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03-26-2015, 08:07 PM - 1 Like   #406
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QuoteOriginally posted by Class A Quote
Are you sure that you saw the weight of something being specified rather than its mass?

Since gravitational mass and inertia mass are equivalent, one can measure the mass of something by weighing it (and converting considering the gravitational field).

A scale for body weight on earth is not intended to report the force that your body produces in earth's gravitational field, but the mass of your body. Hence the unit used is "kg" not "N".

I suspect that in all your observations the unit "kg" is correctly used to express the mass of something.

The imprecision is only in everday language where people do not consider other gravitational fields (e.g., that on the moon) and therefore do not distinguish between weight and mass. That unawareness of the difference between these concepts probably exists just as much in countries that do not use metric systems, if only through lay people pretty much never using the unit for mass.


They use Newton-meter, of course, since only a force is involved.

Kilogram-meter, would only make sense if the force were created by a mass, which is typically not the case.
In my early university career, we still worked in the Imperial System of units, which was confounding to some in these matters. The lengths people went to, to rationalise the system, was quite baffling to the layperson, so it's no wonder there's still confusion abroad. If you've never heard of a poundal, and you don't have anything better to do, then look it up.

In a similar vein, there was an early attempt to rationalise the MKS System (pre-SI) and there was such a unit as the kilogram-force recognised in it. It was the force generated when accelerating one kilogram mass at 9.81 ms-2 (in other words, 9.81 N), but in order to distinguish it from a kilogram-mass, the subscript "f" was added to it. Sloppy people left that off, leading to further confusion and ultimately to the banning of its use in accredited tertiary programs.

Don't get me started on British Thermal Units...

03-26-2015, 08:11 PM   #407
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QuoteOriginally posted by clackers Quote
I think we might find a new show coming out of ITV next year ...
With Steve Coogan as host? Might as well get Rob Brydon in there make a whole show on their Michael Caine impressions...
03-26-2015, 08:32 PM   #408
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QuoteOriginally posted by Stavri Quote
With Steve Coogan as host? Might as well get Rob Brydon in there make a whole show on their Michael Caine impressions...
It would be Clarkson, shopping his services around, now he's been sacked. I have also heard Netflix as a rumour.

But Coogan would be good! :-)
03-30-2015, 02:31 AM   #409
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QuoteOriginally posted by Stavri Quote
Oooo weeeee.............Top Gear Slam!!!
Uh what? Jeremy Clarkson is starting a new show on photography gear reviews? "Top IQ Gear"... Strange thing is, I think I would actuall enjoy it too.

03-30-2015, 10:48 AM   #410
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QuoteOriginally posted by tuco Quote
Yes, it matters. See this book? It is full pre-solved beam and other equations good for both imperial and metric units. If you stick in "kilograms" for weight or force in any of these equations, you will get the WRONG answer both in units and magnitude.

What school of engineering did you graduate from that taught you a different metric system were weight and mass have both the same units and value? 1 kilogram of mass weighs 9.81 Newtons. Those don't look like the same numbers to me.
1.
In colloquial speech: weight = mass (polish: waga/ciężar = masa).
In Poland says: "Ja ważę 70 kg." I weight 70 kg. Does that mean: "Moja masa wynosi 70kg." But no one ever sayd like that.

2.
In school (old time, past time) kilogram was used as >newton/mass, then it was written by KG, not kg. So, kg=>mass, KG=>weight, and in colloquial speech (point,1,) is "old way".
03-30-2015, 01:13 PM   #411
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QuoteOriginally posted by Clavius Quote
Uh what? Jeremy Clarkson is starting a new show on photography gear reviews? "Top IQ Gear"... Strange thing is, I think I would actuall enjoy it too.
DigitalRev attempt this already, Clavius, if you've ever seen their YouTube clips.

Kai isn't Clarkson, the budgets are nothing, and the laughs are few, but the influence on style is there. :-)
03-30-2015, 01:21 PM - 1 Like   #412
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QuoteOriginally posted by clackers Quote
DigitalRev attempt this already, Clavius, if you've ever seen their YouTube clips.

Kai isn't Clarkson, the budgets are nothing, and the laughs are few, but the influence on style is there. :-)
Kai's channeling of Clarkson is painfully obvious indeed.......
03-30-2015, 01:23 PM   #413
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QuoteOriginally posted by Stavri Quote
Kai's channeling of Clarkson is painfully obvious indeed.......
Yep. I think the Cheap Camera Challenge segment (aka Celebrity ina Reasonably Priced Car) was pretty good, though.

03-31-2015, 12:05 AM - 1 Like   #414
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QuoteOriginally posted by clackers Quote
DigitalRev attempt this already, Clavius, if you've ever seen their YouTube clips.

Kai isn't Clarkson, the budgets are nothing, and the laughs are few, but the influence on style is there. :-)
Ha yes, I know Kai's video's. I like them, despite the critique and frowns they get from a lot of people. And despite trying to be like Clarkson, he does say a lot more usefull things about photography gear then Clarkson does about cars though.
04-01-2015, 05:46 PM   #415
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Who is Kai Clarkson?
04-01-2015, 06:51 PM   #416
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QuoteOriginally posted by Uluru Quote
Who is Kai Clarkson?
Jeremy Clarkson is the creator and chief presenter of BBC's irreverent Top Gear car series, which rose out of the ashes of the more serious Fifth Gear.

Kai (not sure of surname) is a wannabe fronting a Hong Kong camera retailer's YouTube channel.

Both have their moments. :-)
04-01-2015, 07:09 PM   #417
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Jeremy Clarkson was...
04-02-2015, 04:11 AM   #418
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To be honest I wonder whether Pentax should depart from it's K-? nomenclature in order to distinguish the FF camera from the inevitable K-3 successor models. K-FA isn't a bad idea. I think sometimes numbers remind people that their camera is an iteration on a previous design and will soon also be supersceded. K-FA would give the message that this is a new product and the name implies a degree of permanence.

There is a limited amount of true surprises that Pentax could include in the camera, we've already heard about the possible pixel-shifting technology and Pentax has had a patent on an EVF-OVF overlay for years. At this point we might see an additional development in the effectiveness of SR, five-axis?

I suppose one area of surprise that would be nice would be if Pentax had somehow implemented a new and exciting battery technology, but I don't know of anything in the market that would qualify and Pentax/Ricoh lack the expertise to do anything truly progressive in this area (as far as I know anyway).

I would think minor additions would include WiFi and maybe NFC (given the appearance of these in the K-S2). GPS would be a nice little extra to allow astro-tracing without the need for the external unit.

Overall, I can't see Pentax doing anything that radical. Solid yes, but radical no. Pentax works by small incremental improvement.
04-02-2015, 04:18 AM   #419
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So let's make it K-F
04-02-2015, 05:38 AM   #420
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QuoteOriginally posted by Zygonyx Quote
So let's make it K-F
Yes, that would work.
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