i can see a particular folder in photo stream on my iPad and iPhone but cannot see this folder on my iMac, even though it says there are 102 photos?

I can see a particular folder in photo stream on my iPad and iPhone but cannot see this folder on my iMac, even though it says there are 102 photos?

What do you mean? Photo Stream does not hold folders, only Photos and videos.

Are you asking about "My Photo Stream" or "Shared Photo Stream"?

The Photo Stream does not necessarily show the same photos on all devices, see:

See this document: http://support.apple.com/kb/TS3989

i.e. the paragraph: rapI see different photos in My Photo Stream on each of my devices.

Your device will keep up to 1000 photos, even if they are older than 30 days. Photos older than 30 days are removed from the iCloud server, so all devices may not have the same photos, depending on when you enabled My Photo Stream.

If you prefer to have only the most current photos in My Photo Stream on each of your devices, and delete the older photos:

• If there are any photos in My Photo Stream that you want to keep, save them to your Camera Roll, then back up your Camera Roll and other data using iCloud or iTunes.
• Turn My Photo Stream off in Settings > iCloud > Photos (on a device using iOS 6, go to Settings > iCloud > Photo Stream). Confirm that you wish to Delete Photos.
• Turn My Photo Stream back on. iCloud will automatically push your stored photos to your device.
• Repeat these steps for each device.

what version of iPhtoo and of the OS? My PhotoStream or shared PS? have these photos been added by you or by other subscribers to a shared PS?

LN