Test Chart Substrate and Sizing Guide
This guide enumerates the possibilities and constraints of our test charts and provides resolution (MTF) information for the different options. Imatest has introduced Chart MTF Compensation, which can as much as double the resolution suitability of a given test chart.
Inkjet
Inkjet is the lowest resolution process we offer, but also the least expensive and most versatile. The minimum print size with inkjet is approximately 8” x 10”, and the maximum print size for a single sheet is 44” x 80”.
Inkjet charts are available in three different substrates: Matte and Semigloss for reflective testing and DisplayTrans for transmissive tests using a backlight. All inkjet options are roughly the same resolution.
Inkjet is best suited for cameras tested at a moderate distance in order to compensate for the low resolution of the print. It is also suitable for low-resolution or wide-angle systems. As the resolution of the target is relatively low, the size of the chart needs to be larger to accommodate a higher resolution sensor.
We can produce custom charts, and custom sizes of most of our standard charts. Contact charts@imatest.com with your requested size and information about your lens (field of view and testing distance) and sensor (pixel count and aspect ratio.) We need the pixel count to confirm the size you are requesting will be adequate for your imaging system. Our Chart Finder Tool can help you determine the size of your imaging plane at a specific testing distance.
Black and White Photographic Paper (Silver Halide)
Photographic media offers high-resolution reflective prints when a transmissive target is not an option. These prints are over twice the resolution of inkjet media.
The minimum size of a photographic print is approximately 8” x 10” and the maximum size is approximately 40” x 50”.
Our standard photographic targets include our eSFR ISO chart (3 sizes) and a multi-size option of our SFRplus chart. This multi-size is best suited for testing low-resolution systems at close distances. We can offer custom charts on this media for an additional fee. Contact charts@imatest.com for information.
Transmissive Photographic Film
Our Color and Black & White film targets are printed using high-precision LVT Technology. These transmissive targets require a lightbox in order to be used properly.
Black and White
Black and White film is over twice the resolution of our inkjet targets, and can optionally include a color patch for color measurements. The size of the film is 8″ x 10″ or 12” x 20” (with ½” on each side as unprintable area). The minimum target size on this media is roughly 2” x 3”. We can print multiple targets on a single sheet of film depending on the size and resolution requirements to help make this option more cost-effective.
This media is suited for customers testing in a small area with low to medium resolution cameras.
Color
Our high-precision color film targets are printed on 8” x 10” film with a maximum printed area of 9.25” x 7.75”. The minimum target size on this media is approximately 0.5” x 1”. As with the Black and White film, we can print multiple targets to a single sheet of film to make this a more cost-effective option.
This media is suited for customers requiring a very compact testing system or those using conversion optics to simulate infinity within a very small space. The fine detail of the film allows us to test mid to high-resolution cameras at close distances and with a small field of view. Color film has the highest dynamic range of all of the targets we offer.
Chrome on Glass Photomask
Chrome Photomasks are our sharpest option for resolution testing. We use a lithographic photomasking process to print chrome directly onto glass. This process is single tone, so there is no gray-scale or tonal variance.
Chrome on Glass offers superior resolution when color and tonal measurements are not needed. We can make targets as small as 2mm x 3mm for measuring devices such as endoscopes or microscopy equipment. When printing to glass, the chrome has an optical density of 1, which gives a contrast ratio of approximately 10:1, suitable for resolution measurement.
Our standard glass plates are 4” x 4” with a non-printable border of 1 cm. We can source plates up to 20” x 20” and as small as 1” x 1”. Any plates larger than 4” x 4” require an extended lead time of 6-8 weeks.
We can customize the size of various targets such as our SFRplus or ISO-eSFR targets on request. We can also print most custom design requests to glass, though some may require an engineering fee depending on the complexity of the design. Contact charts@imatest.com.
Test chart suitability
Detailed information on test chart suitability — relating camera resolution to chart size — can be found on Test chart suitability for MTF Measurements.
General information on sharpness, MTF, and the wide range of available charts can be found in the Sharpness section of the Imatest Documentation page.