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kazuya Nov 27, 2015 10:26 AM

a bit of math
at the moment i have my nikon D90 and im think of going full frame with a D750

i have a vr 70-300 which i know on my D90 works out at 450mm max
when i get a D750 it will obviously be 300

however allowing for the bigger sensor and 24MP instead of 12MP
would i be able to crop the photo and get a similar level of detail?
im thinking the bigger sensor will cancel out the loss of zoom from the lens,
hope that makes sense, i know what i mean its trying to explain it :)

VTphotog Nov 27, 2015 12:07 PM

Yes, I understand (I'm pretty sure) what you're asking, and as near as I can make out in my somewhat foggy head today, the answer is 'yes', the increase in pixel density with the larger sensor will give you just about the same resolution if you crop to have the same size picture you would have had with the smaller sensor.

kazuya Nov 27, 2015 12:13 PM

cheers VT
Thats what i thought too, my brain just wouldnt do the math :)

TCav Nov 27, 2015 12:30 PM

The 'Full Frame' 24MP D750 will produce 10MP 'APS-C' size images if you crop them to the same angle of view that you're getting now with your D90, which is less than you're getting now with your D90.

The D7200 will produce 24MP 'APS-C' size images, which is double what you're getting now with your D90.

kazuya Nov 28, 2015 9:19 AM

oh yea thanks TCav i never thought about it that way
not sure what to do now, i really fancied going full frame, all my lenses most of my lenses are FF thats why i was i was happy to go FF but youve made me think now which is best to go for

TCav Nov 28, 2015 10:28 AM

'Full Frame' only gives you about a stop less Depth of Field, about a stop more Dynamic Range, and about a stop less Image Noise, all while placing significantly greater demands on your lenses by capturing the extra Distortion, Vignetting, Field Curvature, and Transverse (Lateral) Chromatic Aberration that get cropped off by the smaller APS-C frame.

So while a 'Full Frame' body may offer the promise of better image quality, the lenses frequently have trouble delivering it.

FYI, the Nikkor 70-300 VR you mentioned is an example of just such a lens.

kazuya Nov 28, 2015 10:55 AM

well it is half the price and ive just noticed nikon are doing an offer with a free battery grip on the 7200
so that might actually be a better idea, my only reservation is that i had a D7000 when they first came out and it really struggled with focusing, and i did some controlled comparison shots and if anything the D90 was a tiny bit better, now i probably had a faulty model, ended up returning it, and i do know they've had their problems what with oil on sensors etc but im thinking the 7200 will be a big improvement.

kazuya Dec 3, 2015 4:02 PM

just wanted to say thanks guys, my 7200 arrived the other day, lots of nice new features plus a few ill never use, loving it so far and seems to be the right choice so cheers for pointing out the advantages over the 750 TCav
looking forward to my battery grip coming, never had a camera with one before :)

VTphotog Dec 3, 2015 5:17 PM

Hope you enjoy it. My K-3 came with a BG, which was nice, as i liked having it for my earlier istD. The extra battery power comes in handy, and the vertical grip and shutter release help with portraits. On small bodies, such as the Pentax, it also provides a more substantial grip for those of us with larger hands.

TCav Dec 3, 2015 5:32 PM

I've been using one with my D90 as well. I also have a Sony A58 and can't get one for it, so I don't like using it as much.

kazuya Dec 3, 2015 6:34 PM

it looks like you can put 6 standard AA batteries in it, which would come in really handy, nothing worse than getting your camera out and realizing it needs charging

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