View Full Version : How about good quality Audio?
Bernard Racelis December 19th, 2008, 06:16 AM It's best to slow down the 30p video to 29.97, dropping one frame in 1,000. This solution keeps your video at the correct duration, and is still at real time, more or less. No need to stretch your audio either.
What tool/workflow do you use/recommend ?
I'm using Windows.
Also, even without slowing down the video, I find that I still need to stretch/shorten the separate audio track (5 minutes long) to synch with the video (I'm using Vegas and Sound Forge to stretch/shorten the audio track). That was with an MP3 file though. Need to test this with WAV files.
Jon Fairhurst December 19th, 2008, 12:00 PM What tool/workflow do you use/recommend ?
I'm using Windows.
After Effects is excellent at handling multiple frame rates and providing good control over the result. It lets you specify everything, including selection of speed change vs. frame drop/double vs. frame blend vs. motion interpolation.
One caveat: motion interpolation is slow and flawed. There are plugins available, but I have yet to see anything I like for non-computer generated material.
For the 5D, going from 30p to 29.97, either slow down the video/audio or drop every 1000th frame. And for 30p to 24p, I'd generally drop every 5th frame.
On slow shutter material, like a smoothed out waterfall shot from a tripod, go with frame blending.
Guy Cochran December 19th, 2008, 05:14 PM If you jump over to the BeachTek site, it looks like they're going to be offering an XLR adapter with phantom power and headphone monitoring specifically for the Canon EOS 5D Mark II. BeachTek website (http://beachtek.com/)
Matthew Roddy December 19th, 2008, 05:45 PM If you jump over to the BeachTek site, it looks like they're going to be offering an XLR adapter with phantom power and headphone monitoring specifically for the Canon EOS 5D Mark II. BeachTek website (http://beachtek.com/)
I've been searching and can't really find a good answer to this, but, what's the point of bringing your pro audio into this camera as long as it has auto-gain so integrated?
I've heard/seen a few examples on Vimeo where they use a nice shotgun plugged straight in to the 5dM2 and it sounds good until there's quiet. Then you can really clearly hear the audio levels creep up during those quiet times.
And worse, the levels drop for a loud noise and take a while to recover - just like any auto-level camera/setup.
I don't specifically remember the video, but they were showing a guy who was talking; he tapped something, producing a light mettle CLANG and the levels dropped to compensate, taking his voice with it.
Even taking audio in via pro mics into the 5DM2 via XLRs into a Beachtek wouldn't fix the auto levels, right?
Near as I can tell, the only thing the camera's audio is good for is reference.
I must be missing something obvious.
Mike Calla December 19th, 2008, 10:28 PM Agreed, auto gain in audio is just bad! When audio is even slightly important to your shot/production you need a separate audio recorder!
maybe some one can make an audio recorder (or any device) that has a universal record button. you press "record" and all your devices start recording at same time. Although i guess each device will have different stop to record times, it would still make things a lot easier!
Mike Calla December 19th, 2008, 10:55 PM First, to Salvador, Jon, Bernard and anyone else, my apologies for being confused and formerly posting wrong info regarding time code and the 5D. I’m reading too many threads on too many forums!
As for converting 30p to 29.97 do you complete your edit at 30fps first then do your conversion OR do you covert your clips to 29.97 and then edit?
BTW having my eyes opened to the fact that 5D is in fact true 30fps and not 29.97 non-drop, is to me more of a pain in the ass than all the other problems I’ve been reading about and trying to find workflow workarounds for! Sooner or later the ratio of pain-in-ass:beautiful images is going to be too high to ignore :(
Jon Fairhurst December 20th, 2008, 12:04 AM As for converting 30p to 29.97 do you complete your edit at 30fps first then do your conversion OR do you covert your clips to 29.97 and then edit?
It's probably easiest to do at the end, but if you're going to intermix 29.97 content, then definitely convert up front. Then again, if you have 10,000 30p clips and one 29.97 clip, convert the odd clip to 30p, edit, and then go to 29.97.
It definitely and certainly all depends. :)
Jeff Rotz January 19th, 2009, 01:07 PM I've been searching and can't really find a good answer to this, but, what's the point of bringing your pro audio into this camera as long as it has auto-gain so integrated?
