[Klaus]

<div>So to analyse this new release a bit (MTFs):
</div>

<div> 
</div>

<div>mk I @ 150mm:
</div>

<div>http://www.tamron.jp/en/assets/img/produ...0mm_en.svg
</div>

<div> 
</div>

<div>mk II @ 150mm:
</div>

<div>http://www.tamron.jp/en/assets/img/produ..._150mm.svg
</div>

<div> 
</div>

<div>Not much a difference here ... but at 600mm ...
</div>

<div> 
</div>

<div>mk I @ 600mm:
</div>

<div>http://www.tamron.jp/en/assets/img/produ...0mm_en.svg
</div>

<div> 
</div>

<div>mk II @ 600mm:
</div>

<div>http://www.tamron.jp/en/assets/img/produ..._600mm.svg
</div>

<div> 
</div>

<div>Much higher resolution.
</div>

<div> 
</div>

<div>10 lp/mm = contrast
</div>

<div>30 lp/mm = resolution (30 lp/mm is a bit lowish by today's standards)
 
</div>
 

[chrismiller]

so, this on a 5d/d750 or the fuji 100-400 on X-t2?

 

Pretty similar in terms of focal length and aperture.  1Kg (54%) heavier for the 5d combo.

[JJ_SO]

Incomparable, I think. The Fuji has on APS-C much less reach, not much better speed and at the end of Fuji's FL range, which is a bit weaker, the Tamron is just sort of "in the middle".

 

Tamron made Sony a big gift.

[Klaus]

Incomparable, I think. The Fuji has on APS-C much less reach, not much better speed and at the end of Fuji's FL range, which is a bit weaker, the Tamron is just sort of "in the middle".

 

Tamron made Sony a big gift.

 

The Sony version is without VC ...

Message from the marketeers:

 

https://www.youtube.com/watch?v=dv7MmS4i...e=youtu.be

[JJ_SO]

I think, that's alright, Sony already has inbody stablisation and unlike Olympus, which can do both and add the benefits (but probably ad the disadvantage of loosing a bit of speed), neither Sony nor Tamron have a central processing unit especially for the highly dynamic VC.

 

Just realized: "Designed in Japan" can mean the same as "Apple designed in California" (and built somewhere cheaper). One point more for Sigma 

[chrismiller]

The Fuji has on APS-C much less reach

 Surely 400mm on apc = 600mm on ff?

 

The fuji is a 1/3 stop faster at the long end, but FF has roughly a stop advantage so 2/3 stop advantage to the tamron/5d setup?

[Klaus]

 Surely 400mm on apc = 600mm on ff?

 

The fuji is a 1/3 stop faster at the long end, but FF has roughly a stop advantage so 2/3 stop advantage to the tamron/5d setup?

 

The Fuji is much more light-weight and "compact" though.

[JJ_SO]

Don't compare these lenses only on their target camera factor: The Tamron you can put in front of a lot of APS-C bodies, then it's equiv. 225-900 and still speedy enough, plus crops the sweet spot out of the picture.

 

The Fujinon is only for Fuji cameras. But I agree with Klaus, it will be much easier to handhold.

[Brightcolours]

 Surely 400mm on apc = 600mm on ff?

 

The fuji is a 1/3 stop faster at the long end, but FF has roughly a stop advantage so 2/3 stop advantage to the tamron/5d setup?

FF has a 1 1/4 stop (for 1.5x crop, 1.6x crop is 1 1/3rd stop) advantage over APS-C (if the sensor tech is comparable). So a 1 stop advantage of the Tamron.

DOF wise same: f2 on APS-C is equivalent to 2 x 1.5 = f3 on FF. 

1.4x is one stop (see 1.4x TC's).

 

So, the choice is 1 stop advantage or less size/weight.

 

On reach: if you look at it from a maximum magnification perspective, FF sensors are available with higher resolutions than the Fuji sensors.

 

JoJu makes a good point about the Tamron also mounting just fine on APS-C bodies from for instance Canon and Nikon.

[chrismiller]

so my original question was which would you choose?

 

It would seem like the tamron/5d combo is good value gathering twice as much light for only 50% increase in weight.

 

Personally i'm not so sure I want to carry 2.8Kg around.