FS5 - R U shooting 25/30p or 50/60p?
 

I was wondering what folks are mostly shooting in on their FS5's and why? Being in PAL land thus far I've mostly been using XAVC HD 1080/50p 50mbps. But maybe I'm doing myself a diservice in terms of the extra processing needed in Premiere (compared to 25p) and the extra storage.

On a connected note, would it be worth transcoding into Prores before editing in Premiere to take the strain off of the CPU re XAVC-L? I tend to use quite a few filters/plugins for grading like Magic Bullet Looks, Neat Video, etc.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

To my knowledge 25p and 50p records at the same bit rate. 50p increases temporal resolution i.e. smooth motion (no judder) in panning shots, as smooth as 50i. both records at same data rate (Mbps). Could be more compressed. So storage requirement is same.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Are you shooting for yourself or for clients? I pretty much try to shoot in whatever format my clients will be finishing to -- which means 90% of the time it's either 30p or 24p. If you think you may want to slow any of the footage down it's worth shooting at the higher frame rate to have the extra frames to work with.

In terms of the transcoding question -- your edit system/workflow is the deciding factor. If you find that the XAVC-L brings your system to its knees then by all means transcode. But if you are fine staying with the original camera format then my suggestion would be not to spend all that transcoding time. Remember, each transcoding process can create artifacts (no matter how slight). I'm assuming it's probably unlikely that you will be outputting to XAVC-L -- so eventually your edit system will be transcoding to your output format.

Do a real-world style test edit and see how your system reacts -- then you won't be surprised. But also test your transcode times for a full card of data! I have one client who wants not only my original camera footage but a prores copy as well before we leave location. Needless to say we're always waiting for that part to finish after we've packed all the gear!

Re: FS5 - R U shooting 25/30p or 50/60p?
 

I shoot everything in 30p unless I am going for slow motion, in which case I'll shoot 60p or 240p. I personally am not a fan of 24p, as I don't like the motion artifacts, and really 30p looks the same, but you can pan without judder. Shooting in 60p and editing in 6op results in a glassy look similar to video tape. Not filmic at all. Maybe if you are doing fast paced sports 60p is appropriate. Much of what I shoot ends up on TV (commercials), so 30p is right for that. In PAL land I would stick with 25p unless you plan on slowing down the footage, or if the client specifically asks for something different.

Also at 50p the appropriate shutter speed is 100, so you are robbing yourself of a lot of light. At 25p the shutter should be 50, and you will get away using less gain/ISO for a cleaner image, not to mention that every frame has more bits (2 times as much).

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Thanks chaps. Useful feedback. I'll try my next small project/interview in 25p and see how that turns out. Chad why would I lose the extra 2 bits at 50p? Isn't it also 10 bit in XAVC HD?

Re: FS5 - R U shooting 25/30p or 50/60p?
 

What I meant was that if you shoot at 50fps at say 50mbps, you are getting half as many mbps per frame as if you shoot at 25fps at 50mbps. Does that make sense?

Re: FS5 - R U shooting 25/30p or 50/60p?
 

That doesn't sound right, you are basically saying that 50p would then only be 25mbs, the data rate remains the same if you shoot 25p or 50p, only with 50p you get twice as much frames as in 25p.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Noa. I think what Chad is getting at is that in XAVX-L you have 50Mbps of data per frame at 25p or 50p. In the case of 25fps that means you have 2Mbps data space for each frame. if you now record 50p with the same data rate, in this case 50Mbps you only have 1Mbps per frame as there are now twice as many frames to record using the same 50Mbps data rate.

For example a 64GB card in XAVC-L at 1080 50p gives you 143 minutes of data storage. 1080 25p still gives you only 143 minutes. With 50p being twice as many frames as 25p to be able to maintain the same data packing density the 50p should really be recorded at 100Mbps.

Likewise if you switch to XAVC-L 720 50p you still have 143 minutes on a 64GB card. If fixed at 50Mbps the difference here though is that the 720 50p has a much more efficient less compressed packing density than either of the 1080 flavors. At 1920 x 1080 in square pixels the pixels per frame storage requirement is 2,073,600 pixels per frame whereas at 1280 x 720 the pixel count is less than half at 921,600 per frame.

