Question re: Tamron 70-200 vs. EFS 55-250

[Pauly_6_String]

Just got the 70-200 and was under the impression I would get more focal length from it due to 1.6 crop factor.  It was told to me that the EFS is designed for APS-c and would be 250mm max compared to Tamron 320mm cropped.

Pic I just took to test this did not shwo this to be true.  The Tamron 70-200 was a bit widerthan the 250mm EFS lens.

Did I get bad info?

thanks

[ebiggs1]

"Did I get bad info?"

In a word, yes, you did.  There is no crop factor for a lens.  200mm is 200mm and 250mm is 250mm no matter what camera it is mounted on.

Crop factor is such a misunderstood term, I wish it was never started.  It is the camera that has a crop factor.  Meaning a 200mm lens will appear like a 320mm lens would have looked like an a FF 35mm film camera. So, the Tamron at 200mm reacts like a 320mm lens and the Canon 250mm lens reacts like a 400mm lens. Keep in mind this is only true for people comparing them to a FF DSLR or 35mm film camera.

You had a 250mm lens and went down in FL to a 200mm lens in reality you lost 50mm of telephoto.

[Pauly_6_String]

Thank you for your reply.  I’ve just compared the two lenses with a wide open and full zoom shot.  The increased image quality of the Tamron will far outweigh the loss of 50mm.  

[ebiggs1]

"The increased image quality of the Tamron will far outweigh the loss of 50mm."

I agree, if you got the Tamron SP 70-200mm f/2.8 Di VC USD G2 Lens?   Very nice lens.

[ebiggs1]

A better way to understand this is to look at Angle of View, AOV. A 200mm lens has approx a 12 degree AOV.  Since the sensors are smaller on a crop body this causes a slight telephoto effect to take place. If you put a 125mm lens on a Rebel and a 200mm lens on a 5D Mk IV the resulting photos would look the same because the AOV coverage each sensor saw was the same.

[Pauly_6_String]

I did get that lens. I think it’ll be a good one from all I’ve read about it.

[ebiggs1]

As of a few months ago I am Tamron-less.  I sold all my Tamron lenses but if I could not have the  Canon EF 70-200mm f/2.8L IS II USM Lens, a lens I absolutely love, it would be the Tamron SP 70-200mm f/2.8 Di VC USD G2 Lens.

I still have the Sigma copies but they are not as good as the Tammy G2 and very much less than the Canon. All the G2's are next best if you can't go Canon.