Photometry of the Other Program Frames

The procedure described above is the standard procedure and results in an independent reduction of each frame. However, there are cases where a different approach is more efficient. Imagine, for instance, that several frames of the same region in the sky had to be reduced but the frames were taken in different seeing conditions, or at telescopes with different pixel matching. It is useful, in this case, to transfer the inputs from the frame with the best resolution to the others. The result of this operation is to add information (number of components, for instance) to the frames of poor quality. This procedures obviously applies also to frames taken with different filters.

The operation requires three logical steps:

1.

Create a base for transformation of coordinates from frame A to frame B;

2.

Transform the coordinates from A to B;

3.

Adjust the input (intensity, background, holes and so forth)

These steps are accomplished by the commands CBASE/ROMAFOT, CTRANS/ROMAFOT and ADAPT/ROMAFOT, respectively.