The way I understand it the math for HD is as follows

1920 x 1080 @ 50p = 103,680,000 pixels to store in 50Mbp of storage
1920 x 1080 @ 25p = 51,845,000 " " " " " " "
1280 x 720 @ 50p = 46,080,000 " " " " " " "
1280 x 720 @ 25p = 23.040,000 " " " " " " "

For the lowest compression and the best handling of very complex fast changing data 1280 x 720 is more efficient than either of the 1080 formats by a factor of x 2.
The above of course does not take into account other factors such as 4:2:0 vs 4:2:2 and 8-bit vs 10-bit encoding depths. Factors that again can have more or less impact on storage efficiencies depending on the codec and bit rates in question.

It's a different story if you look at Sony's XAVC-I implementation because if you go from 25p to 50p the data rate increases by a factor of x 2. In 1080 HD it goes from 111Mbps to 222Mbps.

Sony FS7 FAQ - Frequently Asked Questions

The fact that Sony, unlike any other manufacturer in H.264 Long GOP codecs, uses real time Dual Pass VBR in both its L and I frame variants and it's that which enables such good quality at these lower rates which is quite some achievement. We live in amazing times.

Chris Young
CYV Productions
Sydney

Re: FS5 - R U shooting 25/30p or 50/60p?
 

It's nice to know the mathematics behind it but what would be more interesting would be what it does matter in real life shooting. On my camera's I don't see any difference between shooting 25p or 50p when I visually compare the footage and by that I don't mean pixel peeping but to look at it from a normal viewing distance, the main difference I see is when I start to pan.

Nigel wanted to know if XAVC HD 1080/50p 50mbps vs XAVC HD 1080/25p 50mbps would make much difference in post, I think it's more important to realize what the consequences are when you shoot in 25p if you want to slow down the footage in post or if you shoot fast action scenes where faster panning is involved. That should be the main concern, not if 25p or 50p would make a big difference when stressed in post because my personal experience is that it doesn't but that is on a faster desktop machine and might be different on a slow laptop.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

50mbps. That's 50mb per second no matter what the frame rate is. So shoving more frames into that second results in each frame having less resolution. Less resolution may not show much if you don't grade your footage, but push it a little and it breaks down. Not to mention you lose the amount of light hitting the sensor. But mainly, it just looks like video tape - all glassy. Nobody likes that look. You may as well shoot at 60i if you are trying to look like video tape.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Well, about 100 clients I delivered to the last years would disagree on that statement. :)

Can you show that in a few framegrabs that 50p results in less resolution compared to 25p? I"m not seeing it.

I shoot at 50p at 1/50 shutter all the time so there is no loss in sensitivity compared to 25p, it looks exactly the same to me.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Did your clients ask for 60p footage? If they did, than that's what they want and 60p is appropriate. In my experience most clients don't know what's going on enough to discern between a filmic look of 30p vs a video tape look of 60p. That doesn't mean I shouldn't use my expertise to choose the appropriate settings.

I'm not going to do your research for you to prove what should be evident concerning bitrates and frame rates. Hey if you're happy with your methods, rock on. I'm just trying to encourage you to choose a frame rate for a reason rather than out of habit.

For one more example, our 100mbps 4k footage looks OK, but really the actual image is close to the quality of AVCHD. AVCHD is 28mbps at 1080p. Multiply that by 4 for UHD and you get a bitrate of 112mbps. To have the same quality (relatively) as the 50mbps 1080p30, the UHD would need to be 200mbps, like on the GH4.

It's just math. I'm not expressing an opinion here.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Here Chad, below video is a mixture of 1080p 50fps 28mbs avchd and 50mbs ipb mov and 100mbs 4K 25fps.

since you claim that 50fps looks like video and since there are plenty of shots in there that are either at 25fps and 50fps it should be easy for you to see the difference, no? Also, because math is all saying, could you also pick out a shot which is at 28mbs vs the 50mbs codec?

Re: FS5 - R U shooting 25/30p or 50/60p?
 

One more thought:

What is your timeline set to? If you shoot at 50p, but your timeline is at 25p, then the exported footage is going to look like you shot it at 25p, only the image quality takes a hit. In my example of 60p footage looking like video tape, that's only if your timeline and export settings are also 60p.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Here is a video that is both shot and delivered at 60p. Notice the glassiness?


Look at the playback settings in the lower right of the video.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

I edit in a 25p timeline, I"m also sure you cannot take out any shot out of my video that looks lower res because it's a 50fps to 25fps conversion, just like you cannot separate 25fps from 50fps.

My point is that shooting 50fps only has advantages once you deal with it in post, you can slow your footage down, you have much less judder while panning and you mix it with 25fps footage and no-one can tell the difference.

