We are pleased to announce our new High Dynamic Range (HDR) test chart with a density range exceeding 120dB (optical density >6.0). This chart allows you to the measure the dynamic range, tonal response and noise of HDR cameras with a single image instead of multiple, exposure bracketed images. It also contains slanted edges for MTF measurements. The middle gray background density closely resembles our 36-patch Dynamic Range target, enabling proper exposure with automatic exposure cameras. HDR test targets with black backgrounds tend to overexpose the brighter patches with auto-exposure cameras.
The new chart is well suited for measuring both camera and sensor dynamic range, which are fundamentally different. Camera DR measurements are affected by flare (stray) light in the lens. They represent real-world performance. Sensor measurements are based on the patch pixel and noise levels in unprocessed RAW images, using the technique described in Multicharts/Multitest/eSFR ISO Noise, which fits data to an equation based on dark and photon noise.
The HDR chart’s active area of 197 x 235mm is a good fit for both the DNP Standard Color Viewer and ITI LED lightbox. Imatest recommends using the HDR Target with a high illuminance light source in order to provide sufficient light to test image sensors over their range of sensitivity.
Visit our store to learn more.
ITI LED Lightbox
The ITI LED Lightbox produces uniform light with excellent spectral characteristics that can be adjusted over a wide range of brightness (30-10,000 lux; >300:1) to illuminate transmissive test charts. Automatic control is available through Bluetooth support or USB. The 260 mm x 220 mm viewing area is an excellent match to Imatest’s 36-patch Standard and High Dynamic Range charts.
This lightbox provides 95% uniformity, adjustability, and a high color rendering index (CRI), making it superior to other LED or fluorescent systems we’ve seen. See our Lightbox Comparison Guide for details or learn more from our store.
