The full specification details of the D415 and D435 cameras can be found in their data sheet document.
Looking over the sheet, it seems that the wide mode is limited to the infrared sensor and stereo sensors, and that the RGB sensor does not have a wide field.
Calibration of the 400 Series cameras can be performed with a calibrator tool.
To add to what Marty already posted
(1) Regarding FOV
(a) Color FOV of D415, and Color FOV of D435 is identical: Diagonal 77.
(b) Depth FOV of D415 is Diagonal 70 [IR cameras have FOV 77, but while aligning images from 2 IR sensors for computing Depth some areas are probably cropped].
(c) Depth FOV of D435 is Diagonal 90 [IR camera have FOV 100.6, but again cropping while computing depth]
Above are the max FOV numbers. So on D435 you can get Depth FOV less than FOV but not higher.
Similarly for D435 RGB camera, max FOV is 77, you can't get beyond that.
(2) What kind of calibration are you looking for? Note that librealsense already has calibration data, and you should be able to use it via realsense APIs. You can obtain
(a) Intrinsic calibration matrices for each camera
(b) extrinsic calibration from one sensor frame to another sensor frame
This link has some good details regarding camera calibration