I am planning a wildlife trip. I want to be able to take photos of far away objects and still have all the detail. I currently have a Canon 650D and my longest lens is 70-300mm. I am busy saving for this trip and a converter or lens. What considerations should I take into account for each option?

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    Without some specific criteria by which to judge 'best', you're just going to get opinions. A 500mm f/2.8 will give you the best image quality, but it's probably out of your price range. A 3rd party super zoom is more affordable but somewhat slower. A teleconverter is the cheapest solution, and fits in your pocket, so might be the "best" for traveling, but you'll need to be aware of implications for image quality and speed. Nobody but you can decide what to buy, and if you want help you'll need to tell us what's important to you. – Caleb Sep 15 '15 at 19:11

Teleconverters tend to be better when used on f/2.8 or faster lenses and on primes vs. zooms. Adding one to a 70-300 consumer-grade zoom (if you don't have the L version of the 70-300) is problematic at best, since most of these are f/5.6 lenses at the long end, and adding even just a 1.4x tc to it makes it an f/8 lens--at which point an entry-level dSLR probably can't reliably autofocus, or at least will autofocus very slowly. Which kinda sucks for wildlife shooting. A 2x tc would make it an f/11 lens and is right out.

In addition to the lower aperture issue, TCs nearly always add some softness to the image, so if you really want all the detail you can muster, a longer lens is liable to be the key. I would not, however, recommend looking at cheap mirror lenses for this (again, maximum aperture, and autofocus may be issues, and super-cheap ones can be quite soft). Gird your loins and expect a four-figure pricetag.

So, my recommendation would be to go for the longer lens. HOWEVER. 400mm lenses can be comfortably handheld. 500mm lenses, it's a matter of individual experience, strength, and handholding capabilities as to whether or not they can be handheld. And using a lens for the first time on a trip may not be the easiest way to gain said experience. I would highly highly recommend taking a whirl through Roger Cicala's lensrentals video on the Canon supertelephoto lenses, and his other youtube video on support systems for superteles, so you can get a sense of what's involved. This is a very far cry from using a consumer grade 70-300 (or even the 70-300L), in terms of the weight/bulk of the lens.

Personally, I'd recommend renting a 100-400L, or if you really have to go for one of the great whites, budgeting for an extra few days rental of a 500mm or longer lens so you can get used to lugging it about and handling it and possibly a gimbal head.

See also:

  • The newer Sigma and Tamron 150-500mm zooms do surprisingly well. And they are nowhere near as big/heavy as the 400mm and up primes. Although they are at f/6.3 on the long end, they report f/5.6 to the camera so that AF isn't disabled. In good light they AF fairly well, at least on the bodies with dual cross type center focus points. It all depends on just how much one can or is willing to pay for the slight increase in image quality. – Michael C Sep 16 '15 at 2:20
  • @MichaelClark, I didn't say the 150-500 choices are bad. I just meant that for an inexperienced user with a 70-300, the 100-400L as a rental and for travel is probably easier to handle, and higher quality than the Sigma 120-400. The 100-400 is surprisingly compact. And we are talking about balancing this on a dRebel. – inkista Sep 16 '15 at 3:02
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    The new Sigma 150-600 C and new Tamron 150-600 are about the same size/weight as either version of the 100-400, especially when fully extended. And this is where most of those type lenses tend to be used the most. I wasn't referring to the older 120-400 (or 50-500, etc.) the-digital-picture.com/Reviews/… – Michael C Sep 16 '15 at 3:34
  • The image quality of the new Sigma and Tamron offerings are also quite a bit better than those older lenses. – Michael C Sep 16 '15 at 3:39
  • @MichaelClark I'm terribly out of date, then. By newer I thought you meant the OS versions. Thanks! – inkista Sep 16 '15 at 16:23

I also had to make this choice.

For the TC you must be 100% sure that it goes with your lens. The advantage of a TC is that it is cheaper, smaller, and lighter. A 150-500 will be more expensive, bigger, and heavier but a better aperture.

