diff --git a/kstars/fitsviewer/fitsview.cpp b/kstars/fitsviewer/fitsview.cpp
--- a/kstars/fitsviewer/fitsview.cpp
+++ b/kstars/fitsviewer/fitsview.cpp
@@ -1547,17 +1547,16 @@
 
 void FITSView::initDisplayImage()
 {
-    if (!rawImage.isNull() &&
-            rawImage.width() == imageData->width() &&
-            rawImage.height() == imageData->height() &&
-            (((rawImage.format() == QImage::Format_Indexed8) && (imageData->channels() == 1)) ||
-             ((rawImage.format() == QImage::Format_RGB32) && (imageData->channels() == 3))))
-        return;
-
     // Account for leftover when sampling. Thus a 5-wide image sampled by 2
     // would result in a width of 3 (samples 0, 2 and 4).
     int w = (imageData->width() + sampling - 1) / sampling;
     int h = (imageData->height() + sampling - 1) / sampling;
+
+    if (!rawImage.isNull() && rawImage.width() == w && rawImage.height() == h &&
+            (((rawImage.format() == QImage::Format_Indexed8) && (imageData->channels() == 1)) ||
+             ((rawImage.format() == QImage::Format_RGB32) && (imageData->channels() == 3))))
+      return;
+
     if (imageData->channels() == 1)
     {
         rawImage = QImage(w, h, QImage::Format_Indexed8);