Teleconverter for Sigma 150-500 and 7D

turkeyneck · #1 (**permalink**) 05-10-2010, 07:51 PM

I was wondering if anyone has (or uses) a teleconverter on Canon 7D with a Sigma 150-500mm or the 50-500mm? I have the 150-500mm and was wondering if it is worth getting a 1.4 TC to go with my set up, just to give me that little extra oomph out of the hide on those 'just too far away' shots. I know it would degrade the image but sometimes a poor shot is better than no shot.

Also, have I read or heard somewhere that there is an issue with the sort (make) of teleconverter that is compatible with the Sigma lens? Obviously will need AF to work so am I correct in assuming it has to be a certain make of TC?

Any thoughts/help greatly recieved

johnf3f · #2 (**permalink**) 05-10-2010, 10:44 PM

Tried my Canon 1.4 & 2x converters against Sigmas and preferred the Canons, though this was on a Canon lens. Try both - then decide, but before you do check for rear element clearance. I think yours is OK but check first.
Although I have bought the both the Canon converters I find their performance rather variable - especially on zoom lenses. They were poor to v poor on my 100-400 but are excellent on my 70-200 f2.8! Not too hot on my 300 or 600 but very good on my 100 Macro (with modified extension tube)!?!
The moral is go try them and see what you get! Also remember they will degrade your autofocus speed, possibly not allow af at all, so try before you buy!
If you want to try mine out let me know and we can arrange a meet.

squishy · #3 (**permalink**) 06-10-2010, 08:12 AM

I think it's tamron's TC that doesn't report the aperture, so you'd keep autofocus.

But it'll be very slow.

The 150-500 would become an f/9 at the 500 end, and you'd still have to close it down to get good results.

StuMack · #4 (**permalink**) 06-10-2010, 05:06 PM

Hi all

I've just ordered a sigma 1.4 for my 150-500 as a number of reviews say the lens will still autofocus, however I have agreed with the camera store to take it back if it doesn't!

Stu

Geoff F · #5 (**permalink**) 06-10-2010, 06:44 PM

I have used a Canon 1.4x on a Sigma 150-500 but I had to use a 12 mm extension tube as a spacer which means that the maximum focusing distance is reduced (focusing at infinity is lost). And only manual focus.

Although it worked, I wasn't keen on the results and found that cropping and resizing produced sharper results.

glsammy · #6 (**permalink**) 06-10-2010, 07:48 PM

Some TC's won't work with Sigma lenses due to the shape of the rear lens. This is true of the Canon 1.4. The Kenko Pro 300 1.4 will fit, although you can't retract the lens right back to 50mm without fouling the TC.
There's also the point that it's hardly worth the effort. If the light is perfect they can work quite well, but in anything less than that the quality drop off, plus the loss of the extra stop make them hard to recommend.
I found that I could crop a normal image and retain better detail against a shot taken using a 1.4X TC.

turkeyneck · #7 (**permalink**) 06-10-2010, 08:34 PM

Thanks to everyone who has posted on here, loads to mull over now.
You know what made me think about all this was...... there's this darn kingfisher that every time I photograph it and then crop, it's just slightly too grainy (too small in the frame), the options are--
1. get a larger lens
2. get a TC for my lens
3. get out the hide and move the perch a couple of yards closer
4. only photograph 2' tall kingfishers or
5. don't photograph kingfishers, loads on here to go around any way

Once again thanks for everyones help

johnf3f · #8 (**permalink**) 06-10-2010, 09:24 PM

Quote:

Originally Posted by turkeyneck

Thanks to everyone who has posted on here, loads to mull over now.
You know what made me think about all this was...... there's this darn kingfisher that every time I photograph it and then crop, it's just slightly too grainy (too small in the frame), the options are--
1. get a larger lens
2. get a TC for my lens
3. get out the hide and move the perch a couple of yards closer
4. only photograph 2' tall kingfishers or
5. don't photograph kingfishers, loads on here to go around any way

Once again thanks for everyones help

I recommend Herons!
You saw what happened when I went for a longer lens!
WARNING long lenses will damage your wealth! (and health if you are married!).
Get close is the best - though not the easiest.
P.S. PM me if you are going down the wetlands and I'll bring my t/c's so you can play.

agooday · #9 (**permalink**) 19-10-2010, 03:47 PM

I used a Sigma 1.4 Teleconverter with my Sigma150-500 on a 50D. Minimum (or do I mean maximum?) aperture was 9 and autofocus didn't work (a function of minimum aperture). It was always very close as to whether the TC was better than a crop no TC, which is to be expected for a non prime I guess. I'm now using the Sigma 1.4 TC with a canon 400 f5.6 L. Again, not obvious that it's much better than cropping, but still getting to know the lens. Hope that helps.

turkeyneck · #10 (**permalink**) 19-10-2010, 09:06 PM

Yeh thanks agooday, it does help. I've tried a couple of TC's and none of them worked with my Sigma, I was expecting this really.

I might just shelve the idea and put the money towards the Canon EF 500mm f4.0L USM IS Lens, (once I've won this Wednesdays lottery)

I think really I'm trying to get a better image without the grain/pixelation I'm getting when cropping. From what I can gather and have been told, a primes gonna knock spots of my Sigma 150-500.

Hmm.....prime or marriage?