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07-11-2017, 07:14 AM   #1
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a dumass newbie question -- pretty basic

Sorry, folks, this is pretty fundamental, but I dont get it. I dont understand how those super expensive wild life lenses can be of fixed mm size. Lets say you are hiding in the bushes trying to take a picture of your subject far away -- you aim with your 500mm lens --- and either that bird is too giant because you are too close, or too small because you are too far away. Am i right? So shouldnt all that stuff have a mm zoom "range" to it? I have one prime 50mm lens -- and I do a lot of walking to and from my subject. I dont mind because this is under "normal" city/suburbs environment. How does this work when you are standing on the shores of the river?
Sorry, I know this is a stupid question.

07-11-2017, 07:23 AM   #2
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If you're too close, yes you're basically stuffed. (Some might argue you could stitch together a number of shots?!)
If it's too far away you have to crop to increase the image size.
07-11-2017, 07:45 AM   #3
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Part of the reason goes back many years... zoom lenses weren't very good. Research in zoom lenses were far behind prime lenses. So for the best shots, you would use the best prime, and hope the fl was appropriate. While the quality of zooms have increased immensely over the years, prime lenses tend to be faster, and optically better because they only have to correct one focal length instead of the entire range, which will always have a give and take.

Hope this helps a bit.
07-11-2017, 07:50 AM   #4
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And for drastic situations, there are teleconverters.

07-11-2017, 08:01 AM   #5
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If you're close up, then you would need to switch lenses. If you're too far away, the prime is usually as long or longer than the zoom's maximum fl anyway.
07-11-2017, 08:07 AM   #6
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There are quality zooms now, they tend to be VERY large and pretty expensive. It's a lot for an amateur to justify.

This is also the reason you see photographers with multiple cameras slung from slings, or mounted on a tripod crossbar. Bad range for camera #1, switch to #2 or #3. I've done this in the field, but need to buy a sling setup built for 2 cameras, it was very awkward otherwise. Taking my longer zoom along with my 100mm macro let me get a few shots, though I still really want a nice long telephoto prime.

Don't be ashamed to ask questions. We're all here to learn and distribute experience.
07-11-2017, 08:20 AM   #7
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most zooms that go beyond 500mm haven' t been premium lenses - an honorable exception, of course, was the Pentax 250-600mm in its various iterations, which was a * lens - and a great performer from what I've seen
07-11-2017, 08:28 AM   #8
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And for some subjects, think hummingbirds, it's seems virtually impossible to get too close, even with a "long" lens.

07-11-2017, 08:33 AM - 2 Likes   #9
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Grab a 500mm lens and go to any wildlife reserve. Sit in the hide (or bushes) and point it at the pond or feature that the hide has been created to capture a view of. Unless it is a Pterodactyl you are trying to capture, your lens won't be too long, and yes you will have to crop the image.
07-11-2017, 08:50 AM   #10
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This is purely a matter of using the right tool for the right job.There are plenty of places a 500mm prime lens is the right tool, there are equally a number of places where it is not.Sometimes you need a hammer,sometimes you need a screw driver.It sounds like you'd best be served by a super zoom.I often use the Sigma 50-500 which is superb.Newbie's like yourself often get fooled because a number of "average" 500mm are available cheaply compared to the more quality long zooms but unless you're into the types of shots that they excel at it becomes a paper weight on the shelf that you seldom take out.No lens works for everyshot but for photographers like wildlife specialists or sports shooters they might not be able to do the job without the big expensive 500mm.
07-11-2017, 08:56 AM - 1 Like   #11
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Some very good answers already.
Another thing is that.. well, that bird you mention will never be too giant. With wildlife, you will usually know how far you will be in advance. If you are too close for that prime, then it is usually a staged shoot or a park or a zoo. You will take 50mm or something like that for that type of shoot.
But out in nature, often even 500mm is not enough. People take shot with the longest lens they have, and then they add a TC and they crop in post.
Yet another factor is that if someone hires you to sit in bushes for hours and hours, you will probably take more than one camera with you. So you can have one with 500mm, one with 300mm. And probably an assistant with a 100mm and 50mm.

And you still have option of zoom lenses like 70-200mm or 150-500mm and so on. Telephoto zooms are becoming increasingly better and more affordable (or rather, you have multiple tiers to choose from, affordable, mid range, and top notch expensive stuff).
Finally, you can still switch lens if a large animal wanders too close. Though, if that happens, you usually need to get the hell away from it. If an animal is too big and too close for 500mm, it is probably dangerous.

So your question is not dumbass, its just that you most likely haven't sat in those bushes waiting for birds and giraffes enough.
that said, neither have I. I am not a telephoto shooter. But I do shoot primes, so I know their constraints and their pros and cons. Lots of little things to consider, not just the number of mm. And there will always be cases where you don't have the best possible lens for the shot, but you still have to make it work, somehow.

Last edited by Na Horuk; 07-12-2017 at 04:51 PM.
07-11-2017, 09:15 AM   #12
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Zoom lenses are more complicated lenses that require more glass elements and more moving parts than comparable prime lenses (those with only one "mm setting" of focal length).

The simple fact is: prime lenses are easier to design, cheaper to make, lighter in weight, and smaller in size than zoom lenses of comparable sharpness, distortion, contrast, etc.

And it doesn't help that in the past, lens technology simply could make a great zoom lens and so they have a lingering reputation problem even if some modern day zooms are excellent.

That's not to say good zooms are impossible these days but they will always be bigger, heaver, and more expensive than a prime. And zooms will often not have as large (bright) a maximum aperture as competing prime lenses.

Last edited by photoptimist; 07-11-2017 at 09:21 AM.
07-11-2017, 09:33 AM - 1 Like   #13
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A perfectly good question.

Single focal length lenses (primes) tend to be either smaller and cheaper or faster and better than similar focal length zooms.

As has been said, if you're after birds you must probably will never be too close.

For bigger animals, sure, you can easily get too close. Even on foot my 55-300 has been too long at times (elephants are big), and far more often in a car where animals can come right up to you. At those times you want a zoom or more than one camera.
07-11-2017, 09:37 AM - 3 Likes   #14
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Now that you mention it -- why don't we have 'zoom' hammers and screw drivers? Are adjustable wrenches 'zoom' tools?

Ohh, hey, an' my truck. A fixed horse power engine? Bummer! But the automatic transmission sort'a counts as a 'zoom-box' I suppose.
07-11-2017, 09:38 AM   #15
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I have a 55-300 WR that I use as a walk about in TAv. All versions of this lens are superb. As well I have a Sigma 150-500 which is also superb. I print 40" X 30" canvas off these and sell some. I have no reservations at all using a quality Zoom and Price wise the 55-300 can be had for a reasonable $. The Bigma is a little pricey. I also have primes but nothing over 100mm Macro WR that are excellent. The longer Zooms are just too versatile to ignore and the Quality is sellable.

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