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07-11-2017, 10:10 AM   #16
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I almost always carry a second body when using my DA*300mm and HD 1.4X RC. As others have mentioned, you are rarely close enough when shooting birds. The extra image quality of the prime is better for heavy cropping.

07-11-2017, 10:31 AM   #17
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When I read pop photo almost 30 years ago, zooms were already some of the best lenses. but cheap zooms were awful. Hence the "zoom" reputation. Good glass isn't a lot better but cheaper glass is light years better.

So basically you're asking me, why I use my Tamron 300 ƒ2.8. And that's pretty simple. You can't get 300 2.8 in a long zoom. If you want the big glass on the front, you have to carry the weight. I also have a DA* 200 2.8. I can stack TC's on it and take it right out to 476mm, and still be under 2 pounds and ƒ6.3. I often carry the DA*60-250 with my kit, but the max for it is one TC. If I use the 1.7 that gives me 425mm at ƒ6.3. So ƒ 4 makes a difference.

There is simply no way to make a zoom as efficient asa prime when you consider weight and aperture as your main priority. You sacrifice weight and ƒ -stops for versatility. And the design constraints in building a good zoom often mean they aren't the same IQ over their whole range. Zooms like the 60-250 that are good everywhere in their zoom range are expensive and rare. What folks, myself included do, is we set up the big fixed focal length on the tripod, (in my case the 300 3.8 with the 1.7 TC for 510 at ƒ4.5) and then have a second body with something like a 60-250 around our necks on a strap. There are too many times when one or the other is the best option, you have to hedge your bets and give yourself a chance.

Last edited by normhead; 07-12-2017 at 07:39 AM.
07-11-2017, 10:45 AM   #18
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I have a Pentax 16-85 lens and a Sigma 150-500 DG OS lens for Pentax. They both have given me excellent images using them on my Pentax cameras. The versatility of the zooms is an asset. There are scenarios where they allow composition of scenes that would not be available with a prime (fixed lens). A prime can be valuable, such as the 50 mm you have, where you have room and are able to position yourself for the shot. Otherwise, with enough light, a super zoom (example 150-500) is going to provide the flexibility to give you opportunities to have enough field of view to track wildlife. The short-medium zoom (example 16-85) will give you composition capability that you otherwise would not have, and along with a tripod the ability to shoot landscape (longer exposure) will aid in allowing enough light at higher F stop numbers (example F16, F18) while staying at a stable ISO (example 100, 200).

Fast primes can be useful, and handle some light situations that some zooms cannot, but there are also fast zooms, such as the Pentax 15-30, 24-70, and 70-200.

A lot depends on what you plan to shoot and what type lens will handle most of the situations that are in the planning.

Last edited by C_Jones; 07-11-2017 at 10:54 AM.
07-11-2017, 11:04 AM   #19
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QuoteOriginally posted by redridinghood Quote
Sorry, I know this is a stupid question.
It's not a stupid question. Unfortunately, subject distance is something that varies more greatly than any focal length would allow. The truth is that we miss the shots either because the subject is too far (more often than not) and sometimes because the subject is too close (that seldom happens when using a zoom such as the DFA150-450, because you can always zoom back down to 150mm). We keep the subjects that somehow fit the frame, or fit a cropped frame. One thing that allow good (or even very good framing) of the subject knowing where animals go and what time to see them and setup of hide which pretty much defines the distance to subject. For example, kingfishers perform fishing routines going from branch to branch near their nesting area. We just have to stay there for a while, observe their routine with binoculars from far away and setup a hide typically in the range of 4 to 8 meters from a most used perch, come install the K1 and DFA150-450 behind the camo nets and wait for a couple or hours to see this guy looking down in the water from a perch and AF and click the shutter fast enough before he decides to dive to catch his meal.

07-11-2017, 11:52 AM - 1 Like   #20
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QuoteOriginally posted by C_Jones Quote
Fast primes can be useful, and handle some light situations that some zooms cannot, but there are also fast zooms, such as the Pentax 15-30, 24-70, and 70-200.
The 31m 43 and 77 ltd are 1.8. My FA 50 is 1.7. There are a lot of primes that will give you more than a stop advantage over the fastest zooms. The 55 1.4, 50 1.4 and coming 85 and 50 will give you a two stop advantage. I always say if you can't fake a stop, you aren't a photographer, but over one stop you need to change lenses. There simply are no 1.4 zooms. Lets not make it sound like a zoom can do anything a prime can do, They can't. Just to be clear, for low light, primes are clearly superior. Even ƒ4 zooms can be less than functional in low light, in terms of both enough light for a decent shutter speed, and AF speed. I've been there enough with the ƒ4 60-250 to know how real this is. And most zooms are considerably slower than f4 in the long end. Quite simply stated, ƒ4 is too slow for many golden hour situations. It's all question of cost.

I'm as big a fan of using zooms where possible and efficient as anyone. In low light, I switch to primes, not because I want to, because in many situations I have to. It's either that, or lose the shot. My moto has been cover your range with zooms, fill in the important gaps with fast primes. Unfortunately it's not about IQ, it's about your ability to acquire an image at all. The downside to the wrong take here is missed opportunites.

