Would a tele-extender help?

[joyjoy]

I have been using a Canon EF 70-300mm lens for much of my wildlife photos. If I can get close enough I am able to get some amazing shots. I am wondering if a 1.5x tele-extender would help with images like this one:



Granted, I should have made adjustments to my camera to improve the shot, and I should have been using my monopod, I reacted rather than think it through. But would the tele-extender help at all? A new lens is out of the question for another year because of my wedding and I am just returning to work after being laid off. As always, any guidance and opinions are appreciated.

[SmartWombat]

It'll get the beaver larger in the image, but it will make the under-exposure worse.

[Ron Kruger]

An extender would help make the beaver appear closer and larger, but it would also make such as shot as this poorer quality. My advice would be to figure out how to get physically closer so that you can fill frame at something less than maximum focal length. Wildlife photography is a lot like hunting.

[joyjoy]

If I had bothered to adjust for the under-exposure, would it make a difference? Thank you for the imput.

[A.M.D.A.]

joyjoy -

Yes, if you adjust camera settings to compensate for under-exposure you will get a brighter end result. But the fact with tele converters is that they are huge "light absorbers". A 1.5X TC draws about 1/2 stop of light. That means a slower shutter-speed that what you would otherwise get without it.

The Canon 70-300mm F4-5.6 will become something like a 105-450mm F5.6-8.0. This will give a very dim viewfinder, I know from personal experience. For night/evening/dawn shots, the VF will seem almost pitch-black. I would suggest that if you want to use a 1.5X TC, start with a base lens sporting a maximum aperture no smaller than F4, F2.8+ would be ideal. That would give you a converted lens of approximately F5.6 and F4.0, respectively.

TC's are known for increasing chromatic aberrations and reducing overall image sharpness, shoot with a prime (fixed-focal-length) lens in order to maximize image quality. Here is a sample photo for illustrating aberration effects, note the ugly colored fringes everywhere.

Attachment 63651

Camera Brand: PENTAX Corporation 
Camera Model: PENTAX *ist D      
Lens model: SMC PENTAX-A* F4 300mm lens.
TC model: 2X Pz-AF BBAR MC7 TAMRON-F AF Tele-Converter.
Exposure Time: 1/400 sec.
F-number (equivalent, converted): F8.0
ISO Speed Rating: 1600
Flash Fired: Flash did not fire, compulsory flash mode.
Metering Mode: Center-Weighted Average
Exposure Program: Aperture priority
Focal Length (35mm equivalent, and converted): 900 mm
Contrast: Normal
Saturation: Normal
Sharpness: Normal

jgredline posted an excellent thread here, dealing about TC's and even with several sample images. And I agree with what Ron said, it is usually best to learn how to get closer to your subjects.

[Loupey]

joyjoy, couple of points I'd like to make:

1) Lenses of the 70-300mm variety are typically not sharp enough to allow TC's to be used with much success. Teleconverters multiply everything (including flaws) so one needs to start out with the best lens possible (usually a prime lens).

2) The best teleconverter should be used. For Canon, I recommend the Canon TC's - but Canon TC's won't fit the 70-300mm

3) With the 70-300mm, you may have better success pulling out a cropped image rather than trying to use a TC.


But don't get the impression that TC's are bad. There are times and places when they can be very useful. I use them quite frequently and often the results can't be identified as a TC shot when printed to average sizes (8x12 and 11x17).

[joyjoy]

Thanks for the info. If I could get closer to my subjects I would, unfortunately most of my favorite places to shoot are extremely protected, so getting up close and personal is out of the question unless I want to go to jail or get banned.

Maybe I will just tough it out for the next year, and get a better lens next year sometime.