Sigma Teleconverters have the ability to turns your lens into an optically longer lens. For example, my Sigma 120~300mm f/2.8 with a 1.4 TC is a 170~420mm f/4.0 or when coupled with a 2.0 TC the lens will equal a 240 ~ 600 f/5.6 respectively. After using both for about a month the results speak for themselves; On this website are some photos taken with both 1.4 and 2.0
Teleconverters, just browse through the photos, the comments will indicate the use of which Teleconverter and my settings for the camera. here mainly are the results; http://www.truetoad.com/Gallery/Wildlife/Birds.aspx.
My hands-on experience using the Sigma 1.4x EX APO DG: Lets start with the 1.4, using this teleconverter had very little impact on focus performance or image quality, in fact – I can almost swear it improves my image sharpness when used it with my 120~300 2.8 sports lens, I was VERY Pleased, this Sigma 1.4 teleconverter on my faster f/2.8 lens it worked perfectly. The sharpness, contrast, and focus speed was maintained to a performance level that never caused me any concern, and I found myself just leaving the TC attached for long periods of time. In short, I highly recommend the Sigma 1.4x EX APO DG for any of the Sigma lenses that will accept it - check the compatibility on the Sigma Site, link below.
My hands-on experience using the Sigma 2.0x EX APO DG: While walking through a wildlife refuge on a nice clear day, I mounted the Sigma 2.0x onto my Sigma 120~300mm. This combination worked very well on this bright day overall, the focus was noticeability slower and depending on the subject I did experience some focus hunting at times. However, knowing this and getting accustomed to this combination, I modified my shooting habits, and things improved. As an example, if the animal is in front of a cluttered background and blends in - the lens with the 2.0 tc may have difficulty with focus. to help overcome that issue, I use the limiter and simply manually focus then hit the focus button letting the lens do the rest. In situations where the animal/bird has a clear background, the combination works very well.
I used the focus limiter settings for far or near depending on the situation – this did improve the overall focus performance, but one could tell the focus was somewhat slower, but with the added reach – I could live with it. The overall sharpness and contrast of images I captured with this combination were very pleasing, in fact, I was able to easily capture many nice birds in flight, here is one shot (Click Here), and a Gull walking, and Canada Geese on water.
Overall thoughts 1.4x TC: I can without hesitation recommend the Sigma 1.4x EX APO DG teleconverter to be used on any of the Sigma compatible lenses
. Please check compatibility before your purchase – Sigma Teleconverter Compatibility link is below., Nikon and Canon bodies seem to be a good match.
Sigma_20x Overall thoughts 2.0x TC: If you shoot mainly on bright sunny days this is a solid investment, the price is very reasonable and quality just as good as the competition as compared to Nikon or Canon 2.0X TC, coming in at almost half their cost, but I am hesitant to do a full recommendation due to the slower focus results I experienced in low lighted situations, in some situations my camera lens combination spent a lot of time hunting for the focus, birds in the trees for example. However, if you don’t mind working your technique, and your situation allows for manual focus, the resulting images will be rewarding.
Keep in mind: All 2.0 Teleconverters no matter who makes them reduce light and f-stop by 2x e.g., f/2.8 will be a f/5.6, and a f/4 will be a f/8. As it stands today, f8 is about the limit for even flagship cameras when it comes to focus. A fact of photographic life.
Images taken with the Sigma Teleconverter 2.0 are very pleasing while maintaining sharpness overall. Sharpness is also relevant to the overall capabilities of your lens without the converter, if your lens is not sharp without the TC, then you can bet it will be worse with it. With the 2.0x mounted on a 300mm for example, you are out there in optical length and that requires higher shutter speed, and a steady platform (tripod) to make the best of the situation. So, the fault may not be in the design of any TC but the technique of the user.
I have actually shot with a Nikon 500mm and got horrible results while a friend of mine using the same lens had perfect results, this was due to my lack of experience in using longer lens a few years ago. So, when you mount a 2x you need to think more about how you shoot to achieve the best results in sharpness in terms of the ISO, f-stop, and shutter speed. That said, not much can be done to fix slow focus except provide more light and contrast, and in the case of the Sigma 2.0x TC, more light is what you need to maintain faster more reliable focus. I find myself using the TC on bright sunny days that afford the best opportunity for its use or when I am setup waiting and have my focus already fixed. On less favorable days I either shot without the TC or use the 1.4.
My Hints for best use of Teleconverters:
- If you don’t need it “take it off” and or consider using a crop sensor camera body if you have one.
- Try to keep the shutter speed up @ least equal to the focal length of the lens + converter, @ 500mm = 1/500second, higher shutter speeds are even better.
- Use Optical Stabilization when off the tripod.
- When panning birds in flight – Pan as steady as possible, maintain a high shutter speed.
- For best results mount your lens on a gimbal/tripod while panning
- Practice. Practice, Practice; Get used to the lens teleconverter combination through practice with and without the OS on, also don’t forget if your shooting handheld, your shooting technique is important to maximize steadiness with higher shutter = sharpness.
- If possible, seek bright sunny days which provides you with wonderful lower ISOs along with higher shutter speeds. The weatherman may not always accommodate, so be prepared to drag a tripod/monopod along just in case.
- One last thing - LONG lens amplify atmospheric conditions (heat waves) when shooting across open areas. Even the best shooters using the best glass will be victims of atmospheric conditions
Help the site buy a Sigma 1.4 Teleconverter: Buy a Sigma 1.4 Teleconverter
Help the site buy a Sigma 2.0 Teleconverter: Buy a Sigma 2.0 Teleconverter
In my honest opinion, Every Wildlife Photographer using a longer lens should have at least one Teleconverter in their bag, and I recommend if you are starting out pick up the TC 1.4 unless you have a very specific reason for the 2x focal length factor.
Thanks for reading along - See you on the trail.