diff --git a/core/src/controller.rs b/core/src/controller.rs
index 5c2c594b..ab7f9df0 100644
--- a/core/src/controller.rs
+++ b/core/src/controller.rs
@@ -6,7 +6,6 @@ use crate::preview;
 use crate::repo;
 use crate::scanner;
 use crate::Result;
-use std::path;
 
 /// Aggregate API for the scanner and the repository.
 #[derive(Debug)]
@@ -33,17 +32,41 @@ impl Controller {
         Ok(())
     }
 
+    // Gets all photos that have a preview
+    // TODO make a database query for this instead of filtering
+    pub fn all_with_previews(&self) -> Result<Vec<repo::Picture>> {
+        let pics = self.repo.all()?;
+        let pics = pics
+            .into_iter()
+            .filter(|p| p.square_preview_path.is_some())
+            .collect();
+        Ok(pics)
+    }
+
     /// Gets all photos.
     pub fn all(&self) -> Result<Vec<repo::Picture>> {
         self.repo.all()
     }
 
-    pub fn add_preview(&mut self, pic: &mut repo::Picture) -> Result<path::PathBuf> {
-        let preview = self.prev.from_picture(pic.picture_id.id(), &pic.path);
-        if let Ok(ref path) = preview {
-            pic.square_preview_path = Some(path.clone());
-            self.repo.add_preview(pic)?;
+    pub fn update_previews(&mut self) -> Result<()> {
+        // TODO make a database query to get pictures
+        // that need a preview to be computed
+        let pics = self.repo.all()?;
+        let pics = pics
+            .into_iter()
+            .filter(|p| p.square_preview_path.is_none())
+            .collect::<Vec<repo::Picture>>();
+
+        for mut pic in pics {
+            self.prev.set_preview(&mut pic)?;
+            self.repo.add_preview(&pic)?;
         }
-        preview
+
+        Ok(())
+    }
+
+    pub fn add_preview(&mut self, pic: &mut repo::Picture) -> Result<()> {
+        self.prev.set_preview(pic)?;
+        self.repo.add_preview(pic)
     }
 }
diff --git a/core/src/preview.rs b/core/src/preview.rs
index ea8e9fff..9264c127 100644
--- a/core/src/preview.rs
+++ b/core/src/preview.rs
@@ -2,6 +2,7 @@
 //
 // SPDX-License-Identifier: GPL-3.0-or-later
 
+use crate::repo;
 use crate::Error::*;
 use crate::Result;
 use image::imageops::FilterType;
@@ -26,17 +27,22 @@ impl Previewer {
 
     /// Computes a preview square for an image that has been inserted
     /// into the Repository. Preview image will be written to file system.
-    pub fn from_picture(&self, picture_id: i64, path: &path::Path) -> Result<path::PathBuf> {
+    pub fn set_preview(&self, pic: &mut repo::Picture) -> Result<()> {
+        if pic.square_preview_path.is_some() {
+            return Ok(());
+        }
+
         let square_path = {
-            let file_name = format!("{}_{}x{}.jpg", picture_id, EDGE, EDGE);
+            let file_name = format!("{}_{}x{}.jpg", pic.picture_id, EDGE, EDGE);
             self.base_path.join("square").join(file_name)
         };
 
         if square_path.exists() {
-            return Ok(square_path);
+            pic.square_preview_path = Some(square_path);
+            return Ok(());
         }
 
-        let square = self.from_path(path)?;
+        let square = self.from_path(&pic.path)?;
 
         println!("preview = {:?}", square_path);
 
@@ -44,11 +50,11 @@ impl Previewer {
             .save(&square_path)
             .map_err(|e| RepositoryError(e.to_string()))?;
 
-        Ok(square_path)
+        Ok(())
     }
 
     /// Computes a preview square for an image on the file system.
-    pub fn from_path(&self, path: &path::Path) -> Result<DynamicImage> {
+    fn from_path(&self, path: &path::Path) -> Result<DynamicImage> {
         let img = ImageReader::open(path)
             .map_err(|e| PreviewError(e.to_string()))?
             .decode()
diff --git a/src/all_photos.rs b/src/all_photos.rs
index 7c89a66b..601e063b 100644
--- a/src/all_photos.rs
+++ b/src/all_photos.rs
@@ -52,9 +52,14 @@ impl RelmGridItem for PicturePreview {
         // compute preview image if it is absent
         if self.picture.square_preview_path.is_none() {
             let mut controller = self.controller.borrow_mut();
-            let path = controller.add_preview(&mut self.picture);
-            if let Ok(p) = path {
-                self.picture.square_preview_path = Some(p);
+            match controller.add_preview(&mut self.picture) {
+                Ok(_) => {}
+                Err(e) => {
+                    println!(
+                        "Failed computing preview for {:?} with {:?}",
+                        self.picture.path, e
+                    );
+                }
             }
         }
 
@@ -84,8 +89,8 @@ impl SimpleComponent for AllPhotos {
     view! {
         gtk::Box {
             set_orientation: gtk::Orientation::Vertical,
-            set_spacing: 5,
-            set_margin_all: 5,
+            set_spacing: 0,
+            set_margin_all: 0,
 
             gtk::ScrolledWindow {
                 //set_propagate_natural_height: true,
@@ -95,7 +100,7 @@ impl SimpleComponent for AllPhotos {
                 #[local_ref]
                 pictures_box -> gtk::GridView {
                     set_orientation: gtk::Orientation::Vertical,
-                    set_max_columns: 3,
+                    //set_max_columns: 3,
                 },
             },
         }
@@ -140,7 +145,8 @@ impl SimpleComponent for AllPhotos {
 
         let all_pictures = controller
             .borrow_mut()
-            .all()
+            //.all()
+            .all_with_previews()
             .unwrap()
             .into_iter()
             .map(|picture| PicturePreview {