Light - sharpness vs contrast

I'm trying to step things up this summer and get some better shots outdoors. I'm pretty comfortable with my camera settings and the science of photography. I'm not so comfortable with the part concerning actually taking interesting pictures, lol.

So... right now I'm thinking about sharpness in nature and wildlife shots. Assuming shutter speed is sufficiently high for hand holding the lens and the aperture is at a sweet spot, does better light give us more sharpness? Or does bright light just change the contrast/texture which makes for a shot that just seems more tack sharp?

My gloomy day photos look like gloomy day photos. I can liven them up and sharpen in LR, but they are still not impressive. Distance permitting, I can take the same shot at the same aperture with straight on flash and it looks great, assuming this is a flower or an animal. Grandma's whiskers, not so great if they are glistening in the light.
Am I on the right track here with light? I want strong, almost harsh light for a good nature shot? If this gloomy wet winter ever ends here in NY, I could go out and experiment.

Thanks for any tips.

Post a few of your sharp and not so sharp images with exif data...People can give better advice then...

I tend to increase the contrast and darken my shots just a little in post processing and it gives the illusion of sharper photos. Gives them pop.

You need to be more specific when you talk about "better light". Light is infinitely variable. Do you mean sunlight vs shade? Or direct versus diffused, as on an overcast day? When it comes to nature photography, I actually prefer overcast days because you do not have sharp shadows. If shooting black and white on an overcast day, with film at least, you can up the contrast some through manipulation of exposure and development and the use of filters. For color, well you are kind of stuck with what you have.

There is sharpness and then there is apparent sharpness. Contrast plays a part in apparent sharpness. This is where image accutance plays a part. A contrastier image will appear to be more sharp than one which is dull or muddy, even though the actual sharpness levels could be the same.

Thanks. I think the problem is that I need to learn more about light and post processing. I'm talking a heavily overcast day. I can't get a color picture that I'm happy with. For an animal or flower, I get what I consider a sharper picture when it is strongly lit from the front. But I think maybe its not really sharper, it just looks that way from shadows accentuating the texture. I read up on acutance, interesting.

Here are two similar shots, both on a dark day. The one on the right is tweaked in LR, but still seems blah. First time posting a pic here, so hope I got the sizes right.




edit: I didn't do the exif on export right. d7k, iso500,300mm,5.6, 1/600