New Post: PNG compression

hi, i have a jpg file, 1024x613, 170KB.

I resize it into 596x549 png format, but the resulted file size is kinda big, 487KB.
I tried online compression tool tinypng, and it's able to reduce the size to 180KB.
How do i achive similar file size with magick.net ? or at least around 200KB

thanks
juna