I have included some small adds in the manual that deal with HDR. See if they fit. There would also be to change the Blend Algebra examples file written by Georgy. [Part to append to the file https://cinelerra-gg.org/download/testing/BlendPluginExamples/Examples.txt]: Example 6. ---------- To tonemapping an HDR media and report its values within the range (0, 1.0): BLEND_PROGRAM_INIT COLORSPACE_RGB PARALLEL_SAFE BLEND_PROGRAM_PROC float mult; mult = KEY_A-0.5; if (mult >= 0) mult = 1+mult*10; else mult = 1/(1-mult*10); R(0) = R(0)*mult; G(0) = G(0)*mult; B(0) = B(0)*mult; BLEND_PROGRAM_END First attach this blend program to your track above the other plugin which you want to make not to clip. Switch clipping off in the blend program dialog. This blend program will use the alpha slider (which can have the value between 0.0 and 1.0) in the following manner: 0.5 (exactly in the middle): no RGB change 0.6: R,G,B are multiplied by 2 0.7: multiplied by 3 ... 1.0: multiplied by 6 0.4: multiplied by 1/2 (i.e. divided by 2) 0.3: multiplied by 1/3 ... 0.0: multiplied by 1/6 (divided by 6) If you set it, for example, to 0.4 here, your R,G,B values will be divided by 2, so that the color values up to 2.0 will be scaled down into the clip range. If you can have values up to, let's say, 5.0, then set the alpha slider to 0.1 to scale down by 5, etc. Then attach the plugin you need to work unclipped, your histogram or whatever. Pay attention that all the color values your plugin gets now, are scaled down uniformly. Then attach the same blend program once more, under your needed plugin. This time set the alpha slider to 0.6 (if it is 0.4 in the upper one), or to 0.9 (if the upper one is 0.1), i.e. displace it from the middle in the opposite direction. The unclipped values coming from your working plugin will be scaled back by the same amount.