Lighting Bug - I shut off light, the light shuts off, but there is still light. Check this picture.

I shut off the light, but I still saw light! (No torches)

Did you use stairs for the walls like in my screenshots ?
If yes, duplicate of MC-92

Any update on this issue ?

I believe there may be some issue with redstone lamps and their lighting being turned off.
Check the following tickets:
MC-10052: marked as duped of a ticket which I'm not sure it really duplicates, also, there are redstone lamps in the roof.
MC-1993, not dealt with because of modded client, but also seems to be a normally non-light emitting block that emits light after the redstone lamp is turned off.

I myself just found this issue when building a mob farm in our server (1.5.1). I have 5 redstone lamps, 3 of which I already included in a redstone circuit. Powering them and then unpowering them consistently leaves a block two blocks next to the redstone lamp (furthest away from the power source) as a lightsource, regardless of what block I place there. Replacing the block will sometimes reset the light level to normal, as will sometimes placing a torch. Also noteworthy, the two redstone lamps I haven't powered also consistently show this effect when the nearby (11 blocks away) redstone lamps are powered. Would you want me to make a separate ticket for this, or is my story enough to support this ticket?

What you say could possibly be the effect described in this comment in [MC-1018|MC-1018] thread. Further testing shows this less likely to be related (though reproducible).

The issue at our server (and what I believe to be the case in this ticket, from its short description) looks very similar to what is displayed in this short youtube movie:
http://www.youtube.com/watch?v=WJp-RS17URU

I have waded through pages of lighting bugs, but the ones above are the only ones I found and they are marked as a duplication of what now seem unrelated issues. Has anyone seen a ticket with a proper description of this individual issue? If not, I will see if I can make a simple scenario (and world download) to reproduce this bug and start a new ticket, or should we just continue in the comments here?

Is this still a concern in the current Minecraft version 1.7.2 / Launcher version 1.3.4 ? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Can confirm this for 1.7.2, launcher 1.3.4. I seem to remember having tested a logoff without success before, but now that has worked five times in a row. In 1.7.2 at least this appears to be a client-only issue. The client shows the light and the aberrant block-light levels in F3. Relogging seems the most reliable way to fix it. I can also place blocks/light in the vicinity of what seems to be the light source, and this does often seems to be the cause of the light source disappearing, but it is far less consistent. It almost seems to be that multiple of such erroneous light sources can feed into each other and they all need to be blocked off before the phantom light completely disappears.

I have copied over our witchfarm to a small creative world where the bug is reproduced. If you happen to spawn in bedrock, I hope you'll see red wool that you can follow up without damaging anything. Otherwise, there's three red arrows pointing to the location of the phantom light and ways to reproduce my observations. I hope this will prove to be more helpful than my explanations!

It's still present in 1.7.2 (I did search first, but didn't find this)
https://mojang.atlassian.net/browse/MC-41653

Still present in 1.7.4 pre-release

This bug as well as the darkness bug (dark areas that are well lit with torches etc) both seem to follow chunk boundaries.

Is this still a concern in the current Minecraft version 14w06b / Launcher version 1.3.8 or later? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Confirmed in latest snapshots (14w02a~14w06b). Happening with glowstones also. (Not the direct block light from glowstones, but the skylight is 'leaking' through them. Also MC-13574 seems related with this issue.

Dupe of/relates to MC-3961.

Is this still an issue in the current Minecraft Snapshot 15w49b or later? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Is this still an issue in the most recent versions (currently that is 1.12.2, or the latest 1.13 development snapshot 18w07c) of Minecraft?

This also happens with naturally forming obsidian from time to time as well, in which the light from when it was lava does not go away until removing the block. Tested that in 18w09a, not sure if the other lighting issues are still there though, so partially confirmed in the latest snapshot.

Is this still a issue in the latest version of the game(currently 1.13.1)?

If so, please add it to the affected versions, thanks!