Carrying out an an Interview - My experiences - Nick Gilbey
FROM START TO FINISH - FROM A TECHNICAL POINT OF VIEW
Thanks to Ian Noah, Alison and others, there is quite a comprehensive guide to the Workflow needed when undertaking an interview for the History Project. I thought it would be good to set out below my experience of filming interviews for the History Project, through editing to archiving and uploading to the web. The process probably throws up more questions than answers but I thought it would be a good exercise and a starting point for other people to contribute their knowledge . I don’t pretend to know all the technical language. Some of the procedures I have undertaken a certain way I have done because I have been advised it is the best way..
CAMERA FOR FILMING
I use a Sony EX3 camera . It is at the cheaper end of the Sony Broadcast XDCAM series of camcorders which uses Mpeg -2 in the recording section. I am now using HD setting 1080/25p – 1080 the number of lines scanned determining the resolution of the picture ( I can record 720 which uses less pixels but is not considered full HD) . 25 is the number of scans per second. p standing for progressive where there is no interlacing and the camera scans line 1 then line 2 etc. i–interlaced scanning has been the traditional system that has been used for decades broadcasting with 405 and 625 line transmissions. Yorkshire TV, when filming ‘Heartbeat’ using a video camera, de-interlaced the image which was supposed to give it a ‘filmic look’. When I first used progressive on my broadcast dvcam camcorder back in the 1990s, the picture became jerky when I did a quick pan and only became apparent in the edit suite. Things have changed and improved so progressive mode does seem to be the future. It is, so I am told, more computer and web friendly. So in conclusion I think progressive is best to use for The History Project.
This is an extract from Wiki ‘Broadcasting Standards”
For live broadcast applications, a high-definition progressive scan format operating at 1080p at 50 or 60 frames per second is currently being evaluated as a future standard for moving picture acquisition.[needs update] EBU has been endorsing 1080p50 as a future-proof production format because it improves resolution and requires no deinterlacing, allows broadcasting of standard 1080i25 and 720p50 signal alongside 1080p50 even in the current infrastructure and is compatible with DCI distribution formats.https://en.wikipedia.org/wiki/1080p - cite_note-EBU_No1_1080p50-4
Much of my camera set ups have been determined by the requirements of working for the BBC. Some years ago the BBC published a list of cameras that met their broadcast standards. This was written by Alan Roberts who tested all the cameras and checked their specification. The list is no longer a ‘gospel’ as new cameras and technical requirements do change. One requirement for broadcast is a minimum bit rate of 50MB per sec. This is the amount of digital information which is recorded within the camera per second. My present camera records at a maximum of 35MB per sec and the BBC do use other cameras which have this spec. I would suspect not even an experienced broadcast engineer could see on a monitor the difference between a sequence recorded at 35 or 50MB per sec.
And now we have 4K (Ultra High definition), the new standard being introduced with quite a lot of reasonably priced camcorders having this ability. 4K has twice the definition of what we know as ‘full HD’ which could be called 2K. Now the Japanese have come up with Ultra High Definition 8K - where does the story end? The History Project has to decide the best recording standard. Perhaps the best answer, at the moment, is the best each individual can obtain. When the Project updates its own equipment I think originating on 4K will ‘future proof ‘ the recording for sometime, if not decades.
While recording at the best possible standard may be important, the higher the standard, the larger the amount of digital information that has to be processed during the editing and archiving process. I record onto SD cards. (1080/25p at 35MB per sec). Recording at this standard, a 32GB SD card will hold up to a 2hr interview. (The card has to be a quality -10 - capable of 60MB per second).
That is a writing speed of 60mbs which is slower than the reading speed which is often written on the card
OTHER EQUIPMENT NEEDED FOR FILMING.
I use two personal mikes (close miking) . One on the interviewee (ch 1 on the camcorder) and one on the interviewer (ch 2). While many sound recordist will use a boom for the interviewee for a number of reasons, I feel ‘close miking’ is a good compromise as there isn’t a separate person looking after the sound.
I usually use two lights (both soft and dimmable). It was the case that lights where essential to film indoors when film stock and video cameras were not so sensitive. Now the use of lights is not essential but it does mean you don’t have to rely on daylight coming through the window or the lighting already in the room which might be of dubious colour quality. I use lights to give a consistent look to the interview and hopefully a certain ‘shine’.
FILMING THE INTERVIEW
Although the interviews are recorded now on video, I think the prime consideration has to be to choose a place for the interview that is acoustically good. No obtrusive background noise (might be traffic noise) and no bare walls that create an echo and sounds like interviewee is in a bathroom. I find it an advantage if it is a fairly large room for a number of reasons. Firstly I think keeping a good separation between the interviewer and interviewer (6-8ft maybe) is a good idea. It means the interviewee will speak up and thus the other noises will not be so evident. Also the large separation between the two mikes, means the interviewee’s voice will be picked up by the interviewers mike at a very low level. This avoids having to take down of the interviewer’s mike level while the interviewee is speaking, at the editing stage.
