NikonNature
Veteran Member
As a birder/photographer on a budget I am in the same boat as so many others who want the longest reach they can get, without the premium price of ‘Big Glass’. I did a lot of research on lens and teleconverter combinations that would increase my focal length, without decreasing my bank account (too much). For me, the best option was this 1.7x teleconverter in combination with a Nikkor 300mm f/4 lens.
When shopping for a teleconverter, the key concerns are image quality, loss of light (f-stop), and focus speed. I will address each one separately…
Image Quality – For me, there is very little loss of image quality when using this TC versus shooting without it. I would venture to say that other causes - flaws in my technique, or unfavorable light - are much more likely to affect IQ than the glass in this teleconverter. With a reasonable shutter speed I am able to get sharp images of even tough subjects, like birds in flight.
Loss of Light – This is a simple numbers game. Any teleconverter will result in a loss of light. The 1.4x TC costs you 1 stop of light and this 1.7x TC costs 1 ½ stops of light, so in my case my 300mm f/4 lens becomes a 500mm (technically 510mm) f/6.7 - a worthwhile trade off in my book. In my experience, the camera is able to focus with this combination up to f/8.
Focus Speed – There is no use denying that this TC does affect focus speed, as I expect all teleconverters do. Trying to describe how fast or slow it is seems futile, since ‘slow’ and ‘fast’ are so subjective. Instead I will simply say that it is noticeably slower with the TC on, but not so slow that I can’t get the shot. I would also add that good field technique can minimize this issue significantly. For example, if you anticipate a subject or shooting opportunity, you can pre-focus at approximately the same distance. That way the lens only has to make a very slight adjustment, which it can do very quickly. For my use, I have even been able to track and obtain focus on fast moving birds like hawks and swallows. Slower subjects like mammals are a piece of cake.
In summary, I have been using this Teleconverter for several years with no issues. The build quality is very good. Being a Nikon product, it communicates with my camera with no issues. I have not used other brands so I cannot make comparisons. I can only say that I have never regretted purchasing it. It has been a great addition to my bag and is on my camera 80% of the time.
When shopping for a teleconverter, the key concerns are image quality, loss of light (f-stop), and focus speed. I will address each one separately…
Image Quality – For me, there is very little loss of image quality when using this TC versus shooting without it. I would venture to say that other causes - flaws in my technique, or unfavorable light - are much more likely to affect IQ than the glass in this teleconverter. With a reasonable shutter speed I am able to get sharp images of even tough subjects, like birds in flight.
Loss of Light – This is a simple numbers game. Any teleconverter will result in a loss of light. The 1.4x TC costs you 1 stop of light and this 1.7x TC costs 1 ½ stops of light, so in my case my 300mm f/4 lens becomes a 500mm (technically 510mm) f/6.7 - a worthwhile trade off in my book. In my experience, the camera is able to focus with this combination up to f/8.
Focus Speed – There is no use denying that this TC does affect focus speed, as I expect all teleconverters do. Trying to describe how fast or slow it is seems futile, since ‘slow’ and ‘fast’ are so subjective. Instead I will simply say that it is noticeably slower with the TC on, but not so slow that I can’t get the shot. I would also add that good field technique can minimize this issue significantly. For example, if you anticipate a subject or shooting opportunity, you can pre-focus at approximately the same distance. That way the lens only has to make a very slight adjustment, which it can do very quickly. For my use, I have even been able to track and obtain focus on fast moving birds like hawks and swallows. Slower subjects like mammals are a piece of cake.
In summary, I have been using this Teleconverter for several years with no issues. The build quality is very good. Being a Nikon product, it communicates with my camera with no issues. I have not used other brands so I cannot make comparisons. I can only say that I have never regretted purchasing it. It has been a great addition to my bag and is on my camera 80% of the time.
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