P: Camera Raw: Canon R5 Raw images are underexposed

Having the same issue!! Every previous canon camera body I’ve had have been close enough the same to the camera preview that it was not obvious.. not it is significantly darker!!!

Yes exactly, a rendering adjusted for brightness.
The exposure is what it is.

The LrC bug means the R5 CR3 image rendering needs +.8 stop to match in-camera appearance of same image.

Thank you for acknowledging this bug. 🙂

Thank you! Please get a software update to us as soon as possible to fix this issue.

We just photographed a wedding using three Canon EOS cameras (5D Mark IV, 1DX Mark II and new R5) and imported just over 10,000 RAW files (multi-day, two photographers) as usual into LR Classic as we have done for many years with success. I can confirm that every photograph from the R5 initially looked fine when LrC was reading the internal JPG made in camera, but once LrC made its own 1:1 previews, every R5/CR3 image was presented around 2/3 stop too dark/underexposed and looked very flat (in dire need of some color saturation). I also note that LrC applied ZERO noise reduction whatsoever to CR3 files on import and that's unfortunate as it needs a bit of NR as usual to make images look best. The CR2 files from the other two cameras looked perfect as usual so it was easy to pick out the unfortunate R5 CR3 rendering. I believe there is an issue here and we anxiously await an update to LrC to address this as we live or die by LrC in our business. Many thanks.   Denis Reggie - Atlanta

I shoot raw because it has additional latitude over the JPG image, but the camera's rendition of what the final JPG will look like is very good. 

Exactly, Ideally you want to stick with the raw data. The JPEG engine that processes the raw massively clips and compresses highlights. We often don't when editing the raw. This compression can clump midtones as much as 1 stop while compressing shadow details! People incorrectly state that raw has more highlight data but the fact is, the DR captured is an attribute of the capture system; it's all there in the raw but maybe not in a camera proceed JPEG.

A raw capture that's 10 or 11 stops of dynamic range can be compressed to 7 stops from this JPEG processing which is a significant amount of data and tonal loss! So when we hear people state that a raw has more DR than a JPEG, it's due to the poor rendering or handling of the data to create that JPEG. The rendering of this data and the reduction of dynamic range is from the JPEG engine that isn't handling the DR data that does exists as well as we can from the raw! Another reason to capture and render the raw data, assuming you care about how the image is rendered!

And with ideal exposure for raw, you can better deal with DR as outlined. 

Now Rikk states this rendering is a bug that will be fixed, but again, the exposure is what it is, so in the meantime, adjusting the rendering brightness to compensate should be a temporary fix. 

Lets hope this won't take half a year and longer like other acknowledged bugs. Could be worth betting what happens sooner, Canon resupplying the R5s or Adobe fixing something. 😄

I think you're posting in a more intricate, detailed level than I am - which is Ok because I'm learning a little something here too. 

I shoot raw because it has additional latitude over the JPG image, but the camera's rendition of what the final JPG will look like is very good. 

I have actually made a preset "tweak" that includes about 1/3 stop increased brightness, a little adjustment to the contrast, and some tweaking of the colors in the calibration panel to try to mimic, as best as I could, what my camera-produced JPG image renders. It helps having that little color checker panel as well.

Yes, I agree, it's all somewhat subjective. What it actually looks like - vs - what you think it should look like, what you remember it looking like, and what Canon, Adobe, and the Dell monitor think it looks like - well, it's a lot align.

Thanks for the insights and the links.

 it seems like Adobe isn't accurately rendering the exposure on-screen and thus requiring additional adjustments.

There is nothing ' accurate' here. The raw is essentially a grayscale file. It has to be rendered into RGB and that's done based on the current settings. 
You use say Adobe Standard profile, you get one rendering and a different rendering doing nothing else but picking a differing DCP profile. Or a slight adjustment of WB etc. Nothing here is accurate, it's all subjective. 

I noticed that if I instead use a camera-generated JPG, the exposure retains that 1/2 to 2/3 stop greater brightness.

Again, the camera generated JPEG is just another subjective rendering of the raw data produced by a machine, not a human. It isn't any more or less accurate than any other preferred (subjective) rendering and it isn't based on the exposure of the raw. 
You could make a default adjustment of /2 to 2/3 stop greater brightness, open the raw, it would look as you desire. And that's probably what you should do but recognize again, the actual (optimal) exposure is still unknown. You must view the raw data to know about that attribute of the raw data. 

Of course, you lose the dynamic range benefits of the RAW file that way

No, you lose it by not exposing the data ideally in the first place! And that toothpaste is out of the tube by the time you're in LR/ACR. See:

https://www.rawdigger.com/howtouse/calibrate-exposure-meter-to-improve-dynamic-range