Q: set iphoto library permissions for multiple users

There is no good way to deal with it, outside of using an external, set to ignore ownership and permissions.

You could try putting the Library on a disk image, set to ignore ownership and permissions, but there is no guarantee that this will work.

An iPhoto Library is a database built on a complex ecosystem of interlocking files, databases and metadata. The Finder's permissions are of no relevance at all here. Simply, iPhoto is designed for a single user. It's not a server, and the only way to get it to share is to move it to another disk.

It's not iPhoto that's ignoring the permissions. It's a setting for the disk, and you can't have that setting on a start up disk. If you try your Mac won't start.

What part of this

An iPhoto Library is a database built on a complex ecosystem of interlocking files, databases and metadata. The Finder's permissions are of no relevance at all here.

is unclear?

BUt if i give read & write permissions to other users in the get info pane shouldnt it work? Or could it be that since i didnt apply the permissions to enclosed items it didnt work?

iPhoto is writing to the iPhoto library and changing files inside the package and adding files with a different ownership even if the other users are only trying  to read the library. That is why you can no longer have an iPhoto library on a CD or DVD- You ned read/write access for all files and folders inside   the package. As soon as another user opens an iPhoto library, the owership of some items in the library will change to the other user.

The only supported way to share an iPhoto library has been described by Apple here - see this link:  iPhoto: Sharing libraries among multiple users

We understood perfectly, that you want to share your library on an internal drive, and that is why I sent you the link to a document by Apple Support, that states, under which conditions a photo library can be shared -  only on a separate disk or partition, correctly formatted,  with the ignore ownership flag set.

I removed the optical drive from my MacBook Pro and replaced it with a second internal 1 TB drive. That made it possible to share the library on an internal drive. Your solution with the SD slot will probably work as well.

Andy you can not do that

Thus

iPhoto: Sharing libraries among multiple users - Apple Support

What you want is not possible - yelling and having a tantrum will  not change that - you can not do that at this time

LN

What part of it is impossible do you fail to comprehend?

LN

PS - no Apple fanatics here - simply users with no power rot change anything or explain why anything but due to their experience do have  the ability to help people use iphoto as it is - some users apparently are incapable of understanding that simple fact and think that posting in Caps and saying over and over that they do not want what is available but want something that does not exist will make things different - it will not - it is what it is and no one here can change that - and no matter what names you call, how much you attack volunteers tying to assist yo  or how much you yell or how big a tantrum you throw nothing will change

Why do you think the limitation - single user database - is a design flaw?  You can call it that, but I call it a design decision.

It is Apple's decision, to make it possible to have a small, free photo application that comes with every Mac. Even Aperture, Apple's professional photo editing and image database software, does not support to share the library. Apple supports several ways to share selected photos quickly and easily, but keeps the library private.

Professional databases that support shared databases for professional purposes are much more expensive.

The use of the overly large font

I DO NOT want to move it to an external drive as I want to carry it on my mac wherever I go.

is what looks like a tantrum. It feels rude to the reader.

Then there's that calling people whose help you are seeking 'fanstics'. That certainly feels rude.  You may consider iPhoto's inability to do what you want to be a design flaw. Bully for you. It doesn't matter. No one here designed it. No one here can change it. But you know this, you're on the forum long enough, you're profile says you're a Mac developer, but you seem unable to grasp the basics of the forum, nor, indeed, sandboxing. Your question was answered in the first reply, I have no idea why you keep asking it.