crop/zoom

Hi
How far should i expect to be able to crop, zoom in a picture before it becomes unsharp? Below are 2 pictures. the first is reasonably sharp The second is the same photo zoomed in 50% and you can see that some sharpness has been lost. Is 50% too much zoom? How much zoom can I expect to get?
D7000 70-300mm vr nikor lens @ 300mm 1/800 5.6 800 iso. Focus set to single point,vr on, resting on my window seal

It really depends what you want to do with the image. The more you crop, the less you can enlarge. The full image from a D7000 can probably make a decent 16x24 if it is sharp to begin with. 50% crop, maybe a decent 11x14 or 8x12, but it depends on your expectations.

The problem you have with the above image is it is not sharp to start off with, so cropping makes it look worse. A 50% crop of a sharp image should still look pretty sharp.

Even in the first picture it does not look like it is quite in focus. what is the exif data on the shot?

That's a tough one. I always have difficulty with shots like these, especially when using autofocus. When I look at the cropped version, it seems that the focus is really on the branch the bird is standing on. I would have used manual focus and f/8 for a little more depth of field.

I like the photo anyway, especially the cropped one.

You really have to experiment and see what works for you and your equipment.

I agree with barbara, looks like the branch is the sharpest element. One thing I've noticed in shooting small subjects is that the focus box is not always where we think it is. Many times when I show the focus point in the nikon software, the red focus box is off to the edge of the subject.

If it was at 300, your gonna need a fairly fast shutter. The more you zoom in sometimes it gets blurry from a bit of shake.

The 70-300 VR is a fine lens but it does get soft past 200mm wide open. I used it at a baseball game last month and wasn't real happy with any of the shots at 300mm at 5.6. It's a great 70-200.

Try not to shoot past 270mm with that lens. Move a little more closer if possible. Are you using AF-C, 9 or 21 AF points?

Thank you everyone for the responses. I went back out this am to try again. I backed the zoom to 270mm and stopped at f8, use single point focus, shutter speed 1/1000th,iso 800, VR is on. This picture was taken from my vehicle. I folded a towel and placed it on the window and rested the lens on for stability. I turned the vehicle off to insure i was not getting vibration from it.

I should probably also add that I set the shutter on quiet mode because I read that this lessens the mirror slap and can increase sharpness


I took over 100 pictures and did manage to get a few of a red winged blackbird that turned out good. I added some fill light to it so you can see his head better