The camera lens needs to be on the same level and close to interviewer. Comfy chairs of the same height for interviewer and interviewee are a good idea. I prefer chairs that do not backs that engulf the interviewee. I have found swivel chairs need to be avoided, as the interviewee will tend to swivel during the interview. I prefer to find a pleasing framing for the interviewee, usually a mid shot (waist up) and stick with it. After all, the interview is not going to be edited and I find going ‘in and out’ distracting. Keeping the camera and the interviewer a fair distance from the interviewee does sometimes allow the background to be slightly out of focus. Which can be a pleasing effect.
Using the daylight as a fill light (Or could be called a base light). However it is worth checking, if possible, if the light will be consistent as the I/V will probably last over an hour and you don’t want to keep stopping because the daylight has changed. The same goes for having a window in shot.
I set up the record the level for each mike on the camera just before the recording and then leave it – occasionally checking the level in the viewfinder indicator. I do not use the auto level facility.
Again by choice for editing software has been dictated by my work for BBC English Regions. Some years ago BBC Regions decided to use Final Cut 7 for their ‘outpost’ editing stations. A Quantel system is used in the Regional Centres. I have got used to using FCP7. I find it is not ideal, mainly because of the time it takes to encode the output from the timeline edit which I have put together. (It can take overnight or more for a long I/V.) I will be changing to FCP X but changing means a learning curve again. I suppose most non-linear systems work in a similar way with a timeline for video and audio tracks. For the History Project only a few adjustments usually need to be made. I ingest the material from the SD card using the sequence preset on FCP7 which has XDCAM EX 1080/25p(1920 x 1080 25fps Mpeg 2 - at 35MB per sec with audio at 48khz) or (1920 x 1080 25fps Mpeg 2 – at 35MB per sec with audio at 48khz).
Whatever the settings on the camera, it is probably best to keep them at least through the editing process. Once the clips have been ingested into FCP 7 ( there may be two or three long clips making up the I/V which may be 2 hours long) I put them onto the timeline in order. I then trim them of any unnecessary bits at the start and end and join them together. I use a fade to black effect to join the clips. Sometimes I have used a quick dissolve or maybe just a jump-cut. I set the level of track 1 and 2 (Ch 1 and Ch 2 from the camcorder). Normally the level does not need adjusting throughout the I/V recording as the separation of the two mikes means the mikes can be left open when one or the other person speaks. The I/V is then ready for exporting and decisions have to made.
EXPORTING, ARCHIVING AND UPLOADING
This is an area I find quite tricky with so many options and decisions to make.
The outcome that is desired as I see it is as follows.
A DVD as a record of the interview that can be kept by The History Project.
A suitable copy for uploading to the British Entertainment History Project website and archiving on google drive
A High Definition copy to be kept by the BEHP and the bfi on a hard drive.
I think it is also desirable for the History Project to keep the original SD card/cards
For the DVD, I can just highlight the sequence to be put onto DVD on my timeline and use the ‘Share ‘ option in the FCP7 and choose the DVD option. The sequence will be compressed to produce the DVD. A standard DVD (Capacity 4.7 GBs) can take about I hour of good quality Mpeg 2 video. A standard DVD is single layer. A dual layer DVD can hold up to 2 hours. All DVDs are standard definition.
It is no use just burning a video file to DVD, as this might play on a computer, but it will be just a data file and not formatted to play on a DVD player. A DVD software needs to be used. Most edit software comes with a DVD burner.
EXPORTING FOR UPLOADING TO THE WEBSITE AND ARCHIVING ON GOOGLE DRIVE
Ian and Alison have published a guide about uploading to the Website under the Production Hub heading
I am learning about this process. I have opened a google drive account and can upload the video files to my drive and I imagine I will be able to upload to the BEHP Google Drive. I have not had any success yet using the upload form on the BEHP website. But I am still working on this problem which must be on my computer.
Here are some of my musings about preparing a file to upload.
Here starts the language of ‘wrappers’, codecs, frame rates and bit rates.
I am still learning but I think there is one general rule and that is try to keep the settings the same as you had when the recording was made. That is the same frame rate (for me 25fps), the same resolution ( HD 1080 x 1920). The bit rate will determine the size of the file along with whether you choose –single pass – or multi –pass and of course will determine the quality of the picture.
Google Drive will accept most types of video files – perhaps MP4 (‘wrapper’) which contains the H264 codec and audio file could be the one to choose.
I have put below the Google Drive list of accepted video files then some general advice from You Tube and Vimeo about how to export sequences from various edit software to upload to the web at the best quality. There are also some usefull video tips on how to export from various edit software on this vimeo page.
