Tutorial: How to rotate raw files and save them

[Astrofriend]

Sometimes you have problems that you can't find solutions to and you push it to the future how to solve it. In my data there are photos I took already in 2013 that I accidentally have the camera's auto rotation turned on. As a result, as the mount moved during the night, the orientation of some of the photos changed.

Since then I have tried to change the rotation so that all of the raw photos will be back to a horizontal orientation again which many of the astro software require. Changing the orientation is easy in most software, but to save them in Canon's .cr2 format again I never found a solution to until now.

Here's how I solved it:
http://www.astrofriend.eu/astronomy/tutorials/tutorial-rotate-raw-files/01-tutorial-rotate-raw-files.html

I have only done this on Canon's .cr2 files. Let me know if you can use this for other cameras, Nikon, Sony etc. You have at least to change the file extension in the batch file.

/Lars

[skysurfer]

The problem is saving in CR2 (or NEF or ARW).
These formats are for camera only and not meant to be saved as a file. When you want to keep original quality, save it in TIFF or PSD (16 bits format).

[bojan]

This is easy with DPP (Canon's software, comes together with camera on CD).
BTW, DPP is very useful for other things, including post processing of AP images (stretching, curves, color balance etc.)

[Astrofriend]

@skysurfer
Yes that was the problem, but that was what I solved, how to save new metadata in .cr2 file.

@Bojan
I had DPP instaled many years ago, but was it only that I could rotate the image but not store the new orientation metadata in the .cr2 file ?

Anyway, that software only handle Canon, with Exiftool all cameras maybe possbile to rotate their raw files in. It's also a multi platform, not only windows.

/Lars

[bojan]

Everything can be saved (and reverted back later)



True...

[LewisM]

Not sure why you can't - I downloaded Canon's plugin for Potoshop, and when I try importing a RAW/CR2 file, it automatically pops up the Canon RAW handling plugin - within that, I can rotate the files, do lens corrections, change most in-camera settings etc, save them again in the altered state as a cr2, then close or import into PS.

[Astrofriend]

I'm now looking through my arcive of astrophoto data.

This one of the old images that I never processed because they were rotated, and I was not sure they will be of any interest because of the weak comet.

Here it is:
http://www.astrofriend.eu/astronomy/astronomy-photo/comets/atlas-c2017-m4/atlas-c2017-m4.html

I'm not 100% sure that the arrow point to the comet, when looking in tables I think it should be a bit more to the left.

/Lars