Selection woes: lost track whether I'm adding or subtracting - intricate selection

[VectorCat]

So, I get "Add" versus "Subtract" to a selection, but I have some how backed myself into a corner in which I can't tell what the selection "thinks" it's meant to do.

I'm selecting a machine from its background. The machine has lots of hoses and so, lots of areas where you want there to be a hole in the selection. In an effort to get the best selection, I've zoomed in, and some how when I think I'm adding, the selection ends up getting smaller! It is not a matter of knowing what I want or seeing what I want. It's a matter of the lasso tool not producing what I need it to.

I may have to scrub it and start over, but before I do, is there a method to help me gain control over the selection so that when I want to add to my selection, the selection actually does add?

Hope I've explained myself clearly. Thank you for any tips!

[VectorCat]

Note: if I were to attack this fresh, I'd first get the outer selection done first, then go in and subtract from in in the area of hoses, or holes in wheels which need to be seen through.

[Ron P.]

I would agree with knocking out the background first, unless it's also real complex.

Do you use a mouse or pen tablet? I've used a pen tablet for so long, I find it difficult making decent selections using my mouse. I don't use the lasso, just the Selection Brush.  My pen is setup where pressing the bottom button on the side along with press-drag of the pen changes the size. I'm constantly changing the size, and sometimes the hardness.

Now that leaves your main problem, changing from Add/Subtract. Using the selection brush, once the initial selection is made, it changes to Add. I rest my thumb on the Alt (Option) key on my keyboard. When I have to subtract, pressing the Option (in your case), temporarily changes the selection brush to Subtract. Brush where I need to subtract the selection, release the Option key and I'm back to Add. Just make sure you have Show Pixel Selection set in the View menu. Just watch the marching ants. If you brush on the inner side of the marching ants, you're adding, if you brush on the outside you're subtracting. That's what I use anyway. When I zoom in, I'm changing the size of my brush to match the zoom level. Otherwise, the brush will appear larger and harder to manage the selection.