In addition to what u/8fqThs4EX2T9 said, id also check the export settings for your jpegs.. 10mb seems a bit small for a 25mp image if you're pringtin, set the jpeg quality to 100. It might not make a missive difference, but these days, 15-20MB isn't such a big file unless you're already short on space.
Photography
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This is not a good place to simply share cool photos/videos or promote your own work and projects, but rather a place to discuss photography as an art and post things that would be of interest to other photographers.
JPEG is a compressed image format that contains less information than the raw files. This is normal.
In Lightroom, click on Export as... then JPEG, size = original (or Largest Available), quality = 100%.
That will be the full resolution image. You can verify the pixel count by right clicking on the image and selecting Properties.
So how do you get those size of a file to the client cause GMAIL won't let you email anything over 5MB.
I zip everything up, and use OneDrive with an expiring link and a password. Typically, the link is good for 90 days.
Link to a cloud folder
Its 25MB for gmail. But if you are sending a lot of images, just link a Google drive, dropbox, or other cloud.
The JPEG format is a lossy compressed file format. It can be saved at different levels of quality / compression.
PSD and TIFF are lossless, uncompressed formats.