diff --git a/PITtrack2.m b/PITtrack2.m
index f36de95..6b07b88 100644
--- a/PITtrack2.m
+++ b/PITtrack2.m
@@ -72,8 +72,11 @@ function PITtrack2(site,C)
         placedData(nf).Sdist = Sdist;
         placedData(nf).Ndist = Ndist;
     end
+elseif ~isfield(placedData,'Ndist')
+    for nf = 1:nftot
+        placedData(nf).Ndist = NaN;
+    end
 end
-
 % use taglist to cut labData to only the requested particles
 if ~isempty(taglist)
     % shorten the labdata to only the requested tags
@@ -237,4 +240,4 @@ function PITtrack2(site,C)
     eval([datee,' = data(:,',num2str(n),');']);
     evalstr = [evalstr,',',datee];
 end
-eval(['T = table(',evalstr,');']);
\ No newline at end of file
+eval(['T = table(',evalstr,');']);
diff --git a/PITtrack_default.m b/PITtrack_default.m
index 69e2c3d..42faf30 100644
--- a/PITtrack_default.m
+++ b/PITtrack_default.m
@@ -9,16 +9,10 @@
 % site 2 = Ganny = 0; % Wilket Creek (Papangelakis et al 2019)
 
 if site == 1
-    % for Bradley
-    def_data.D50 = 55; % mm
-    def_data.szcat = 2.^[5:1:6];
-    def_data.fdir = 'F:\Research\Publications\In Preparation\2020 Elli Nature Geoscience\Bradley 2017 data\tagged\';
-    def_data.fchar = 'Tag Characteristics Halfmoon.csv';
-elseif site == 2
     def_data.D50 = 37; % mm
-    def_data.szcat = 2.^[5:1:8];
-    def_data.fdir = 'F:\Research\Publications\In Preparation\2020 Elli Nature Geoscience\Elli Thesis Data\Ganny\';
-    def_data.fchar = 'Tag Characteristics 2.csv';
-    def_data.thalname = 'GCrk_Thalweg_rev.csv';
-    def_data.taglist = 'DS_Ganny_tagnum.csv';
-end
\ No newline at end of file
+    def_data.szcat = 2.^[5:1:8]; % size categories in -phi values (log base 2 classification system)
+    def_data.fdir = 'Ganatsekaigon\'; % directory path
+    def_data.fchar = 'Tag Characteristics 2.csv'; % name of file that contains tracer characteristics such as sizes
+    def_data.thalname = 'GCrk_Thalweg_rev.csv'; % name of file that has the thalweg data
+    def_data.taglist = 'DS_Ganny_tagnum.csv'; % list of tag numbers to include in analysis (may be a subset of all tags in river)
+end