Thumbnails do not show changes

[gemjane]

I have used IV for several years and I love it. Recently I had to replace my computer, and then my camera (!). I am trying to learn how to use my camera and use irfanview (which I think must be a different version) with the images from the "new" camera--I finally hit on a way to make IV the default editor--don't know how I did it. But the thumbnails, after I edit the images, do not show the changes. When I open the thumbnail images the pictures are as I edited them, but I need to find out how to look at the image and see it correctly without having to open it every time.

Any help appreciated!

Jane

[Skippybox]

Are you referring to the thumbnails in the IrfanView Thumbnail Window or in Windows Explorer?

[gemjane]

Skippybox--I mean when I open a folder of IV thumbnails. I don't think I am using Windows Explorer. I didn't think I was viewing things in the Windows Viewer.

OK, I see that if I put them in a folder on my desktop, I guess they are in Windows. Hope that gives you enough info.

Thanks.

Jane

[matera]

See my reply in other thread re: camera software

[Skippybox]

OK, I see that if I put them in a folder on my desktop, I guess they are in Windows. Hope that gives you enough info.

Well, this can be a complicated issue. First off, Windows caches thumbnails in a database located in the folder to speed up display, which means that the copy of the thumbnail when it was initially cached is shown instead of the real thumbnail. So, whenever a file gets edited or even replaced by a totally different file with the same name, the old thumbnail is still shown.

To solve this, you can either refresh the thumbnail, delete the database and have it rebuild, or stop caching thumbnails in Windows altogether. Or you can make a new folder if you wanted, but that isn't really necessary.

Method 1. To refresh a single thumbnail, right click the thumbnail and choose Refresh Thumbnail in the context menu.

Method 2. To delete the database, show hidden files and folders (Folder Options, View, Advanced Settings), and delete the Thumbs.db file in the folder.

Method 3. To disable caching to have thumbs generate fresh (slow!), go to Folder Options, View, Advanced Settings, check Do not cache thumbnails.

Method 4. Copy the files to a new folder to force a new database to be created.

While these methods should resolve your issue, you could still experience some problems. Even if the thumbnail is freshly generated, the way Windows creates thumbnails and updates them can still cause mismatches. One of the reasons is EXIF metadata in JPGs, which contains an embedded thumbnail.

Windows tries to use that embedded thumbnail if available, instead of the actual image. If you save a picture with the original EXIF, then the embedded thumbnail will be old. Windows has a strange routine that checks for mismatch, but if the changes were slight enough, then they will be missed. There are programs that can rebuild your EXIF thumbnail, or you can just skip saving the EXIF if you don't actually need it.

Another problem is lossless rotations, which can be performed in IrfanView. While the embedded thumbnail is rotated during such an operation, for some reason it isn't always noticed by Windows.

See the related threads Thumbnails in Explorer not recalculated and Thumbs randomly don't rotate for information.