RAW vs. JPEG/Camera RAW

What is a JPEG?

JPEG is a common image file format often used in digital photography. The acronym JPEG is short for Joint Photographic Experts Group - the group responsible for its creation. These digital image files use “lossy compression”, which is a method of shrinking a file for storage. Lossy Compression is an irreversible and inexact form of compression because the file is smaller when re-opened than it was originally. JPEGs however can be adjusted for their image quality to storage size ratio. This ability to decide the relationship between storage size and image quality is part of why JPEGs are so common. However, it is important to remember that no matter how high of image quality you set a JPEG at, there will always be some amount of data loss. Data loss from JPEG compression occurs each time the file is saved and re-opened

What is a RAW file?

Many file extensions can fall under the category of a RAW file format. RAW files are not fully rasterized files, that is to say they are not ready to be edited in a computer program or printed. The advantage of this format is that the greatest quantity of data is available and the RAW format is not only “lossless” but can be converted to many other lossless formats. Lossless compression utilizes algorithms that allow the data to be exactly reconstructed as before so that no image quality is lost.

What are the advantages of each?

JPEG

1. you have a much better shot at downloading and immediately being able to use the photo, versus in camera raw it is going to flatten the photo and lack a contrast, meaning you will need to edit it before it looks like a final version of your photo.

2. less information is stored on each photo so they take up much less room of your memory

3. Great for quick use, slideshows that you want to have done for a presentation are going to much quicker in JPEG format

4. Online use: RAW photos are simply going to take too much time to download!

5. Taking a lot of photos in a short amount of time.  Although it may seem like seconds pass quickly in every day life, waiting that extra second and a Hal can be extremely irritating when you are trying to capture a lot of photographs quickly

RAW

1. this version of the photo has ALL the data from the camera at the time the photo was taken, this allows you to go back and edit the photo more comprehensively than a JPEG will allow

2. much larger "Dynamic Range" ("Dynamic Range is simply the amount of tonal range detail from the darkest shadows to the brightest highlights. Dynamic Range detail in JPEG files is significantly reduced as compared to RAW."-SLR Lounge)

3. great for shooting journalistic styles of photography, meaning the light and exposure is constantly changing.  Even the best photographer does not want to have to continuously being adjusting their settings for every photo, shooting RAW allows you to take the photo now, then go back and fix it later.

4. Great for landscapes, lots of tonal changes

5. Details are much more defined when you go back to edit later on, especially in faces

How do you open a RAW file in CameraRAW, make basic edits, and convert to another format for print or web?

Assuming you are using a computer that already has photoshop downloaded onto it, when you click on a photo taken RAW to edit it, it should automatically open up two windows.  The one set back on the screen is photoshop, the one pressed more to the foreground of the screen will be the CameraRAW edit feature.  There you can make edits such as exposure, radial changes, white balance editing, saturation distortion and more.  If at any time you feel you have push the photo in a direction you do not like, feel free to "Step Backward" in the the tabbed menus and it will undo the most recent edit.  On the right side of the cameraRAW screen there will be a column of editing tools that you have been working from.  You can always take it back to "As Shot" as a more efficient way to remove all edits to the photo and start over fresh.


When you are happy with the edits you have made to that original file, hit "save changes" at the bottom right hand corner of the screen and it will automatically import your new and improved photo into the photoshop window.  It will become the first tab of many files that you can have open in the photoshop window.  If you open another photo in cameraRAW, it will simply hold the original photo's place in the tab and wait for you to save the changes to your new file, and that will subsequently become the second tab.

At this point there are some other editing options available to you in photoshop, such as: cropping, mirroring, changing the image size, changing the canvas size (if you are going to merge files/photos), etc.  Feel free to make changes you would like before you are going to save and print.

Once all the changes have been made, go up to the top of the window and click on the tab that says image>image size.  Set your image to whatever size will be the final printing size and make sure the resolution is at at least 300 dpi and the quality is set to 12.  There are instances you would use smaller setters, but not typically in printing.  Save your image, typically once as a .psd that you could go back and further edit, and a second one as a .jpeg to print. 
Then you are ready to go!

All About White Balance

 One way of manipulating the photos you take, that is not often utilized to its full extent is that of white balance. While we generally simply allow the camera to do its own thing in regards to white balance, there are significant advantages to understand white balance and learning how to manipulate it.
The first step taking more control of your photos is understanding what white balance is: the process wherein the camera adjusts the shades of the whites that appear in the photograph taken, so that they match or differ from the shades of white in the subject of the photo. This requires the camera or photographer to recognize ranges in color temperatures in the subject in order to match or differ from the specific shades of white. By measuring the "color temperature" (measured in kelvin) the camera attempts to match the shades of white in the photograph taken to match the temperature of the "true whites" in the subject.


