Old Pentax 70 Zoom

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fencer

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Hi all,

I have a couple of questions about Pentax 70-Zoom.

It's probably the 1st or 2nd series and it looks exactly like the one shown here: http://stareaparaty.pl/aparaty/pentax-zoom-70/

There are three buttons on the front panel - one with a flash icon, one with a small sun icon and one with a clock icon (which most probably enables the self timer).

There is also a small LCD on the top of the case, but it only indicates number of shot frames.

How do I know if the flash is enabled or disabled? What does the sun icon mean?

How to check if the AF works properly? I can't hear anything when I try to press the shutter release halfway, and the AF motors are usually pretty noisy.

The battery is fresh of course.

Can't find any user manual online.
 
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How to check if the AF works properly? I can't hear anything when I try to press the shutter release halfway, and the AF motors are usually pretty noisy.
You might not find the answer to this one on the manual, so here it goes:
P&S cameras normally employed an active AF system, while SLR (that you probably are used to) use a passive system.
The Active AF system works this way: when you press the shutter button halfway, the system emits an infared beam through one window. The beam hits the subject and it is reflected back to another window. The time it takes to travel to the subject and back gives the system the distance to subject and that value is locked into memory.
When you press fully the shutter button, the AF motors put the lens in the right distance and the photo is taken. This system has a disadvantage: there is a delay between pressing the button and the shutter actually firing. That's why they aren't suitable for fast action shots.
You can read a bit more about the different systems here: http://en.wikipedia.org/wiki/Autofocus
 

AgX

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A basic idea about the working of an autofocus can be got by watching the front element move.

A better insight you get by checking the focus in the film plane (if possible) or by exposing a film.
 

AgX

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The Active AF system works this way: when you press the shutter button halfway, the system emits an infared beam through one window. The beam hits the subject and it is reflected back to another window. The time it takes to travel to the subject and back gives the system the distance to subject and that value is locked into memory.

The time lag is used at acustic active systems. Optical active systems use triangulation.
 
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fencer

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Ricardo, that seems to be the case. The lens move only when I press the button all the way down and the shutter fires.

A basic idea about the working of an autofocus can be got by watching the front element move.

A better insight you get by checking the focus in the film plane (if possible) or by exposing a film.

Wouldn't know how to check the focusing performance without a film, since there's no B setting...

Thank you all for you advice and links.
 

AgX

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Some point&shoot cameras have a long-exposure (though not B) setting. I do not know if such would be sufficient fot focus check. One might have to do some tricks to make it release at all.
 
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The minimum shutter speed is 1/40s. That is a bit tight to check for focus. The best way is still to shoot a test roll and try to use all functions to check if they work as advertised.
 
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That is the original IQZoom, the first in a long line of Pentax Espio/IQZoom cameras. It has an exceptional lens, and outstanding macro capability for an early compact AF camera. Expect good results from it.
 
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