1

Simple question:

What is the resolution of the JPG image that is embedded in RAW files shot at the highest resolution on a Canon 7D MkII body?

Backstory:

With Photos and iCloud Photo Library, it looks like I can finally leave the computer at home when traveling and just use an iPad as my on-the-spot field editor and daily family sharing device.

The one sticking point is that the iPad can't (yet, hopefully) render RAW images directly. So, when shooting RAW, it uses the embedded JPG for all local operations (while the RAW is still persisted into the cloud untouched and the computer(s) at home will render that -- all edits are non-destructive, but there is some risk that an edit won't look quite right when applied from JPG -> RAW).

If the JPG preview embedded in the RAW image is of sufficient resolution, I can live with this limitation. In the past, the JPG previews have been really poor quality (the Canon T2i, for example, looked awful).

Ultimately, I'll just eyeball it and make a decision if I can live with it. But, I'm really curious about a proper answer here.

  • 1
    I've heard that the Photogene app can render raw images. – user39791 Jun 14 '15 at 19:57
  • @JasonPolak It can, and I have the app. It doesn't fully solve the problem as it isn't fully integrated with the Photos app and the iCloud Photo Library. The transparency and ease with which iCPL works is the real motivator here. – bbum Jun 14 '15 at 23:52
  • Just be aware that applying the "recipe" from an edited jpeg to the raw .cr2 file will only have the same effect if you first convert the raw file to jpeg using the same exact settings that were used in camera. To get the most out of a raw file you need to edit prior to conversion to jpeg (when white balance, black point, white point, etc are baked in). Otherwise there is no difference than just shooting in JPEG and editing the jpeg file. – Michael C Jun 15 '15 at 3:22
6

5472 × 3648 pixels at quality=81

One of the ways to check:

exiftool -b -previewimage -w jpg canonraw.cr2

This will extract the preview from canonraw.cr2 file and write it next to the canonraw.cr2 file as canonraw.jpg. Next, run imagemagick/identify over the canonraw.jpg like this:

identify -verbose canonraw.jpg | grep 'Quality\|Geometry'

exiftool: http://www.sno.phy.queensu.ca/~phil/exiftool/

imagemagick: http://www.imagemagick.org/script/index.php

  • 1
    Fantastic; gave me a fish while teaching me to fish, too. That resolution and quality is perfectly sufficient. Thank you. – bbum Jun 14 '15 at 23:53

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.