Sigma x2 v Canon X2? Help Please

Hi Guys and Gals, can I ask a question that has probably been asked before but one that I have been unable to fathom out the answer to. I have done a few ‘searches’, so perhaps I’m using the wrong ‘key’ words.

Anyhoo, until recently I was going to buy the 100-400mm Canon, but a Trek Madone (Road Racing bicycle) at massive discount came my way and now I can’t afford one. My question (see I got to it eventually) is if I buy a x2 converter for my Sigma 70-200mm lens, would I be better off going for the Sigma version or the Canon version? and do I lose AF with both converters? I’m happy to pay the extra for the Canon version if it gives better IQ. Or if the IQ of both is only average, then would I be better saving up for a Bigma or even waiting till I can afford the 100-400mm Canon again (assuming the potential new long Canon zoom hasn’t come out by then) I have a Canon 350D Body. I realise the Canon IS is a real boon, but I can just about live without it I think and this x2 measure is only meant as a stop gap one.

I already have a Jessops x2 converter and it is horrible, it make the images look like I’ve applied a magnifying glass to the image and rubbed butter on my eyeballs. Oh and one other question about X 2s, if I was to put it on my 17-55mm lens would it be any use as a long portrait lens or would I lose too many stops to be make it worthwhile.

Sorry for all the questions but I’m a technical incompetent.:o



On further investigation, I see that the Canon is ot compatible with the Sigma lens, so perhaps my question is a waste of time. so I will re-examine the posts on the Sigma lens with just the Sigma x2. Thanks. Oh and if anyone does know if a Sigma x2 would fit on the 17-55 f2.8 and whether it would be worth doing so I’d still be grateful. Many thanks Amanda.

Alot of people use teh Kenko tubes. These seem to be very good indeed.

Is the Jessops one that bad! I'm currently thinking about buying it, but now you have made me think,could you either PM me some pictures or just put some in this thread that were taken with the jessops 2x converter.

thanks, sorry to kinda hyjack the thread

I think that the only TCs that would fit on the 17-55 are the Tamron or Kenko ones. TCs are generally better suited to tele lenses, however.

I believe the Jessops 2x is a re-badged Kenko (non-Pro). The Sigma, Canon or Kenko Pro converters would be better, but if you're that unhappy with the Jessops one then I doubt you'll be happy with any of the 2x TCs. They all degrade image quality and focussing to a very significant degree.

thanks for that gcogger

So least the jessops ones good, they should be a good extra for my 90-300 canon lens

My x2 images are currently on my Desktop which is at the menders. So I haven’t got access to them at present (I didn’t bother to back the x2 files up, they really are soft.) I have seen some pictures on here with the 1.4 Canon TC and Canon lenses and the pictures looked great I thought. Perhaps it’s just me and my incompetence, but the Jessop X2 has hardly any elements in it so I guess it would be a miracle if it could do its job with out adding several distortions

willy b wrote in post #2890822
thanks for that gcogger

So least the jessops ones good, they should be a good extra for my 90-300 canon lens

I really wouldn't use a 2x converter (and probably not even a 1.4x) on a canon 90-300 lens. Teleconverters need a very good lens to be worthwhile.

For example, I've recently tried the Kenko Pro 2x converter with a Sigma 100-300 f/4 EX (one of the very best zoom lenses around) and a Canon 300mm f/4 L prime (an absolutely stunning quality lens), using the 'tape trick' to allow auto focus. On the Canon prime, focussing was very hesitant but just about usable, and the quality was just OK. On the Sigma zoom, focussing was hopeless even in bright sunlight and simply not usable. The quality was pretty awful too, and I wouldn't use it even if I could get it to focus.

I don't have the link now, but I once read a very noteworthy comparison that compared cheap and brand 1.4x and 2x converters.

Most notable to me was that all of the cheap 1.4x converters gave significantly better images than the 2x Canon converter on a 70-200/2.8 lens.

I would not just blame it on the Jessops converter being lower quality (I'd assume they are re-badged cheaper Tamron or Tokina converters), but also on the fact that a 2x converter has more visible quality loss than an 1.4x converter.

My suggestion ... go to a good photo shop and try it out with your lens.

Best regards,
Andy

If you use a Sigma TC on a Sigma 70-200, you don't lose AF. It looks like a good combo, if the IQ doesn't degrade much. A 140-400 f/5.6 AF lens for just $200 more? Nice...

Here's the compatibility list. http://www.sigmaphoto.​com/lenses/lenses_tele​.asp#canon

Only the Tamron and Kenko will fit that 17-555mm.. but even then it's totally not worth it.

You have the 70-200mm to get you past the 17-55mm, so use it instead.

Now you don't have anything past 200mm, and this is where t-cons come into play.
As mentioned, you may want to consider a 1.4x first. It's image quality is far better.

On the Sigma 70-200mm, you should get either a Sigma 1.4x (will only fit certain lenses, the 70-200mm included) or a Kenko Pro or the better Tamron.

Thanks guys, I’ll have another look round this site for examples with these combos. Appreciate the advice and it certainly looks the way forward to use a TC for relatively little outlay in order to give me a longer lens.