I would say the biggest factor in folks wondering why their camera doesn't work the way they think they should is slow lenses. Slow speed wise and slow in terms of too small an aperture to shoot in the available light.

Last edited by normhead; 07-12-2017 at 07:40 AM.
07-11-2017, 12:52 PM   #21
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QuoteOriginally posted by pacerr Quote
Now that you mention it -- why don't we have 'zoom' hammers and screw drivers? Are adjustable wrenches 'zoom' tools?
They are.
07-11-2017, 01:22 PM   #22
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The reasons to use primes over zooms (in general) have to do with smaller size, sharper, and faster apertures.

As for using really long telephoto primes, you have to know what you are taking photos of and how close you can get. With most birds, 500mm is not going to be too long and even with that, you probably will be cropping a bit to fill up the image with the bird.
07-11-2017, 04:45 PM   #23
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QuoteOriginally posted by redridinghood Quote
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.
thanks
Essentially you are right, a zoom such as the Pentax 250-600 is much more convenient. But zooms are either larger or slower, or both, so it becomes a balancing act. At the end of the day your good technique and ability to predict where and when to be are the key to being successful with such shots.


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07-11-2017, 06:12 PM   #24
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If you're talking about wild birds, you're almost never too close to use a 500mm lenses, especially if you want to use the entire "full" frame image circle. They're just not tame enough to allow close approach, unless you stake out a nest and construct a blind bit by bit over the course of a week so as not to spook the bird. As far as zooms incorporating longer focal lengths than 500mm, portability of the lens and of a tripod large enough to hold such a rig steady is one limitation. The other is cost.
07-11-2017, 08:07 PM   #25
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Warning math involved

i will use my standard answer here

image size = subject size X focal length / distance

For a bird the length may go from 40mm for a hummingbird to , in North America , as a reference 3.3 meters for the wingspan of a California condor so yes the subject can be highly variable in size, but unless tame and tethered, just how close do you think you can get to a condor in flight? Even with 600mm focal length and assuming a crop sensor with width of 24mm as the image size, you need to get to 82 meters. That's pretty close even for a condor in Grand Canyon, at the south rim. I know, I've been there.

Now for a hummingbird, with the same 600mm lens,my ou need to be within 1 meter to fill the frame, that's great except a 600 mm lens is likely not to focus below 20-30 meters so you are cropping big time, no matter what.

So a 600 for all but general close work from a blind that is staked out for days is always too short
07-12-2017, 12:53 AM   #26
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QuoteOriginally posted by normhead Quote
The 31m 43 and 77 ltd are 1.8. My FA 50 is 1.7. There are a lot of primes that will give you more than a stop advantage over the fastest zooms. The 55 1.4, 50 1.4 and coming 85 and 50 will give you a two stop advantage. I always say if you can't fake a stop, you aren't a photographer, but over one stop you need to change lenses. There simply are no 1.4 zooms. Lets not make it sound like a zoom can do anything a prime can do, They can't. Just to be clear, for low light, primes are clearly superior. Even ƒ4 zooms can be less than functional in low light, in terms of both enough light for a decent shutter speed, and AF speed. I've been there enough with the ƒ4 60-250 to know how real this is. And most zooms are considerable slower than f4 in the long end. Quite simply stated, ƒ4 is too slow for many golden hour situations. It's all question of cost.

I'm as big a fan of using zooms where possible and efficient as anyone. In low light, I switch to primes, not because I want to, because in many situations I have to. It's either that, or lose the shot. My moto has been cover your range with zooms, fill in the important gaps with fast primes. Unfortunately it's not about IQ, it's about your ability to acquire an image at all. The downside to the wrong take here is missed opportunites.

I would say the biggest factor in folks wondering why their camera doesn't work the way they think they should is slow lenses. Slow speed wise and slow in terms of too small an aperture to shoot in the available light.
"The 31m 43 and 77 ltd are 1.8."

My 43mm is f 1.9.
07-12-2017, 07:38 AM   #27
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QuoteOriginally posted by ivanvernon Quote
"The 31m 43 and 77 ltd are 1.8."

My 43mm is f 1.9.
Next time I'll just say sub 2.
07-12-2017, 08:01 AM   #28
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QuoteOriginally posted by normhead Quote
Next time I'll just say sub 2.
Confuses me too. I always remember that one of the triumverate is 1.9 but I always have to go to the lens cabinet to remind myself which one it is. :>)
07-12-2017, 12:46 PM   #29
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to give you an idea of what a longer lens does
this a house finch at twelve feet from sensor to bird and a robin at twenty seven feet (I actually taped it out of curiosity)

k-3 + 150-500 sigma

if you want a relatively inexpensive way to experiment
find any of the pentax 55-300 lenses

I've never liked the sigma or tamron 70-300 lenses but they are cheap (used)
that said...the first bird photo I ever had published was taken with a tamron...go figure

I added the robin and one his buds at thirty feet but using 270mm instead of 500mm (same lens)

I hope that gives you something to work with
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Last edited by ccc_; 07-12-2017 at 01:40 PM.
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