If possible I would recommend rental of a 150-500. This gives you the possibility to test it out for real. If you like it then buy it. It is an investment but if you like to take pictures of wildlife it will be worth the investment.

  • And if you need lens only for one trip, then renting may be preferred option. – kofemann Sep 16 '15 at 20:40

I'm not sure there's even a Canon TC that will work with that lens, which means a lower quality TC. And loss of at least one stop of light. All in all, perhaps not better quality than simply enlarging the critter when editing the photo. Not only that, but auto focus may suffer a bit, so that can degrade image quality as well.

Unfortunately, TC's work best on the better fast prime lenses, and are accordingly expensive.

Even buying a relatively more inexpensive long zoom has similar trade offs. There's just not a good way around the fact that you get what you pay for. Alternatives might be a good older used lens, or maybe even rental.


A teleconverter will magnify the image produced by your lens on the sensor, but will not produce a better resolution than your original lens had. It just cannot: it comes after the lens on the optical path. In other words, if two points were too small/far away to be distinguishable with your lens, the teleconverter will not allow you to distinguish them.

The teleconverter would be interesting the optical resolution of your lens were finer than the one of your sensor. This is usually not the case with modern cameras: a good lens will give you around 10 Mpixels of optical resolution (usually much less for a zoom, look for numbers on DXOmark), and your sensor is much finer.

So, you shouldn't expect from a teleconverter much better than what you get by cropping your images digitally to fake a bigger zoom.

The bad news is that zooms with focal length longer than 300 mm are usually quite expansive. But I guess that's the price to pay if you really want a telephoto ...

  • The DxO Mark lens Mpixel rating is less than a true measure of the resolving power of a lens. If you want to see anything useful at DxO you need to look at the actual measured data, not the "scores" that figure in a lot of other factors that may or may not be applicable to your specific situation. – Michael C Sep 16 '15 at 2:23
  • The score summary is usually at the best focal. If you are to buy a teleconverter, you're probably interested in the longer focal where the lens is indeed much worse. – Matthieu Moy Sep 17 '15 at 7:56
  • The score summaries at DxO Mark often have very little to do with the reality of the actual test data. My point isn't about the lens per say, it is about the methodologies that DxO Mark uses to arrive at composite scores. They very often weight things heavily in favor of factors that are not much of a concern to the average user while minimizing differences that might be much more important to a particular user. – Michael C Sep 17 '15 at 9:58

A converter will decrease your lenses lowest aperture, or make it less useful when it gets darker or shady. Plus, you are limited to a 1.4x converter, as the 2.0 converter will likely cause issues with the autofocus on your lens, since most Canon cameras require f5.6 or better to focus. The 2x converter adds 2 stops. At 300mm, your lens is already at f5.6, so adding one or two stops will cause it to stop autofocusing. I would avoid the converter route.

Therefore, getting a lens is the best option. Don't forget that you can rent a lens as well, which means you can likely rent a much better lens than you likely wish to purchase.

http://www.the-digital-picture.com/Reviews/Canon-Extender-EF-1.4x-II-Tele-Converter-Review.aspx http://www.the-digital-picture.com/Reviews/Canon-Extender-EF-2x-III-Review.aspx

  • Several Canon cameras enable AF with the center point using lens/extender combinations at f/8. How well it works is another discussion, but in bright light it works reasonably well. – Michael C Sep 16 '15 at 2:15
  • True, the 1D series and 5D3 can focus at f8, but the camera mentioned in the question is a 650D, which is limited to f5.6 – cmason Sep 16 '15 at 3:00
  • Yep, and your answer just says "Canon cameras" which strongly implies all Canon cameras, including those higher end models absent a qualifier such as your Canon camera, or Canon xx0D series cameras, or lower tier Canon cameras. – Michael C Sep 16 '15 at 3:24

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