I am a first time user of OBS and I am trying to use it to record my church's worship gatherings so we can put them online for people. I am using a sony HVR-V1U camcorder hdmi out to Blackmagic mini recorder thunderbolt to MacBook pro. Can anyone help me figure out the best settings for the video to not lag and line up with the audio (forgot to mention I have audio going into mixer and then into camera)? I am possibly trying to get too much output trying to record at 1080p. I am not a AV wiz so in my mind I go toward the best quality output, but obviously that isn't working. If anyone can help me I would be greatly appreciative! Thank you!
Question / Help Need Help setting up blackmagic mini recorder and OBS
- Thread starter dJones
- Start date
Metryq
New Member
Audio delay is typical in digital video systems. (It showed up in some analog systems, though not so much.) The delay is caused by the processing time between the image striking the sensor in the camera and final output as HDMI, SDI, IP video, etc. Audio processing is "instantaneous." So you must delay the audio to match the video.
OBS has audio delay built-in under the Advanced Audio Properties, and the delay is adjusted in milliseconds (thousandths of a second). You know those old clapper slates used in filmmaking? You can substitute by clapping your hands together, but be sure your hands are clearly visible. Record a clap test, take it into an editor like Final Cut, Premiere, DaVinci or whatever and find out how many frames there are between the sound of the clap and the hands coming together (no blur). Some editors will allow you to hear the audio as you step frame-by-frame, and most will show you an audio waveform where the clap will appear as a sharp spike.
(If you do not have video editing software already, there are many free, open source options.)
The amount of delay will depend on the camera, and cameras are getting better all the time. Let's say you have 4 frames of delay, which makes each frame 33.33 ms for 30 fps video (1000 / 30). Set the delay in OBS to 133 ms and take another clap test.
This sort of delay does not happen with camcorders because the manufacturer has already built-in a delay circuit to the audio. If you plug a mic into the camera, the delay is taken care of for you. And any video-with-audio-embedded (HDMI, SDI, etc.) will be synchronized for you. The problems occur when audio and video are handled separately.
Thankfully, OBS has a built-in delay. All-in-one video switchers like Tricaster or Broadcast Pix also have built-in delay controls. But what if you are using something like the popular Blackmagic Design ATEM switchers? For that setup you would need an external audio delay. The Behringer FBQ100 is about the least expensive unit I know about. It is monophonic, but accepts both line and mic levels, outputs both line and mic levels, has balanced and unbalanced input/output, and features a host of other useful functions, like feedback suppression.
OBS has audio delay built-in under the Advanced Audio Properties, and the delay is adjusted in milliseconds (thousandths of a second). You know those old clapper slates used in filmmaking? You can substitute by clapping your hands together, but be sure your hands are clearly visible. Record a clap test, take it into an editor like Final Cut, Premiere, DaVinci or whatever and find out how many frames there are between the sound of the clap and the hands coming together (no blur). Some editors will allow you to hear the audio as you step frame-by-frame, and most will show you an audio waveform where the clap will appear as a sharp spike.
(If you do not have video editing software already, there are many free, open source options.)
The amount of delay will depend on the camera, and cameras are getting better all the time. Let's say you have 4 frames of delay, which makes each frame 33.33 ms for 30 fps video (1000 / 30). Set the delay in OBS to 133 ms and take another clap test.
This sort of delay does not happen with camcorders because the manufacturer has already built-in a delay circuit to the audio. If you plug a mic into the camera, the delay is taken care of for you. And any video-with-audio-embedded (HDMI, SDI, etc.) will be synchronized for you. The problems occur when audio and video are handled separately.
Thankfully, OBS has a built-in delay. All-in-one video switchers like Tricaster or Broadcast Pix also have built-in delay controls. But what if you are using something like the popular Blackmagic Design ATEM switchers? For that setup you would need an external audio delay. The Behringer FBQ100 is about the least expensive unit I know about. It is monophonic, but accepts both line and mic levels, outputs both line and mic levels, has balanced and unbalanced input/output, and features a host of other useful functions, like feedback suppression.