I've done several time lapse videos with my A7, both with the Play Memories app and using external software.
The PM app works quite fine and will give decent time lapse footage. But it's very basic, and won't allow much user input with regards to pre or post production settings. It just spits out the final movie. If, for example, you are doing moving clouds over trees, you are bound to see a perfectly exposed sky and clouds over dark silhouetted tree shapes. There is no way to balance the images by bumping up shadow detail.
Nowadays I only use the PM app to capture the images (it has that setting) and export them to LRTimlapse:
LRTimelapse - advanced Time Lapse Photography made easy!
This are online video tutorials, very easy to learn and the app is painfully easy to use. There is a very usable free version - the pro versions adds some things that only a professional would need.
The "LR" in the title stands for "Lightroom", it does need to use Lightroom's powerful image management facilities. But you will have complete control of the final product. It's especially useful with changing lighting conditions, and will also allow for virtual camera pans and zooms, making the video much more interesting.
My iMac is in the shop ATM. When I get it back I'll try and remember to post an example TL video.
