First time tomato grower - please help!

helen.connolly94XpxtBPAG

Hi all. This is my first year growing tomatoes. Some plants seem healthy but others have started to look sick - the leaves are turning pale and dry as shown in the pictures. I’ve been told to water “little and often” so I’m giving them a quick shower at the base (avoiding leaves) every 1-2 days and feeding with tomato feed once a week. Could it be an issue with watering or something more sinister? TIA! 

Fairygirl

Little and often is actually the worst way to water. Water them thoroughly, then leave them until they're slightly droopy before watering again. That encourages the roots to stay down,  rather than near the surface, and makes them more stable.  
If they're outdoors, you have to be guided more by the general weather conditions, so don't keep watering when it isn't necessary. They won't appreciate sitting in wet soil all the time. That's when it's important for them to have good drainage whether in pots or in the ground. 
No need for food until fruits start to set. 
The leaf damage is nothing to worry about. Perfectly normal. Sun/wind can cause it, but older foliage at the bottom will die off anyway as the plants grow. 

helen.connolly94XpxtBPAG

Thank you for the advice @Fairygirl
Noted about the watering/feeding. I am a bit concerned that it is affecting some of the top leaves on a couple of the plants, and the affected plants look a lot shorter/less full than the others. I’ll see how they get on with watering less frequently