diff --git a/csst_mci_sim/mci_data/mci_all_9K.config b/csst_mci_sim/mci_data/mci_all_9K.config
index 04b5ca410c6fa351beb747f55c25ba548c36f67a..06806bdc6b2576246ca257b012eb75d161e7728f 100755
--- a/csst_mci_sim/mci_data/mci_all_9K.config
+++ b/csst_mci_sim/mci_data/mci_all_9K.config
@@ -92,7 +92,7 @@ fullwellcapacity = 90000
 dark = 0.001
 
 #exposure to simulate, exposure time
-exptime = 300.0
+exptime = 100.0
 
 ###PNRU matrix sigma
 flatsigma=0.001