g_signal_connect (scd->spin_sample_size, "value-changed", G_CALLBACK (sample_consistent), scd);
g_signal_connect (scd->spin_sample_limit, "value-changed", G_CALLBACK (sample_consistent), scd);
g_signal_connect (scd->spin_sample_size, "value-changed", G_CALLBACK (sample_consistent), scd);
g_signal_connect (scd->spin_sample_limit, "value-changed", G_CALLBACK (sample_consistent), scd);