Need help with a color change

[Sara Martin Griffith]

I am working on an American flag and I would like some feedback. The pattern is done with linked double crochet and the line between the blue field and short stripes is jagged when I change colors. Is there something I can do to make it straight? Photo attacked. I have searched google, you tube, pinterest, ravelry just to name a few.

[Granny Square]

I haven't actually DONE linked double crochet,  but I have an idea that the whole 'grabbing a loop of the prior stitch to close the gap between the stitches' transaction is causing the problem.  The only thing that comes to mind, that is fairly painless, is to make the blue piece separate from the upper stripes, and mattress stitch (with tapestry needle and yarn, there are lots of tutorials out there) the vertical seam between them at the end.  Mattress stitch is invisible, some tutorials demonstrate the technique by using a completely different color to sew 2 pieces together and you can't see the 'wrong' color at all when it's done.

In other words, rip both sides down just a few rows to the white stripe in the photo, and just work across the red and white stripes, and then make the blue part by starting the first row in the white stripe below like you have done, except don't connect it to the side stripes after that; so it will be sort of a 'flap'.  Then mattress stitch the vertical seam.

[Sara Martin Griffith]

I thought about doing that way, but just wanted to check and see if anyone had any other ideas. Thanks for responding and thanks for letting me know how to check and see if my questions posted. I got sidetracked in the middle of the first post and could not remember if I had submitted it. Thanks again

[bgs]

If you look close at pretty much any crochet project using color changes in order to make an image you will pretty much always find the colors overlapping so you do not get a good crisp line.  Its just the nature of crochet stitches.  I bet if you could find a close up photo of pattern you are working on it would look just like yours.  A few years back I wanted to do a square with a Christmas tree in it and hated the look of the edges of the trees

http://www.crochetnmore.com/rowcountchristmastreeafghansquare.htm

https://www.e-patternscentral.com/detail.html?prod_id=13040&cat_id=583&criteria=

I did some research and found this 

https://books.google.com/books/about/Reversible_Color_Crochet.html?id=giNjDwAAQBAJ&printsec=frontcover&source=kp_read_button&hl=en&newbks=1&newbks_redir=0&gboemv=1#v=onepage&q&f=false

She flips the 2 colors back and forth while making a stitch where the color changes.  The link above shows several pages with some of the changes.  I did buy the book but life got busy and I never revisited the technique and never made the square.