I've discovered a new issue (or rediscovered an old one): sometimes pics that have been rotated from their original orientation taken by the camera are not being displayed that way by the forum software (or are not being correctly rotated by Windows10). They are being displayed the same orientation as originally taken.
See this post for one example
https://endless-sphere.com/forums/viewtopic.php?f=2&t=67833&p=1250808#p1250808
in this pic:
I'm now forced to use Windows10, and it's built-in rotate function *appears* to correctly rotate the image. the image properties show the correct width (narrow) to height (tall), and it correctly shows in the image viewer in Win10, and in the file browsers, etc.
But as you can see above, when displayed by PHPBB in a forum page, it is still in it's original orientation.
The same is also true if I rotate it 180 degrees instead of 90:
which makes no sense either.
270 rotation:
is still the same as the original image as taken by the camera.
I never had this problem with WindowsXP, but I can't access that now (computer is dead) so I can't check if this is a Windows10 issue in how it rotates the image, or if it is a PHPBB forum issue in how it displays the rotated image.
In this post:
https://endless-sphere.com/forums/viewtopic.php?f=2&t=67833&start=350#p1227985
from when I was still using WinXP, an image I rotated with XP *does* correctly show as the rotated version in the forum post display,
so I suspect it is an issue in how Win10 rotates the image (which surprises me not at all).
I'm sure there's lots of image processing software out there that rotates images but I do not want to use a whole other program for it, so if someone else can confirm that this is an issue for them using Win10 as well, then I'll just go find a solution for that specific problem in Win10.
I've tried it both by using the rotate button in the image previewer, and by the rigth-click menu function for rotate-right or rotate-left. I prefer the right click method; it's what I've usually used with XP (so I don't have to wait for a program to open, perform a function, save the image, get back to the file browser, and then upload it) and can do it directly in the file browser as I am uploading images. I only need to rotate an image infrequently, so it is an ideal way to do it.
EDIT: I think I found my answer here:
http://www.howtogeek.com/254830/why-your-photos-dont-always-appear-correctly-rotated/
in that most likely Win10 is not physically altering the pixels, just changing the EXIF data, and PHPBB is probalby ignoring that data and displaying the image the way the pixels are. (whereas WinXP actually resaved the entire image in the new rotation).
But I have yet to find a solution to change the right click menu (or rotation button in previewer) physically change the pixels rather than just change the EXIF flag.