The next step in the process is understanding the different settings of white balance. Typically, white balance can be set under your camera's manual exposure menu settings. Under the white balance menu, you can choose one of several options to set your white balance. Common settings (layman's terms for specific color temperature measurements) are, "Auto White Balance", "Daylight", "Shade", "Cloudy", "Tungsten", "White Fluorescent", "Flash", and "Custom". Keep in mind different makes and models of cameras may have different settings. Each of these options, except for Auto and Custom, are controlled light temperatures that are set according to average temperatures of various light sources in order to correct an image for natural-looking light. When set to auto, the camera will automatically change the white balance what its programming thinks it should be based on what is being viewed through the lens. When set to Custom, the camera will adopt the white balance from an image that you specify on your memory card.


Next, choosing how to set your white balance. There are multiple ways to adjust the white balance in your photos. One of those is through the automatic feature on the camera. This method has several pros and cons.  There are several positives of using the automatic setting. DSLR cameras are pretty advanced now, and especially if you are a novice to photography the camera may be able to adjust the whites in your photos better than you can. If the light is changing over your photo taking session the camera can automatically adjust for that, allowing you to just focus on your subject(s). However there are cons. Although the auto feature is very smart, it is not completely intuitive concerning color temperature. While you may be taking a picture in warm light, the camera may adjust the whites to have a much cooler feel. Hindering your desired effect. You may want to change the whites to be cooler than they really are, however on automatic you have no way to do that. Automatic also does not create automatic completely accurate color balance of the photo being taken. So if you want total and complete control over your photographs colors, you may want to think about using manual white balance.





The biggest advantage to manually setting your white balance is the consistence across all photographs you take with that specified white balance. No matter what your light source is, the camera will take the photograph with that one white balance. This is useful when you are taking multiple photographs of the same thing—instead of minutely trying to adjust the white balance to the same light temperature in post-processing, the white balance is already uniform. However, manual white balance can also be problematic. Forgetting to change the white balance before shooting a different photograph under different lighting conditions can lead your image to be irreparably washed out at worst, or too blue or too yellow/orange at best. Misinterpreting what kind of light you are shooting with can also lead to this problem. If you choose to shoot with manually adjusted white balance, take care to be aware of what the white balance is set to.

Here is an example of white balance gone wrong:

photo by Mykaela Rogers

The cause of the problem in this photo stemmed from forgetting to check the manually set white balance to make sure it was set correctly. The white balance was set on Tungsten, which caused the camera to interpret the scene incorrectly, because the scene (a sunrise) is not lit by a Tungsten lightbulb. This washed out the image data and made what is still viewable too blue.

The same image after post-processing:

photo by Mykaela Rogers

Even after attempting to fix the image during post-processing, the light was so badly clipped that the raw image data didn't contain most of the color or clouds in the sky. Post-processing was able to restore some of the image data, but not enough to salvage a decent photograph.

All About Sensitivity and ISO

All About Sensitivity and ISO

ISO is a very important setting on your camera that highly affects image quality. ISO stands for International Standards Organization, and it is a standardized scale for measuring sensitivity to light. When taking a picture, your ISO setting is used to determine how sensitive your camera is to light. It is one of the 3 settings you need to understand in order to take a quality photograph manually. ISO adjusts the sensitivity of the digital image sensor inside your DSLR camera. The responsibility of the image sensor is to gather light and transform it into an image.

It is important to understand that the LOWER the ISO number (100, 200, 400), the less sensitive your camera is to light, and the HIGHER the ISO number (1600, 3200), the more sensitive it is to light. The ISO setting you decide to use will depend on the amount of light in the setting you are taking pictures in. Therefore, if you want to take a photograph indoors or at night when the light is dim, you must set your ISO higher in order to produce an image. And vice versa, when taking a photo outdoors in daylight or in other bright scenarios, ISO needs to be lower in order to produce an image. In other words, the more light you are working with, the lower you can set your ISO.

However, you must know the risks that come with a higher ISO setting. Increasing the ISO, while often necessary in cases of low light, or fast shutter speed, comes with certain setbacks. As you raise the ISO, more light registers on the camera’s digital sensor. The more easily light is registered on the sensor, the more likely the light coming in is to distort, which can lead to grainy images, and skewed coloration. For this reason, you typically want to keep ISO as low as possible. To produce clear images, photographers will set their cameras to a typical ISO based off of the light in the setting and adjust the shutter speed and aperture however they prefer. Bottom line, there is a specific ISO that will always be best for specific settings and it is important for a photographer to understand how to use it.

High ISO:

Notice that the image has a lot of noise, with occasional colored pixels in the black sections. However, this image was shot at night, with low light. Increasing the ISO may have been the only way to achieve proper exposure. And the result is not altogether undesirable, depending on the artist’s preferred aesthetics.

Low ISO example:

This image was shot outdoors in bright daylight. The photographer therefore had no problem shooting a properly exposed photograph with very low ISO. The low ISO means that the image comes out very clean, with absolutely no graininess.

Varying ISO example:


This image was shot with four different ISO settings and then composited to show the differences as ISO changes. At 100 ISO (typically the lowest setting) the image is crisp and devoid of grain. The image is progressively less sharp as the ISO moves up. At 3200, the image is grainy with slightly muddled colors.

