Photometrica - Instant photometry of remote telescope CCD images

Step 3: Stacking images

We have now checked that the V Cnc images looks OK, and next we would like to stack them. First select the images by checking the check boxes in the left-most column:

Figure 1: Select the images

Then, click the 'Stack (add)' link above the list:

Figure 2: Stacking the images

This will coadd the images. It uses the WCS information to align the images, and then average them. Note that in this version of Photometrica stacking only works when there is no rotation. It will NOT work if there is a meridian flip in the sequence of images. This will be improved in a later version.

After the images has been stacked the list looks like this:

Figure 3: List with stacked image (click for larger image)

Note that the stacked image is shown in bold. Also, it is placed between the two single exposures since the list is sorted by observation date/time, and the date/time of the stacked image is the average of the mid-point of the single images.

You can of course stack as many images as you like.

Next: Measuring Stars Manually