[enyafriend]

Sorry for this late reply.

To your question, yup, it's an all day thing. Many people will be coming in and out of the temples throughout the day. Best time, I think, will be in the morning.

If you wanna take pics, if you're standing at a distance, you can take the pics and no one will notice you. But if you really want to take close-up pics of someone praying, it's best you ask for permission first. Some might oblige you while others might object to it.
Feel free to ask anyone that you fancy to have a pic with you. I think many people won't mind that.

If you are watching over your wallet, then you may want to buy your meals off covenience stores, where they sell a variety of lunch boxes at very reasonable prices.

Have fun.