Murrayatuptown
lvl.1
United States
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Question/Suggestion:
Short version:
The ability to select microphone processing 'flavors' for ALC, compression, etc. would make the camera even better. There are some difficult (ambient noise) recording environments that produce unusable live audio capture (loud music concert with noisy patrons) because of the powerful/aggressive audio processing the OP3 performs. I don't personally know what the OP3 firmware does, but I can qualitatively describe what happens to the audio).
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Detailed long version follows: (Thanks for reading!)
I record live music for some musicians, sometimes in noisy environments. This is a bit verbose because I have made some observations and made some changes with my mic'ing to interpret my results and identify my problems.
My microphone methods evolved and reveal some detail of what I think would benefit from a feature enhancement
Vloggers with noisy environments can replace audio, with the video being the critical content. Recording live music performance/concerts, the audio is the critical content, and having good video is nearly as important.
I have changed cameras a few times already this year Osmo Pocket 3 has given me the best improvement for video.
I am having problems with the audio because the Pocket 3 appears to have very powerful (aggressive) automatic level control for the audio. Observing the audio level indicator on the OP3 LCD, there is almost no dynamic peaking evident, like there is compression or companding with a long time constant. On playback, the background venue noise is actually impressively low, but seems unlike the level indicator display characteristics. Whatever DSP or software processing of the mic signal there is in the camera causes severe frequency response changes. I can only describe this qualitatively as I cannot measure it. For example, a clarinet soloist was now an unrecognizable instrument. The bandleader thought the noise reduction was excellent but the clarinet sounded like a strangled goose.
In a noisy restaurant, the only OP3 mic option that approached usable was 'Front'. Left & Right side mics compound the noise.
I have been recording simultaneously with the OP3 and an Android phone with a 3rd party camera app. The phone has very rapid responding audio level display and produces excellent audio with its native omni- directional ECM . The dynamics are captured. Unfortunately, the omni mic pattern captures all the noise with the music.
Next experiment was purchasing two Rode VideoMic USB-C+ directional mics. The pattern is not detailed. It may be cardioid. Some people call them 'shotgun' but that is merely a visual interpretation. I find they have poor back rejection compared to dynamic cardioid mics.
Both the phone and the OP3 were set up side by side with the same model USB-C mic.
I found the first recording with OP3 and the Rode USB-C mic, in Pro mode, the mic gain default setting was found to be +6 dB. I selected Mono. The 2nd session I set the Pro menu mic gain to -12 dB (18 dB lower, because the audio level indicator was very high and revealed negligible dynamics- minimal peak detection is evident...the audio display is nearly constantly the same level. For the 3rd session, the external mic gain was set to -6 dB.
In 3rd party video editing software, the audio track for all 2nd & 3rd OP3 sessions were extremely low. I do not remember the level on the "+6 dB mic gain setting" video, but the frequency response was unusable, and changes with the audio dynamics, so it cannot be corrected (easily) with audio software editing like EQ.
The reduced mic gain (2nd & 3rd sessions) audio track was so low I thought it would be unsalvageable. But I was wrong. The venue noise (customers in restaurant) seems suppressed as well. I cannot explain how it works, but 'Normalize' as an audio post-process in video editing software restores the 'lost' gain but it's kind of flat, lacking dynamics. A Compression preset in post-processing restores this (must be expansion rather than compression) and the dynamics of the audio are quite pleasing during preview playback. A little EQ help and the audio is almost great, during a quick preview before re-rendering the video with the audio enhancement to a final edit copy..
But listening to each music video end-to-end, the drastic compression or ALC the OP3 appears to be performing, results in transient frequency response shifts - the audio being recorded is not constant amplitude, but the OP3 seems to be trying its very best to produce a constant audio level. Maybe this would be good for voice-only audio, but the results are bizarre. Instruments and a vocalist change in tonal quality as a result of 'controlling' the dynamics.
The phone has no such 'compression'. In a noisy environment, I conclude I cannot utilize the OP3 with it's own microphones or the Rode USB-C mic. It's a fantastic camera. I can probably eliminate a few other cameras, gimbal stabilizers, external mics and preamps! But I can't use the Osmo Pocket 3 audio for live music (have not tried studio or quiet concert venue yet - these are harder to set up and occur less frequently).
Finally, I reach my question /suggestion.
OP3 has approximately 3 or 4 color profiles available to videographers.
If OP3 had a menu for adjustments to the audio 'processing', it would make the camera more versatile. Maybe most users are vloggers and have different requirements and different solutions, like overdubbing voice and music audio as part of their workflow. If such changes could be implemented via a downloadable firmware update, I could keep this camera I've used for 3 evenings & cannot get usable results from.
If it becomes (eventually) a feature in a later version (4? 5?), that doesn't help me.
I do not know what USB-C interface microphones do to signals. I assume they have A/D conversion (and possibly DSP?) because USB-C is a serial data interface with no analog channel.
I only personally know one other musician who uses an Osmo Pocket 3 for recording live music, but his scenarios are very different. His recordings are just 'captures' for himself, not production video (no editing).
Thank you
Murray |
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