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Digital Images FAQIn addition to traditional prints, you can also order copies of photographs from the Archives' holdings as digital files. Digital images can be purchased for the same price as 8"x10" prints - $17.00/image plus applicable taxes (subject to availability). Answers to some frequently asked questions are provided below to help you better understand our processes and procedures related to digital images. What do I get when I order a digital copy of a photograph from the Archives? What do I get when I order a digital copy of a photograph from the Archives?We will provide you with a CD-R containing the image formatted as an uncompressed TIFF file (Tagged Image File Format), as well as a documentation file in Rich Text format. [top] Can you e-mail me the photo?Not currently, due to technical limitations at the Archives. We hope to have a system in place to allow for direct electronic distribution of photographic images and other digital records in the near future. [top] How big is each file?Digital images provided by the Archives measure 3000 pixels along the long edge of the image.
[top] What is the source of the digital image I am getting?If the archives has several versions of an image (for example: an original negative, a copy negative, and a print) we scan whatever will provide the best quality image. Usually this will be the original negative, but in cases where we do not have an original negative, or the original negative has deteriorated, a copy negative or print may provide a better quality image [top] My publisher says I need a 300 DPI digital photo. What is the DPI of the image I will get?All digital images at the Archives were created using a scan resolution of at least 300 pixels per inch ( PPI ). However, what they probably mean is that they need a digital image that has been sized to print at 300 dots per inch ( DPI ), not that they need an image that was digitized with a scan resolution of 300 PPI. Example, if the image will appear as a 4"x5" photo on the page of a book, what they want is a digital image that measures 1200x1500 pixels. A better question to ask of your publisher is "What are the pixel dimensions that the image needs to be?" When talking about digital images, the pixel dimension is typically a more useful reference than the scan or print resolution. [top] In the previous answer, you've used two terms - PPI and DPI. What's the difference between the two?Pixels per inch are the units used to describe the resolution of an input device like a scanner, while dots per inch are a measurement of the resolution of an output device like a printer. While technically different, the terms are often used interchangeably. You can usually infer the intended meaning from the context the term is used in. A more detailed explanation appears at the end of this FAQ. [top] What resolution does the Archives scan at?It depends on the size of the object being scanned. Smaller originals need to be digitized using a much higher scanning resolution than a larger original in order to extract the same amount of detail from the image. We use a scan resolution that will allow us to create a final image measuring 3000 pixels on the long edge after processing and cropping. An 8"x10" original needs to be scanned at 400 PPI in order for us to produce a final image (after cropping) that measures 3000 pixels on the long side, while a 35mm negative needs to be scanned at a much higher resolution - 2400 PPI. Although the scanning resolution is different for each of these sources, in both cases the digital image will have approximately the same number of total pixels
[top] How large a print can I make with the digital image I get from the Archives ?The level of detail present in our scans is equivalent to the detail present in an 8"x10" print when viewed from a distance of 30cm (i.e., a print resolution of 300dpi). How good an image looks when blown up beyond this size depends on a number of factors, including the quality of the original object the scan was generated from, the type of printer being used to make the print, and the conditions under which the print will be displayed and viewed. We have used our digital images to create good quality prints of up to 20"x24" but results will vary. Many commercial photofinishing companies have information available in their stores and on their websites that gives the recommended minimum size in pixels for a digital image required to create a print of a given size. [top] Can you provide me with a more detailed scan (more than 3000 pixels along the long edge)?We do not currently provide a service where we will scan to custom specifications. Our priority is to digitize and make accessible as much of our holdings as possible. One of the ways we do this is by limiting our scanning efforts to the standards and practices we have in place. [top] Does the Archives edit the images it scans?The tonal range of some photos has been adjusted after scanning to bring out as much detail as possible. We do not correct colours or fix blemishes, except in rare cases where broken originals-glass plate negatives-have been digitally stitched together to form a complete image. [top] Can you re-size/reformat the image for me?No. We only provide digital images in the TIFF file format and at the same image size as our master image file. Any alterations to the image such as cropping, re-sizing, tonal or colour adjustments, migration to a different file format, or other editing that may be required are your responsibility. [top] What do the terms DPI, Pixel and PPI mean?DPI - Dots Per Inch. A measure of the density of ink particles a printing device applies to a page (i.e., printer resolution). DPI determines how large a print created from a digital image of a given dimension will appear when printed. Example:
Pixel - Short for picture element. The smallest discrete component of a digital image. A digital image is formed by an array of pixels that collectively form an image, similar to the way a mosaic is composed of many individual tiles. PPI - Pixels Per Inch. A measure of the image resolution an input device such as a scanner can extract from an image. The scan resolution determines how many pixels will make up the digitized image. Example:
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