Issue link: http://digital.copcomm.com/i/1010948
C A S Q U A R T E R L Y S U M M E R 2 0 1 8 25 In Fig._09, I applied 0 dB, +3 dB, +9 dB, and +14 dB of clip gain in Premiere to tracks 1-4. The top three clips translated this info accurately. The bottom clip, with 14 dB of clip gain, translated with just +12 dB of gain. KEYFRAME ONLY AND CLIP/KEYFRAME COMBINATION ADJUSTMENTS In a NLE, such as Premiere, keyframes tell the software when to apply a change. For those of us working in a DAW, such as Pro Tools, these are the equivalent of the "dots" or "breakpoints" you see in the volume display when writing automation. Picture editors can apply key- frame automation in addition to clip gain—much like we can on the audio side. For the following, refer to Fig._10 which shows volume and clip gain info. All four tracks had the same volume (keyframe) automation in Premiere with my maximum volume (keyframe) level adjustment being +3.5 dB. The track with only keyframe adjustments (top blue track) translated fine—as there is a +12 dB volume limit in Premiere. Rides were at the same level and position as in the sequence. I applied a global 3 dB of clip gain across the clips on the green track (which, again, also has the same volume rides as track one) and the translation was interesting. The clips that did not have any keyframe automation (the first two small clips that aren't zoomed in on) came across with 3 dB of clip gain. Once volume automation was introduced on a clip, the clip gain value changed to zero (unity), but the dB value of the clip gain (+3 dB in this case) was added to the volume reading. For instance, a volume ride of 3.5 dB on a clip that also had 3 dB of clip gain in Premiere translated as a volume ride of 6.5 dB with zero (unity) clip gain. The same total dB level but gain staged differently. Fig._10: AAF clip and volume translation results Wanting to see what happened if the total dB value (clip + automation) exceeded 12 dB, I applied 9 dB of clip gain across the clips on the purple track. Remember, my max volume automation level was +3.5 dB for all of these tests. Things stayed consistent until the +3.5 dB keyframe—yielding a max volume level of +12 dB— though it would output +12.5 dB in Premiere. After that, for all the keyframes that were +3 dB or lower, automation translated accurately by adding 9 dB of gain to the original volume automation. I then did the same thing but with a total of 14 dB of clip gain to track four. Levels were largely skewed and were frequently capped at +12 dB as the total volume often exceeded the assumed 12 dB max gain (even on the two short clips at the beginning). My takeaway from this is that there is a 12 dB total maxi- mum amount of boost that can be applied to a clip if you want it to translate accurately. If retaining the levels heard in the edit suite is a priority, you'll want to make the picture editor aware of this limitation—though they may not always want to do dB math while editing! CONCLUSION… While inquiries were made to Adobe in hopes of finding solutions, no responses have yet to be received and a search of online forums serving the software yielded no solutions to these issues. In the meantime, as more and more projects edit in Premiere, we may need to create workarounds and unique workflows, as well as pick and choose what information is most important for us to efficiently complete our projects in audio post. SUGGESTED ADDITIONAL READING… April Tucker CAS discusses "Common Audio Issues with Premiere" on her blog at: www.ProAudioGirl.com (This particular blog is easily accessible on the home page under "Featured Posts"). April discusses a couple issues, along with solutions for some problems, including distorted/ garbage audio when exporting embedded AAFs; corrupt/ missing tracks if the sequence contains nested clips; inability to export with transition effects; and pointing to multi-channel audio files when linking to source media. It's definitely worth the read.•