Sigma 120-300 f2.8 OS or Sigma 300mm f2.8 with 1.4 and 2.0 TC

birder_herper wrote in post #13924186
What body are you using?

I'd agree that the 1.4x would likely be more useful, with better image quality. Getting the 2x as well would be nice when you need the 421-600mm range.

I'd also look for used Sigma 500 f/4.5 lenses. I picked one up a few years back for a price I still can't believe it was offered for! Should also be found around the same price point as a Sigma 120-300 2.8.

I am using a Canon 450D. I am looking at the 7D, but I can't afford both the 7D and the 120-300 OS. I cannot afford both teleconverters at the same time either. So if I have to choose one, you would pick the 1.4?

I am using a Sigma 400mm f5.6 APO Tele Macro HSM at the moment with my 450D and I am missing some reach. That's why I was tipping over to the 2.0 converter. But I guess I can still crop after the 1.4 converter and still get good quality images?

I think if you are missing reach now then I'd go for the 2*TC otherwise you're just swapping one lens for another (and 400 to 420mm isn't much of a difference). I'd also say go for the lens first over the body - the 7D is great, but the 450D is still a very capable camera and with a good lens like the 120-300mm capable of some great shots.

Overread wrote in post #13924214
I think if you are missing reach now then I'd go for the 2*TC otherwise you're just swapping one lens for another (and 400 to 420mm isn't much of a difference). I'd also say go for the lens first over the body - the 7D is great, but the 450D is still a very capable camera and with a good lens like the 120-300mm capable of some great shots.

I am not missing reach all the time, but more like 60% of the time. I will be getting both teleconverters anyways, but I don't know which one to get first... How is the cropped 1.4 in comparison with the 2.0? Is it a big difference?

freddyronny wrote in post #13924283
I am not missing reach all the time, but more like 60% of the time. I will be getting both teleconverters anyways, but I don't know which one to get first... How is the cropped 1.4 in comparison with the 2.0? Is it a big difference?

The cropped 1.4x is visibly sharper, no surprise there. PLUS with the 1.4x your aperture starts at f/4 which is a stop faster than the 5.6 you get with the 2x.
I have a cheap Kenko 1.4x TC which can be had for around $130-150 (Kenko Pro 300 DG).

gabebalazs wrote in post #13924352
The cropped 1.4x is visibly sharper, no surprise there. PLUS with the 1.4x your aperture starts at f/4 which is a stop faster than the 5.6 you get with the 2x.
I have a cheap Kenko 1.4x TC which can be had for around $130-150 (Kenko Pro 300 DG).

Ok, than I'll be getting the 1.4 converter first. I was personally thinking about the Sigma 1.4 converter. Isn't it better than the Kenko?
I want the best possible converter without having to pay a huge amount of money (in comparison with the other converters) without a very big improvement in IQ. So the Canon 1.4 III is not an option, all the others should be possible.

The Kenko Pro 1.4x DG (or DGX) is highly regarded as one of the best 1.4x TCs. I've seen a couple comparison tests and the Sigma was no better.

Should you decide on a 2x TC, I will likely sell mine (almost new, mint Sigma APO EX DG) in the near future since I also have a Canon 2x III.

gabebalazs wrote in post #13924876
Should you decide on a 2x TC, I will likely sell mine (almost new, mint Sigma APO EX DG) in the near future since I also have a Canon 2x III.

Well I would certainly be interested, but I live in Belgium. I assume you live in the USA? It would cost too much in shipping I think. There are plenty of Sigma 2.0 converters available on the second hand market in Belgium anyway