Poster size prints

[maxalmon]

I need to have some poster sized prints done of my marine macros 24"x36"
Anyone have a site they could recommend and how should I save the images once I'm done editing (raw) Thanks

 

[PhilGarber]

Large Format Posters Printing seems reasonable. Never used it though.

 

[ksmattfish]

Mpix.com does up to 24"x36" C prints. Save as 8bit, sRGB jpegs if you are getting C prints made, or ask your lab.