Zooming in

[Martin Brazil]

Photographing birds and wildlife is really my thing but I am starting to find that my AF-S Nikkor 70-300mm is a bit limited for some of the more nervous subjects and I'm thinking that I need some more zoom power. The more I look at my options the more confused I become so I have some questions.
Money being an issue I have been looking at these three lenses,
Sigma 50-500mm f/4-6.3
Sigma 150-500mm f/5-6.3
Sigma 170 -500mm f/5-6.3
I'll say from the start that the 170mm is about 2/3 of the price of the other two which gives it a plus point.
The 150 and 50 are about the same price though so why would I not buy the 50 and have the extra flexibility of being able to zoom out further ? Is there another consideration that I am missing ?
From the write ups Sigma seem to be highly recommended, does anyone have any experience with these lenses ?
I see that many people use teleconverters, 1.4, 1.7 and 2x. How do these stack up against lenses, how does a 300mm with a 1.7x compare to a 500mm lens ?
Why bother with a 1.4 and 1.7 when you can use a 2x and not zoom out so far ?
I saw a 300mm macro 1:2, would this bring the image 2x closer thus acting like a 600mm ?
Any alternative suggestions or further thoughts on the subject greatly appreciated.

[Loupey]

Sorry, I know nothing of the three Sigma lenses you mentioned so I can't help you with your main questions.

I see that many people use teleconverters, 1.4, 1.7 and 2x. How do these stack up against lenses, how does a 300mm with a 1.7x compare to a 500mm lens ?
Why bother with a 1.4 and 1.7 when you can use a 2x and not zoom out so far ?

You may want to consider going with a fast, high quality prime (like a 200mm, 300mm or even a 400mm) and then coupling a HIGH QUALITY teleconverter to it to give you the occasional reach you need. You may actually get better image quality out of this combination than trying to get an all-encompassing zoom.

I saw a 300mm macro 1:2, would this bring the image 2x closer thus acting like a 600mm ?

The 1:2 designation means that the lens can give 1/2 life-size macro images. It has nothing to do with 2x nor teleconverting abilities.

[brmill26]

You're right, Loupey, but a fast prime with sufficient length is going to be way out of reach since he stated budget is a concern.

I don't have any personal experience with those lenses either, but I know the "Bigma" 50-500 has a pretty good reputation. Having seen the images from it though, and as slow as it is at the long end, even if you could mount one I would say you should never use a TC of any power with that lens.

Google is your friend... search for info about those different lenses, I'm sure you'll find someone who has either tested them or who has written about them.

[Martin Brazil]

Thanks Loupey, Brad, much appreciated, but I am more interested in general theory of zoom lenses than the particular lenses.
I have already done as you suggest Brad and googled all three lenses and I am sufficiently convinced that they are up to the job. I was not so much thinking of mounting the 500mm on a TC, more about whether to buy the 500mm or a 2x TC for my 300mm. From what I can make out the major draw back with the TC is that you loose 2 f stops which would bring my 300mm down to f8 thus slowing down the speed which is possibly going to be an issue as I mostly shoot birds.
You mentioned High Quality Loupey and this is the main reason I am still thinking of the TC rather than the lens. My 300mm is a Nikon and I can get a Nikon TC to go with it, maybe not a total pro set up but certainly higher quality than the sigma.

Loupey, I did not think the macro was like a zoom but I'm still confused as surely something that is magnified twice life size looks like it is twice as near, no ? Actually I think this is a subject for another thread.

Thanks again guys.

Martin

[Loupey]

Martin,

1) The macro is read "half life-size" and not "twice life-size". Very few dedicated macro lenses, without external help (bellows, extension tubes) can go beyond "life-size".

2) My earlier reference regarding using teleconverters was with fast (not ultra-fast) primes like a 200mm f/2.8 or a 300mm f/4. I was NOT endorsing the use of teleconverters with 70-300mm zooms. At the risk of sounding blunt, 70-300mm lenses (by any manufacturer) tend to be "consumer grade" in that the image quality is somewhat compromised by the need to make a highly portable and affordable lens. Remember that a teleconverter multiplies EVERYTHING - the good and the bad. At best, an "A" teleconverter matched to a "B" lens will result in "C" images.

[mjs1973]

I have been using the 170-500mm lens as my main bird/wildlife lens for several years now. It's an OK lens, but it does have it's limitations. To start with, you are going to want a good solid tripod under this lens, or any lens in the 500mm range. The max f/6.3 aperture is painfully slow, as is the auto focus. The AF is also noisy. I think this lens has been updated since I got mine, but I don't know just what it is that they updated on it.

The lens is pretty soft at f/6.3 so I try to shoot mine at f/9. I will shoot at f/8 if I need a little more speed. Unless you have a body with great high ISO performance, you are going to have some really slow shutter speeds, unless you're shooting on a bright sunny day. Most of my shooting is done in the mornings and afternoons when light is pretty limited and this is when the slow apertures are really noticed.

I do like the zoom range, and sharp photos can be had with the right technique. A sturdy tripod, and a cable release are almost mandatory with this lens.

So, would I recommend this lens? Maybe. Depends on what your expectations are, and your budget. I have taken some photos that I'm very happy with using this lens, but I have also missed many opportunities do to it's limitations. There are much better lenses on the market, but they may be out of your budget.

