diff --git a/src/MainUI.gd b/src/MainUI.gd
index 3777edf..f2c817c 100644
--- a/src/MainUI.gd
+++ b/src/MainUI.gd
@@ -41,13 +41,13 @@ func _input(event):
 #
 
 func set_buttons_disabled(disabled: bool):
-	if disabled:
-		for b in [open_shader_button, open_image_button, save_image_button, fit_image_button, apply_shader_button, status_indicator]:
-			b.disabled = disabled
+	var btns = []
+	if disabled or (Filesystem.input_image_path != "" and Filesystem.shader_path != ""):
+		btns = [open_shader_button, open_image_button, save_image_button, fit_image_button, apply_shader_button, status_indicator]
 	else:
-		for b in [open_shader_button, open_image_button, fit_image_button, apply_shader_button, status_indicator]:
-			b.disabled = disabled
-
+		btns = [open_shader_button, open_image_button, fit_image_button, apply_shader_button, status_indicator]
+	for b in btns:
+		b.disabled = disabled
 #
 
 func _on_open_shader_button_pressed():