Export TIFF

TIFF - Export

Tag Image File Format (TIFF) is perhaps the most versatile bitmap format. It is used for data storage and interchange. It can be viewed on almost any computer or by any computer application. The parameters found at the bottom of the Export Panel (shown above) are used to export TIFF files.

The Dots Per Inch (DPI) parameter is used to define the resolution or quality of the exported representation. Normal display screen viewing requires about 72 DPI for acceptable visual quality. Printed applications usually require 300 DPI for good quality representation. High quality printed results may need 600 DPI or greater.

The size of an uncompressed TIFF bitmap depends directly on the imaged area, with color depth as a third dimension. It grows rapidly (square law) as the DPI is increased. 2400 DPI may be prohibitively large even for small drawings. The practical limit for an 8 inch by 8 inch drawing is 1600 dpi, there are limits internal to macOS that limit an off screen bitmap to 16,000 pixels by 16,000 pixels.

Keep in mind that we cannot regenerate an EazyDraw vector representation from a TIFF export file. If your final work needs to be TIFF (or any other bitmap format) be sure to save and archive the EazyDraw original in case modifications to the work are needed in the future. You can always generate a revised TIFF export from the original-but the reverse is not possible.

The Content popup menu provides a selection to specify the elements of the drawing that are included in the export. The choices are self explanatory.

The Background popup menu further defines what is included in the export. It is often desirable to define the backdrop of the drawing differently for an export, compared to the screen display. For example a reference grid might be used for the screen display but would not be included with the export. This setting determines if the exported graphic will be transparent or have a solid (white or colored) background.

Use the right most popup menu to chose a background option. You may choose no background, white or black and whether to include the Grid in the output.

Dual Representation is of primary interest to Mac macOS software developers and icon designers designing for high resolution retina display. This was Apple’s definition to support higher resolution displays. This is no longer the method that should be used for high resolution support. The parameter remains available and may be of use for supporting high resolution graphics on other platforms. In one TIFF file two images are saved, one a normal 72 dpi image the other a 144 dpi representation. Tiff files in this format are termed "Dual Representation". EazyDraw generates these files when the checkbox is selected. The high def, 144 dpi, image is generated automatically from your vector image.

Use the save button to execute the save action after all parameter selections are made.

Use the "Add Thumbnail Preview" button to install a custom icon for the exported file. The custom icon will be a small image of the exported drawing or graphics. If this button is not checked the macOS Finder will install an icon in accordance with the system settings and applications available on your system.

Use the "Color Space" popup to select a particular pixel format for the destination bitmap. RGBA, which is Red-Green-Blue colors with Alpha channel (alpha channel provides support for transparency) is the most common choice for the PNG format. The other formats will use correspondingly fewer bytes for each pixel and will result in smaller file size. The mask formats are sometimes used by other applications when constructing icons, but not so much in recent years. CMYK (Cyan, Magenta, Yellow, Black) is commonly used to prepare artwork for printer-publishers such as a magazine ad. Normally you will want to have this selection agree with the setting on the Layers Inspector, the Color Space topic is discussed in more detail on the Layers - Color Space help page.

Proper selection of the correct export parameters depends on the ultimate use of the exported file. It is usually best to determine settings by experimenting, possibly with small test files.

EazyDraw uses vectors to define all graphics. A vector representation does not need to record each dot along a curve. For example only 4 dots are needed for a full Bezier curve segment. The size of a vector representation is driven by the amount of content, not size and detail. A small icon containing numerous curves, colors and shading can result in a very large vector based representation. The TIFF representation of this example would require only a small file at 72 DPI. These are the trade-offs that are important, especially if the work product is intended for communication over networks or the internet.

With no compression a bitmap file’s size does not depend on content, a 5 page blank document (with a border) is the same size as a 5 page brochure packed with curves, special effects, and text. If the bitmap is visually sparse, compression may provide significant file size reduction. If the bitmap is rich in detail, colors, and shades loss less compression may not significantly reduce the size.

The compressions presented here are loss-less, they do not degrade or remove information from the bitmap. However, that doesn't mean the full quality of the vector derived original is preserved-just the quality of the defined bitmap. The JPG format provides lossy compression of TIFF bitmaps.

You may generally be certain that any recipient will be able to view TIFF graphics. If the recipient is using Mac OSX they may download the EazyDraw reader to view and interact with your original work in the native EazyDraw vector form.

The Antialias check box selects the use of macOS’s antialiasing algorithms during preparation of the image. In some cases it may be best not to use this capability. If antialiasing is used when viewing the image, it would be applied twice. If you need exact control over the color of each pixel be sure to turn off antialiasing as it will modify individual pixel color on color contrast borders.

Interpolation is applied to Bezier paths during preparation of the image. This normally has little affect on the image. If exact control over placement of pixels of lines and curves is needed select no interpolation. There are 3 levels and an automatic selection.

When designing graphics with a transparent background it can be confusing if included graphic elements have a solid white (non-transparent) background. In these situations designers will often set a distinct background (like the "green screen" in television production) color for the drawing. This is set on the Page Layout panel. Then when exporting to produce the product graphic, choose "No Background" for the Background setting on this panel.