Thank you MT. D7000 does provide more pixels than equivalent cropped D750. So in some instances it still makes sense to use D7000 for long zoom, as you described.

You are right!!! Crop sensor is 24x16mm, FF is 36x24mm. So it is 1.5X for each dimension. Total FF area is 2.25 that of Crop. So Crop Megapixel density is much higher than FF.

From discussions in this thread it appears crop sensor is preferred over full frame for wild life.

There are a few suggestions to do that. I will try that out over the weekend.

I have a Nikon D750 and D7000, and a sigma 150-600 lens that I use for wild life photography.

For a long time my understanding was that for the same lens, a cropped sensor camera has a longer reach compared to full frame. There is an "equivalent focal length", in this case 225-900mm. Taking wild life pictures with the DX camera is preferred because of this.

But then I read that lens focal lengths don't change. The term equivalent focal length is misleading. It really is angle of view. Because full frame camera has a bigger sensor (in this case 1.5X). It captures more picture compared to cropped frame, and gives the illusion of less reach.

Also the D750 is 24 megapixels, compared to 16 on the D7000. Even considering the sensor size differences, the "Megapixel Density" are identical. This means that if I start cropping the pictures from both cameras, I should get the exact same resolution - even though I am cropping more on the D750.

Therefore I should not be using the D7000 at all - wild life or otherwise. For lens reach/picture resolution there is no difference, and D750 offers so much more.

Is this a valid? I like to get opinions from fellow UHHs.

Thanks for checking out Meives. That was my issue. I had the camera a long time so I have no concern. I only recently purchased the lens and found it hard to maneuvre - size, weight and focus. The Keeper rate had gone down.

I was hoping the issue is my skills with long lens, rather than the lens itself. So far all suggestions seem to confirm that.

Wakodahatchee wetland in Delray Beach. It's a great place to photograph birds, specially early morning and late afternoon. It's about 40 minutes from Davie.

It was shot with tripod. Maybe it was the sunlight on white feathers - I hope its not the lens. I will need to increase the speed for future shots. Thanks.

Thanks yes should have done that. I normally don't shoot in continuous mode.

Thats a good suggestion. f7.1 should be a good enough DOF for this.

Thanks all. I had my camera preset to ISO 1000, f8, and aperture priority. When I saw this in the backyard I just grab the camera and shoot. I am now setting the ISO to 2000. Hopefully no motion blur next time when fast action occurs.

Thank you all. Makes sense. I was hoping this is the answer, as opposed to depth of field of my lens at 600mm.

This is taken with Nikon D7000 and Sigma 150-600mm C on a tripod. As indicated in EXIF, f 8.0 and 1/800 sec. Any idea why it is sharp around the eye and blurry at the beak? Thanks.

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Have them ship to a UPS store close by and you can pick it up. Typically a $5 UPS charge.

150-600

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