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Refresh rate with PAL footage
Posted: Tue May 08, 2018 17:00
by insch
I'm prepping 25 fps PAL sequences for live performances. I need to be able to reliablly monitor the video output from my MacBook Pro to check all is well before the night. The monitor I bought a few months ago for this purpose (Samsung UE590D 28" Ultra HD 4K) is locked to a refresh rate of 60 Hz which can only be changed through FreeSync which the graphics card on my MacBook Pro does not support. It offers no manual control of refresh rate. This setup seems pretty standard across different brands and monitors. 60 Hz is not great for 25 fps footage.
There was definitely a difference between the smoothness of the output when playing on this monitor and playing on my Sony TV (using same laptop output and adapter) which I could sync to 50 Hz through Mac Settings. Unfortunately it is too late to return this Samsung monitor but I am prepared to sell it and buy a new one that will be more fit for my requirements. However I am at a loss to find any 28” 4K monitor that will allow me to sync at 50 Hz. They all seem to be 60Hz or above and only work with auto sync options. When I ask about syncing for 25 fps footage sellers generally reply with ‘that’s the first time I’ve been asked that’.
What is everyone else using to test playback in the PAL world? Should I look for a TV rather than a computer monitor? I don’t have to have absolute top notch picture quality (I trust that bit) but I need to have stable playback (I am more nervous about that).
Thank you

Re: Refresh rate with PAL footage
Posted: Wed May 09, 2018 02:11
by drazkers
insch wrote:I'm prepping 25 fps PAL sequences for live performances. I need to be able to reliablly monitor the video output from my MacBook Pro to check all is well before the night. The monitor I bought a few months ago for this purpose (Samsung UE590D 28" Ultra HD 4K) is locked to a refresh rate of 60 Hz which can only be changed through FreeSync which the graphics card on my MacBook Pro does not support. It offers no manual control of refresh rate. This setup seems pretty standard across different brands and monitors. 60 Hz is not great for 25 fps footage.
There was definitely a difference between the smoothness of the output when playing on this monitor and playing on my Sony TV (using same laptop output and adapter) which I could sync to 50 Hz through Mac Settings. Unfortunately it is too late to return this Samsung monitor but I am prepared to sell it and buy a new one that will be more fit for my requirements. However I am at a loss to find any 28” 4K monitor that will allow me to sync at 50 Hz. They all seem to be 60Hz or above and only work with auto sync options. When I ask about syncing for 25 fps footage sellers generally reply with ‘that’s the first time I’ve been asked that’.
What is everyone else using to test playback in the PAL world? Should I look for a TV rather than a computer monitor? I don’t have to have absolute top notch picture quality (I trust that bit) but I need to have stable playback (I am more nervous about that).
Thank you

After looking at the manual there is an option on the monitors menu to disable freesync. From there you should be able to force a frequency of 50hz.
Re: Refresh rate with PAL footage
Posted: Wed May 09, 2018 12:03
by Zoltán
Resolume will lock the maximum frame rate to the slowest refresh rate display you connect to it.
You can also force the Resolume rendering frame rate to a maximum by setting the frame rate in Composition settings.
Having said that this doesn't affect your monitor's refresh rate.
You might be able to force the monitor to 50Hz (or 75@1080p) using
SwitchResX.
What does your final setup look like for which you are checking your footage, is it also a 25/50 Hz output?
Re: Refresh rate with PAL footage
Posted: Wed May 09, 2018 12:33
by insch
drazkers wrote:insch wrote:I'm prepping 25 fps PAL sequences for live performances. I need to be able to reliablly monitor the video output from my MacBook Pro to check all is well before the night. The monitor I bought a few months ago for this purpose (Samsung UE590D 28" Ultra HD 4K) is locked to a refresh rate of 60 Hz which can only be changed through FreeSync which the graphics card on my MacBook Pro does not support. It offers no manual control of refresh rate. This setup seems pretty standard across different brands and monitors. 60 Hz is not great for 25 fps footage.
There was definitely a difference between the smoothness of the output when playing on this monitor and playing on my Sony TV (using same laptop output and adapter) which I could sync to 50 Hz through Mac Settings. Unfortunately it is too late to return this Samsung monitor but I am prepared to sell it and buy a new one that will be more fit for my requirements. However I am at a loss to find any 28” 4K monitor that will allow me to sync at 50 Hz. They all seem to be 60Hz or above and only work with auto sync options. When I ask about syncing for 25 fps footage sellers generally reply with ‘that’s the first time I’ve been asked that’.
What is everyone else using to test playback in the PAL world? Should I look for a TV rather than a computer monitor? I don’t have to have absolute top notch picture quality (I trust that bit) but I need to have stable playback (I am more nervous about that).
Thank you

