Forum: Photoshop

Subject: making super fine selections

ebsmooth opened this issue on Jan 31, 2005 ยท 12 posts

ebsmooth posted Mon, 31 January 2005 at 11:55 AM

hello all, have a question with regard to making selections that are very fine. what i'm trying to do is take the sky out of some of my pictures to replace with a CG sky. that's not a problem with some of my architectural photos but some have trees, power lines and other really small objects in them. i've tried the magic wand and magnetic lasso but both of them miss a lot of the smaller details. what would be the best way of going about this? thank you in advance for your time and any assistance!!! attached is an example. i was going to each individual section in the power line tower and was taking forever and a day to get. you can see what i'm talking about, the dull blue sections are where the old sky was. regards, eb

ebsmooth posted Mon, 31 January 2005 at 7:26 PM

thank for the assistance. the link will surely come in handy as i have no idea about quick masks...lol, i'm still learning photoshop!

Hoofdcommissaris posted Tue, 01 February 2005 at 2:54 AM

Another way of doing it is to start using alphachannels (or an alpha mask) with color selections. I upped the contrast (with an adjustment layer so no pixels are harmed)

Hoofdcommissaris posted Tue, 01 February 2005 at 2:55 AM

Then make a selection with 'color range'

Hoofdcommissaris posted Tue, 01 February 2005 at 2:56 AM

And make an alpha mask.

Hoofdcommissaris posted Tue, 01 February 2005 at 2:56 AM

That can be cleaned and large sections filled with white

Hoofdcommissaris posted Tue, 01 February 2005 at 2:57 AM

A second selection on the thin lines that are lower, selecting that and painting in the resulting selection in the first alpha channel

Hoofdcommissaris posted Tue, 01 February 2005 at 2:58 AM

And finally making the alpha a mask

Hoofdcommissaris posted Tue, 01 February 2005 at 2:59 AM

In this case I darkened the power lines to better match. And you can continue painting stuff back in the layer mask. But the original has to be a lot larger than this for good results...

ebsmooth posted Tue, 01 February 2005 at 9:38 AM

wow, thank you for doing that, your's definitely looks much better then what i did! i can see i still have tons to learn. the original is 3008x2000 but i shrunk it down just to post here as it would have been huge! i know what i'll be doing today...heh heh!!! thank you again for your generous help, i greatly appreciate it!!! eb

retrocity posted Tue, 01 February 2005 at 10:45 PM

hoof, you are a great help here in the forums and an invaluable resource. thanks for helping :) scott

ChuckEvans posted Wed, 02 February 2005 at 12:34 PM

Hehe, Scott, I was thinking about he long reply he gave me about panels and now this. Some might say, "beyond the call of duty". Now, just where IS that box of "attaboys"?