I've heard/seen a few examples on Vimeo where they use a nice shotgun plugged straight in to the 5dM2 and it sounds good until there's quiet. Then you can really clearly hear the audio levels creep up during those quiet times.
And worse, the levels drop for a loud noise and take a while to recover - just like any auto-level camera/setup.
I don't specifically remember the video, but they were showing a guy who was talking; he tapped something, producing a light mettle CLANG and the levels dropped to compensate, taking his voice with it.
Even taking audio in via pro mics into the 5DM2 via XLRs into a Beachtek wouldn't fix the auto levels, right?
Near as I can tell, the only thing the camera's audio is good for is reference.
I must be missing something obvious.
I agree with you, and today I discovered a clever solution for synchronizing an external audio recorder to the 5D Mark II, using the 5D Mark II's audio track as a time code reference track.
Microphone for 5D mkII - FM Forums (http://www.fredmiranda.com/forum/topic/708844/0#6397372)
A little lower in the thread he has posted a diagram of his solution. He proposes using a Zoom H4 with a SMPTE LTC time code track already recorded on its memory card. Because the H4 can playback at the same time as it records, he suggests sending the LTC via a wireless link to the 5D Mark II. Then the video and audio will have the same LTC tracks attached and can be easily synchronized in an editor. Credit to "jray" there for this idea.
Has anyone tried this? Or what about attaching a portable time code generator with LTC output to the audio input of the 5D Mark II and jamming it to the time code generator in an external audio recorder? Frame accuracy isn't essential, just good lip synchronization. The less manual work needed to synchronize the video and the audio recordings, the better it is for all of us who record sound too.
Henry Coll January 22nd, 2009, 08:00 PM I dont know if this has been mentioned, but i'd simply get a fostex FR2-LE.
There's no way to get decent audio into the 5D2. Period. The only way to go is with an external recorder, and sync later in post (use a slate), it takes seconds. That on the other hand brings new possibilities, as the mics can be put anywhere, like far away from the camera and close to the source, if you're shooting with a tele lens, and you won't need radio transmiters for the mics.
Unfortunately, all the cheap audio recorders are full of compromises, either dont have 48v, or don't allow proper confident monitoring and have weak and hissy phone outs, or their preamps are very poor, or the AD is subpaar, etc, etc. Think that of mic as the lens, and the preamp+A/D as the CCD. Quality costs.
I mean, you spend many thousands in the camera, lenses, a video editing software etc, and then pretend to skip on the the audio, which is 50% of videography? Cheap solutions will be like using the kit lens from an entry level DSLR, you wouldn't do that.
This is not photography. Consider that audio gives continuity to images. Keep a good audio source and you can mix all kinds of video footage, regardless of picture quality, colour correction etc. The audio keeps it consistent. Now do the opposite, get perfectly edited and colour corrected footage and pair it with poor audio: it falls apart.
There's no other way to it (if you care about it) than to get a pro recorder, which are all quite expensive, starting from $1,000 up to $6,000. Under the $1,000 mark, the best deal (i've done comaparisons) is with the LE version of the Fostex FR-2, which can be found for $500 or less. It doens't have many features, but what it has, it's up to professional specs, and it's an unit you can use for any kind of proaudio work, even including classical music (for which I'd use at least hi-end external pres though, but im an audio engineer in another life).
Anyway, chek it out. It's not the cheapest option, but one to consider.
William Chung January 26th, 2009, 10:33 AM how about acceptable audio?
are those shotgun mics that can mount on the flash shoe on the camera good enough for something like an interview during an event? will it still catch the annoying IS motor sound?
Joshua Fulton January 27th, 2009, 05:24 AM There's no other way to it (if you care about it) than to get a pro recorder, which are all quite expensive, starting from $1,000 up to $6,000.
What about the Zoom H4? That actually does provide 48 volts as far as I know. I hope it works well, since I just bought one.
Anyway, I'm buying up all the little pieces I need to hopefully start working with the 5d Mark II.
Jon Fairhurst January 27th, 2009, 11:23 AM What about the Zoom H4? That actually does provide 48 volts as far as I know.The options for powered mics are the Zoom H4, the Zoom H4n (not shipping just yet), and the M-Audio Microtrack II. The Microtrack has 1/4" TRS inputs, so you need an adapter cable, but given that, it works fine with dynamic mics.
