Category Subcategory and keyword tags

[mcElduff]

I am new to PSE.
I need to tag more than 20,000 digital images of events captured over a 10+ year period.
I have already filled the Task Pane window with Categories, Subcategories and Keyword Tags and need to use the scroll bar to view all of them - even with all categories collapsed!
This means that when I assign tags to photos I have to scroll up or down as necessary in order to select the appropriate tag - a very cumbersome task. Also certain categories are no longer relevant to the current tagging exercise and I am unlikely to ever need these again.
However, if I delete these categories then the associated tag is lost in the photos.
My question is this. Is there any way I can hide Categories and associated tags that I no longer need showing only those categories relevant to the current session. I dont want to start a new catalogue as the solution to this problem.

[dj_paige]

I'm at work now, I don't have PSE with me, but I thought you could drag the categories up or down to change their position in the list. You could put the categories you no longer use at the bottom. (There may be a tag option you need to check to enable this, I'll check when I get home.)

Another thought is to combine categories so that there are fewer of them. For example, if you have categories of football, baseball, basketball, you could combine them into Sports.

And don't feel bad, I have a very long list of categories and tags as well.

[johnrellis]

To add a little more detail to Paige's reply, you can reorganize your keyword subcategories and tags by dragging them to new positions or new subcategories. You can also right-click the tag or subcategory and select Edit to change its category.

Another tip that helps with large numbers of tags: Turn off the thumbnail icons that appear to the left of the tags, which will let you see more tags in the pane and do less scrolling. Go to Edit > Preferences > Keyword Tags And Albums, and click the left radio button under Keyword Tag Display.