After looking at the manual there is an option on the monitors menu to disable freesync. From there you should be able to force a frequency of 50hz.
I saw that option but unfortunately it is greyed out so this monitor seems fixed at 60Hz. I am exploring another solution where I work with this little device
https://cvp.com/product/blackmagic_bmd-bdlkulsdzminimon which gives a true video output from the laptop (as opposed to desktop out), maybe giving me more stability all round, and then getting rid of my Samsung monitor and buying a small HD TV instead. Image quality isn't crucial in this process since I'm more confident about that but the TV would show me whether playback was stable or not.
Re: Refresh rate with PAL footage
Posted: Wed May 09, 2018 12:49
by insch
Zoltán wrote:Resolume will lock the maximum frame rate to the slowest refresh rate display you connect to it.
You can also force the Resolume rendering frame rate to a maximum by setting the frame rate in Composition settings.
Having said that this doesn't affect your monitor's refresh rate.
You might be able to force the monitor to 50Hz (or 75@1080p) using
SwitchResX.
What does your final setup look like for which you are checking your footage, is it also a 25/50 Hz output?
Thanks. SwitchResX looks interesting - worth a try before heading to EBay to sell this monitor. It is crucial that I get it to lock to 50Hz. My footage is DXV 25 fps but not sure where I would check for the Hz setting of my laptop output? Ultimately I have had some inconsistent (sticky) playback issues of my DXV footage in Resolume and need to establish a stable playback setup from my laptop to see what it's really outputting.
Re: Refresh rate with PAL footage
Posted: Wed May 09, 2018 14:48
by insch
So far so good with SwitchResX. I installed it, selected my monitor and set the current resolution to 1080p25 (PAL) (It was defaulting to 1080p30 (NTSC)) and the playback now seems stable. I had no idea that there was a bit of software out there that would do this. I can't see how to double check that the monitor is now actually at 50 Hz refresh rate but the imagery is good so far.
Thank you!

Re: Refresh rate with PAL footage
Posted: Wed May 09, 2018 15:24
by Zoltán
sounds great!
if you select 25p then the monitor will run at 25Hz.
You can double check this in Resolume, enable Show fps in the output menu.
and when you output to this display the maximum fps you see should be 25 with the composition fps set to auto.
Re: Refresh rate with PAL footage
Posted: Wed May 09, 2018 15:39
by Oaktown
It the refresh rate is crucial, I would personally buy a
Decimator MD-HX and put it between the server and the display. It's a small investment (~US$300) but you will never regret having it in your toolkit!
Re: Refresh rate with PAL footage
Posted: Wed May 09, 2018 16:54
by insch
Zoltán wrote:sounds great!
if you select 25p then the monitor will run at 25Hz.
You can double check this in Resolume, enable Show fps in the output menu.
and when you output to this display the maximum fps you see should be 25 with the composition fps set to auto.
Thank you Zoltan
I did find the menu showing the refresh rate on the monitor and it said 25 Hz so all good there. Where can I check that the composition fps is set to auto?
Re: Refresh rate with PAL footage
Posted: Wed May 09, 2018 16:56
by insch
Oaktown wrote:It the refresh rate is crucial, I would personally buy a
Decimator MD-HX and put it between the server and the display. It's a small investment (~US$300) but you will never regret having it in your toolkit!
Will check this out. Thank you. It doesn't seem to have a Thunderbolt input so I guess I would still need a Thunderbolt to HDMI adapter in place?