I'm a few hundred miles from our production right now, but I heard a short bit from our Microtrack capture last night. It's a bit darker than I expected with our mic/environment, but I was able to boost the highs and they came through without any appreciable noise.
I don't know about the Zoom, but given the Microtrack results I heard last night, I'd upgrade to a top mic first, and a top recorder/mixer second.
Keith Paisley January 27th, 2009, 11:34 AM The options for powered mics are the Zoom H4, the Zoom H4n (not shipping just yet), and the M-Audio Microtrack II. The Microtrack has 1/4" TRS inputs, so you need an adapter cable, but given that, it works fine with dynamic mics.
I'm a few hundred miles from our production right now, but I heard a short bit from our Microtrack capture last night. It's a bit darker than I expected with our mic/environment, but I was able to boost the highs and they came through without any appreciable noise.
I don't know about the Zoom, but given the Microtrack results I heard last night, I'd upgrade to a top mic first, and a top recorder/mixer second.
The microtrack ii works decently well with dynamic mics but if you are trying to pick up detailed low level sounds I found that pre-amp can be a little bit noisy. I poked around the M-audio site and found that M-Audio even says it's not optimal for dynamic mics. From their FAQ page (http://www.m-audio.com/index.php?do=support.faq&ID=9a237a0b77a1865fb5f66e14d146b6c6):
Dynamic microphones can be used, however due to the low sensitivity of a dynamic microphone it's necessary to boost input gain, resulting in a higher noise level. For best quality results we recommend phantom powered condenser or electret microphones.
A workaround I plan to try is to use my wireless sennheiser setup to see if I can get cleaner signals using the sennheiser's pre-amp.
Jon Fairhurst January 27th, 2009, 01:03 PM The microtrack ii works decently well with dynamic mics but if you are trying to pick up detailed low level sounds I found that pre-amp can be a little bit noisy. I would think that most of us would be using condenser, rather than dynamic mics, so this shouldn't be an issue.
Guy Cochran January 27th, 2009, 03:50 PM I've been searching and can't really find a good answer to this, but, what's the point of bringing your pro audio into this camera as long as it has auto-gain so integrated?
I've heard/seen a few examples on Vimeo where they use a nice shotgun plugged straight in to the 5dM2 and it sounds good until there's quiet. Then you can really clearly hear the audio levels creep up during those quiet times.
And worse, the levels drop for a loud noise and take a while to recover - just like any auto-level camera/setup.
I don't specifically remember the video, but they were showing a guy who was talking; he tapped something, producing a light mettle CLANG and the levels dropped to compensate, taking his voice with it.
Even taking audio in via pro mics into the 5DM2 via XLRs into a Beachtek wouldn't fix the auto levels, right?
Near as I can tell, the only thing the camera's audio is good for is reference.
I must be missing something obvious.
The pre-production BeachTek DXA-5D is specifically engineered to compensate for Auto Gain by generating a high pitched tone which is inaudible to the human ear. The high pitch tone keeps the audio at a consistent level.
Krishna Narayanamurti January 27th, 2009, 04:04 PM The pre-production BeachTek DXA-5D is specifically engineered to compensate for Auto Gain by generating a high pitched tone which is inaudible to the human ear. The high pitch tone keeps the audio at a consistent level.
Guy, that's an awesome solution for the auto gain problem. Very clever idea by Beachtek. Can't wait for the dxa5d to finally be released.
My only concern, though, will the high pitch tone be harmful to household pets or Superman? :)
Matthew Roddy January 27th, 2009, 04:07 PM The pre-production BeachTek DXA-5D is specifically engineered to compensate for Auto Gain by generating a high pitched tone which is inaudible to the human ear. The high pitch tone keeps the audio at a consistent level.
Well that's fairly ingenious and amazing.
Does that solve all problems from silent times (I can see how it would) to loud hits?
How does that all fair in Post?
Brian Boyko January 27th, 2009, 05:11 PM Go double system. Use a good quality camera for the video and a good quality digital recorder for the sound. Invest a few bucks in a simple slate, or make one.
I've never had any synch problems with my MicroTrack, plus it's nice not having to tie the camera to the sound guy with a long cable. Hollywood got along just fine for decades using reel-to-reel Nagras with 1/4" tape. If you're really concerned about losing sync, do a tail slate at the end of the shot along with the slate at the beginning, and see how well it lines up with the video.
