Sony a7 shuttercount4/25/2023 We start to expose the camera at 1/25s shutter speed at T1.5 and adjust the studio light such that the forehead of my colleague Johnnie is at the cusp of clipping. For our latitude test we have a standard setup with fixed studio lights and a fixed distance between subject and lights, and subject and rear wall. Latitude is the capability of a camera to retain colors and detail when over or underexposed. This is also confirmed by the latitude tests below. Hence, the Sony a7 IV has in total about 3 stops less dynamic range than the ARRI ALEXA LF. Those would be accessible by using noise reduction in post with the ARRI camera. If you compare that with our benchmark for dynamic range, the ARRI ALEXA LF (lab test here) you can see in the very same IMATEST graph above the blue “14.7” line (14.7 stops for SNR = 1) some additional 3 stops. ![]() If you look at the IMATEST result, in the middle graph above the blue SNR = 1 line designated with “14” you can see about 1 additional stop before the signal differentiation is gone. I’m impressed! Those are really good results from the Sony a7 IV! Just keep in mind, much of it is achieved by downsampling and significant noise reduction in camera which cannot be turned off. Image credit: CineDīy the way, a very similar result is obtained from the Sony A1 if the 3840×2160 full-frame mode is selected – also here the sensor is properly downsampled. Sony a7 IV- IMATEST Dynamic Range result. Looking at the waveform of our Xyla 21 stepchart, we see about 13 stops above the noise floor: Sony claims on its webpage that the camera downsamples UHD from the full 7K sensor – hence the image should show rather good dynamic range results as downscaling reduces noise hence improving the signal-to-noise ratio (SNR). The Sony a7 IV features a 33-megapixel sensor, but only allows video recording at 3840×2160 UHD full-frame mode as the maximum resolution and that’s where Dynamic Range results get interesting. If you are interested in our procedure and learning how we test dynamic range, please head over here. ![]() Sony a7 IV – Dynamic Range at ISO800, SGamut.Cine/SLog3 In APS-C crop mode, the rolling shutter in UHD becomes quite a bit better at 13ms. Only the Canon EOS R6 is worse with 30.6ms (lab test here). with the Panasonic LUMIX S1 and LUMIX S5 around 22ms (lab tests here and here) or the Canon EOS R5 at 15.5ms (17:9, lab test here). Ouch – this is a rather high value (lower values are better)! For comparison, the Sony A1 in 8K full-frame mode shows 16.6ms, the Sony a7S III only 8.7ms (Lab tests here and here)! Also, the competition fares better e.g. Sony a7 IV, full-frame mode, rolling shutter measurement.
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |