There are a few things you can do to improve the quality of your photos. Upgrading your camera is not at the top of the list.
1. Improve your technique.
2. Improve your post-processing
3. Learn to use an external flash.
4. Upgrade your lenses.
5. Upgrade your camera body.
The point here is simple. Spending money on gear, most especially camera bodies, does not always improve your photos. For example, this landscape photo was taken with a lowly T5 and a sharp lens. The image is a panorama and the resolution is 38MP
When I capture images for a panoramic image, I turn the camera to portrait mode. I overlap the images by one third. The Rebel T5 that I used only has 18MP of resolution. Your Rebel T7i could create an even more detailed image. I used an inexpensive Rokinon 85mm T1.5 lens.
Technique is what produced the above image. Technique is what allowed me to squeeze the image down to a 4MB so that I could post it in the forum. I wish that you could see the uncompressed file on my 4K monitor. You can almost count the rivets on the bridge when you zoom into it.
While technique was a large factor, there is one piece of gear that made the shot possible. That one piece of gear was my brand new, professional grade tripod rig. I did not buy a tripod kit. I bought everything separately.
I bought tripod legs that use a flat plate, instead of center column. The legs support over 50 pounds. I bought a tripod head that supported over 50 pounds. The most important piece of the setup is the leveling base, which is visible between the tripod head and the tripod legs. This setup cost me just over $500, which is well within what you are looking to spend on a new camera body..
BTW, the camera gear in the photo is my current landscape panorama setup. The camera is a 6D with a battery grip, and the lens is the EF 70-200mm f/2.8L IS II USM. Again, I roll the camera to portrait mode to capture a series of images for a panorama.
I feel using a high quality, robust tripod is crucial to capturing quality landscape images. Can you capture high quality images without a tripod? Yes. But, you can capture even better images with a professional grade tripod. I went heavy duty because a lighter rig can shake and vibrate slightly in the wind. This rig made a big difference in the sharpness of my Moon photos.
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As to your camera question, I would recommend the 90D for wildlife photography over the 6D2. The higher resolution sensor will allow for deeper cropping of your images. The higher frame rate of the 90D is not as useful as you might think. Your camera will not focus any faster than your lens. Not every lens can refocus at 10 fps. Not every set of camera settings can capture at 10 fps, either.
Given a choice between the 90D and 6D2 for landscape photography, I would pick the 6D2 for its' dynamic range. Ignore what the reviews say about the camera not having good dynamic range. It is still better than any APS-C sensor camera Canon sells. Although, you can capture very good images with a 90D, low ISO, and a high quality tripod. I think my above example with an 18MP Rebel T5 is proof of that.
@Waddizzle wrote:"Some reviewers have noted that the AF array in the 6DII's viewfinder is somewhat centered.... it covers more of the image area in the 90D."
Actually...the AF point coverage is probably nearly identical. This was true with the 80D and the 6D2, and it is probably still true of the 90D and the 6D2...
You be the judge...
Canon 6D Mark II viewfinder, 45-point AF array:
Canon 90D viewfinder, 45-point AF array:
These are Canon's own illustrations, from their web site.
Wouldn't matter very much to me, since I use Single Point a lot and often it's the center one.
But sometimes I like to use a peripheral AF point for an off-center composition. That can be done with either, though the 6DII will be more limited (could crop image to move subject further off-center).
Personally, I currently shoot mostly with a pair of 7D Mark II, which have 65-point AF array, similar coverage to 90D:
Image also from Canon's web site.
@Waddizzle wrote:
.....Using the same AF system on a full frame sensor body and a crop sensor body is nothing new for Canon. The 1D Mark IV and the 1Ds Mark III shared the same 45 point AF system. The full frame 1Ds Mark III had less coverage in the viewfinder, but the angle of view compared to the 1D Mark IV was arguably identical.
The 1D-series cameras are APS-H format (1.3X), which is much closer to full frame such as the 1Ds-series (1X), than APS-C format (1.6X... 80D, 90D, 7DII).
EOS 1D Mark IV viewfinder:
(Bobatkins.com illustration)
EOS 1Ds Mark III viewfinder:
(DPreview.com illustration)
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Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7DII (x2), 7D(x2) some other cameras, various lenses & accessories
FLICKR & ZENFOLIO
"You be the judge."
I think you missed my point. I am not talking aobut viewfinder coverage, as much as I am talking about angle of view through the lens. If I mounted an 80D on a tripod with a 200mm lens, the AF points will cover the same angle of view if I had used a 6D2 with the same 200mm lens.
The AF points in both cameras will cover the same angle of view through the lens. All of the AF points in the 6D2 viewfinder will fall within the APS-C sensor rectangle in the above image.
@RobertTheFat wrote:But no matter how you explain it, the bottom line is that the reviewers that Alan cited are correct. Because the AF array is the same size on both cameras, it will cover a greater percentage of the viewfinder on the APS-C 90D than on the FF 6D2.
"Some reviewers have noted that the AF array in the 6DII's viewfinder is somewhat centered.... it covers more of the image area in the 90D."
The AF array in both cameras cover the same angle of view of the image. The AF array fills more of the frame on the crop sensor bodies, but the same amount of the image is being covered.
What I find most curious about the complaint is that it usually comes from two types of photographers. The people who always use the center AF point, or the center and its' surround points. Or, it comes from people who like to move AF points around while shooting action photography, a technique which I think is far too slow for action photography. The drawbacks in latter case is probably why you have so many people using the former approach.
With the 6D2, I can have a center cluster of 15 AF points, instead of just 9. The more AF points that are active, the more data being fed to the AF system. The result is that the 6D2 tracks moving subjects, especially those moving toward or away from the camera, extremely well.
Or, I can have a center cluster of 45 AF points, which feeds even more data to the AF system. During an hour of shooting this long jump event, I took a few hundred shots and did not miss focus once. I think I had the 70-200 f/2.8, but I was using an f/4 aperture or something. I did not want face in focus with their hands and feet out of focus.
Using the center AF point with surround assist points is probably the most popular ways to shoot action photography. You really do not have time to move AF points around the screen. I would rather use the back button for [AF-OFF] to pause or reset the AF system than to start it.
I think Canon engineers may taken notice of how popular the technique of use the center with assist points is, and how just how good the 6D2 was at doing it. Or, maybe it is just coincidence. The specs of the new 1Dx Mark III include a higher density of AF points around the center AF point for better tracking of subjects.
In other words, the 1Dx Mark III will be feeding more data to the AF tracking system in the center of the frame. It seems to make a significant difference, too. I used a 7D2 and a 6D2 to shoot these long jumpers. The 7D2 would frequently lose tracking on the jumpers as they either took off or landed.
It was the sudden change in vertical motion of the subject that was throwing the 7D2 off. I should point out that I had to roll the 7D2 to portrait mode to keep the jumpers within the frame, but that should not have made a difference. I was using all AF points active in both cameras, with tracking starting with the center AF point.
Maybe, I should have reduced the number AF points in the 7D2 to just a center cluster, because it was also showing a tendency to want to track flailing arms and legs, which is when it would lose focus on the subject's body most often. No matter.
My point here is simple. Having a tight cluster of AF points in the center of the is more of an advantage than a disadvantage.
