Looks like I am going to be getting the 100-400L II a lot sooner than I expected.

[Sean Setters]

The Tamron is crap at 600mm, but compare the two at 400mm.

http://www.the-digital-picture.com/R...mp=3&APIComp=0

AF acquisition and accuracy is also something to consider between the two lenses. The Tamron produces good image quality at 400mm, but if it can't lock on to a target in time, then the EF 100-400mm L IS II may prove worthy of its price premium over the budget-friendly Tamron.

[HDNitehawk]

AF acquisition and accuracy is also something to consider between the two lenses. The Tamron produces good image quality at 400mm, but if it can't lock on to a target in time, then the EF 100-400mm L IS II may prove worthy of its price premium over the budget-friendly Tamron.

This is true. AF will rule supreme over IQ in many cases.

Looking at the charts I have decided the 100-400mm is not a lens I will want to own, at least yet anyway. I am selling my 300mm f/2.8L and will need something in that range.

[Sean Setters]

Looking at the charts I have decided the 100-400mm is not a lens I will want to own, at least yet anyway. I am selling my 300mm f/2.8L and will need something in that range.

What kind of capabilities/features were you looking for in the replacement lens?

[HDNitehawk]

What kind of capabilities/features were you looking for in the replacement lens?

Small, compact and the highest IQ.

Really the 100-400mm fits that bill.
But knowing myself I will end up with just two I am choosing from.
The 300mm f/2.8L II or the 400mm DO II.
It will probably end up being the 300mm.

I debated for to long between the 600mm and 500mm II, I just couldn't make the decision.

I finally made the decision and today I am waiting on the big brown truck to arrive. I went with the 500mm II because of the size and weight.
That said the 400mm DO may be to close to the 500mm for it to be a contender.

[conropl]

Small, compact and the highest IQ.

Really the 100-400mm fits that bill.
But knowing myself I will end up with just two I am choosing from.
The 300mm f/2.8L II or the 400mm DO II.
It will probably end up being the 300mm.

I debated for to long between the 600mm and 500mm II, I just couldn't make the decision.

I finally made the decision and today I am waiting on the big brown truck to arrive. I went with the 500mm II because of the size and weight.
That said the 400mm DO may be to close to the 500mm for it to be a contender.

I was hoping someone would get the 400 DO so I could see if it is a worthwhile lens or not. And I was kind of hoping it would be you because you are very thurough and particular in you assessments.

Go ahead... give it a try so I can live vicariously; and even better, find a problem so I can keep my wallet intact.

[HDNitehawk]

I was hoping someone would get the 400 DO so I could see if it is a worthwhile lens or not. And I was kind of hoping it would be you because you are very thurough and particular in you assessments.

Go ahead... give it a try so I can live vicariously; and even better, find a problem so I can keep my wallet intact.

I have a feeling that once I bought the 400mm I wouldn't find anything wrong with it. I would just end up encouraging you to buy it and your wallet would be ravaged.

My new 500 just showed up, the box had a hole punched in the side of it during shipping and the UPS guy had placed tape over it. It was at a spot that it shouldn't have hurt anything.
I think the best you can hope for is I have buyers remorse or that something is wrong with the 500mm, I send it back and try the 400mm instead. I suspect that will not happen either.