+ and - to 1.4x teleconverters

Location : South Oxfordshire Spotter Watch Member : No

Hi there,

I have been looking at getting a 1.4x teleconverter for my Sony Alpha, just wondering what your experiences of teleconverters have been, both positive and negative.

It will have a Sigma 70 - 300mm lens on it for most of the time.

Looking forward to your replies

Moderator Location : In a layby

I use a 1.4x teleconverter on my Canon 70-200mm f4 lens, making it a 280mm. There is no image quality loss at all. Silly question, as I dont know much about the Sony Alpha's but can you use a teleconverter with the sigma 70-300? you cant on a Canon Confused

Location : South Oxfordshire Spotter Watch Member : No

Thats good to know there is no quality loss.

There is one at warehouse express that will work.

Admin Location : Bristol, UK

Mattyjc wrote:: Thats good to know there is no quality loss.

I'd be very surprised if there wasn't any quality loss or decrese in focus speed with a Sigma 70-300 lens and 1.4x tele. The tele's normally only work (Quality and Focus wise) on the very expensive lenses - Such as primes and high end zooms.

I'd go into a store with your camera body and lens and ask to try before you buy. Test the Focus speed and take a few picutres and see what you think. It may be acceptable, but i'm sure you would notice a difference.

Mike

Subject: Re: + and - to 1.4x teleconverters 2009-07-24, 16:31

Mattyjc wrote:: Thats good to know there is no quality loss.

There is one at warehouse express that will work.

will it physically fit though? there is a good change that the teleconverter may come into contact with the rear element on the lens damaging both bits of glass

Location : Glasgow

Sigma don't list their TCs as compatible with their 70-300mm http://www.sigma-photo.co.jp/english/support/faq/condaitr.htm but that doesn't mean that e.g. a Kenko won't fit.
Assuming that you can find a tc that is physically compatible the main problem is that you'll lose a stop & very possibly therefore AF once the lens has dropped to f5.6.
However, as Sony use sensors that in theory are good down to f7.1 you might get away with it but expect AF to be slow.

Location : St Ives, Cambs

Mattyjc wrote:: Hi there,

I have been looking at getting a 1.4x teleconverter for my Sony Alpha, just wondering what your experiences of teleconverters have been, both positive and negative.

It will have a Sigma 70 - 300mm lens on it for most of the time.

Looking forward to your replies

I have a Sony 70-300mm bog standard lens and a Sony 70-300mm SSM G lens for my Sony Alpha 350. I have tried both with a Kenko 1.4x converter and AF will work if the subject matter is static but moving, as in flying shots, 90% of the images come out 'soft' or slightly out of focus. Can be used on manual focus though.

Brian

Location : South Oxfordshire Spotter Watch Member : No

Many thanks for your replies,

think I'm going to re-think this!