Understanding Associations with Multiple forms on a Page

I have a project with the following relationships:

   class Project < ActiveRecord::Base
      has_one :photo
      has_one :project_detail

   class Photo < ActiveRecord::Base
      belongs_to :project, :accessible => true, :creator => true

   class ProjectDetail < ActiveRecord::Base
      belongs_to :project, :accessible => true, :creator => true

I am trying to create a page with 4 forms, 3 to upload photos with
paperclip, and one to upload project_details.

The page is created by the ProjectsController. In that I currently
been creating the following in 'new':

    @project = Project.new
    @project.photo.save (If I save project, does it also save
    @project.photo_id = @project.photo.id (does rails do this

    @project.project_detail_id = @project.project_detail.id (does
rails do this automatically?)
    redirect_to :action => "edit", :id => @project.id, :photo_id =>
@project.photo_id, :project_detail_id => @project.project_detail_id

The above seems very redundant and unnecessary. I would like to know a
much better way of going about
this. The reason for saving and redirecting to edit was so that the
project id would be created when I upload
a photo.

The page is supposed to function by being able to upload the 3 images,
and then upload the project_details.
Since AJAX does not support file uploads, I am going to try and
implement an 'Ajaxy' solution using iframes and the
"responds_to_parent" plugin. However, first I would like to know
answers to the following:

1) What is a better approach than the one above for setting up the new
project page?
2) In my photo form I am passing @project.photo. This does get handled
by the photo controller, but the
    following does not work in the PhotosController:

    @project = Project.find(params[:project_id])

    A hidden field in the form is:

      <input id="photo_project_id" type="hidden" value="142"

The above does not work.

  So what is the correct way to achieve the above?

  This does work: @photo = Photo.new(params[:photo]) ....but is not
what I want.
  The photo model has fields for 3 photos, so I need to use the same
record for all
  3 uploads.

3) In the photos controller, what is the correct way to redirect to
the page I just came from.

    In the Projects controller I used:

    redirect_to :action => "edit", :id => @project.id, :photo_id =>
@project.photo_id, :project_detail_id => @project.project_detail_id

   ...which worked great. I thought I could just change that to
"projects/edit, but no. Something like
      :url => (page I just came from)??



Oh, and a bonus question. If I have the above mentioned relationship
with project and photo,
and I create an instance in the projects controller: @project.photo

how would I access the photo data in the returned params hash from a
e.g. to access the project data (params[:project])

would accessing photo part be (params[:project => :photo])

...and an individual element (params[:project => :photo
=> :name]) ???