<p>Hi everybody.<br /> So I've been using my D90 for nearly 5 years with few complaints. I have 4 Nikon lenses - 18-105 DX, 35 f/1.8 DX, 70-300mm VR, 105mm Micro. I know the 70-300 isn't the greatest birding lens, but it's all I have and all I'm likely to have for the forseeable future. That's why I'm basing my post around that lens only.<br /> This year I got a bird feeding station, but I'm finding that in order to keep a high shutter speed (say 1/1000) with the 70-300 at, say f/8, my ISO is creeping up to 1600 and things are getting noisy and I'm seriously considering moving to FX. My concern is that I lose reach.<br /> So lets consider the following:<br /> At 300mm, 1/1000s, f/8 and ISO 1600, I take a (properly exposed and focussed) photo of a bird that is, say 15 feet away using firstly a D7100, then a D750 (or a D610 assuming the sensor is the same as the D750). I know about 'crop factor', but that's not relevant as I only have the 70-300, so I accept that I will 'lose reach' on the FX camera. Also, the D7100 lacks the OLPF or AA filter, which <em>may</em> result in more detail.<br /> The bird doesn't fill the frame in either case, so cropping in post is required (obviously I need to crop more with FX). I crop each image so that the bird fills the frame vertically.<br>
My question is: will the D750 give me 'better IQ' (eg, detail, noise) than the D7100?<br>
Thanks.<br /><br>
Martin<br /></p>