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Full Version: new Tamron SP 150-600mm f/5-6.3 Di VC USD
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Quote:After a telephone conversation with the UK Tamron it looks like the US dollar cost (already published) will yet again translate directly to UK pounds one-for-one?

 

No wonder Tamron.EU has an article about "grey imports" when they overtly steal from European consumers like this?

 

By the way - I have many grey lenses and cameras and all have been perfect.

 

I think we are all waiting for a real and independant review of this lens/
 

As of now I don't see how I could review a 600mm lens. In-room I do not have enough space and outdoor there is too much air blur due to heat. Thus a real world review would be possible but nothing which involves test charts.
Could you do the test shots outdoors at night? Then the heat would be a lesser impact. Actually, what is the distance you need for testing? Was it a multiplier of the focal length?

51x or something, so that would make for more than 30 meters distance?

I have some (old 1970's) lens test charts which are calculated for 101x. How handy  Rolleyes

Actually I know the space and air quality problem. I have a telescope that I don't think is performing to its potential. Fortunately they are designed to allow the user to fine tune them.

 

Guides say to focus on a star to perform the test, but the fine adjust requires the air to be still. It isn't happening where I live. Actually, having a clear sky is a rare enough occurrence. To get around this, I bought an artificial star off ebay. That's a fancy way of saying a 50um precision pinhole. However the angular size still needs to be below some level in order to look like a point source. I calculated I'd need a minimum distance of 20m to satisfy this condition. I don't have a point I can mount the "star" 20m away from the scope... so this is a job I might never finish, just do want to as Jupiter is nicely positioned in the sky at the moment and I want to improve on my previous attempts.

Hi all,

 

Roger Cicala has published some MTF50 test results here:

 

http://www.lensrentals.com/blog/2014/01/...m-shootout
At 30 feet distance (max), this is a close focus test.

It's meant as comparison of 4 different lenses and therefore it's valid. Besides, Roger explained the test and the target. And at least, he DID test the lens Wink so one can find out the difference between the Tamron and other more expensive zooms (!)


A lot bird shots do happen in close distances, I was told. And for longer distances, the question remains if you always have a clean atmosphere for them?
I confirm that you can shot at birds at 9m/30ft, sometimes even less (I mean much less). But of course even at longer ranges, especially flocks, and that's the more likely thing for many. I don't know how many people use very long focals for landscape, in any case I do (300mm / 420mm)  Smile  and I do know I'm not completely alone. So, the 30ft test has some meaning, but I'd like to see more. Furthermore comparing with other zooms makes definitely sense and it's the first thing you'd like to known, but comparing with a prime would make sense too: you know that with the zoom you're losing something, but you'd like to know how much are you losing.

Guest

Seems like it's showing up in shops in germany, at least in various online places prices are given 1199 Euro, and listed as 1-3 days.

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