Video files in Google Drive
Google Drive gives you control over all of your file types in a single place, including video files. With Google Drive, you can:
* Sync or upload video files up to 5 TB in size (limited by available storage space)
* Sync or upload video files in the following formats:
o .WebM files (Vp8 video codec; Vorbis Audio codec)
o .MPEG4, 3GPP and MOV files - (h264 and mpeg4 video codecs; AAC audio codec)
o .AVI (MJPEG video codec; PCM audio)
o .MPEGPS (MPEG2 video codec; MP2 audio)
o .FLV (Adobe - FLV1 video codec, MP3 audio)
* View all of your videos at a glance
* Share videos with other people without ever having to use an email attachment
* Add caption tracks to your video files.
Tips and notes
* Sync or upload your video in the original format and in the highest quality possible. The maximum resolution for playback is 1920x1080.
* Audio and video lengths should be the same, audio and video should start and end at the same time.
Preview and play a video
All of your uploaded videos can be found when you search Google Drive for Videos using the drop-down arrow in the search box. Click a file name to open and play the video using the Google Drive video player.
When you open a video, you'll also see additional information about the file:
* Sharing settings
* When the file was synced or uploaded
* Download previous versions of the file (you can’t view these versions in the video player).
Below are some error messages you might see while trying to watch a video in Google Drive, and some possible solutions.
"The video is not yet processed." or "This video is currently unavailable."
Please try opening the file again later.
"Unable to process this video."
The video file might be corrupted, or the video has been uploaded in a format that doesn't work with the player. Please either choose a different format or try uploading the video again.
Recommended upload encoding settings
* No Edit Lists (or the video might not get processed correctly)
* moov atom at the front of the file (Fast Start)
Audio codec: AAC-LC
* Channels: Stereo or Stereo + 5.1
* Sample rate 96khz or 48khz
Video codec: H.264
* Progressive scan (no interlacing)
* High Profile
* 2 consecutive B frames
* Closed GOP. GOP of half the frame rate.
* Variable bitrate. No bitrate limit required, though we offer recommended bit rates below for reference
* Chroma subsampling: 4:2:0
Content should be encoded and uploaded in the same frame rate it was recorded.
Common frame rates include: 24, 25, 30, 48, 50, 60 frames per second (other frame rates are also acceptable).
Interlaced content should be deinterlaced before uploading. For example, 1080i60 content should be deinterlaced to 1080p30, going from 60 interlaced fields per second to 30 progressive frames per second.
The bitrates below are recommendations for uploads. Audio playback bitrate is not related to video resolution.
Recommended video bitrates for uploads
Video Bitrate, Standard Frame Rate
(24, 25, 30)
Video Bitrate, High Frame Rate
(48, 50, 60)
Recommended audio bitrates for uploads
Resolution and aspect ratio
YouTube uses 16:9 aspect ratio players. If you're uploading a non-16:9 file, it will be processed and displayed correctly as well, with pillar boxes (black bars on the left and right) or letter boxes (black bars at the top and bottom) provided by the player.
A codec is the format in which your video will be encoded. Vimeo accepts most major video codecs, but for best results we recommend using H.264. If you’re uploading High Definition (HD) video, choose the High Profile H.264 setting instead of Main Profile.
When preparing your video for upload, it’s best to maintain the video’s native frame rate when compressing your video. If your footage exceeds 60 FPS, we will automatically reduce the frame rate. If there is an option for keyframes, choose the same value you used for frame rate. Important: Always choose “constant” frame rate instead of “variable” frame rate.
Bit rate (also known as data rate) controls the visual quality of the video and its file size. If your video editing software gives you the option, choose a “variable” bit rate and select a value from the ranges below. You can experiment with different rates if your file is too large or you’re not happy with the quality of your source file.
Bit rate (kbit/s)
2,000 – 5,000
5,000 – 10,000
10,000 – 20,000
20,000 – 30,000
30,000 – 60,000
Videos come in all shapes and sizes but these are some of the most common formats.
Standard Definition (SD)
4:3 aspect ratio
640 ? 480
Standard Definition (SD)
16:9 aspect ratio
640 ? 360
16:9 aspect ratio
1280 ? 720
16:9 aspect ratio
1920 ? 1080
16:9 aspect ratio
2560 ? 1440
16:9 aspect ratio
3840 ? 2160
Codec: AAC-LC (Advanced Audio Codec)
For best results, we recommend using AAC-LC (low complexity) for the audio codec.
Data rate: 320 kbit/s
For best results, encode your audio at constant rate of 320 kbit/s.
Sample rate: 48 kHz
For best results, set your audio sample rate to 48 kHz. If your working setting is already less than or equal to 48 kHz, leave it as is.
ARCHIVING FOR bfi HARD DRIVE AND POSSIBLY BEHP HARD DRIVE
I think we need to know from the bfi how the valuable interviews should be stored on a hard drive. I have found that exporting a 90 minute interview from my imac FCP 7 at high quality as a Quicktime movie created a file of 101 gigabites.
As you will have gathered this is very much a draft document to open up discussion about the best practice will follow.
1st August 2016