Brian G
Suspended / Banned
- Messages
- 2,247
- Name
- Brian
- Edit My Images
- Yes
I recently acquired a "7Artisans" 12mm f2.8 lens for my Sony A6000.
This is a fully manual lens, with no electronic connection with the camera body, and as a result, no lens information is recorded in the EXIF file.
I've only tried this lens out once, and the results are promising.
The raw files are fine and process as normal in On1.
However, for the sake of completeness, I decided to edit the EXIF file to add the missing lens information.
I'm using a program called "EXIF Pilot" which allgedly displays all the EXIF for a particular image file - in my case this is a raw (.ARW) file.
Examining the EXIF information I find fields for "Focal Length" and "Lens Model" which initially are set to "0.00mm" and "----" respectively.
I've entered values for these parameters "12" and "7Artisans 12mm f2.8" respectively, which is enough to remind me what the shot was taken with.
EXIF Pilot partial screenshot before adjustments:
The problem that I'm having is that, after writing the changes into the EXIF file, the colour balance of the image changes.
As I said, I'm using On1 Photo RAW 2018, and in this the image becomes adjusted to 2400 deg. Colour temperature and the Purple/Green slider is pushed to full green (-150), with the result that the image has a strong green cast.
I can adjust this back to normal and restore the colour balance, but the overall exposure also looks reduced by about 1 stop.
I tried viewing at the image in Lightroom 6 and it says "Preview unavailable for this file" so it's obviously not happy with something.
The only other software I have is the beta of On1 Photo RAW 2019, and in that, the colour temperature is increased to over 9000 deg, giving an overall orange cast, which again can be adjusted out.
My conclusion from this is that editing the EXIF information (I have confirmed it's the "Lens Model" parameter that's causing the change) is somehow affecting the overall colour balance of the raw file.
I've always thought that the EXIF is mainly an ASCII text description of the image parameters, so how does editing the EXIF affect the overall image?
And why the "Lens Model" parameter?
Anyone got any ideas?
This is a fully manual lens, with no electronic connection with the camera body, and as a result, no lens information is recorded in the EXIF file.
I've only tried this lens out once, and the results are promising.
The raw files are fine and process as normal in On1.
However, for the sake of completeness, I decided to edit the EXIF file to add the missing lens information.
I'm using a program called "EXIF Pilot" which allgedly displays all the EXIF for a particular image file - in my case this is a raw (.ARW) file.
Examining the EXIF information I find fields for "Focal Length" and "Lens Model" which initially are set to "0.00mm" and "----" respectively.
I've entered values for these parameters "12" and "7Artisans 12mm f2.8" respectively, which is enough to remind me what the shot was taken with.
EXIF Pilot partial screenshot before adjustments:
The problem that I'm having is that, after writing the changes into the EXIF file, the colour balance of the image changes.
As I said, I'm using On1 Photo RAW 2018, and in this the image becomes adjusted to 2400 deg. Colour temperature and the Purple/Green slider is pushed to full green (-150), with the result that the image has a strong green cast.
I can adjust this back to normal and restore the colour balance, but the overall exposure also looks reduced by about 1 stop.
I tried viewing at the image in Lightroom 6 and it says "Preview unavailable for this file" so it's obviously not happy with something.
The only other software I have is the beta of On1 Photo RAW 2019, and in that, the colour temperature is increased to over 9000 deg, giving an overall orange cast, which again can be adjusted out.
My conclusion from this is that editing the EXIF information (I have confirmed it's the "Lens Model" parameter that's causing the change) is somehow affecting the overall colour balance of the raw file.
I've always thought that the EXIF is mainly an ASCII text description of the image parameters, so how does editing the EXIF affect the overall image?
And why the "Lens Model" parameter?
Anyone got any ideas?