Hi Peter,
You can change the video upload size limit in the Profile Type ACL settings(http://take.ms/M38Zf).
However, as stated in the setting, you have to make sure the upload_max_filesize is also set appropriately, which you have to consult your webhosting provider.

Thanks Raymond

if have set max.upload filez size to 300 MB. Some Videos in Equestrian Sports are a huge, e.g. a horse is jumping a full course. That takes at least 1 Minute. It´s not a movie but surely a short clip.

Now her is my Question.
I am the one who is currently uploading most videos and photos. But what happens to all the videos and photos? Will they be compressed in some way? That would be a huge amount of data in a short while otherwise?

Hey Peter,
You can find the uploaded videos in JoomlaFolder/media/com_easysocial/videos.
As for storage, it actually depends on how you want to go about it. Some people utilize cloud services like Amazon S3 to store their files and it has backup services as well. Some people upgrade their server disk space so that it can store more items. Different methods can have different costs as well so you have to do your research and consult these services to know more about your options.