How to pull and push a specific tagged docker image?

I am trying to use this Concourse CI resource to pulling specific "tagged" docker image.
I tried working out a solution using both https://github.com/concourse/registry-image-resource and https://github.com/concourse/docker-image-resource.
From the documentation, I dont see a way to achieve it.

In the below approach, Its declared as a resource and the tag remains same for rest of the execution.

  - name: server-docker-image-artifactory
    type: docker-image
    icon: docker
    source:
      username: username
      password: password
      tag: "mytag"
      repository: repo

  - name: server-docker-image-bintray
    type: docker-image
    icon: docker
    source:
      username: username
      password: password
      tag: "mytag"
      repository: repo

What I would like to achieve is, when declaring multiple steps, I would like to do something as below.

plan:
    # Pull an image with a "tag" that was derived by some step in the pipeline
    - get: server-docker-image-artifactory
       params:
           tag: my-dynamic tag

    # Copy that specific tagged image from artifactory to bintray
    - put: server-docker-image-bintray
       inputs: ["server-docker-image-artifactory", "my-dynamic tag"]
       params:
           load: server-docker-image-artifactory
           tag_file: my-dynamic tag

Right now... i am unable to provide something like above. It always ends up pulling the latest image.
I tried the params such as "load", "load_file", "load_tag". But no luck
Any directions?

Start by reading the documentation and parameter handling in the docker-image-resource and registry-image-resource repositories, especially the existing load, load_file, and load_tag options. Done means a pipeline can pull a dynamically selected tag and copy that exact tagged image between registries rather than defaulting to the latest image.