1.4 x teleconverter decision

[madencbm]

I have 5D III with 500 f4.  I tried out for days in the field first without teleconter then with my Tamron 1.4x.  I did not notice any effect on autofocus. Effect on image quality is harder to assess.

So my question is:

1). Anybody with experience believe Canon EF 1.4x III is a no brainer as upgrade

2). Best to rent and figure out for myself if  any improvement justifies the expense

3). You spent that much for the lens, just buy the **bleep** thing!

Thanks.

[kvbarkley]

http://www.bobatkins.com/photography/technical/multipliers.html

[TTMartin]

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@madencbm wrote:

I have 5D III with 500 f4.  I tried out for days in the field first without teleconter then with my Tamron 1.4x.  I did not notice any effect on autofocus. Effect on image quality is harder to assess.

So my question is:

1). Anybody with experience believe Canon EF 1.4x III is a no brainer as upgrade

2). Best to rent and figure out for myself if  any improvement justifies the expense

3). You spent that much for the lens, just buy the **bleep** thing!

Thanks.

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I use the Extender EF 1.4X III with my EF 100-400 IS II. 

There is a slight loss of contrast.

I would suggest you rent it to figure out for yourself.

My view is TCs work as long as you have enough light to keep the ISO down, otherwise you are better off cropping.

[diverhank]

In my opinion, you need to have a 1.4x extender for extra reach.  That is a given.  Unfortunately I don't have a Tamron 1.4x to compare with the Canon 1.4x but something critical as an extender, I'm not willing to compromise.  I must use Canon extenders.  Furthermore, there is the question between the Canon 1.4 II or III.  I'm using Canon version II.  If you have the 500 f/4 II then you may want the 1.4 III as it is optimized for the new lenses.

My opinion is # 1 and # 3.  My 1.4x literally lives full time with my 600mm f/4L....I lose some IQ (if you pixel peep) and a tad bit of AF speed but they are not that bad at all.  I sometimes will use my 2.0x but with the 5DIII and 7DII, I'm down to a single center point with 4 assists so AF capability is noticeably reduced.

[jrhoffman75]

If you have tried the Tamron and you don't see any negative effect would you want to spend ~$400 for no benefit?

If you are not convinced there is no benefit buy one with a return policy so you can try it out.

[ebiggs1]

What I am curious about is, you bought a ef 500mm f4L and put a Tamron 1.4x extender on it?  Seems odd, out of place.

I am a don't use extenders at all.  But I admit it does depend on what lens it is.  The 1.4x works really well on my ef 70-200mm f2.8L for instance.  But mostly I would prefer to crop in PS to get the same results.

So I am going with....

"3). You spent that much for the lens, just buy the **bleep** thing!"

There is no question an extender degrades IQ but only you can decide if it is OK.

[ebiggs1]

BTW, the Tamron 1.4x works good on the Tamron 70-200mm f2.8 lens.

[madencbm]

Thanks for all the responses.  I bought the Tamron 1.4x several years ago for another lens.  I probably should have been clearer with my question.  I intend to use a tele-converter with the 500 f4 and I realize that IQ will be degraded somewhat.  I was really wanting to know if there was any source that actually did a side by side comaprison between the two tele-converters.

Anyway, appreciate the useful imformation passed along by all who resopnded.

[ScottyP]

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@madencbm wrote:

Thanks for all the responses.  I bought the Tamron 1.4x several years ago for another lens.  I probably should have been clearer with my question.  I intend to use a tele-converter with the 500 f4 and I realize that IQ will be degraded somewhat.  I was really wanting to know if there was any source that actually did a side by side comaprison between the two tele-converters.

Anyway, appreciate the useful imformation passed along by all who resopnded.

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Absolutely, there is. Check out The Digital Picture website.  In its "tools" section look at the image quality comparison tool.  You can select two lenses and view their image quality side by side. Just select a higher focal length than the nominal maximum and the tool applies a teleconverter. 

Be be sure you are using the same f/number on each side to be fair. 

Good luck.

[kvbarkley]

Or the bob atkins site I posted above? Bob has a few other articles that directly compare TC's