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Pages: 1
Hi there,
I am having a problem where Autopano Pro seems to fail to recognise fisheye images in certain cases. We have two different camera rigs that we use with Autopano Pro. We have a Canon 5D Mk II with a 15mm Canon fisheye lens, as well as a recently acquired Nikon D700 with a 16mm Nikon fisheye lens.
The problem I have is this - Canon fisheye images are recognised correctly regardless of if Autopano is fed a RAW or a processed TIFF, whereas the Nikon is not correctly recognised as fisheye once processed;
Canon 15mm fisheye lens --> RAW file --> recognised correctly as 15mm fisheye
Canon 15mm fisheye lens --> TIFF file (processed from RAW) --> recognised correctly as 15mm fisheye
Nikon 16mm fisheye lens --> RAW file --> recognised correctly as 16mm fisheye
Nikon 16mm fisheye lens --> TIFF file (processed from RAW) --> NOT recognised as FISHEYE - Autopano recognises it as a normal lens with a 16mm focal length only
I didn't think this would necessarily be a problem as I could still pick 'Fisheye' as the optimisation method, however Autopano had extreme trouble then stitching the file. If I used the RAW file and Autopano recognises the lens type, it stitches fine. Unfortunately I can't see any way of manually changing the lens type to fisheye? Am I missing where this is? Or is this not possible? Ideally we would like to be able to process the RAW files outside of Autopano Pro (I see this is often recommended anyway) as we have more control over White Balance and colour (dcraw sometimes does not handle the colour the best in our experience).
Any help on this matter would be greatly appreciated.
thank you kindly,
regards,
Tristan.
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Hi,
This behavior can be explained easily. So, how do we detect that some images are fisheye or not ?
- First, we try rely on our technology called LensID. It's a way to detect which lens is plugged on a D-SLR ( it's model in fact ). And then with the use of LensID.txt file, we can say if it is a fisheye or not.
For this technology to work, we need makernotes. It's the maker custom EXIF tag that are always presents on RAW files for example.
Unfortunately, all software remove this exif tag after processing the RAW, so you loose this information once you are in tiff.
- Then, if we cannot use any exif makernotes, we rely on the stored focal length. If focal length is 16 or above, it's a standard lens, if < 16mm, then we suppose fisheye. It's a bit of a hard coded rule, but it works most of the time.
So in this case, raw just works because we can use makernotes. But tiff in one case was 15mm, so considered as fisheye and in the other case, 16mm, so considered as standard lens.
This is how fisheye / standard lens detection works.
Note : you can modify the default behavior by forcing fisheye by default for all images, or just images without exif. It's in the general setting, image tab.
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Hi Alexandre,
Thanks for the quick reply. That makes perfect sense - I thought it might be that the required EXIF data was being lost in the processing but couldn't understand why the 15mm lens still worked. I didn't think to look in the preferences for a solution, but thanks for pointing me in the right direction - I've now set the correct lens type in the preferences and it's working well. I tried using the RAW files before I read your message and it did some very strange things with exposure of certain parts of the image (even though colour correction was set to off) but I guess it doesn't matter now as we can use the processed TIFFs.
Would it be possible to implement the ability to change the lens type per Group, rather than application wide? It seems a little strange that one has to force a particular lens type and focal length for all images rather than per Group, as one might be doing a number of different types of stitching in a session, not always with the same lens?
kind regards,
Tristan.
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electricart wrote:
Would it be possible to implement the ability to change the lens type per Group, rather than application wide? It seems a little strange that one has to force a particular lens type and focal length for all images rather than per Group, as one might be doing a number of different types of stitching in a session, not always with the same lens?
kind regards,
Tristan.
It is there already. Use the Image Properties icon in the Group pane:
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Thanks Mediavets. Yes, it already exists and you illustrate that really clearly as always.
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Pages: 1