TaoTeJared said:
El_Pickerel-
I think you have a mixture of a odd light source, JPG/De Noise, over saturation and some reflection from the filter and probably some smoke or dust that diffuses and spreads the back light. I think you just stumbled upon that perfect mix of everything that can happen with any lens. If it was the lens only, the light on the left would have done something similar. I think any lens would have reacted the same or similar, Nikon or not. The Tokina IMO is 100x better than the 18-105.

Again, there was no filter on this lens. As for the other point light in the shot not doing the same thing, I think that could be due to that light being of a single colour instead of white light. Everything I shoot is in raw format, and that behaviour is present in the raw files. Here is another shot, indoors, with the same effect. There is less colour around the fluorescent lights, but I think that could just be due to the cooler colour of those lights (not as much red / warm colour to split off)

There is like 6 total versions. 2 of the 28-80s but there is probably not much difference. Tokina's CAs are generally purple. It's not CAs but it looks like reflection or diffraction from the filter (from both shots). I do not think it is the lens but not to say you were at just the right angle for that to happen.

Due to Tokina's coatings I have found there is more reflection than other lenses. I have found you really need a higher end filter that is specially designed to eliminate reflections. I use "Hoya HMC Super" and it works well.

El_Pickerel-
I think you have a mixture of a odd light source, JPG/De Noise, over saturation and some reflection from the filter and probably some smoke or dust that diffuses and spreads the back light. I think you just stumbled upon that perfect mix of everything that can happen with any lens. If it was the lens only, the light on the left would have done something similar. I think any lens would have reacted the same or similar, Nikon or not. The Tokina IMO is 100x better than the 18-105.

Just from one picture, I wouldn't worry that the lens is not good. A good habit with any lens is to make sure back light sources are hidden and not shoot them straight on.

noxin - in your picture that is definitely the filter causing that. B+W or not, that is the filter for sure. I have seen that on my older filters without the advanced coatings and anti-reflective coatings that will cause the "Prism" effect.

Filters really can make a huge difference. For the "high end" filters, you generally can figure about $1-1.50 per mm. So around $70. I use either Hoya (SMC) Super Multi coated or the Pro1D filters. Never anything less. Those are the cheapest, highest end filters I have found. Kenko has some, but the actual good ones are in the $140 range.

I know a lot of people like B+W filters but I can't stand their terrible "naming" scheme where you can never know which version you are getting just by the name. In the past I have always had problems with color separation (like noxin's photo) and reflections. A friend of mine loves them, but he spends $180 for each 77mm filter.

Mine is the 28-80, not either of the 28-70s.

I have the Tokina lens also but never noticed that. Can't say I have tried to make that happen either. There are different versions. What version are you using?

http://nikonglass.blogspot.com/2009/11/tokina-at-x-pro-28-70mm-f26-28.html

No filter present... even the UV filters I do use don't do anything like that!

noxin said:
you know, I have this same lens and it did it to me also:

Maybe its a coating or something, but I do have a good B+W UV Haze filter on it. Overall I do like the lens, especially for the money.

Did you resolve this behaviour in any way? Good to know I'm not the only one I guess.

you know, I have this same lens and it did it to me also:

Maybe its a coating or something, but I do have a good B+W UV Haze filter on it. Overall I do like the lens, especially for the money.

Just 1 question... : Is there a (UV) filter attached to this lens ? cause this looks to me a reflection from the inside of the lens against something in front of the lens ( Filter ?)

I recently acquired one of these lenses for cheap, to serve as a fast aperture midrange zoom for a while. I used this extensively over a weekend-long retreat. I'd checked what few reviews I could find and knew it would not be as sharp as the Nikkor 24-70. While it is an AT-X Tokina and the build quality is great, I was not prepared for the issue I found with it. Below is an extreme example, shot at high sensitivity by firelight. It does however very well showcase what is happening when any light sources or other extreme contrast is present in the shot:

(Processed in Lightroom, with the luminosity turned all the way down in the blue and purple and green channels to darken some of... that)

For all but the lowest lighting (or need of shallower DOF) I think I am better off using the 18-105mm kit lens. I don't think I could sell images from this lens that include light sources or really heavy contrast. Landscapes or outdoor / ambient light stuff wouldn't be so bad, just make up for some of the sharpness by stopping down and/or increasing it in post, but I think a Nikkor 24-70 or 17-55 might be in order if I am going to take any paid work very soon.