Loupey's suggestion of a good prime, like a 300mm f/4 with a TC is solid advice, if it's in your budget.

[Sushigaijin]

"half life size"

Is the maximum magnification based on close-focus, and refers to the size of the image on the sensor. So this might only be about three feet from the camera, depending on the lens. What 1/2 macro magnification tells you is that the lens can focus closer than a non-macro type lens. So a regular lens might only be capable of filling a frame with a sparrow, but a 1/2 macro is more than capable of filling the frame with just the sparrow's head. BUT, this isn't at the same focus distance - all other things equal, you will have to be MUCH closer with the sparrow's head shot.

And general zoom theory says that typically the wider the zoom range, the less image quality. It's not always true, but it's a good thing to keep in mind. I know the sigma 50-500 and the sigma 150-500 are both popular birding lenses. Both of these will be higher quality than a nikon 70-300 with 2x teleconverter.

Another thing to keep in mind about teleconverters is that they degrade the image more as they magnify more - so a 1.4x will usually give much greater picture quality than a 2x.

[Loupey]

I can't say how valuable the 300mm f/4 + 2x TC combo has been for me. I have loads and loads of examples and I still use it when I have neither the space nor the opportunity to use my 500mm.

But I bought my 300mm specifically because it has IS (internal stabilization) and I knew I'd be using it with a TC and extension tubes (not at the same time). I don't know if Nikon's version has the equivalent VR. Otherwise, as mjs1973 mentioned, you will absolutely need to use a very stable platform when TC'ed out to 600mm. On my 300mm + 2x combo, I shoot hand-held all the time - the IS makes that big of a difference.


As for zooms, my experience when shooting wildlife is that the zoom is going to jacked to the long end most of the time anyway. So why buy a zoom for wildlife? Of course in my area, "wildlife" tends to be very small and very wary so take that for whatever it's worth.

[mjs1973]

As for zooms, my experience when shooting wildlife is that the zoom is going to jacked to the long end most of the time anyway. So why buy a zoom for wildlife? Of course in my area, "wildlife" tends to be very small and very wary so take that for whatever it's worth.

I couldn't agree more Loupey. Especially if you're shooting birds. Even when I set my blind up in the back yard by the bird feeders, I'm still taking most of my shots at 500mm and that is at a distance of about 10'. Of course there are going to be times when that is too much, but the vast majority of the time, I'm zoomed all the way out.

[Loupey]

Yeah, even with long lenses many people are surprised just how close one must still be to get a good, detailed shot.

When I'm in the company of birders, they assume that, because my lens is phyically larger than their spotting scopes, I can shoot what they're seeing out at 100'+. But for small birds (sparrow size), my ideal range for a 500mm/600mm lens is about 20' For medium duck-sized birds, the range may be 30'~40'.

So I guess what I'm trying to say is that simply buying a longer lens may not solve the problem. Learning good stalking and shooting techniques will be equally, if not more, valuable.

[Martin Brazil]

First off thanks everyone for taking the time to answer my naive and at times plain stupid questions. I really appreciate the assistance.

The macro is read "half life-size" and not "twice life-size".

Of course it is Loupey, dumb of me, realising that it all makes a lot more sense. Thanks for the macro theory explanation too Erik, very useful.

Well, reading all the posts what to do ???

Mike, thanks for the feedback on the Sigma 170-500mm. I believe one of the things they upgraded was indeed the motor, the lenses now have HSMs (high speed motor) so I presume when changing the motor they fixed the problem of noise too.

I have been looking at all the medium reach lenses, 300-500mm, and also the TCs and the problem I keep seeing is that unless I spend ridiculous amounts of money the f stop is up at f 8 and above, which I feel is going to be a serious limitation in many situations.

Loupey, I looked into your suggestion too of an f4 300mm and a 2x TC and I was pleasantly surprised to find Nikon do this lens for about $1,300 but it does not have the VR so is going to need a tripod for sure. Bearing in mind most of my photography expeditions involve wading about in swamps and pushing through thick jungle attaching a tripod to the camera is not really feasible. Add $500 more for the TC and its sliding up out of my budget too.

All this brings me round to Loupey's final post

I guess what I'm trying to say is that simply buying a longer lens may not solve the problem. Learning good stalking and shooting techniques will be equally, if not more, valuable.

Probably the best piece of advice I have been given in a long time. I think for the time being at least I'm going to stick with what I have and concentrate on improving my techniques rather than quite possibly wasting a whole load of money on unsuitable kit. Maybe when I am a world renowned wildlife photographer I'll do $10,000 on a 400mm f 2.8 but until then my 70-300mm will have to do.

Thanks again guys.

Martin

[freygr]

Martin, with Telephoto Converter specially with the 2X the lens becomes SLOW. At 500mm F8 lens with a 2x telephoto converter makes the lens an F11. My 300mm F5.1 is over 2 inches in diameter! Just remember the slower the lens is the slower the AF is.

[Martin Brazil]

Thanks for the advice GRF, I have really given up the idea of using a 2xTC with my current lens (nikkor 70-300mm) although last night I was thinking I might pick up a 1.4x as its not too much money and should give me a little more reach without sacrificing too much in the way of speed or picture quality.