People act like it's such a hard thing to sync up a separate audio track with video. Slated properly, you have a wonderful single spike on the audio track waveform when the clapsticks close, which you line up with the video frame showing when the sticks close together. Takes maybe five seconds. Once aligned, group the audio clip with the video clip in the timeline, and they can be moved, edited, and shifted as a single item.
Martin
Even simpler - every camera has at least onboard audio. Looking at the waveform, you should be able to see a spike on the VIDEO's waveform as well as the seperately recorded audio. You can literally line the two spikes up and get perfect matching.
Rick Hill January 27th, 2009, 10:12 PM I wonder if you could feed the audio input with some kind of jam or reference signal, an ultrasonic one that only dogs can hear, at a constant or adjustable level, which would then set the auto gain accordingly. Then you could filter out the jam signal in post, and have your human audio where you want it.
I have thought about this for a while now. My original idea was to use something like this for other camcorders with mic inputs and auto-gain (then I bought a HV-30).
I think the idea is sound. You could go with either a ultra-low frequency (20-50 Hz) or ultra-high (15Khz to 20Khz). I think an ultra-low frequency would work better since I would expect better frequency response from the recording circuitry here. But I'm splitting hairs - experimentation could show which is better if there is a difference anyways.
The key design parameters are the ratio from the pseudo subsonic signal to the mic signal has to be well matched. You don't want any audio spikes overloading the input (over the subsonic signal) or the agc will kick in. On the other end you don't want the subsonic signal too high in relation to the mic signal or it will be more diffiicult to filter out in post.
The overall gain of both has to be well matched to the auto-gain circuit as well to get the best dynamic range without overloading - quite similar to adjusting manual gain for manual gain capable camcorders - except there's no indicators to help you here.
Could be a fun project someday . . .
On another note - regarding seperate audio recording - there is a big issue I have experienced myself. I record audio for my band and use seperate audio recorders to do it. It just so happens I have both a Maudio Microtrack _and_ a Zoom H4. I keep one recorder on stage to record the band instruments via two PZM mics. The other recorder goes to the house PA to pick up the Vocals and any PA amplified instruments straight off the board. I have also recorded video of the band with these recorders capturing the audio in the same fashion.
Both of these recorders have issues with the internal clock sources. They are no where near each other and neither ever matches the camcorders. The funny thing is when I use multiple camcorders they are never off by more than one frame (audio+video). I guess camcorders have significantly better clock sources then either of these recorders do.
Anyways, when I sync all the audio in post the difference between either recorder and the camcorder is startling. It is very easy to find the opening notes of a song/clip to begin sync but very quickly you can start hearing the sound phasing (caused by one signal lagging the other) and then it starts to sound like a slapback echo. BY the end of the song it sounds like avant garde music - LOL.
The fix is to time stretch the audio (I find an opening cue point and an ending cue point. I calculate the delta in time and then apply the stretch accordingly - using the camcorder audio time frame as the "golden reference"). I use Cubase 4 and it has the ability to do this. It works very well but it is a pain in the butt.
YMMV but something to consider with either the Microtrack or Zoom H4 since they both have this issue.
Jon Fairhurst January 27th, 2009, 11:33 PM YMMV but something to consider with either the Microtrack or Zoom H4 since they both have this issue. Do you have the original Microtrack, or the Microtrack II? The second generation had a number of important improvements - better preamps, improved handling of unbalanced mics in the 1/4" inputs, full 48VDC phantom, rather than ~30VDC...
Also, any preference in sound between the two?
I had read that the H4 had some noise from the blinking LED, but I'd imagine that was on the unbalanced inputs or onboard mics, rather than the XLRs.
Henry Coll January 28th, 2009, 06:35 PM What about the Zoom H4? That actually does provide 48 volts as far as I know. I hope it works well, since I just bought one.
Anyway, I'm buying up all the little pieces I need to hopefully start working with the 5d Mark II.
Depends on on where your bar is. I am, among many other things, a professional audio engineer, and to me the differences between cheap and pro gear are easily noticeable. Also, these days ALL manufacturers lie with specs. For instance having 48v doesnt mean the mic is continually sourced with this current without any voltage dropout, or how long the recorder's batteries will last when giving 48v away (maybe minutes instead of the 8 hrs from pro units). Same when they present frq responses, or A/D/A, and they say nothing about the analog circuits feeding those converters, etc etc.
