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09-20-2018, 07:53 PM   #31
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QuoteOriginally posted by Andrea K Quote
SPOT or Select on central point are equal, at least on k-1, I checked. it's a bad translation or a wrong sense of the phrase.
QuoteOriginally posted by stevebrot Quote
I tend to agree. The phrasing is clumsy in regards to the comparison with "Select" setting, i.e. "a set of middle AF sensors in autofocus operation". Whether this refers to apparent size in the overlay or the actual sensor diameter is not clear.


Steve
Are you sure? This is the immediately preceding paragraph:

“Choose a focus point with the narrowest in-focus area
When you have a desired focus point in the image field, choose an AF setting with the narrowest in-focus area. For instance, when you set the AF mode to AF.S (Single), you have a choice of Auto, Zone Select, Select and Spot settings (in order from widest to narrowest areas).”

That reads as a clear, direct and emphatic statement to me, not a clumsy translation.

Combined with the distinction between ‘single’ and ‘set of’ in the following paragraph it reads to me as Pentax clearly saying Spot is smaller and more precise than Select-Center-Point.

“Highlight: The advantage of Spot setting in AF mode
The Spot setting is an autofocus mode that detects the in-focus point using a single AF sensor positioned at the center of the image field. For PENTAX digital SLR cameras marketed after the PENTAX K-3, the Spot setting detects an area approximately 30 percent narrower than that of the Select setting, which uses a set of middle AF sensors in autofocus operation.”


Last edited by monochrome; 09-20-2018 at 08:01 PM.
09-21-2018, 12:22 AM   #32
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Do some tests and report here the results.
09-21-2018, 05:04 AM   #33
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QuoteOriginally posted by Andrea K Quote
Do some tests and report here the results.
Do some tests and report here the results.
09-21-2018, 05:13 AM   #34
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QuoteOriginally posted by monochrome Quote
Do some tests and report here the results.
AF Spot mode: hidden fact revealed - AF point is 30% smaller than in "select" - Page 2 - PentaxForums.com

I have already done the tests... Would be very useful another test from another forum member

09-21-2018, 07:20 AM   #35
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QuoteOriginally posted by Andrea K Quote
AF Spot mode: hidden fact revealed - AF point is 30% smaller than in "select" - Page 2 - PentaxForums.com

I have already done the tests... Would be very useful another test from another forum member
I’m not the one contradicting Ricoh’s direct, published statement about how their AF works.

IMO your test cannot be controlled nor replicated. It is a subjective observation - a claim - based on local conditions and uses. I have neither the bench test tools nor the skill to prove the negative hypothesis you state.

I choose to believe RIcoh’s unambiguous, published statement. After all, they know what they designed.
09-21-2018, 07:23 AM   #36
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We could always try asking someone at Photokina next week. I would try (and will) at the booth, but I think none of the personnel will have the correct knowledge/information. The behind the screens interview that PF will(?) conduct might be a better place to ask this question.

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09-21-2018, 08:22 AM   #37
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QuoteOriginally posted by monochrome Quote
I’m not the one contradicting Ricoh’s direct, published statement about how their AF works.

IMO your test cannot be controlled nor replicated. It is a subjective observation - a claim - based on local conditions and uses. I have neither the bench test tools nor the skill to prove the negative hypothesis you state.

I choose to believe RIcoh’s unambiguous, published statement. After all, they know what they designed.
It's strange that this isn't in no one manual and testing it there isn't evidence but who cares we are speaking about millimeters. Ok I too will trust to RICOH.

Canon has a similar system but not restricted to central point.
09-21-2018, 08:45 AM - 1 Like   #38
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QuoteOriginally posted by Andrea K Quote
AF Spot mode: hidden fact revealed - AF point is 30% smaller than in "select" - Page 2 - PentaxForums.com

I have already done the tests... Would be very useful another test from another forum member
Here's a relevant thread - did your tests use this method?
How to check your AF "point" coverage / sizes - PentaxForums.com

In theory it would produce two different outputs with different sizes. I would suggest multiple tests using a tripod and a pan and tilt head to make it easier to control.

(For the record I have a K-3 so there isn't much point in my testing since the article says "after the K-3" this changed.)

09-22-2018, 10:47 AM   #39
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I realized that in the k-1 viewfinder the central point "indicator" has a different size between SEL on central point and SPOT. SPOT is smaller, then also this can confirm the statement in the RICOH site.

However I redo a quick test and I can't find any difference, perhaps I have to do a test with pan and tilt head.... with these dimensions we are talking about millimeters or maybe even less.
09-22-2018, 12:45 PM   #40
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Good read, and thanks.
I don't think (assuming) that the AF spot mode of the "after the K3" cameras would should such a difference in "tracking" vs. newer cameras such as the K3II and K3IIs.
But again, this would have to be tested and, according to some posters, not reproducible.

Last edited by jpzk; 09-22-2018 at 02:58 PM.
01-14-2019, 12:13 AM   #41
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That's all? Two articles and then stop? Is that the Pentax consistency of doing things?
01-14-2019, 12:56 AM - 2 Likes   #42
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QuoteOriginally posted by Ole Quote
RICOH has begun a series of "how to" articles on their home page under the heading Make the Most of Your Pentax Camera.

So far two are available:

- How to optimize focus accuracy with large aperture lenses
- The PENTAX Hyper Control System

These articles are well written and easy to read in part due to the illustrations provided. The articles are a useful supplement to the condensed information provided in the user manuals.

I hope we'll see more articles in this series.
There is a third one :

How do you optimize the finishing-touch settings for portraits?
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