Fig. 3 Fig. 4
It is rewarding to see that the distributions of stars and galaxies are quite different - as was expected. It gives us some confidence that the tricky process of star/galaxy separation works well. Visual checks of the J-data suggest that the automatic star/galaxy separation yields errors smaller than 10 %.
An automized comparison of the data from the R-plates with those from the J-plates has the advantage that the classification of all objects can be checked, something which is not possible visually. Although the quality of the procedures is not tested by this comparison, the reliability with which the chosen routines work on the same object at different brightness levels and on plates taken under different observing conditions will be given. Another test is the comparison between automatically determined morphological types of galaxies on R- and J-plates. Its outcome will be more difficult to interpret because physical effects will also play a role. It will be interesting to see whether a colour dependence of morphological classification can be quantified.