I"m sure if I pixel peep I can see differences, I"m not arguing that, but I see no reason not to shoot in 50P.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Another thing to note:

Vimeo does not play back videos at 60p or 50p. Vimeo is caped at 30p max. So if you upload a video at 50p, Vimeo throws away every other frame. So it's as if you shot at 25 or 30p, only your video takes a noise hit. In your wedding video I see noise in the shadows. If you shoot at 25p (and the proper shutter speed of 50) you are allowing more light to come into the camera, which means you can use less gain/iso and achieve the same exposure. Less gain means less noise, which usually shows in shadow areas. So the only reason to shoot at 50 or 60p is if you plan on slowing down the footage, like when the bride throws the bouquet. If you are editing at 25p, and do not plan on slowing down any footage, there is absolutely no benefit to shooting at 50 or 60p. I would shoot the ceremony at 25p (in my case 30p) and maybe the bouquet toss at 60p.

Try putting your camera up on a tripod in a low light situation, aiming at a wall with varying light levels. Shoot at 60p or 50p (with the appropriate shutter of 100 - 120) with a gain that that looks to be the right brightness. Now don't move the camera and shoot the wall again at 25p with a shutter of 50. Your wall is now over exposed, so turn your gain/iso down to get to the appropriate exposure level. Shoot a sample of that. Put both shots on a 25p timeline and look at the shadow areas at full screen. You undoubtedly see less noise in the footage shot at 50p.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

I export my videos in 25p as well to vimeo and the noise you see in my videos on vimeo are there in the native files, it's because I"m not shooting with a c100 or a7sII. :)


I shoot at 50fps at 1/50 shutter so the same amount of light comes in but with extra benefits, there is no light loss in this case and again, show me one shot in above video where shooting at 50fps and 1/50shutter would somehow be worse then 25fps and 1/50shutter because there are plenty of shots like that.


I never change framerates on the same camera at a wedding unless I absolutely have to, it only makes my job more difficult for no reason or benefit. If I would forget to change the framerate I might regret it later on if I want to slow footage down and it was shot at 25fps.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

I am not saying you are wrong, you are not, but all I am saying is that for me rules are there to be broken as long as it doesn't influence the end result in a way that a client might complain about it, it would take a trained eye and some pixelpeeping to see a difference from my way or the right way of working. I only see benefits by working the way I do and shooting in 50fps is one of them.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Maybe the OP Nigel Davey will absorb some of this knowledge and use it to get higher quality video out of his FS5.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Thanks Chad, I am indeed absorbing both arguments.

I also did some reading around this topic in other archive threads. For example whether the difference (in terms of data/information based on movement in the frame) between 50 fps is significantly less than that at 25 fps (where more movement has occurred)... and how this effects the compression/equation.

Quite honestly I'm not enough of an engineer to know the answer....even if I mostly understand the arguments.

So re 25p vs 50p I think I'll need to try some controlled filming using both options as well as a couple of real world projects and then compare the final output. My wife and son are very attuned to all things video, so I'll also get their input once I've completed this.

But of course the other key factor is how much extra work either version adds or removes in Post, particularly with grading. Again such tests will hopefully give me an answer.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

There is no increased workflow in post to deal with 25 or 50p, unless you have a very very old computer.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

An interesting variation on this theme is what's better for super slow motion? Obviously setting it to 60p over 30p and using the same fps setting will mean the playback is twice as quick. But is 60p the smoother and thus better overall option iro slow motion? Obviously the 'cinematic' look shouldn't be a factor here.

240fps at 60p would give you the same playback speed as 120fps at 30p. So provided you don't need anything below 25% slow motion (ie anything above 240fps incurs a lose of quality), then I assume 60p is the better way to go?

But you know what they say about 'assume'...

Re: FS5 - R U shooting 25/30p or 50/60p?
 

24P, 30P and 60i. The client dictates the frame rate.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Hmm, most of my clients wouldn't even know there was a frame rate.... they just want a video.

Must lure in more technical clients in the future;-)

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Assume:) we are talking about 240fps. On the Sony FS700 you can be shooting using 60p as your chosen setting but the minute you switch to 120 or 240fps or higher the camera defaults to 24p it will not stay in 60p.

Chris Young
CYV Productions
Sydney

Re: FS5 - R U shooting 25/30p or 50/60p?
 

