PhotogHobbyist Loc: Bradford, PA

I would suggest doing an online search for comparison reviews of each camera. That would give you a good idea of each camera's pros and cons and might even make comments regarding how well each did for photos similar to what you will take. That could give you many answers to questions you did not think to ask.

PHRubin Loc: Nashville TN USA

There are 2 significant differences between those 2 models. The number of pixels and the dimensions of the sensor.
More pixels (32MP for the 90D vs 24MP for the 750) yields more detail.
Larger size sensor (for the same generation technology) yields better low light sensitivity, but less magnification of captured image. (The 90D has an APS-C sensor (329mm²) yielding a 1.6 times greater magnification that the 750 with a "full frame" sensor (864mm²).

The low light ensitivity is not proportional to this ratio since the 2 cameras are from different times, the 90D is current, the 750D is from 2014. They both can focus down to -3 EV.
The 90D has in-body stabilization, the 750D does not (helps steady hand held shots)
The 90D can take shots faster (10fps vs 6.5fps) for getting fast moving action

For other comparisons go to:https://www.bhphotovideo.com/c/compare/Canon_90D_vs_Nikon_D750/BHitems/1502488-REG_1082599-REG

Miami39 Loc: Florida

I bought a used D750 and use it with old Nikon lenses. It is a great camera and was very reasonably priced at Adorama. If you have Nikon lenses, they probably will work on the D750. I think that the commentators on this site have good insights.

I never used Canon equipment and have basis to compare. I have been using Nikon and Leica cameras for a long time - over forty years. I also have a complete Fuji mirrorless system. Candidly, I don’t care for the output of the Fuji’s. So much for internet reviews.

John Hicks Loc: Sible Hedinham North Essex England

If you have settled on two cameras why not hire out the cameras you are interested in along with a couple of lenses and see which make suits you best.

Miami39 Loc: Florida

If you want a D750, I suggest that you buy a used one from a reputable source with a good return policy. If your Nikon lenses are not designed for full frame cameras, then you will not be able to use them. All of my Nikon lenses were from the film days and are razor sharp. I never heard of such things as sample variation at the time.

Ched49 Loc: Pittsburgh, Pa.

The D750 is 5 years older than the 90D, the Canon has more pixels, both cameras are about the same size but to me the deciding factor is the D750 has a full frame sensor. It's always a give & take when comparing two different cameras, my pick would be the D750.

amfoto1 Loc: San Jose, Calif. USA

Hi there,

Looking back at some of your previous posts, it appears you're currently using a Nikon D300s. I assume you have some F-mount lenses already, to go along with it, and possibly some other accessories.

If you like the ergonomics and handling of Nikon, then you might want to stick with them. It will be easier to learn to use a new model from Nikon, as opposed to changing brands.

That said, I don't know that you need a full frame camera like the D750. Looking at photos you've shared here on UHH, a full frame camera would have made no difference and you essentially need full frame (FX) lenses with a full frame camera, to get the best out of it. Are any of your current lenses DX (crop design)? Yes, you can use DX lenses on a D750, but the camera will want to automatically crop them and you'll end up "throwing away" most of the potential image of the full frame sensor. Instead of a 24MP full frame camera, using DX lenses on it will make it a 10MP DX camera. Even if you set the camera to not crop the images from DX lenses, you'll have heavy vignetting and will end up having to crop them later in post processing.

The D750 is essentially being phased out and replaced by the D780. That's why the D750 is selling for about $1500 right now, compared to roughly $2300 for the D780. There isn't huge difference between the D750 and D780. Possibly the new camera's greatest claim to fame is it's 4K video capability. The D750's video maxes out with HD resolution. Otherwise they are more similar than they're different. Here's a summary comparison: https://cameradecision.com/compare/Nikon-D780-vs-Nikon-D750 And here is a comparison of your D300s with the D750: https://cameradecision.com/compare/Nikon-D300S-vs-Nikon-D750

A more direct upgrade from your current camera is the Nikon D500. It's one of the best crop sensor DSLRs made by anyone and would be an excellent step up from your D300s. Here's a comparison: https://cameradecision.com/compare/Nikon-D300S-vs-Nikon-D500.

I am not knocking the Canon 90D at all. It's a fine camera, too. In fact, I'm a Canon user and I would normally recommend it highly... But any time you change brands, it can be really expensive, what with lenses and other accessories. And, the truth is, all modern cameras are capable of making great images (some of us might argue lenses are more important).

John Maher Loc: Northern Virginia

Someone posted this last week and I saved it.
https://cameradecision.com/

I am not looking for a new camera but enjoy comparing mine with the newer, better, greater -- and it seems to be very fair and objective.

As others are saying, decide what you are going to do and what you need to do it. Then, how many controls/decisions you want to make. Also if you want to do post processing and to what extent.

The advice you get here will all be good -- even that which is biased (weighted). Read it all.

Once you decide, don't look back.