There's two new bugs I have. The shadow resolution changing bug is something I had before patch 1.5 though. The invisible sun bug I just noticed after patch 1.5.

The shadow resolution changing bug:
What this bug basically is, is that the shadow resolution changes in-game by itself. I have 4096 shadow resolution in the .ini, but with this bug it can suddenly become 1024 in-game (it's still 4096 in the .ini though).
The shadow resolution changes depending on how I move my mouse. For instance if I look down on a tree shadow or a rock shadow on the ground it's 4096 shadow resolution and good, but if I move my mouse just very slightly in a (what it seems) random direction, suddenly the shadow resolution changes to 1024 (which I can tell because it's much more blocky).
My FPS isn't affected by this shadow resolution change, strangely. This bug is quite annoying and noticable, because of how big the difference is between 4096 and 1024 shadow resolution.
Here's a demonstration:
4096 and good: http://oi40.tinypic.com/2dlm0pi.jpg
1024 after moving mouse slightly: http://oi41.tinypic.com/58d45.jpg
Edit: after testing more I've found out that it's not 1024 that it changes to. It actually changes to something between 4096 and 2048.

The invisible sun bug:
When I first started the game with patch 1.5 the sun looked fine and normal. But once I fast travelled to a new location so that the weather was different, the sun became invisible.
I can see the sun glare texture, but not the actual sun texture. It's simply not there.
http://oi39.tinypic.com/2416slx.jpg


What I've tried to do:
- Regenerate a new default .ini.
- Verify game cache
- I have no mods installed

Re: shadow changing resolution bug - this has been around forever. If you watch carefully the E3 videos with Todd Howard (the one with the 30 minute gameplay preview), you can clearly see this happening early on in the video.

Start watching from 00:43 of this video. Watch in fullscreen and 720p to see it much better. You can see it clearly when he says "... all the little details like this plant here"

http://www.youtube.com/watch?v=oSL-r9AIEEU

Ah, that's strange and bad. But why did I start to notice it just recently? It happens really often when looking down on shadows. I don't remember noticing it before...

Can someone else confirm that they have this shadow resolution bug?

I've experienced the shadow resolution bug since 11/11/11.

Another shadow oddity I noticed since 11/11/11 is that tree shadows stop animating when you're looking at them from a certain angle or distance. Try the little guard campfire just outside of Riverwood during the morning to noon. There's a bunch of tree shadows being casted against the gray rocks/boulders near that campfire. The shadows will animate with the trees if you're not standing too close to the rocks.

Go near the rocks and suddenly the shadows stop animating.

Confirmed, I have the same bug. When I move the mouse slightly, the shadows will change suddenly to low res, then change back if I return to the original position. I have had this since day 1 and never managed to eliminate it. It doesn't seem to be always present as far as I can tell, I just notice it at random once in a while.

I have my iBlurDeferredShadowMask at 7, so the shift isn't as noticable as the shadows are quite blurry.

Edit: Just noticed another post about the tree animation not working from some angles. I did have that problem and fixed it by playing with my nvidia settings. Pretty sure it was disabling Transparency AA that did it, but don't quote me on that. It was back when I first started playing. Something to try anyway.

Is there a performance hit with tweaking up the DeferredShadowMask setting? Mine is currently set at 1, but I might tweak that a bit higher to try and take away some of the Space Invader feel I get with the medium shadows settings.

I know for a fact that trees stop to animate when your FPS hits lower than 30. This is not a bug, but a means of trying to save performance. I'm not sure if this is your problem though, but you can look at your FPS while this is happening though to confirm whether it's another problem or not.

Darn, so it's a general issue for everyone. I still find it so strange that I didn't notice it before. I guess I never payed much attention to the shadows, which is no wonder since they're not exactly a beauty to look at *cough* mario-pixel-shadows. "Glad" to know that I'm not the only one, at least.

Performance hit should be quite small, according to: http://hardocp.com/article/2011/11/23/tweaking_skyrim_image_quality/2
Beware though that blurring the shadows will also strongly blur out the trees if you have tree shadows on, and make the trees look fuzzy/smudged out.

That makes sense. Fixed my tree animation by getting my framerate up.

Always kind of wondered if the settings had something to do with the shadow problem, The primary and secondary shadow settings in the ini have no effect, but maybe Skyrim has two shadow maps and one of them is hardcoded to 1024 within the game and just shows up once in a while because of a rendering bug of some kind? totally guessing here as I'm no expert.

iShadowMapResolution=4096 iShadowMapResolutionSecondary= <--changing this no effect
iShadowMapResolutionPrimary= <--changing this no effect.

Yeah I had the secondary and primary resolution on 1024 and 2048 so I thought that could be the reason first when I noticed this changing resolution bug. But changing all shadow values to 4096 did nothing.
I also found out now that the shadow doesn't change to 1024, nor to 2048. It actually changes to something between 4096 and 2048.

I also noticed that this shadow changing bug only happens when you have 4096 shadow resolution in the .ini. If you choose 2048 or 1024, the shadow resolution won't change in-game, but also look a lot worse all the time.

Awesome--cheers. I don't have tree shadows on, so I should be good there. I'll make those Space Invader shadows slightly more palatable yet.

The invisible sun bug:....about that.

Holler when you find your Sun......Mine seems to have gone MIA also....lol

I can load an earlier save and the sun is there, but when i load my current save there is no sun. I even uninstalled some mods that touch the sun, still MIA. In the earlier saves it is there modded and not.

time in the game is at "Suns Height"....lol

Hmmm, it looks like in Skyrim not the Sun makes days bright, then why to worry about that? If the sun doesn't do its job, IMHO maybe better to remove another useless object from the game for performance sake?

Not sure if this is a joke or a troll.

Anyway, so it seems I'm not the only one with the sun problem there?
I hope they fix this. I'm not going to play a game without a sun. Looking at sunsets and sunrises was one of the things I enjoyed the most in Oblivion.

No man, I'm not trolling. My PC isn't good enough to run Skyrim even at High settings (ultra is a dream). I play at low settings, and no sunrises or sunsets for me. Only thing I can enjoy is killing bandits, trolls, dragons, altmers etc... and I was kidding in the prev post.

I will be looking into this deeper this weekend...Yes my Sun IS gone in my current save (level 53)...but a save from level 3 its there?....didn't check any more saves yet...will start a new game and check that also. First thing tho I am going to undo all my mods. Weird that the Sun Flair (modded and not) is there?? Sun .dds is installed by 2 different mods that I know of....