ISO vs reach (or FX vs DX)

Hi everybody.
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.
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.
So lets consider the following:
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).
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.
Question is: will the D750 give me 'better IQ' (eg, detail, noise) than the D7100?

Oli

Check this article - you may need to read it twice!

DX or FX for Sports and Wildlife Photography

Here is a test comparing the bodies. N750 is too new, so D610 is substituted (all these are 24 megapixels, and current models).
Nikon D750 versus Nikon D610 versus Nikon D7100 - Side by side camera comparison - DxOMark

You will need to use lenses 1.5x longer on FX, to see the same view DX shows. If using the SAME lens, FX will show the view half again wider (uncropped), which then when enlarged less to show larger frame as the same size as smaller DX frame, will show size of contained subject objects reduced proportionately. With same lens, cropping FX to 2/3 size will show the same view as DX. OR enlarging DX half again more to view as same FX size, will show the same subject sizes.
You will need to use lenses 1.5x longer on FX, to see the same view DX shows. The cost of the long FX lenses will be VERY noticeable.

I would forget the diffraction limiting idea. You will NEVER be able to do a test showing that it exists. Diffraction certainly does exist, and it gradually increases as we stop down in any lens, but the notion of pixel size limiting it is silly.

OliMarshall said:

Question is: will the D750 give me 'better IQ' (eg, detail, noise) than the D7100?

Oli

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Absolutely the wrong question to ask, but the answer is, "Yes, but at what cost?"

The question you need to ask is, "How much better is a D7100 than my D90 in terms of noise and IQ?", the answer to which is, "So much better it might just make your head explode."

The D90 at 1600 is noisier than the D7100 at 6400 - I know, I have both. The D90 is 12MP's, the D7100 is twice that, with less noise. Better IQ, better sharpness (no OLPF), more pixels per bird, it's the camera you both want and need.

Just so it is said, if you shoot with a D750 and crop you're actually getting a smaller image than you would from your D90. Doesn't make sense. And so it's also said, I tried this moving from a D7000 to a D800. 14 months later I bought the D7100 I should have bought in the first place.

Save your money. Get a D7100 and a 150-600mm (Tamron or Sigma) for the same price as the D750. Those birds will thank you for it.

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Why are all oilmarshalls posts empty all i can see is .....

mikew said:

Why are all oilmarshalls posts empty all i can see is .....

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They all say Edited 11:01 or 11:02, so I assume the ... was edited in?

He just zapped his posts I think.

Here's one I got via notifications:

Thanks.
Yeah I've read that and many other articles/threads/reviews - you name it, I've probably read it. It's easy for people like Nasim, who are pro's, to say FX is better (even when backed up by solid arguments). For the rest of us it comes down to 'are FX advantages financially jusifiable?' or 'is a 1 stop advantage worth £1000' (D7100 vs D750 current UK prices). Maybe those questions are too simple.
But I thought I'd ask for advice on a very specific set of shooting parameters which someone perhaps has first hand experience of (or at least something similar).
I guess I just don't want to end up going FX and thinking 'meh' when I look at the shots.
If I could rent both camera's I would, but that's not possible.

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Gorf said:

He just zapped his posts I think.

Here's one I got via notifications:

Click to expand...

If he did well is he worth the membership ? not really the way to behave

I suppose it was my fault for questioning his question. Here's the PM he sent me...

It is NOT the wrong question to ask! How arrogant and patronising of you!!
F*CKING DUMB C*NT YOU ARE.

I suspect we're better off. But what do I know?

BackdoorHippie said:

I suppose it was my fault for questioning his question. Here's the PM he sent me...

It is NOT the wrong question to ask! How arrogant and patronising of you!!
F*CKING DUMB C*NT YOU ARE.

I suspect we're better off. But what do I know?

Click to expand...

....

And my apology for the (edited) language.

oooh can I put a best answer on the ... 's

I'm sorry but you dont flame the "residents" when you arrive at a new forum

Shame really as it looked like it could have been a useful thread for people contemplating the same.

BackdoorHippie said:

I suppose it was my fault for questioning his question. Here's the PM he sent me...

It is NOT the wrong question to ask! How arrogant and patronising of you!!
F*CKING DUMB C*NT YOU ARE.

I suspect we're better off. But what do I know?

Click to expand...

Jake,

I know it's not really funny but that did make me laugh. I wouldn't clear a special place for the Christmas cards.


Sent from my iPad using Tapatalk HD

BackdoorHippie said:

I suppose it was my fault for questioning his question. Here's the PM he sent me...

It is NOT the wrong question to ask! How arrogant and patronising of you!!
F*CKING DUMB C*NT YOU ARE.

I suspect we're better off. But what do I know?

Click to expand...

Lol! We'll have to give you a badge!

I was amazed when I opened it up. I thought, "This has to be some kind of joke!!", but then came here and saw differently.

I sent him a peace pipe in reply, but as I said, I suspect we're better off with him moving on.

traceyjj said:

oooh can I put a best answer on the ... 's

I'm sorry but you dont flame the "residents" when you arrive at a new forum

Shame really as it looked like it could have been a useful thread for people contemplating the same.

Click to expand...

And that's sort of what I told him in my reply. If it's arrogant and patronizing to warn someone not to make the same mistake you made then I guess the shoe fits.

Gorf said:

Check this article - you may need to read it twice!

DX or FX for Sports and Wildlife Photography

Click to expand...

Gorf, Thanks for sharing. This was a very article which has increased my desire for a full frame camera. My current struggle is whether to by a D3s, D750, or D4s. I'm really struggling between the D750 and D3s.

WayneF said:

I would forget the diffraction limiting idea. You will NEVER be able to do a test showing that it exists. Diffraction certainly does exist, and it gradually increases as we stop down in any lens, but the notion of pixel size limiting it is silly.

Click to expand...

I doubt diffraction had all to do with it but yesterday when testing out how far I could go in upping ISO while stopping down I noticed that 1600 combined with f/36 or lower seriously started fuzzing my 100% image. If I have better light today I'll check if I see the same happen in the lower ISO modes. That's evidently with my cam.