Very nice shot. I would suggest using smaller than F4 aperture the get the most of the flower in focus. Since you shot it at the longest end of your zoom, I suppose you couldn't get closer to the flower. I would suggest to do a digital zooming by cropping the image closer to the flower.
Thanks for posting.
K20D, *istD, Z1-p, SF-1n, K1000
DA*16-50/2.8, DA*50-135/2.8, DA*200/2.8, DA 70/2.4 Ltd, Pentax M 28/2.8, Pentax K 55/1.8, Pentax M 200/4, Takumar 135/2.5, Kiron 105/2.8 Macro 1:1
|Douaumont Ossuary by Eric 54-BNF|
from Armistice Day
|Silhouette at sunset by Jill Hancock|
from Portrait Lens (around 80mm or equivalent - please check the full rules)