Well, thank you Trevor! Just tryin' to help!
Actually I came across something a little while ago that might further help the original poster.
The OP was concerned about the high MP count of the R7 and how it would handle high ISO noise. Another possibility we didn't discuss is the Canon R10... It's APS-C like the 1300D and R7, but with 24MP is not as extreme an increase as the R7 (32.5MP). At under $1000 it would even leave more $ to put toward lens upgrades, if needed!
The reason I bring up the R10, which I have not used personally, is because sometime yesterday Wild Alaska on YouTube posted a video discussing the high ISO capabilities of the camera. He had done the same with the R7 and R5 cameras previously. Now he's been putting an R10 through its paces and this new video about the high ISO capabilities includes lots of sample wildlife images and potentially helpful commentary.
He also made certain comments I found interesting... Talking about the importance of at least some good light on the subject and the idea of "good noise". That's something I hadn't put a name to but had noticed with more recent Canon models. Even though there is noise in high ISO images, it is more akin to "film grain" that I saw many years ago before I shot digital, and isn't anywhere near as objectionable as the multi-colored noise of earlier digital cameras.
Let me show you an example. Below is a shot I took as a test with one of my Canon 7D Mark II when I first got them, just to see how they did at high ISO. This was shot at ISO 16000 (yes, 16 thousand... not 1600). Lens was my EF 100-400mm "II" at 158mm and f/5 (wide open), hand held at 1/125. Subject is my poor cat, who serves as a test subject a lot. Lighting is minimal... a window without direct sunlight about 6 feet to the right and even further away a single 60 watt light bulb. No flash. First image is the largely uncropped image with default level of noise reduction converting the RAW in Lightroom. The only other tweaks I made to the image were to add contrast because the dynamic range got "pinched" a bit, as can be expected at very high ISO (this illustrates image illustrates how that can be corrected to bring back much of the shadow and highlight detail). 2nd example is an extreme crop from the same image to show that, yes, there is noise. But in my opinion it is what Wild Alaska is calling "good noise".
Please ignore the watermark on the above images. I no longer work with Exposure Manager. They went out of business (owing me a fairly large sum of money, I might add!).
Also keep in mind above shots were done with a now eight year old camera. The 7D Mark II was introduced in 2014. While the 7D Mark II has a generation newer sensor and two generation newer processor than your 1300D, the R7 and R10 both are brand new models, released just a few months ago, with even newer sensors and processors! Your 1300D uses a Digic 4 processor, while the R7 and R10 both use five generation newer Digic X (Canon skipped over Digic 9 for some reason, going from Digic 8 to the current Digic X). Processor power and programming effect high ISO performance significantly.
Regarding the R10... Of course, as you might expect with a less expensive camera you give up some things, comparing the R10 to the R7. As mentioned, it's 24MP instead of 32.5MP. it also doesn't have in-body-image-stabilization (like the R7 and R5 have). And it has a single memory card slot instead of dual slots in the R7. And the R10 has a 1/4000 top shutter speed (vs 1/8000 in R7). The R10 also uses a smaller battery which gives fewer shots per charge than the R7.
What's amazing though is the ways in which the more entry-level R10 matches the R7! Both cameras use essentially the same ultra high performance AF system (similar to the top of the line, $6000 R3's!). I think it's fair to say that the "smart" AF systems of these latest mirrorless cameras are game changing for anyone shooting active subjects like sports and wildlife. They can not only track faces, they can focus on vehicles and eyes! Once you learn to use it, either of these cameras will simply blow away the rather antiquated AF system you use now. Both cameras can take 15 shots per second with their mechanical shutter. With their electronics shutters the R10 is a little slower, but still manages a very respectable 23 frames/sec. compared to the R7's 30 frames/sec.
The R10 doesn't have the same level of sealing for dust and weather resistance and someone told me it doesn't close it's shutter during lens changes, the way the R7 does to protect the sensor from dust. The R10 also uses a slightly lower resolution rear LCD screen. But that rear LCD is a fully articulated Touch Screen on both cameras. The R10's viewfinder has the same resolution as the R7, but it doesn't have the same level of magnification, so is smaller. (If possible, check the R10's viewfinder out in store because some people feel it's too small, especially if they wear glasses while shooting... but it might be fine for you if you are accustomed to 1300D's.)
The R10 has a built-in, pop-up flash, which the R7 and R6 both lack. (I nearly forgot, because I never use built-in flash: Too weak, too prone to red-eye and too much drain on the camera's power supply.)
The Photons to Photos website I linked in my earlier response for comparison doesn't help us with the R10 because they haven't tested it yet. Go search for "Wild Alaska Canon R10 ISO" on YouTube if you want to see how the camera handles high ISOs in real life. You also can see how it compares with the R7 in some of his earlier videos, if you wish. (Note that R7's higher MP makes for more "croppable" images.) I don't believe he has used the R6, but he has used the R5 quite a bit. And, by the way, he makes regular use of DXO PureRaw for all his images. You can find his and other peoples' examples of how well that works on YouTube, if considering it.
Cheers!
***********
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
