File size is too large when shared as mp4 video

I have created a 5min slideshow with photos and a sound track that contains both music and voice narration. I want to enter this programme into a competition that requires all programmes to be played on Windows. This means sharing the programme to mp4 video. But one of the other requirements is that the total file size is no more than 500MB. When shared as mp4 my file size is just under 800MB. I have tried down sizing the images but that appears to have no effect.

Any suggestions about how to solve this please.
If it not possible to solve it I would like to know so I can contact the organisers.

@Trixpics The size of the images doesn’t matter because the size of the video depends on the video resolution and frame rate. You could try to export a lower resolution video or choose a lower frame rate (25 or 30 frames should be great).

The size of an MP4 also greatly depends on the compression. You can try to reduce the Bitrate while exporting:

Many thanks for your reply. I am still working on it.
These AVs will be played on a data projector in a large auditorium so I am concerned to maintain as much quality as possible. I do not understand about bitrate and how to change that without unduly affecting the quality of the AV. I see it is set to auto and 8000. I also understand how I can change it. What I don’t understand is the effect of changing it and how much it is reasonable to change it by.

I have spent most of the day working out this issue and I think I understand it now. There is no set bitrate but I need to choose one which gives the largest allowable file - in this case it has to be under 500MB. Next time there may be different requirements. Finally check to ensure that the slideshow still plays smoothly.

Many thanks for setting me searching in the right


maybe it is related to your projector. I have a sony 4k projector and once I got the similar situation like you, and I contacted with the manufacture then I adjusted the size of projector. Alternatively you can also refer to some guides of projectors, such as the one I referred to before buying so I know the basic features and warranty of projector.