LOL, when you click DDNS, the camera has a drop down menu. I'm asking you what choices do you have when you view them. Each camera gives you different choices.
Maybe you don't have the camera yet? It is likely that the ones Vec pictured are the same for the camera you're considering, but I don't know for sure.
Not to sound rude or anything, but do you have the camera? Did you look at the list of choices? Did you even look at the picture I posted? If you did, than you would see the last choice of update period and that would have answered your question.
It's not really a good idea to have a camera update DDNS. See what your router supports, that's the best place to update DDNS because without the router, you have no internet access anyway and cameras come and go, so you would not want to lose access to all your cameras because the one updating DDNS is down. Also, only one DDNS updater should be running on your network, not every camera.
Mine at home only has the paid ddns and the firmware is updated. I have the application for NOIP that keeps the ip updated about every 4min. Then again, my ip doesn't change very often.
Alot of times if the camera I'm using only has paid choices, than where you fill in the server IP, I enter nvrdns.com or easterndns.com, or a free ddns server. If the drop down says dyndns, and dyndns wants you to pay, just choose dyndns and than in the server IP address, enter nvrdns.com. It will go to the server IP address rather than the drop down choice. Also, if you have an NVR, use the NVR to update your IP, not the cameras, as mentioned.