To be honest Chris I'm not 100% sure about 240fps on the FS5 since I shoot in PAL. But since most of the users here (I assume) are Americas based I converted the numbers. But it works re the PAL equivalents on my FS5.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Same here Nigel we shoot in PAL. If I go to Super Slow 200fps the camera reverts from 50p to 25p though. If it doesn't do that on the FS5 then that is a BIG difference between and FS700's slo-mo and the FS5's. Interesting... will need to check this out.

Chris Young
CYV Productions
Sydney

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Just double checked and on my FS5 it is definitely showing (and I assume recording) 50p at 200fps in XACVHD at 50mbps.

When I get in the office I'll drop a test clip into Premiere and check the camera is not lying.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Yep, in Premiere it is showing the clip recorded as being 50p (when recorded in camera at 200fps 50p). However keep in mind that it will play back on the timeline twice as fast as if it had been recorded at 200fps in 25p.

Presumably if you only want to slomo something down to 25%, 200fps at 50p is the way to go.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

The math doesn't work that way for LongGOP encoding. Only the differences are recorded most of the time whether the frame rate is 30 or 60. Since the differences will be smaller at 60 and much larger at 30 the difference data for 60 will be less ( but twice as often ) as the bigger change needed at 30 and thus requiring more data to be recorded. Overall the data requirements I think are minimally different. The bigger difference is the processor is working hard to sample twice as fast for 60 compared to at 30. Likely why the FS5 will only do 30P in UHD compared to the FS7 etc.

An advantage of shooting at 60 with 1/60 shutter ( or 50 at 1/50 ) is that on a 60P ( 50P ) timeline the video will be smooth motion of video and on a 30P ( 25P ) timeline will be just the same as if it was shot at 30P ( 25P ). At least that is what happens in EDIUS.

Arguments may change for an iFrame encode but the FS5 is all LongGOP just like the X70 for example and closer to the consumer XAVC-S format but in a MXF wrapper.

Ron Evans

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Nigel if you have the time could you possibly run a 200fps clip through MediaInfo and see what it says? Just go to View and select Text and you will have the entire clip structure in front of you

https://mediaarea.net/en/MediaInfo

Only if you have the time as I'm curious.

I just checked the 700 again plus checked the footage on the timeline. The camera is definitely scanning at 200fps but it buffers it out and records it as 25p.

Chris Young
CYV Productions
Sydney

Re: FS5 - R U shooting 25/30p or 50/60p?
 

NICE work here Noa!

can I have a link for your vimeo ?

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Hi Chris I did what you asked with MediaInfo and the frame rate is definitely showing at 50fps for the 50p clip at 200fps. Likewise I also recorded a 25p 200fps clip and it shows as 25fps in MediaInfo.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Thanks for that Nigel. Just confirms my belief that the the overcrank settings although having the same fps available in the FS700 and FS5 are quite different as MediaInfo definitely states 25p for the 700 when running a 200fps.

Chris Young
CYV Productions
Sydney

Re: FS5 - R U shooting 25/30p or 50/60p?
 

The FS700 can record slow motion as either 25p or 50p (in PAL mode) - it is a menu setting.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

John - Really? I missed that one. Please shine the light for me and show me the error of my ways :)

Chris Young
CYV Productions
Sydney

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Got me hunting John.

Sorted it. So long since I've used the slo-mo I couldn't even remember where the menus was. Had to go back to the manual... when all else fails... page 52. I see now. If you set it to 25p in the Super Slow Motion menu at 200fps you actually get 12.5% slow and if you set it to 50p you actually get 25% slow motion. So it all depends just how slow you want it I guess. This camera was set to 25p so that's what threw me.

Thanks for pointing that out.

Chris Young
CYV Productions
Sydney.

Re: FS5 - R U shooting 25/30p or 50/60p?
 

Just thought I'd update folks over this. I wrote to Sony Prime Support and asked if the quality of 50P 50Mbps was degraded over 25P at 50Mbps in XAVC HD. I used the logic expressed further back in this thread, ie with a cap of 50Mbps and twice as many frames, 50P should have half the quailty compared to 25P which is getting the full 50Mbps. This is how Sony responded:

"That way of explaining would be correct in an Intra codec. However, since you record in XAVC Long GOP, there is no such "double quality" in a 25p frame compared to a 50p frame"

I'm afraid that's all I got back and I'm not technical enough to know why this is true.

Anyone else?

Re: FS5 - R U shooting 25/30p or 50/60p?
 

So no quality loss at all in (XAVC Long GOP) 50P compared to 25p? In that case I always would shoot in 50P.