Hi and welcome to the forum:
Given you are using EF-S lenses that are specific to crop-sensor bodies, I can understand your initial interest in the two cameras you mentioned. However, I would honestly say that you would be better off by investing in a Canon EOS R10 for overall much better performance particularly in low light.
The T8i is an older camera with limited shutter speed as Steve mentioned. I have owned the higher-end 90D and 80D, and honestly can say that the 90D's 32MP sensor is cramming in so many MP that it has worse noise than the 24MP 80D. That is because each photosite (which captures a Pixel of light) has to be that much smaller, and is thus less efficient at gathering light. As a general rule, the lower the MP count per unit area, the better the dynamic range and lower the noise. For that reason I kept the 80D and sold the 90D.
However, for under $1,000 you could migrate to the EOS R10, an APS-C Mirrorless Interchangeable Lens Camera (MILC) that is the current technology that has significant improvements across the board. Essentially, Canon has been winding down their DSLR lineup for some time and have not released any new bodies or lenses for years - that DSLR lineup is living on borrowed time. It is clear that the concentration and development is in the MILC R-series of cameras and lenses.
Especially for your kinds of photography, here are some examples:
1. Sophisticated face and eye focus and tracking for people. Once locked on it will just follow the subjects and keep them sharp. Focus is also more agile and more accurate, so you will be more likely to get sharp photos of the wedding party or portraits.
2. A new 24MP sensor with reduced noise and enhanced dynamic range over anything in the crop-sensor DSLR line. Unless you plan to produce extremely large, detailed Fine Art prints, this will be more than enough. Consider that the flagship sports camera, the R1, has a 24MP sensor and aimed at top-end sports, news and photojournalist whose clients will be uploading to the web, or at most printing in double-page magazine spreads.
3. A MILC gives you a clear display of what you will get as you shoot. A DSLR uses a full open aperture to give you more light to focus, but if you want to see the levels of light and Depth of Field you have to press the DoF preview button on the front of the camera. MILCS read focus and light right off the sensor, so what you see is what you get - so you should get no nasty surprises when you look at the results.
5. If you are doing video, the R10 has excellent video features.
6. The R10 has a switch to turn ON-OFF lens Autofocus. This is important as some RF lenses do not have such a switch on them.
I recommend checking out the following reviews:
Canon EOS R10 review: HANDS-ON first-looks (youtube.com)
and... 10 Reasons You Need The Canon R10 In 2024 - YouTube
or... Canon EOS R10 vs R50 vs R100: Which Camera SHOULD You Buy? (youtube.com)
To learn more about the camera see the Advanced User Guide: c006.pdf (start.canon)
You can get a refurbished body, (like new, but the box may have been opened. used for display or demo, comes with a Canon warranty) for $784. See: Shop Canon Refurbished EOS R10 Body | Canon U.S.A., Inc. If not in stock, you can select to be advised when it is available.
You can get it with the RF-S kit lens for $10 more: Shop Canon Refurbished EOS R10 RF-S18-45mm F4.5-6.3 IS STM Lens Kit |
All of your current lenses will work with the R10, you will need an EF-RF adapter, to connect them but they work seamlessly and that is only $79.
See: Shop Canon Refurbished Mount Adapter EF-EOS R | Canon U.S.A., Inc.
So for less than $900 you get a great camera with the current technology. You will need a couple of spare LP-E17 batteries though, but that should bring you in around your budget anyway.
At a later date, you can, at a later date, look at Sigma lenses for the Canon RF-S mount. These are highly-regarded lenses for their sharpness and low f/stop values that have already gained a great reputation on Sony crop-sensor cameras. Canon have opened their mount to specific 3rd-party lens makers, currently only for the RF-S lenses, but it's the sign of things to come.
SIGMA Canon RF Mount lenses | Contents | SIGMA Corporation (sigma-global.com)
cheers, TREVOR
The mark of good photographer is less what they hold in their hand, it's more what they hold in their head;
"All the variety, all the charm, all the beauty of life is made up of light and shadow", Leo Tolstoy;
"Skill in photography is acquired by practice and not by purchase" Percy W. Harris