Im not saying the zoom might a bad unit as i havent used, but i tried other zoom products and i found them products for the average consumer.
Some people might be satisfied with a rode mic into the canon. I wouldn't set for anything
less than a sennheiser MKH or Schoeps mic along with a pro external audio recorder.
And later in post, I would pay as much attention to audio as to video, building a soundtrack in layers, with all the classical elements if required: (production) dialog, ADR, foley, walla, fx and music (and all at 48khz/24bit ).
Rick Hill January 29th, 2009, 07:35 AM Do you have the original Microtrack, or the Microtrack II? The second generation had a number of important improvements - better preamps, improved handling of unbalanced mics in the 1/4" inputs, full 48VDC phantom, rather than ~30VDC...
Also, any preference in sound between the two?
I had read that the H4 had some noise from the blinking LED, but I'd imagine that was on the unbalanced inputs or onboard mics, rather than the XLRs.
I have the first Microtrack. I am quite happy with the sound quality from both. Since I am doing live recording from PZM's and PA feed I am not using the phantom function (or onboard mics) and I am sure I am not feeding in the best signal possible to really test the units. My biggest beef with both is the clock source issue.
My second beef is battery life for both are awful. The Microtrack has a non-replaceable internal battery that goes dead whether it's powered up or not. And for being a LiON battery it's stay alive time when charged is pathetic. The Zoom H4 also eats batteries (2 AA's) like they are going out of style.
Luckily for me I bought both of them them for convenience, price and size - not battery power. [Note - I was hoodwinked into the Zoom H4 thinking I could do 4 simultaneous track recording with the 2 onboard mics + 2 offboard mics - nope can't be done] You could always use battery packs and power cord adapters to drive them for better battery life.
One more note - they are targeted to practicing musicians so yeah, they both probably are not what one would consider pro-quality "field" recorders. If you are looking for "studio" grade recording in a field recorder there are much better (and more expensive) options out there.
Noah Yuan-Vogel January 29th, 2009, 12:42 PM Heres what I am stongly considering doing for my 5Dmk2. It is important to me to be able to record audio in cameras since syncing in the edit is not the best option for every format of shooting (reality, doc, event, web).
I've been looking at the Azden FMX-32 field mixer which is less than half the price of a sound devices mixpre with similar capabilities (phantom power, vu, etc but no built in tone or slate mic). The azden mixer seems to have better battery life, headphone amp/monitor built in and is less expensive compared to a beachtek (DXA-6vu is what i was considering before).
according to john saunder's tests (Canon 5d Mk2 Audio Test on Vimeo (http://www.vimeo.com/2851797)) and also it sounds like a similar route to what beachtek is taking, applying a consistent tone to the channel will prevent agc from activating, and the agc is linked for both channels, so worst case you apply a tone to R channel to control agc and record actual audio to L channel. And a 3 channel mixer would allow for one xlr tone generating dongle (like this Goldline GL1K*::*Test Equipment*::*Toolbox*::*Installations*::*Blue Dog Audio (http://www.bluedogaudio.com/goldline-gl1k-pr-841.html)) on channel 3 mapped to R output and leave 2 xlr inputs that can be mixed into the L output channel. Of course if we could do what beachtek does and use a high-freq tone that does not interfere with other recording on the same channel (and doesnt need to be removed in post??), I might actually be able to get two recordable agc-free channels. anyone know what kind of tone generator might be appropriate for this? might be tough to monitor the channel with the tone and mic input on it since the VU meter would probably just read the peak of the tone... maybe there is a way to apply the inaudible tone after the mixer before the camera?
anyone see any holes in this plan? any suggestions?
if it works it seems pretty reasonable and flexible compared to beachtek's options which seem more expensive in general. maybe if beachtek released modular products it would be more helpful, like making a agc-defeating in-line inaudible tone generator or something.
John Saunders February 9th, 2009, 09:59 AM As Noah said I did some audio tests with my mixpre and tone to see how the ACGs react. Here they are if anyone is interested.
Test with 1khz tone
Canon 5d Mk2 Audio Test on Vimeo (http://vimeo.com/2851797)
Test with ultra high and low tones
Audio test for 5DM2 extreme low and high frequencies on Vimeo (http://vimeo.com/3072099)
Hope that helps.
