Time Stack - How Its done

First you need to have taken a few pictures with the same position but with slight changes to the background, e.g. clouds or colours in the sky or movement. Then set the first or the last picture as the background (first image you open in Photoshop) depending on if it is the first or last it will create a different movement of motion.

Then there are many ways to get the layers on top of your background picture.

I just dragged the file from its folder 10 at a time. I did this going in order of when the picture was taken.

Next you need to select all the layers , but not the background. Then change the drop down from normal to lightened. In some cases changing it to saturated in some frames can bring out more colour.

This is where you can change the shadows. Ideally you want the shadow at 0 and the rest of the options you can edit to see how you like it. The one shown above is how I have set it for most of my pictures.

When you are happy with the balance of lightened for each picture save it, Then you will want to merge all the layers together by right clicking when the layers are hi highlighted.
Then you will want to still have the merged layers elected and go to shadows and hi lights. This will open a menu. Then you are done, you can also edit the levels of the picture to but you still have to merge the layers to effect all of them with your adjustments.

This is the out come of some of the pictures from my 4th shoot, as you can see, I have taken pictures of the sky and managed to get the verity of colour. Also have managed to caption the motion of the clouds.