The technologists complete a rigorous 2-yr program whereby they learn A&P, positioning for radiographs, physics of X-rays and radiation, and simple CNA-type skills. They take the X-rays ("plain" films), or go on to build on their Rad. Tech. skills to learn CT, MRI, Radiation Therapy, Cardiac Cath or Angiography, Mammography, Nuclear Medicine or Ultrasound. Their focus is on patient care as well, but from a different perspective (that of obtaining the images). I have known CT and Angio techs who are very savvy about VS and hemodynamics and patient care. However, they're not licensed as nurses but as technologists. For example, although our techs were trained in "tipping" the patients for a barium enema ("BE"), we nurses were occasionally called to "tip" the patient if the tech met resistance (not willful resistance, but physical resistance that impeded the process of placing the tip of the enema device into the rectum). I've known techs who were very skilled at starting IVs, whereas where I most recently worked, only the nurses started the IVs for out-patient contrast administration.
You might want to shadow a tech for a day or two, in different areas of the Imaging Department, to get a better idea of what the Techs and Nurses do. The Nursing duties vary from facility to facility, although for the most part they're responsible for Moderate Sedation administration and patient monitoring, during procedures (biopsies, angiograms, TIPS, myelograms, Nephrostomy tube placements, Ash-Split cath placement, other tunneled cath placements, PICC line placement under fluroscopy, Portacath placement, vascular embolization, etc etc).
Good luck in your search to find your niche.