Hey all, I posted here a few weeks back about some really bad CA with many of my lenses (with the exception of my kit 18-70). Long story short, my CCD was replaced for other problems and 98% of the CA disappeared. Needless to say I'm a happy camper.
I just got a used 28-70 f2.8. This lens has great potential with the d200...However, I'm seeing CA at f2.8 through f4. It disappears from f5.6 on.
The problem I had before with what I thought was CA actually turned out to be sensor blooming. This looks slightly different and more representative of real CA. I've tested it in two separate scenarios, one outside with clear skies behind some dark branches (it fairly bad there) and my standard indoor test against a strong light source (which is a great indicator since its a consistently controlled lighting situation) which came out not so bad.
So here's my question: For those that have this combination, do you see this happening? Secondly, is there anything Nikon can do to "calibrate" or adjust the lens?
I've noticed that using my older 55 Micro on my D200 that, with brighter scenes, I can get some aberrations as well. I believe it is due to light reflecting off the sensor and then back off the rear lens element. I'm told that the Digitally optimised lenses use better rear lens coatings to combat this reflection.
I don't know for sure if this is what is happening at wider apertures on your 28-70 but I do think it is a possibility.
Ok, good to know I don't have lemon. And its not outside the realm of possibility that this is happening. This lens is over six years old so you'd expect the vestiges of pre-digital to rear its ugly head. I have the 70-200, but CA is very well controlled there. and by that I mean non existent.
I considered the 18-55, but I don't like the range and I've heard some bad reports on quality issues.
I can live with some CA I suppose. i've mitigated much of it through ACR...
The Tamron 28-75mm f2.8 exibits far less CA than the Nikon 28-70 f2.8 and the Tamron is very sharp though fresh out of the box it may be soft and need to be send it in for (free) calibration. The Nikon is probably the better of the two for film though - I think the Tamron is likely to be somewhat soft on the corners on a full frame.
I also just purchased a 28-70 f/2.8 and will be purchasing a D200 in the very near future, but if this is common then I can return this lens to purchase the 17-55 f/2.8. Hmmm... I'm curious if anyone has seen this type of problem with the 17-55 f/2.8. For me, the purchase of the the D200 is a no brainer... It's the lens options that is giving me a headache.