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03-16-2016, 02:52 PM   #61
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QuoteOriginally posted by calsan Quote
......or just tumble down the limited prime lens rabbit hole......
And you'll meet a good few of us already down there at the bottom.

03-16-2016, 02:55 PM   #62
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QuoteOriginally posted by FantasticMrFox Quote
There is a reason a lot of pros use lenses like the Canon 24-70 f/2.8 - the image quality is outstanding, on one level with many primes, albeit of course not the best ones, and also not as fast. Since I got my Sigma 17-50 f/2.8 HSM I find myself hardly ever using my DA 35 f/2.4 any more. There might be a negligible difference in MTF test charts, but the real world difference is nil. The only reason I see to use primes over fast, high-quality zooms is a wider aperture for darker scenes or shallower depth of field.

And they certainly are very versatile. A 17-50 mm zoom saves you buying and changing at least three primes (20 mm, 35 mm, 50 mm). Sure, something like the 16-85 would be even more versatile (but with a slower aperture), but 17-50 is more than enough for me.
I understand. If you are doing one type of shooting that fits within the 17-50 range in a longer period then its a good choice. Same with other f/2,8 zooms. But your example also shows some of the trade off that is made. The Tamron 17-50 costs more then double of what the DA50 and DA35 costs combined, weighs almost double of DA50 and DA35 combined, and is around double the length. It also needs a far more complex optical formula with 16 lenses, with 4 special lenses, in stead of the 6 lenses used in DA50 and DA35. Still the Tamron can't offer the as large aperture. I have not checked optical benchmarks, but i know the Tamron are very good, probably comparable to the two Pentaxes at the same apertures.

On the other side the Pentax 18-135 f/3,5-5,6 WR are both lighter, shorter and cheaper then the Tamron, even with its weather sealing and longer reach, thanks to its smaller aperture.

I understand that these sets of compromises suits you and others. Its just not my preference.

---------- Post added 03-16-16 at 11:07 PM ----------

QuoteOriginally posted by normhead Quote
More zoom range could be the answer. More IQ could be the answer, but usually those two things are not answered by the same lens.
That brings me back to the reason I have an interchangeable lens camera. I like both, even if I can't have them on the camera at the same time.

QuoteOriginally posted by WPRESTO Quote
Tamron does make a FF compatible 28~300mm that is very moderately priced (about $370 in k-mount). Owner ratings on B&H suggest the lens has decent performance (about 4.5 out of 5 by Canikon, Sony and Pentax users)
I was actually thinking of the newer version that I hope will come with k-mount.
03-16-2016, 03:42 PM   #63
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QuoteOriginally posted by normhead Quote
Have you considered that the filters make hardly any difference at all, and that you might be totally over-reacting?
They make a difference to my wallet - and how am I overreacting? I am not exactly emotionally invested in this topic.
03-16-2016, 04:42 PM   #64
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QuoteOriginally posted by FantasticMrFox Quote
They make a difference to my wallet - and how am I overreacting? I am not exactly emotionally invested in this topic.
The wallet thing works until it doesn't, and it cost you money for not having one on, so even that's not a given.

QuoteQuote:
I am not exactly emotionally invested in this topic
Whatever....

03-17-2016, 11:33 PM   #65
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QuoteOriginally posted by Simen1 Quote
The zoom factor of this class of lenses have been increasing from time to time. The last decade from 18-200 to 18-250 to 18-270 to 18-300 to 16-300. What is next? 15-300 or 16-320 (both 20x)? Maybe we get a Pentax 15-300 or thereabout in the near future, or a 28-300 for FF or both.


A WR 16-320 or 15-300 would be something I would wish for. But, I would also wish for un upgrade of the HD 55-300. I wish Pentax would come up with an 80-400 APS-C lens with a wider opening say f/3.5 and a very much faster AF. It would be a great match for the 16-85 WR. But again, I'm just wishing.
03-18-2016, 12:08 AM   #66
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QuoteOriginally posted by totsmuyco Quote
I wish Pentax would come up with an 80-400 APS-C lens with a wider opening say f/3.5 and a very much faster AF.
Sorry to burst the balloon but consider this.

Sigma makes an 80-400 f4-5.6. It is about 95mm in diameter and weighs about 1750g.

Nikon has an 80-400 f4.5-5.6, which is similar in size, weighs about 1570g and costs about $7,000.

The Canon 400mm f4 is about 127mm in diameter, weighs almost 2kg, and costs about $5,700.

The Canon 200-400 f4 (with built-in 1.4x extender) is about 128mm in diameter, weighs about 3.6kg and costs about $10,000.

Unless someone comes up with radical new lightweight materials, or a radical new design, what are the chances of an xx-400 f3.5 being as compact, lightweight and affordable as an 18-300 superzoom??

Last edited by Des; 03-18-2016 at 01:08 AM.
03-18-2016, 01:27 AM   #67
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Anyone who must have a superzoom that is sharper than it has any right to be for $600 should check out the Nikon Coolpix P900. 24-2000mm (35mm equivalent) zoom. 16MP on a 1/2.3" CMOS sensor.

03-18-2016, 01:57 AM   #68
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QuoteOriginally posted by Des Quote
Sorry to burst the balloon but consider this.

Sigma makes an 80-400 f4-5.6. It is about 95mm in diameter and weighs about 1750g.

Nikon has an 80-400 f4.5-5.6, which is similar in size, weighs about 1570g and costs about $7,000.