All About Aperture

Thomas Atfather Good- TAG_Pentacon_50mm_Comparison_Front-11/17/2012- Sourced from flicker

Aperture

Aperture like the pupil in the human eye is the hole in the lens which allows light to pass into the camera. Through increasing or decreasing the size of the aperture will either allow more light or less light into the photograph. Through manipulation of the aperture you are able to control the exposure of your photograph by the amount of light that enters the lens; and also allows the photographer to alter distance of the space in the photo that is in focus.   

There is no “normal aperture value”, but rather normality is dictated by your shooting choice, subject, etc. a list of the typical full stop aperture f stops includes: f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22 (and f/32, f/45, f/64 depending the lens you use) with every other F/stop being a numeric double of halving or the other F/stops. 

However, when shooting portraiture or close up photography, it is most desired to isolate the subject from the background, making the person or thing the subject of the photograph. In this situation, you would use a large aperture (F2.8) to create the shallow depth of field. In a landscape, you would do the opposite in order to achieve as much detail as possible, using a higher F/stop such as F8 (or F11).

 Portraiture

 Landscape

Wide aperture vs Narrow aperture
Wide Aperture or a large aperture can be used to bring only the foreground of a photo into focus while blurring the background within a short focus distance.

Manuela Hoffmann photograph 06/28/2010  F/2.8 sourced from flicker

A narrow or small aperture will bring both the foreground and the background into focus within the a longer focus distance.  

Marcus Peaston- Day 213 Banner Hill- 08/01/2013, F/16. Sourced from flicker

Aperture plays a factor in controlling the depth of field with focal length. As the F/stop is increased, with a smaller opening in the lens, light becomes more concentrated, allowing a larger depth of field. Objects in the foreground and the background are both crisp and visible clearly. When your F/stop is decreased, the aperture in your lens becomes larger, bringing your area of focus in closer to the camera, making the background blurry and indistinct. 

For example when everything else about the focal length is the same. When you have a 100mm Lens set at an F/stop of F/2.8, you will have a shallow depth of field of what will be in focus. While if you had a 50mm lens also set to F/2.8 with the same distance you will have an increased depth of  field than what you would  have if you tried to focus on a subject within 3ft of the camera.

This is because your focal length can adjust the camera’s and photographer’s field of view within a photograph. With a long lens (such as a 200mm) your field of view is tightened, making it a small angle shot while increasing the length at which the camera can capture detail. This in turn limits your ability to shoot at a decreased F/stop, because the lens physically begins to act like an aperture, decreasing the amount of light that can access the sensor, making it harder to isolate objects to achieve a more blurry background or foreground for a singular object. In the case of a wide angle lens, the smaller focal length, such as a 24mm, allows your camera to open to a wide angle and can focus in on objects close to the camera. You then have an ability to decrease F/stop to isolate subjects.

Narrow Aperture with long focal distance

Wide Aperture short focal distance

Image sharpness and resolution

A wide aperture such as F/1.4 has a larger diameter of the hole in the optics vs a narrow aperture such as F/20 which has a very narrow diameter of the optics. This results in a shallower depth of field is due to a decreased optical resolution and can also cause the image to be less sharp in quality due to an increased Chromatic Aberration which is one of the most common focus failures that causes and unclear photo due to colored fringes.

A narrow aperture such a F/16 or higher brings whatever is in the focal distance of the lens into focus whether it be foreground or background. This is caused by an increased optical resolution that provides a deeper depth of field from the same focal distance but a higher image resolution and image sharpness when compared to a wide aperture.  

However when the F/stop is at F/22 or higher it can also cause the optical resolution and sharpness of the image to fall due to light diffraction. This in because the sharpness of a quality image is actually a separate operation of the camera than the depth of field. The larger the F/stop the more of the Chromatic Aberration is eliminated, or rather the more the lens is able to focus the colors from the different wave lengths of light which factors on in the clarity of the image. A high F/stop can cause the existing light waves that enter the camera to fracture, this reduces the quality of the image from the sharpness and the resolution. While the wider the aperture is will Increase the Chromatic Aberration that causes the the resolution and sharpness of the image to drop. 

Diffraction, Aperture, And Starburst Effects - Pye Jirsa- 2/8/2011
Sourced from SLR lounge

Visual Examples 

 (varying focal length in correlation with magnification and field of view)

(depth of field)

Image sources

Good :https://www.flickr.com/photos/thomasgood/8195153977/in/album-72157631677767296/

Hoffmann: https://www.flickr.com/photos/pixelgraphix/albums/72157624382746786

Peaston : https://www.flickr.com/photos/kelmon/9416177411/in/album-72157632403824116/

Horse depth of field: http://www.nikonusa.com/en/learn-and-explore/a/tips-and-techniques/understanding-maximum-aperture.html

varying focal length: http://www.nikonusa.com/en/learn-and-explore/a/tips-and-techniques/understanding-focal-length.html

https://www.slrlounge.com/diffraction-aperture-and-starburst-effects/