Cameras that automatically focus using phase detection have been aroun

Question

Cameras that automatically focus using phase detection have been around since the 1970s. However, these early auto-focusing cameras were slow and easily confused by low light and low contrast. In the 1980s, Japanese manufacturers introduced automatically focusing cameras that remedied these problems, and now professional 35 mm cameras have the ability to automatically focus and to quickly determine which of several possible subjects needs to be most in focus.

Which of the following statements can be inferred given the information above?

(A) Automatic focusing in today's professional 35 mm cameras does not use phase detection.

(B) In the 1980s, some camera manufacturers produced cameras that focused faster than some of the cameras manufactured in the 1970s.

(C) Cameras produced in the 1970s could not determine which of several possible subjects most needed to be in focus.

(D) Today's professional 35 mm cameras that focus automatically are never confused by low light or low contrast.

(E) If a subject is in insufficient light, a camera built today that focuses automatically will generally take a clearer picture of the subject than one that doesn't focus automatically .

tuanquang269 · Answer

1970 camera:   + using  , but   &  
1980 camera: FIX   +   &

QUESTION TYPE: Inference => Must be true

CrackverbalGMAT · Answer

let us look at the answer options -

A - cannot be inferred. all the author says is this - "Cameras that automatically focus using phase detection  have been around  since the 1970s." this statement implies that they are still around.

B - correct answer. read the argument carefully. "these early auto-focusing cameras  were slow  and easily confused by low light and low contrast. In the 1980s, Japanese manufacturers introduced automatically focusing cameras that  remedied these problems "
"some camera manufacturers" refers to "Japanese manufacturers".

C - Incorrect. "early auto-focusing cameras were slow and easily confused by low light and low contrast." - This only implies that they did not function very well in low light and contrast. this does not mean that they could not determine which of the subjects needed to be in focus.

D - Incorrect. "professional 35 mm cameras have the ability to automatically focus and to quickly determine which of several possible subjects needs to be most in focus." - this only means that they do a better job than previous cameras. Does not mean that they will never be confused by low light or contrast.

E - incorrect. "professional 35 mm cameras have the ability to automatically focus and to quickly determine which of several possible subjects needs to be most in focus." - all we can infer is that cameras today do a better job at focusing than previous cameras did.
Does not mention that today's auto focus cameras are better than today's cameras that do not have auto focus. Note that the argument talks only about auto focus cameras. Information about non auto focus cameras cannot be inferred.

ezzo · Answer

I fell for C. In this line "these early auto-focusing cameras were slow and  easily confused by low light and low contrast. " isn't author trying to say that the cameras used to get confused and not able to focus objects? 
and I ruled out option B because of some in it like how do we know that the Japanese manufacturers produced cameras that focused faster than  some  of the cameras manufactured in 1970. It could be all too?

Can anyone help me on this?

Octobre · Answer

I too would go for C because of "that remedied these problems, and now (...) and to quickly determine which of several possible subjects needs to be most in focus."

Prashant10692 · Answer

Straight B. 
Camera in 70's were slow and 80's camera remedied these problems.

akshata19 · Answer

Good Question

Let's eliminate options first

(A) Automatic focusing in today's professional 35 mm cameras does not use phase detection.

-fact given - 3 phase detection have been around since the 1970s.
So this is not true

(D) Today's professional 35 mm cameras that focus automatically are never confused by low light or low contrast.

-remedied the problems.. Yes but use of word never is extreme

(E) If a subject is in insufficient light, a camera built today that focuses automatically will generally take a clearer picture of the subject than one that doesn't focus automatically .

- the comparison should be Between 1970 & 1980
And please note that both were auto focus 
Here the comparison is btwn auto and non-auto focus hence not in scope

Let us elaborate B and C

The below line from passage is important to infer
'35 mm cameras have the ability to automatically focus and to quickly determine..which subject to focus'

(B) In the 1980s, some camera manufacturers produced cameras that focused faster than some of the cameras manufactured in the 1970s.

- okay the camera in 1980 could quickly determine subject to focus hence faster than 1970s model

(C) Cameras produced in the 1970s could not determine which of several possible subjects most needed to be in focus.

-it is mentioned that it could quickly determine no where we can conclude that 1970s they could not determine it is just mentioned that it was slow and get confused with lowlights

C is the ans

pkm9995 · Answer

Cannot agree with the answer.In my opinion all answer choices are wrong.

nightblade354 · Answer

Hi  pkm9995109794 ,

Let's analyze the argument. I too missed the key word, though I got the answer through POE.

Cameras that automatically focus using phase detection have been around since the 1970s. However, these early auto-focusing cameras were  slow  and easily confused by low light and low contrast. In the 1980s, Japanese manufacturers introduced automatically focusing cameras that  remedied these problems , and now professional 35 mm cameras have the ability to automatically focus and to quickly determine which of several possible subjects needs to be most in focus.

--  We are comparing cameras from the 1970s, to cameras from the 1980s, to cameras of today. 
-- Problems: 1970s: Poor light and contrast issues, but ALSO (in green) SLOW - I missed this part, because I read 'both problems' as confused and light contrast, but it is referencing those two, plus the slowness of the cameras. 
-- Solution: 1980s: Remedies ALL problems, therefore some HAVE to be FASTER than the SLOW models

(B) In the 1980s, some camera manufacturers produced cameras that focused faster than some of the cameras manufactured in the 1970s. -- Word for word out solution.

Does this help?

Helium · Answer

Since Japanese manufacturers in the 1980s remedied the 1970s problem that "auto-focusing cameras were slow," some of these Japanese cameras were faster, making B the correct response. Answer A is incorrect because we are never told that the later cameras didn't use phase detection. Choice C is wrong because nowhere does the argument say that the earlier cameras could not do this, though they may have done this more slowly and not as well as the later cameras did. "Never", in D, is too strong a word; they may get confused under some circumstances. The comparison presented in E is not supported by the passage.

assaad · Answer

OA and explanation
veritas prep level 650-700

Since Japanese manufacturers in the 1980s remedied the 1970s problem that "auto-focusing cameras were slow," some of these Japanese cameras were faster, making B the correct response. Answer A is incorrect because we are never told that the later cameras didn't use phase detection. Choice C is wrong because nowhere does the argument say that the earlier cameras could not do this, though they may have done this more slowly and not as well as the later cameras did. "Never", in D, is too strong a word; they may get confused under some circumstances. The comparison presented in E is not supported by the passage.

VerbalBot · Answer

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Cameras that automatically focus using phase detection have been aroun

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