How to copy a lasso selection for rotoscope work...

[vinoscopy]

Dear people smarter than me,

I need to do some rotoscope work on a piece of video in Photoshop. I can't use After Effects in this instance, I have to use Photoshop. So I want to cut out the image of a submarine as it is sinking slowly. The sub is slightly rotating as it sinks, so it's basic shape changes only slightly from frame to frame. What would make my life much easier in working with all 200 frames, would be if I could use the lasso tool to draw around the sub and cut out the shape, the copy that shape of lasso selection, and apply it to the next frame around the sub, and then just alter the shape of the lasso, to the now slightly changed shape of the sub. This would speed up the process infinitely, so I don't have to redraw the shape on every single frame. Is there a way to do this? Help, advice, tutelage in this area would be so very much appreciated. Thanks in advance, and I am glad there is a place I can go where people smarter than me are willing to help. Thank you so much!

Cheers,
Carlo

 

[IamSam]

Hello and welcome to PSG.

I would personally use the Pen Tool for this. Once you make a selection with the Pen Tool, you save the path. Duplicate the path for the next frame and make whatever subtle changes need to be made using the Pen Tool. This would go very fast and be much more precise.

 

[IamSam]

You can also alter the duplicated path using the free transform function (Cmd/Cntrl + T), which also makes things easier.

Here I have made the subtle change in the path from one frame to the next.
I lowered the opacity of the sub so you can see the path.

First frame...


The blue guide line shows the subtle change in the second frame....

 

[IamSam]

But if your just wanting to copy a lasso selection to a new layer, Highlight the layer to be copied, make your selection with the Lasso Tool and hit Cmd/Cntrl + J to copy.

edit: A Lasso selection is a loose selection and not as precise as the Magnetic Lasso tool, Quick Selection tool, or the Magic Wand tool.

 

[IamSam]

You can save a selection, but you would be very limited as to how you might alter that selection using free transform. This is why I proposed the Pent Tool as the best option.





I think I'm talking to myself here.

 

[vinoscopy]

Ok, wait a minute here!!! First off, let me apologize to you IamSam. I have never posted to a forum like this before, so I did not think in any way shape or form that I was going to get a response so quickly. I just posted my question and then went to work, thinking I would check it tonight when I got home. I certainly did not expect such a fast reply, and also such a very thorough reply offering optional solutions to my problem. So for that I apologize for not checking back to soon, and also want to THANK YOU sooooooo much for such great help. Holy crap!!! You even showed me an example using a sub picture which is exactly what I am trying to do!!! That was awesome!!!! Thank you, thank you, thank you!

I will try the pen tool for sure, but that is a tool that I have never used before, so this is a good project to force myself to learn it on. This is great, I will tackle this now using your advice. I may have one or two questions more as I dive in, but hopefully it will be as easy as you described. I knew there must be a way that Photoshop could do this, and I am so grateful to for showing me the path forward.

Sincerely, thank you,
Carlo