Kenko extender for Canon EFS mount advice: I have a Canon Rebel EOS t2i camera, 18-55mm kit lens, 50mm f1.8 lens, and 55-250 IS f 5.6 lens. Mostly I enjoy taking photos of this and...

BlueMorel Loc: Southwest Michigan

I have a Canon Rebel EOS t2i camera, 18-55mm kit lens, 50mm f1.8 lens, and 55-250 IS f 5.6 lens. Mostly I enjoy taking photos of this and that close to me or, when on vacation, landscapes. However, I would like on occasion to try some BIF or BIT (in trees) or other wildlife photos without spending a lot.

So I've been looking for an extender for my 55-250mm lens, and B&H lists Kenko extenders for the EFS mount, both 1.4x and 2x. I'm thinking I want the 2x . Am I on the right track? Does anyone have experience with these?

Price is a big part of my choice, so no use telling me I need a FF camera and large expensive prime lens.

Anvil Loc: Loveland, CO

I’m pretty sure you will not be able to auto focus with either extender, using that lens. I believe that camera requires a max aperture of f/5.6, in order to auto focus. Your lens is f/5.6, but if you were to add a 1.4x extender, you would lose a full stop, meaning you would be required to use manual focus. That can get tricky, with BIFs. Not impossible, but tricky.

CHG_CANON Loc: the Windy City

Third-party extenders (also known as tele-converters) may fit to your EF-S lens, but the loss of 2-stops of light will disable the autofocus on all Canon EOS DSLR models where 2-stops above f/5.6 is f/11. Don't waste your time nor money on this configuration. Your T2i won't autofocus at f/8, so the 1.4x is also not a viable option for birds in flight photography.

Bridges Loc: Memphis, Charleston SC, now Nazareth PA

BlueMorel wrote:

I have a Canon Rebel EOS t2i camera, 18-55mm kit l... (show quote)

Kenko makes very good extenders. In the 1.4 they make two models, the PRO 300 is the better one with an extra element -- I have used it with several lenses and I think you can get away with using it on your lens. I've used it on a 150-600 and at 6.3 it will still auto focus. The 2.0 might be a challenge though and most likely would only work on the brightest of days. Good luck with your BIF photos. Patience and shooting in bursts of 10 to 12 shots at a time really help. A good tip I picked up recently is that if you want to shoot a bird coming toward you, make sure you have your back to the wind. Birds take off and land like planes -- into the wind.

Anvil Loc: Loveland, CO

Were you able to get a Canon T2i to auto focus, using the 1.4x extender? I thought that body was too old to be able to auto focus at an aperture smaller than f/5.6. I could be wrong.

Blurryeyed Loc: NC Mountains.

BlueMorel wrote:

I have a Canon Rebel EOS t2i camera, 18-55mm kit l... (show quote)

Save your money for a good used lens, believe me you will be happier, you can buy a Canon 400mm prime in the $700 range that will knock the socks off of that 250mm zoom of yours.

BlueMorel Loc: Southwest Michigan

Anvil wrote:

I’m pretty sure you will not be able to auto focus with either extender, using that lens. I believe that camera requires a max aperture of f/5.6, in order to auto focus. Your lens is f/5.6, but if you were to add a 1.4x extender, you would lose a full stop, meaning you would be required to use manual focus. That can get tricky, with BIFs. Not impossible, but tricky.

Thanks! Perhaps I'm overreaching thinking of BIF. I understand about the effect of the extenders on light. I never would have thought that my camera's autofocus wouldn't function effectively at lower light/higher f-stop. I assumed it would compensate. Hitherto my subjects have been static for the most part.

BlueMorel Loc: Southwest Michigan

Thanks, ChgCanon. I'm glad I posted this question. I am now a little closer to understanding BIF photography, ir at least where I need to start learning. I'll save my $$ until I study more.

BlueMorel Loc: Southwest Michigan

Bridges wrote:

Kenko makes very good extenders. In the 1.4 they ... (show quote)

Thanks for the feedback. The Pro model is what I looked at - it is the only one that lists an EFS mount. The reviews i found are 3 to 7 years ago, but ithink they were EF mounts.

BlueMorel Loc: Southwest Michigan

Blurryeyed wrote:

Save your money for a good used lens, believe me you will be happier, you can buy a Canon 400mm prime in the $700 range that will knock the socks off of that 250mm zoom of yours.

Thanks! You and the others talked me down. Time to put my Starbucks money into saving for that lens! Meanwhile, when the weather gets better, I'll rent one for a week and try it out.

CHG_CANON Loc: the Windy City

You'll get advice all over the place ... I'd look at the older / original EF 100-400L IS, the EF 400 f/5.6L, and the EF 300 f/4 IS. They're running in the $700 to $800 range, used at KEH. You might do better in a private sale, here on UHH or via ebay. Given the age of these lenses, with the 400 and 300 still being current, you can probably rent relatively cheap and get a sense of the zoom vs prime and focal length you desire.

BlueMorel Loc: Southwest Michigan

CHG_CANON wrote:

You'll get advice all over the place ... I'd look at the older / original EF 100-400L IS, the EF 400 f/5.6L, and the EF 300 f/4 IS. They're running in the $700 to $800 range, used at KEH. You might do better in a private sale, here on UHH or via ebay. Given the age of these lenses, with the 400 and 300 still being current, you can probably rent relatively cheap and get a sense of the zoom vs prime and focal length you desire.

Thanks again, Paul. I'll google those lenses and will rent before buying for sure. Lots to think about. Great tips from everyone and my knowledge takes another forward leap.

CHG_CANON Loc: the Windy City

BlueMorel wrote:

Thanks again, Paul. I'll google those lenses and will rent before buying for sure. Lots to think about. Great tips from everyone and my knowledge takes another forward leap.

When you get north of $800, you also should consider Tamron or Sigma zooms as well, typically covering 150-600mm. The newest models are highly regarded, but also more expensive. The used and / or older models are more price competitive, but may not be as sharp as the used L-series models. I mentioned the 300 f/4L as this is highly regarded and can be extended to 420 with a 1.4x and retain IS and AF on your EOS body. You might find a prime too limiting, but with the extender you have two excellent primes when you have needs in these two focal lengths.

Architect1776 Loc: In my mind

BlueMorel wrote:

I have a Canon Rebel EOS t2i camera, 18-55mm kit l... (show quote)

I agree with others as to most likely AF will not work too well if at all with an extender. You need an effective aperture of f5.6 which with the extender you will not have. All else will work just fine but the AF will be lost.
This is not unique to your camera either. Some newer cameras now go to f8 but not all of them either.

jerryc41 Loc: Catskill Mts of NY

I have the Kenko Pro 1.4, and I'm satisfied with the results.