International standards

To clarify when mentioning 24-25p conversion I was thinking to actually change the speed by a few % which might be better than making a load of interpolated frames.

easy in resolve, export project at 24p "my_film_24p", new project project settings 25p, import "my_film_24p", clip attributes change to 25p, add to timeline, export new timeline as "my_film_25p"
duration will have changed, no frame interpolation.

to make 'myfilm_30p' frame interpolation will be needed, resolve 'optical flow' probably do a good job of this.

turn up with a 24p 25p and 30p files and you will be golden??

Clearly playing the 24p on is ideal if it works.

S
 
CharlesPapert said:
thanks jmone. Appreciate your chiming in. I'm a little confused however because it sounds like you are saying don't worry, the laptop will do the necessary conversion, but then you also suggest that certain frame rates will result in either a speed change or dropped frames. If it's really going to save him any issues, it seems like it would be better to convert the material to something that is more directly compatible with 50hz while still here, or at least have both versions with him so he can see which plays best?
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I must be explaining it incorrectly. 50hz is a broadcast standard... but, who cares, as you are not broadcasting.

A Laptop/PJ is not limited to a single frequency, and it should support all the major frequencies (but he needs to check). If he changes the refresh rate to that of what you produce, the laptop/PJ will not be converting anything, as the refresh rate will match the frame rate. See the attached pic from my Windows PC. As you can see, I can select all the major refresh rates for my display. So if you sent me a 24fps, I'd select 24hz. If you sent me 60fps I'd select 60hz and have no dropped or repeated frames. There is no conversion required when you change the refresh rate of your display to match (or a clean multiple) of the FPS of the content.

He will need to check but it would be unlikely that this list would be any different. All he has to do it select the refresh rate to match what you render (which should also be what you captured).

Can I ask what the FPS is of the original clips you recorded at?
 

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To clarify, the digital DVB-T standard is 50fps for broadcast TV (not 25 / 50i as was in analog). So there are two basic choices for content shot at 24fps that needs to be broadcast over 50hz DVB-T:
- Speed Up & Audio Pitch Correction: Each frame is doubled, the timeline is speed up by 4% and a Audio Pitch Correction is done.
- Frame Repeats: Double the frame to 48fps, and repeated a single frame each 1/2 sec to get to 50fps

This is ONLY for Broadcast. When playing media directly we can pick a display rate to match that of the media's fps.

Please note that as Non-NTSC users we are pretty susceptible to seeing frame drops/repeats from poorly presented video - you want to get this right or it will look like amateur hour.

As a general Jib (please take it the right way)... Thankfully most of the world is not the basket case that is NTSC.
world_map_lg_ntsc-768x369.png

It's bit like metric. One day it will make sense :) ...and Myanmar is going Metric. So that leaves?

2f64bdc2d0842cf3b95637d35e7208dd.jpg
 
You are not wrong but sometimes use words such as 'should'.

In professional delivery 'should' is not a word.. only 'does'

98% chance it will just work but 2% it wont

but we are not talking (afaik) just a laptop - but a lattop to a screen. it is the second element than might not work

on that basis I feel that pre preperation of a few files would be very safe and not rely on any in country technology.
 
I completely agree. I thought that that I had made it clear that while it should work, it needs to be tested on the actual equipment that is going to be used. And I mean everything including the actual video that is going to be played. No one wants to sit there while some boffin twiddles knobs.
 
CharlesPapert said:
by Redbyte box do you mean a Decimator, or a Decimator MD-HX or Cross? The Decimator doesn't do any format conversion per se, other than HDMI type. If it was psf to p or format conversion it would have been an MD-HX or MD-Cross.
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Maybe we’re talking about something different, but I’m pretty sure that all of my Decimators(Quad, MD-DUCC, DMON 6S) allow conversion of the output signal (SDI and HDMI) to pretty much any standard SD or HD resolution and frame rate, including p, i and PsF variations.

Also…. I’ve been trying to get my hands on one of the new 12G Cross units for a while, but Decimators, with the exception of one or two models, have been on back-order/extremely limited availability since Covid. I checked again on B&H last week and pretty much everything, except one or two models, is listed as back-order or unavailable (or some variant of the theme…). I was on an engineering board recently, too, and someone said they just got a couple that they ordered ~15 months ago.
 
Run&Gun said:
Maybe we’re talking about something different, but I’m pretty sure that all of my Decimators(Quad, MD-DUCC, DMON 6S) allow conversion of the output signal (SDI and HDMI) to pretty much any standard SD or HD resolution and frame rate, including p, i and PsF variations.

Also…. I’ve been trying to get my hands on one of the new 12G Cross units for a while, but Decimators, with the exception of one or two models, have been on back-order/extremely limited availability since Covid. I checked again on B&H last week and pretty much everything, except one or two models, is listed as back-order or unavailable (or some variant of the theme…). I was on an engineering board recently, too, and someone said they just got a couple that they ordered ~15 months ago.
Click to expand...

Yes, that's indeed true, many of the other modern Decimators perform scaling, in general terms if it has the red plastic case and front panel buttons vs the red metal casebuttons it contains a scaler. So it could have been one of the other "new" boxes in use. But the older ones including both versions of Decimator (the downconverter model, currently called Decimator 2) that do not scale, they just offer a downconverted analog SD signal from SDI.

Shame to hear they are having trouble getting back on their feet. I haven't bought anything from them since before pandemic. I was one of their early dealers but when they lost their US distributor it became unfeasible (dealers have to order through their UK distributor now).
 
I talked to my friend today, he is going to send test clips over to be tested on the system in Amsterdam (and they seem to be a variety of frame rates). I suggested to him that not only do they need to be checked for simply an image, the motion cadence should be looked at carefully, even more important as they are Steadicam demo clips and motion issues could be a real issue if there is dodgy conversion going on. He said the contact there is a cinematography professor so he should know what to look for. I said "maybe--or maybe not".
 
Sounds good.

Having multiple fps clips can make it more challenging. The main thing he should get them to check, is how long it takes their system to change refresh rates between clips as this can be slow on many projectors (one of mine takes 15sec). This gap then needs to be taken into account if they plan is to play one clip directly after another (say in a playlist). The impact is (even with the playback SW doing the auto refresh rate changing) the next clip will start playing but you will miss the first X-Seconds required for the PJ to resync to the new frequency (all the time the audio will be playing as well).
 
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