You mention using a visual radar. What do mean by that and how do you work it?
It is really very ease. All of us know how such a technique works.
An example: Many modern photo-related programs have, for instance, face detection. You feed the database with pictures of a face and the machine will be able to recognize the face in other pictures. You name that face. It is very handy if you want to search for a person in a large catalogue of images.
In photography the visual radar works the same way. Your mind is the program and that database that holds the data. Like a computer program you have to feed it. Feed it well, and it will serve you well. Feed it lousy, or not at all, and will serve you lousy. Or not at all.
When you study the photographs of famous photographers, or the paintings of celebrity painters, it is like feeding a machine with data.
It helps a lot if you know what you are doing. Roaming museums and photo books will not do it alone. You have to tell your mind what kind of mission you are on. You have to tell it that you are on a data collection mission. You could say for instance: we are here to study the use of light and composition. Whatever you decide. That, then, is what you have to set your mind up to.
Study a limited number of objects at a time. Maybe even only one single picture to begin with. Later you can go for more advanced stuff like a photographers style, his use of people and spaces. His uses of lights and shadows. Et cetera, et cetera. Soon you will walk down your own alley.
Try to remember what you see. Having HCB as a mentor it is clearly HCB’s photos you want to study. When you have collected enough data you are ready to go to work. In the city, if you are street photographer. In the countryside, if that is what you prefer.
And again, if you just roam around mindlessly you get nothing out of it. Being out there you have to turn on the radar. Let it know that you intend to use it. Let is scan the surroundings for you. The streets, the cafés and the parks. The people passing. When something interesting comes along the radar will stop you. Ask you to take that picture.
You will be surprised how well such a radar will serve you once you have discovered that you have one. And you have set it to use.
That is what the radar is, and how you use it.