These tips are for the beginner; our intent is to keep it simple and clearwe welcome feedback. We’ll start with the mechanics and then address the crucial topic of lighting. The focus is on photographing 2-D art with some additional comments relevant to 3-D art.
When photographing images to be viewed online, the goal is to produce an image that will fill the viewer’s browser window. For most current monitors, a dimension of 2000 pixels on the longest side is sufficient, and 3000 pixels would be ample even for large, high resolution monitors. Fewer pixels produce a smaller display imagea disadvantage when the viewer is a juror. An image in excess of the browser’s pixel dimensions will be reduced to match the browser’s window for display. Thus, anything in excess of 3000 pixels on the longest side is not useful.
NOTE: This may be a good place to point out that, although Megapixel means a million pixels, due to the binary way computers compute it’s really 1,048,576 pixels. (Same thing with Megabytes.)
A 3.1 Megapixel digital camera produces JPEGs with pixel dimensions of about 2048 x 1536 pixels and would be adequate to photograph your artwork. Cameras with more Megapixels will produce larger pixel dimensions, which provides useful flexibility when cropping is needed. What happens with too many megapixels is discussed in the section Preparing the Images for Display.
Locate the camera at a place opposite the midpoint of the artwork on a line perpendicular to the work’s surface. Turn off any on-camera flash. Use a tripod, if possible, or brace the camera to avoid movement. Avoid wide angle lenses. Orient the camera so the long dimension of its image matches the long dimension of the artwork. Adjust the distance and/or telephoto to capture the entire artwork with minimal background. If the art will be presented in a frame, include the frame in the image. Eliminate any distracting background; it may be necessary to use a plain backdrop or to crop the image later to achieve this.
When photographing 3-D art, more than one view will likely be needed to show the nature of the artwork. Easy Entry Online allows two images for each artwork but, if more views are necessary, two photographs can be combined in a single image. The artist will need to experiment with different views and various lighting angles to find the best combination for the individual piece. Because of this, the next section is applicable primarily to 2-D artwork.
The goal is to use a white light that accurately captures the colors in your artwork and a setup that produces minimal or no shadows. The problem is that “white” light is largely an abstraction. All light has color with some sources emphasizing the yellow-orange-red part of the spectrum and others emphasizing the green-blue part. What we see as white is the best balance of the spectrum colors for our viewing conditions. (Under the red night lights on board ship, the red stripes on my uniform looked very white to me.)
The best natural lighting will normally be a bright overcast day. Direct sunlight is fine but almost impossible to arrange without glare or shadows. On a sunlit day, have your artwork face a white wall exposed to direct sunlight. If surface texture is an important element, you may want to move or angle your work to select the best lighting effect. Light reflected from a colored surface will result in color shifts, as will light from a clear blue sky, e.g., by placing the artwork in the shade on a sunny day. This should be avoided, if possible, but will be mitigated if your camera has an automatic white balance control, which should be turned on for all artwork photographs. This usually means exposing the camera to a white sheet of paper under the existing lighting conditions to set the white balance for your setup.
If photographing indoors with artificial light, at least two lamps should be placed at the same height as the camera but offset to the side so they are about 45 degrees from the perpendicular. Changing the distance or angle of one of the lamps may assist in emphasizing surface texture, if needed. You should look for lamps that mimic daylight. The best indication of a lamp’s spectrum is its Kelvin temperature, which might be printed on the package. 5000 K mimics sunlight and lamps between 4000 K and 6000 K would be acceptable. Instead of the Kelvin temperature, or in addition, appropriate lamps might be marked Daylight or Natural White. Avoid Cool White and Warm White because they will shift colors toward blue or orange, respectively. Using directional shades on the lamps will avoid reflecting light from strongly colored elements in the room.
After you have an image that you believe accurately represents your artwork, there are two remaining things to consider: background distraction and pixel dimensions.
Background distraction can be a problem if the artwork does not fill the image space and the background competes for attention. A plain gray wall would not distract but a flowered drapery would. In any case, eliminating the background has the virtue of emphasizing the shape of the artwork. There are various free image editors (see next section) that allow cropping to eliminate background. Learning to use them is straightforward and well worth the time spent. Always operate on a copy of the original image in case things go sideways.
The pixel dimensions of your original image can be determined either from your camera instruction book or by opening the copy of your image in an image editor. However, if you crop the image to eliminate background, it is the pixel width and height of the cropped image that you need, which you can get from the image editor after cropping. Multiply the width times the height to get the total number of pixels. The reason for getting these three numbers is explained in the next paragraph.
Easy Entry’s application will not process images greater than 20 megapixels or files greater than 2 MB (megabytes). A high quality JPEG image of less than 20 megapixels will rarely exceed 2 MB in file size. If either of these limits is exceeded, an image editor can be used, first to crop the background away, next to limit the pixel dimensions to 2000 - 3000 pixels in the longest dimension, and finally saving it with a level of JPEG compression (try “high” quality first) that provides a file of less than 2 MB. Try to do all of these in one editing session because repeatedly re-saving a JPEG will degrade the imageanother good reason for operating only on a copy of the original.
Reducing the pixel dimensions to 2000 or 3000 pixels on the longest side will result in shorter upload and processing times, but if you don’t have access to an image editor, go ahead and enter the image you have. If it exceeds 20 megapixels or is a file exceeding 2 MB, Easy Entry will reject it with an immediate message telling you why.
Pixlr is a free, user friendly, online photo editor that will allow you to crop and resize your images among many other capabilities. Select image in Pixlr’s top menu and then select either the image size or crop tool.
Basic image editors that allow cropping and resizing are included with Mac OS (iPhoto) and Windows (Photo or Paint). Oddly, iPhoto provides re-sizing only through the crop function even if no cropping is done.
Unless you are a photographer, the image editors mentioned above should fill your needs. However, searching the web will turn up many other online and download editors, some free and others at low cost. Searching the web is also a good way to get answers to your “how do I” questions. Just look at several answers before deciding on the best one because they can vary widely in clarity.
When editing for display on the web, ignore the pixels per inch (ppi) setting as that will not affect online display. It is an instruction for printers only that controls the quality and physical size of the printed image. For more on that, or if you are curious about why resolution is expressed differently for cameras, monitors and printers and how the different expressions are related, take a look at Easy Entry’s notes on resolution.