LR 4 on one machine; LR6 on a new one

[JeanMichel]

Hi,
I am replacing a MacPro (2007 vintage) with a new iMac. My images live on 3 internal hard drives within the MacPro (all backed up on external drives) with the catalog on a fourth one. I thought of simply moving the 3 internal drives into an enclosure and attaching that to the new iMac, however it might be very useful to keep the MacPro as is and networking it the iMac so that my spouse could use LR4 to keyword and rate images. Developing, etc would be now done in LR6 on the new machine -- note that the MacPro is too old to run anything newer than LR4. New images will probably no longer be added to the existing drives but rather imported into the new 3TB iMac drive (with backup to an Airport Time Capsule). Is keeping a LR4 catalog on the MacPro and a LR6 catalog on the iMac a workable solution in order to have someone rate and keyword images in LR4; if anew keyword is added in LR4, will that keyword automatically appear in LR6, same for star or colour labelling?
Thank you,
Jean-Michel

[BobShaw]

Unfortunately you need Mac Pro Early 2008 to run the latest OS. Your thought of having two catalogues sounds to me a bit like having two two backsides. One of the reasons I don't use Lightroom is that it can't run on a server.
I expect there would be no way to have keywords on one appear on the other.
I suggest just to have one catalogue on the same drive as the data attached external to the iMac.

You could possibly convert the Mac Pro to a server and use it for the backup, but it's a huge piece of real estate.

[Hoggy]

I've had some experience with this between LR3 and LR4.  One [Windows] machine wouldn't run anything newer than LR3 - and I wanted to be able to work on images from the LR3 machine.  Just metadata like keywording and such - no develop settings for obvious reasons.

It's been a while, but I think as long as no develop settings have been done to either catalog - I was able to do the non-develop metadata (keywording, etc) from the LR3 machine before doing anything on the LR4 machine.  I just had to make sure I saved the
Metadata to Files from the LR3 machine before doing anything on the LR 4 machine.  Then from the LR4 machine, I did a 'Read Metadata from Files'.  All the image files were stored on a 'server' machine, so both accessed the same DNG's.  I think it would still work in that fashion even if using camera-original-RAW's..