The Canon 400mm f4 is about 127mm in diameter, weighs almost 2kg, and costs about $5,700.

The Canon 200-400 f4 (with built-in 1.4x extender) is about 128mm in diameter, weighs about 3.6kg and costs about $10,000.

Unless someone comes up with radical new lightweight materials, or a radical new design, what are the chances of an xx-400 f3.5 being as compact, lightweight and affordable as an 18-300 superzoom??


As of now, the 150-450 looks good but really weighs a lot. I normally carry 2 cameras, one for the short zoom and the other for the long end. Well, like I said, I'm just wishing. And like you said, I hope someone comes up with radical new lightweight materials or a radical design that can make an 80-400 compact. Bigger than the 55-300 but not too much.


Last edited by totsmuyco; 03-18-2016 at 01:59 AM. Reason: spelling
03-18-2016, 02:34 AM - 1 Like   #69
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QuoteOriginally posted by normhead Quote
The wallet thing works until it doesn't, and it cost you money for not having one on, so even that's not a given.



Whatever....
For what it is worth, I was taking photos when my younger son turned five.

This is with a UV filter on:



This is with the UV filter off:



Now, the light was turned on between the photos, but the flare didn't go away because of that. The filter in question is a multi coated Hoya filter. I am not a big fan, but my wife is afraid of breaking or scratching lens front elements and so it is on there. If I don't shoot into direct intense light, I don't notice a difference, but there are certain situations where having a filter on is problematic. And this isn't even a cheap one.
03-18-2016, 04:15 AM   #70
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My 10 year old 180 buck Sigma 70-300 at about 200mm
and my Sigma 18-250 at 250mm.
Either one gets the job done for my purposes.
But then I have no fetish about "sharpness" - whatever that means.

Last edited by wildman; 03-18-2016 at 02:53 PM.
03-18-2016, 04:34 AM   #71
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V-A-V weight in a long-range zoom. The critical component for reducing weight may be the lenses. 12-15 pieces of glass, some quite thick, must be a substantial part of the weight. Plastic is lighter, and plastic lenses exist. I suspect a long-range zoom zoom with 100% plastic lenses would be significantly lighter than the same zoom with all glass lenses, but is technology anywhere near replacing glass with plastic in high IQ camera lenses? Does any optical plastic have the refractive properties of ED or fluorite glass? Is it possible to make plastic lenses equivalent in quality/precision to glass lenses? SFAIK plastic must still be molded, not ground. In theory, that should make it easier to produce complex aspheric plastic lenses, but can a precision lens be molded rather than ground?. Glass can be molded, but SFAIK lenses for high-end cameras are never made that way. My point: unless technology can find a way to substitute plastic for glass in zoom lenses, which will probably involve a major breakthrough enabling precision molding replacing grinding to fabricate precision lenses (never achieved SFAIK in the long history of glass manufacture), then it will not be possible to greatly reduce the weight of zoom lenses with upwards of 15 optical components.
03-18-2016, 04:44 AM   #72
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QuoteOriginally posted by WPRESTO Quote
Does any optical plastic have the refractive properties of ED or fluorite glass?
I don't know the tech details but I do know that my wife's fluorite corrected $2000 Zeiss 7x42 binos have 4 plastic elements in it (two in each barrel).
03-18-2016, 05:21 AM   #73
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Yes, but that is in binoculars using your eyes. Eyeglass lenses are and have been plastic for decades (I've wondered: are these molded or ground and polished?). If binoculars had IQ suitable for photographic purposes, they would long since have become the ultimate light/compact long FL lenses for cameras.* The Contaflex, a very successful 35mm camera, had a monocular (1/2 a Zeiss binocular) attachment that served as a long telephoto (8X = 400mm equivalent as I recall). Except in advertising, I never saw an image taken with one. I have high-end (=ED glass) Nikon binoculars so I know what they are like. Try this experiment: focus the Zeiss on something like a street sign, then slowly swing so the sign is at the edge of the visual field. What you see with your eyes is quite different from the appearance of a photographic image on film or from a memory card put up on a high-res monitor.

*Considering the length of time that eyeglasses have been plastic, I've always assumed that the process by which they are made is not suitable for making photographic-quality lenses. Plastic, I think, can be made with almost any refractive property (= could be made with the refractive index of crown. flint, ED or fluorite glass, or something that does not exist in glass).
03-18-2016, 05:37 AM   #74
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QuoteOriginally posted by Rondec Quote
For what it is worth, I was taking photos when my younger son turned five.

This is with a UV filter on:



This is with the UV filter off:



Now, the light was turned on between the photos, but the flare didn't go away because of that. The filter in question is a multi coated Hoya filter. I am not a big fan, but my wife is afraid of breaking or scratching lens front elements and so it is on there. If I don't shoot into direct intense light, I don't notice a difference, but there are certain situations where having a filter on is problematic. And this isn't even a cheap one.
Note to self, with a light source in the frame, be sure an use a polarizer.

There are many types of filter guys, just saying..
03-18-2016, 06:16 AM   #75
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QuoteOriginally posted by normhead Quote
Note to self, with a light source in the frame, be sure an use a polarizer.

There are many types of filter guys, just saying..
Why would you use a polarizer filter? I mean these are iso 3200 shots and I don't think a polarizer will reduce this flare. I find polarizers to be more useful for reflections from glass or water.
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