Teleconverters

[Tascosa Slim]

I currently own and use a Canon T3i 600D camera and use a Tameron SP 70-300mm telephoto lens with the camera. I am interested in adding a teleconverter to this arrangement.

1. Are both the Canon 1.4x EF Extender III or Canon 2.0x Extender III compatible with the camera and zoom lens noted?
2. Are both the Tameron 1.4 SP AF PRO or Tameron 2.0x SP AF PRO compatible with the camera and zoom lens noted?

Thanks!

[Geoff F]

I'm not sure about that particular lens but basically; Canon converters are often a problem because they will only physically fit a rather limited number of lenses.

Any x 2 converter will lose autofocus unless it is used on a F2.8 lens. So there will be an issue with any F4, or narrower, minimum aperture lens. Possibly works on higher spec bodies?

Converters can cause some quality loss on most of the cheaper zooms, particularly the x2. Best used with prime lenses or some high quality zooms.

[loosecanon]

As said above the canon converters only fit some lenses. Essentially the design has an element that comes forward and ends up near the exit element of the lens being used, so the accepting lens needs to allow this. This arrangment helps the optical result, but limits lenses it can be used with.
Most independent converters are more flexible because they don't get so close to exit element of the lens used. Hence they can usually be used on more lenses, though some are sold as "matched" to particular lenses. Tamron used to have a good name for the quality of thier converters, may still have , I don't know.
On a crop sensor the decrease in quality is less noticable when a full frame lens is used. I use a Kenko pro 1.4 converter on a Canon 70-300 which doesn't accept Canon's own converter, and stopped down it provides acceptable results.
Unlike the days of film, when cropping was more difficult unless one printed ones own images,the need for a converter is less, however it is a judgement call - less cropping (with converter) or better image quality (without converter) which may allow more cropping.

[William W]

I currently own and use a Canon T3i 600D camera and use a Tameron SP 70-300mm telephoto lens with the camera. I am interested in adding a teleconverter to this arrangement.

It is not the best solution to use any teleconverter with that lens when using an EOS 600D because (in theory)with a x1.4 you will will lose Auto Focus when the lens zoomed at about or beyond about 100mm; it is possible that you will have no AF at all; or it will be intermittent; or vaguely hunt.

With a x2.0 you should have no AF at all.

Also, in many shooting scenarios Manual Focusing can be quite difficult.

When shooting in good light and at lower ISO’s, a more elegant solution than using a x1.4 would be ensure you nail the exposure correctly and to crop in post production to attain the desired equivalent Field of View.

If you want to get to FL = 600mm, then better to buy another lens, though using low ISO and at small enlargement sizes cropping the image in Post Production to get the equivalent Field of View of a 600mm lens can be suitable for many applications, for example web page images and small prints, again provided the light is good and the correct exposure is nailed.

*

1. Are both the Canon 1.4x EF Extender III or Canon 2.0x Extender III compatible with the camera and zoom lens noted?

Yes. Both the Canon x1.4 and x2.0 Extenders EF MkIII (and all other model Canon Extenders EF) are compatible with the EOS 600D.

No. The Tamron 70-300mm f/4-5.6 Di VC USD is not compatible with either of the Canon x1.4 or x2.0 Extenders EF MkIII. Moreover those extenders will not physically mount to that lens.

2. Are both the Tameron 1.4 SP AF PRO or Tameron 2.0x SP AF PRO compatible with the camera and zoom lens noted?

Yes. Both the Tamron x1.4 and x2.0 SP AF PRO converters are made in a Canon EF mount and those are made to be compatible with an EOS 600D. But Canon will not guarantee compatibility with any 3rd party lenses or extenders/converters.

No. The Tamron 70-300mm f/4-5.6 Di VC USD is not compatible with either the Tamron x1.4 or x2.0 converters. But it is possible that the lens might mount to those converters and as a consequence provide compatibility limited to manual focus only.

WW

[JR1]

I currently own and use a Canon T3i 600D camera and use a Tameron SP 70-300mm telephoto lens with the camera. I am interested in adding a teleconverter to this arrangement.

1. Are both the Canon 1.4x EF Extender III or Canon 2.0x Extender III compatible with the camera and zoom lens noted?
2. Are both the Tameron 1.4 SP AF PRO or Tameron 2.0x SP AF PRO compatible with the camera and zoom lens noted?

Thanks!

Many sites have compatibility charts on them, as will the tamron site

http://www.wexphotographic.com/blog/...tibility-chart

[Tascosa Slim]

Gentlemen:

Thanks for your replies to my question on teleconverter compatibility. Based on these replies I will not be incorporating one into my lens kit in the near future. Looks like I'll hold off and save my coins for a different solution.

Again, many thanks!

[jcuknz]

You might find that while such cameras have auto-focus problems when using Phase Detection they do not when using Contrast Detection. I do not know your camera but I have no problems with CD at what appear from what I have read quite impossibly small apertures resulting from combinations. So perhaps if possible to test the rig before the buy it is worth investigating.
My experience was that it was very difficult to stop CD.AF finding focus when I tried, and it was quite fast