diff --git a/catalog/C9_Catalog.py b/catalog/C9_Catalog.py
index 7081abcd65972d69301f6faa70b750b3a1fa54d9..8dc629fe6bf4414e3266c861b0a9d619d7a89c3c 100644
--- a/catalog/C9_Catalog.py
+++ b/catalog/C9_Catalog.py
@@ -468,6 +468,10 @@ class Catalog(CatalogBase):
                                                         0., 0., 0., 0., 0., 0., 0., 0., 0., -1, 0.)
 
             self.objs.append(obj)
+    
+    def free_mem(self, **kward):
+        self.starDDL.freeGlobeData()
+        del self.starDLL
 
     def _load(self, **kwargs):
         self.objs = []
diff --git a/observation_sim/instruments/chip/effects.py b/observation_sim/instruments/chip/effects.py
index 7c4c7dcc81d57b332c1d6bed124488f2d41ac717..0f835d2262e8d7042bc0160c22a860cf92a9b4a9 100644
--- a/observation_sim/instruments/chip/effects.py
+++ b/observation_sim/instruments/chip/effects.py
@@ -84,7 +84,7 @@ def BadColumns(GSImage, seed=20240309, chipid=1, logger=None):
     rgdn = Generator(PCG64(int(seed*1.3)))
 
     nbadsecA, nbadsecD = rgn.integers(low=1, high=5, size=2)
-    collen = rgcollen.integers(low=int(ysize*0.1), high=int(ysize*0.7), size=(nbadsecA+nbadsecD))
+    collen = rgcollen.integers(low=int(ysize*0.1), high=int(ysize*0.5), size=(nbadsecA+nbadsecD))
     xposit = rgxpos.integers(low=int(xsize*0.05), high=int(xsize*0.95), size=(nbadsecA+nbadsecD))
     if logger is not None:
         logger.info(xposit+1)
@@ -350,8 +350,12 @@ def MakeTrail(imgarr, satuyxtuple, charge, fullwell=9e4, direction='up', trailcu
                 imgarr[yi, xi] = fullwell
                 if direction == 'up':
                     yi -= 1
+                    if yi == (imgarr.shape[0]//2 - 1):
+                        break
                 elif direction == 'down':
                     yi += 1
+                    if yi == (imgarr.shape[0]//2):
+                        break
                 yy += 1
             else:
                 if trail_frac < trailcutfrac:
@@ -363,8 +367,12 @@ def MakeTrail(imgarr, satuyxtuple, charge, fullwell=9e4, direction='up', trailcu
 
                 if direction == 'up':
                     yi -= 1
+                    if yi == (imgarr.shape[0]//2 - 1):
+                        break
                 elif direction == 'down':
                     yi += 1
+                    if yi == (imgarr.shape[0]//2):
+                        break
                 yy += 1
 
     return imgarr
diff --git a/observation_sim/mock_objects/CatalogBase.py b/observation_sim/mock_objects/CatalogBase.py
index 106e4e751d2ca2ac0ba5d9f1118991bd734cd0de..ea94b775dcf16dd7368332bd4e2459cb2dd5a8ff 100644
--- a/observation_sim/mock_objects/CatalogBase.py
+++ b/observation_sim/mock_objects/CatalogBase.py
@@ -12,6 +12,9 @@ class CatalogBase(metaclass=ABCMeta):
     def __init__(self):
         pass
 
+    def free_mem(self, **kward):
+        pass
+
     @abstractmethod
     def load_sed(self, obj, **kward):
         pass
diff --git a/observation_sim/sim_steps/add_objects.py b/observation_sim/sim_steps/add_objects.py
index 81cb5892128f0be3870d57089b2949b1de4485a1..b35325b28889be3c3c695fbad693aad9229c0586 100644
--- a/observation_sim/sim_steps/add_objects.py
+++ b/observation_sim/sim_steps/add_objects.py
@@ -102,6 +102,7 @@ def add_objects(self, chip, filt, tel, pointing, catalog, obs_param):
         # # [DEBUG] [TODO]
         # if j >= 10:
         #     break
+        
         obj = cat.objs[j]
 
         if not self._is_obj_valid(obj):
@@ -133,7 +134,6 @@ def add_objects(self, chip, filt, tel, pointing, catalog, obs_param):
             continue
 
         # [TODO] Testing
-        # print(obj.param["mag_%s" % filt.filter_type.lower()], obj.param["mag_%s" % cut_filter.filter_type.lower()])
         # self.chip_output.Log_info("mag_%s = %.3f"%(filt.filter_type.lower(), obj.param["mag_%s"%filt.filter_type.lower()]))
 
         # Exclude very bright/dim objects (for now)
@@ -242,8 +242,8 @@ def add_objects(self, chip, filt, tel, pointing, catalog, obs_param):
         obj.unload_SED()
         del obj
         # gc.collect()
-    cat.starDDL.freeGlobeData()
-    del cat.starDDL
+    cat.free_mem
+    del cat
 
     if chip.survey_type == "spectroscopic" and not self.overall_config["run_option"]["out_cat_only"] and chip.slsPSFOptim:
         # from observation_sim.instruments.chip import chip_utils as chip_utils