in for a surprise. A D90 image taken with a quality lens by someone who knows what they're doing will not be significantly different from a D610 image taken with a quality lens. Most people see a big difference because they go from a DX with a kit lens to FF with better lenses. I've you are printing large, cropping deep, or have shots where the broader DR is an attritube, then sure you'll see bigger differences.
I made the switch almost 2 years ago (has it been that long?) to the D800 from the D90, and I have to say that there is an OMG moment with the D800 quite often, but honestly, I can still take amazing images with the D90 and a great lens. When I go on vacation, I still take the D90 so as not to get the D800 stolen, and I come back with some great images!
I went from D90 to D600. It's not about sharper. Both cameras will produce equally sharp images. The D600 produces cleaner noise in high ISO and has a much higher dynamic range. There are also many more features and settings in the D600 to make shooting a little bit more user customizable. But as for IQ, with proper exposure you can get about the same image with both cameras. For me, it was about higher ISO, higher DR, and full frame. I kept my D90 tho because it produced some beautiful images.
If you pixel peep at 100% the D610 wont look sharper because you are enlarging the image more than with a D90.
The ability to lift detail out of the shadows is worth the upgrade alone in my opinion. The autofocus is more accurate for moving subjects. Higher ISO shooting, cleaner files, more detail. There is nothing wrong with the D90, I used mine for years & still own it. But there is a noticeable difference in what each can produce.
Have D90, D7000 and D600. My suggestion, as was mentioned earlier, is to buy the D610, get rid of the DX glass and get FX glass, and if possible keep the D90. You may find it has it's place, though there is nothing a D90 can do that a D6x0 can't. You will see some amazing differences with a D610 under certain, but not all circumstances. I learned somethings with my D600 about High ISO that I simply could not have even learned with the D90. A fast lense makes for some interesting opportunities both indoors and out in low light. No doubt a D610 will crank up your enthusiasm.
Right now I am leaning towards buying the Nikon 24-120 F4 and the Sigma 35 1.4 ART (to pair with the D610), instead of the 24-70 as I think it *might* make a better travel kit for my upcoming family trip.
I rented the D610 for a week to compare to my D5100 (16MP, pretty darn good sensor). I don't think I really had any "wow" or "OMG" moments. I'd probably say maybe 20% of the photos were noticeably slightly better with the other 80% really hard to tell the difference.
I will try to take some this weekend.
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thx, i can see the difference when i look at 1:1 in the eyelashes. But we are comparing here two different lenses.