Michael Schoenfeld February 9th, 2009, 10:18 AM Hey everyone,
Michael Schoenfeld here,
I use the Zoom H4 - it's pretty good based upon what mic you attach.
I have two options - Beer, and champagne.
Sennheiser G2 with a Countryman B6 (Beer)
Schoeps CMIT5 (Champagne)
The tricky part is not to forget that the "normal" file will be 30P, NOT 29.97 in the US of A, so it needs to be conformed with some tool so the movie AND the audio file will sync perfectly.
I conform all my files with MPEG Streamclip to 29.97 and the audio sync works that way - the timeline wants to make the clip "out of sync" with the H4 file because of this stupid Canon thing - why oh why Canon, are you not making this camera pro friendly (I "know" the answer (as good as anyone can) so no flames, please).
The nikon and zeiss glass is the only way to fly with this beast right now - thanks Canon,
Michael Schoenfeld
Keith Paisley February 10th, 2009, 08:25 AM Hey everyone,
Michael Schoenfeld here,
I use the Zoom H4 - it's pretty good based upon what mic you attach.
I have two options - Beer, and champagne.
Sennheiser G2 with a Countryman B6 (Beer)
Schoeps CMIT5 (Champagne)
The tricky part is not to forget that the "normal" file will be 30P, NOT 29.97 in the US of A, so it needs to be conformed with some tool so the movie AND the audio file will sync perfectly.
I conform all my files with MPEG Streamclip to 29.97 and the audio sync works that way - the timeline wants to make the clip "out of sync" with the H4 file because of this stupid Canon thing - why oh why Canon, are you not making this camera pro friendly (I "know" the answer (as good as anyone can) so no flames, please).
The nikon and zeiss glass is the only way to fly with this beast right now - thanks Canon,
Michael Schoenfeld
Just to clarify, are you having synch problems when putting 5d footage on a 29.97 timeline or are you having problems even on a 30.00 fps timeline? I ask because I ran some tests of several long clips (using MP3s captured simultaneously with a microtrack II) and with Vegas I'm seeing something on the order of perhaps 10ms of drift across a 13+ minute segment. It doesn't seem to matter whether or not the project is set at 29.97 or 30.00 fps.
Bill Binder February 12th, 2009, 12:16 PM People, this is not that difficult to understand. No one should be expecting perfect sync for long periods, it really is that simple.
If you are: (1) using a separate device to record audio and (2) not fully timecode jammed/synced, then drift will -- in all likelihood -- occur to some extent or another. That's true for even the most pro recorders in existence and may occur regardless of 30 or 29.97 fps or 44.1 vs. 48 kHz. Even two SD744s will potentially drift from one another over extended times if they aren't jammed, and that's two of the exact same high end units.
So, if you don't have drift problems over extended periods, you should consider yourself lucky, and if you do have drift issues, you should consider that to be pretty normal.
Brian Boyko February 12th, 2009, 12:51 PM To me, the dual-system single system comes down to one thing: Redundancy. One little blip of static can ruin a shot unless you have a second audio source.
(In one particularly telling moment, my acting-DoP, who was really my PA, who was filling in for my REAL DoP who was arrested for terrorism - long story - actually forgot to turn on the microphone for a few minutes while recording. I'm damn glad the backup audio was running then!)
I record dual system when I can, but I always make sure to use the really good stuff on the camera if I have to choose between the two. I'd rather have a good audio track on the camera than have to sync in post.
I've recently become a convert to the XLR workflow - get a Juicedlink or Beachtek - I prefer the former for the preamp - and you should be fine.
Peer Landa March 4th, 2009, 08:07 AM For music I use the Apogee Duet to a Macbook Pro (Mac only):
Apogee Electronics: Products: Duet (http://www.apogeedigital.com/products/duet.php) This has an A/D converter close in quality to their recording studio products.
Although Apogee has always made topnotch products, I still would recommend a Sony PCM D-50 for this kind of usage that we're talking about here.
-- peer
Jason Linn March 4th, 2009, 11:55 AM does anyone know of a way to monitor mic levels BEFORE they get into the camera? I was thinking some type of small adapter that the mic could plug into before going to the mic input on the MK2?
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