recommended References � Your camera User’s Manual – read it! Download it for easy searching Carry it in your camera bag for reference � Web sites www. DPReview. com www. learnmyshot. com www. photoextremist. com � TV show Wild Photo Adventures http: //www. wildphotoadventures. com/ � Magazines Digital Photo Outdoor Photographer Lots of good British magazines

Button, button, who’s got the button? Power Switch Shutter Release Exposure Compensation Playback Live View Diopter Adjustment Lens Alignment Mark Lens Release Button Depth of Field Preview AF Point Selection Auto-Exposure Lock Aperture Adjustment Shutter Speed Adjustment Sensitivity Adjustment Self-Timer Continuous/ Sequential Shooting Erase Flash Adjustment White Balance

Backup Slides

Waterfall at various shutter speeds 1/800 � � � 1/200 1/3 Shutter Speed in Seconds 1 Set camera to Shutter Priority Mode (usually “S” symbol) or manual (“M”) For slow shutter speeds, go with higher f/# to let in less light (f/big number) For extreme cases, or sunny days, put an ND filter on your lens for less light For slow shutter speeds, use tripod or set on a rock Use a remote or self-timer to eliminate camera shake of pressing button http: //en. wikipedia. org/wiki/Shutter_speed 37

What Is Aperture? � Diameter of the lens opening � Expressed as a ratio of the focal length to the diameter (f-stop) � Smaller f-stop number = larger diameter 11/13/2013 Goddard Photo Club 38

Aperture vs. DOF Source: Fredrik Silverglimth, http: //www. tutorial 9. net/tutorials/photographytutorials/depth-of-field-in-photography/ 11/13/2013 Goddard Photo Club 39

Pixel Size determines light gathering ability Camera Nikon D 40 Pixels Sensor Size Pixel Crop (MP) (mm) (pixels) Size Factor (µm) 6. 0 23. 7 x 15. 5 3008 x 2000 7. 9 1. 5 X Nikon D 200 Nikon D 90 Canon 450 D Canon Rebel T 2 i Canon 60 D Olympus E-5 10. 0 12. 3 12. 2 18. 0 Canon A 95 Canon Power. Shot SX 150 IS 23. 6 x 15. 8 22. 2 x 14. 8 22. 3 x 14. 9 3872 x 2592 4288 x 2848 4272 x 2848 5184 x 3456 6. 1 5. 5 5. 2 4. 3 1. 5 X 1. 6 X 18. 0 22. 3 x 14. 9 5184 x 3456 4. 3 12. 3 17. 3 x 13. 0 4032 x 3024 4. 3 1. 6 X 2 X 5. 0 7. 14 x 5. 36 2592 x 1944 2. 8 14. 1 6. 17 x 4. 55 4320 x 3240 1. 4 ----- Smaller pixels mean less light, and more noise, especially in low light

RAW vs. JPEG Olympus E-5; 12. 3 MP camera (MD Renaissance Festival, 2011) RAW: 12. 4 MB JPEG: 5. 3 MB

Exercises (mostly for DSLRs) � Depth of Field Select a subject separated from a detailed background, or an inclined floor � � � (grass or carpet) Use manual focus on the subject and aperture priority mode Shoot a set of images at each of the whole stops (2. 8, 4, 5. 6, 8, …) Compare the area in focus in each Repeat, but changing ISO by full stops and keep constant f/8 Notice where the image starts to get grainy for your camera Repeat, but changing only the white balance Which image matches reality? Did Auto WB pick correctly? Speed Use manual focus and shutter priority mode Focusing on the street, hold your camera steady, and shoot images of moving cars at 1 sec, ½ sec, ¼ sec, … to the fastest your camera will go Compare the ability to stop the action vs. shutter speed Also notice what happens to the steady background in each shot Do the same thing while panning

More Exercises �Minimum focusing distance Take a picture straight-on of a newspaper page, at your lowest zoom focal length ▪ Move closer, until the auto focus won’t focus any more ▪ Repeat at the highest zoom focal length ▪ Compare the highest magnification and the working distance �Image stabilization Hand-hold, without IS, in shutter priority, and take longer and longer exposures of the same sharp subject ▪ Where does the image get soft? ▪ Repeat with IS on, if you have it ▪ Repeat at different zoom focal lengths

Exposure Review Sunny 16 Rule f /22 f/ 16 More Depth of Field -----> f /11 f/ 8 f /5. 6 ISO 100 f /4 f/ 2. 8 f /2 f/ 1. 4 1/4000 1/2000 1/1000 1/500 Stop Action 1/250 1/125 1/60 1/30 1/15 1/8 1/4 1/2 1 Tripod Zone On a sunny day, at f/16, the shutter speed is 1/ISO

Exposure Review Sunny 16 Rule f /22 f/ 16 f /11 More Depth of Field -----> ISO 50 ISO 100 f/ 8 ISO 200 ISO 400 f /5. 6 ISO 800 f /4 ISO 1600 ISO 3200 f/ 2. 8 ISO 6400 f /2 f/ 1. 4 1/4000 1/2000 1/1000 1/500 Stop Action 1/250 1/125 1/60 1/30 1/15 1/8 1/4 Tripod Zone 1/2 1 On a sunny day, at f/16, the shutter speed is 1/ISO These ISOs are one stop apart.

Exposure Review Sunny 16 Rule – in the shade (-2 stops) f /22 f/ 16 f /11 More Depth of Field -----> ISO 50 f/ 8 ISO 100 ISO 200 f /5. 6 ISO 400 ISO 800 f /4 ISO 1600 ISO 3200 f/ 2. 8 ISO 6400 f /2 f/ 1. 4 1/1000 1/500 1/250 Stop Action 1/125 1/60 1/30 1/15 1/8 1/4 Tripod Zone 1/2 1 At f/16, the shutter speed is 1/ISO + 2 stops 1/100 sec + 2 stops more light is 1/25 sec

Exposure Review Sunny 16 Rule – indoors (-4 stops) f /22 f/ 16 f /11 More Depth of Field -----> ISO 50 f/ 8 ISO 100 ISO 200 f /5. 6 ISO 400 ISO 800 f /4 ISO 1600 ISO 3200 f/ 2. 8 ISO 6400 f /2 f/ 1. 4 1/4000 1/2000 1/1000 1/500 Stop Action 1/250 1/125 1/60 1/30 1/15 1/8 1/4 Tripod Zone 1/2 1 At f/16, the shutter speed is 1/ISO + 4 stops 1/100 sec + 4 stops more light is 1/6 sec