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08-07-2014, 05:51 PM   #1
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645Z tested in Popular Photography.

Not a bad test. They seemed impressed by the amount of resolution this camera is capable of...in fact it seems to be at the top of the heap. The heap includes full framers and other current medium formats.

Also Ricoh has a inside back cover advert for the 645Z. This is an expensive advertising and highly desired spot. Good for Ricoh.

08-07-2014, 05:53 PM   #2
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Isn't it amazing how the world works? Pay top dollar for an ad and the magazine's reviewers look after you.
08-07-2014, 08:55 PM   #3
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QuoteOriginally posted by lesmore49 Quote
Not a bad test. They seemed impressed by the amount of resolution this camera is capable of...in fact it seems to be at the top of the heap. The heap includes full framers and other current medium formats.

Also Ricoh has a inside back cover advert for the 645Z. This is an expensive advertising and highly desired spot. Good for Ricoh.
It better be able to out-resolve 36x24, the sensor is 30% larger !

Not surprised it's better than full-frame. Surprised it rated better than other medium format cameras, I would've figured it to be about the same... depending on lens of course.
08-08-2014, 01:29 PM   #4
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QuoteOriginally posted by ElJamoquio Quote
It better be able to out-resolve 36x24, the sensor is 30% larger !

Not surprised it's better than full-frame. Surprised it rated better than other medium format cameras, I would've figured it to be about the same... depending on lens of course.
According to the review a full frame sensor is 864 square mm. 30% of 864 is 259. The size of the 645Z sensor is 1,452 square mm. 864 + 259 do not equal 1,452. I believe that approximately 70% larger than a FF sensor is the correct statement.

What I found impressive about the review was that in terms of resolution, the Z at ISO 102,400 delivered 3425 lines of measured resolution, essentially equalling the D800 and a7r resolution measurements at ISO100.


Last edited by CDW; 08-08-2014 at 01:51 PM.
08-08-2014, 02:24 PM   #5
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QuoteOriginally posted by CDW Quote
According to the review a full frame sensor is 864 square mm. 30% of 864 is 259. The size of the 645Z sensor is 1,452 square mm. 864 + 259 do not equal 1,452. I believe that approximately 70% larger than a FF sensor is the correct statement.
You are talking about area. 1452/864 = 1.68 = 1.296^2.

That 1.296 = 29.6% larger on the diagonal, or colloquially, 'linearly'.



QuoteOriginally posted by CDW Quote
What I found impressive about the review was that in terms of resolution, the Z at ISO 102,400 delivered 3425 lines of measured resolution,
Now you are talking in terms of resolution on a linear basis, as almost all tests report. The appropriate scaling factor on this measurement is lp/ph. We might expect that to be the 29.6% above, but because of the differences in aspect ratio the actual number is 37.5%. All else the same, we'd expect the 645Z to measure 37.5% better than a 24mm tall sensor.
08-08-2014, 03:07 PM   #6
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Do you have a link for this review? All i see at there website is what they published back on April 14th....
08-08-2014, 03:35 PM   #7
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QuoteOriginally posted by ElJamoquio Quote
You are talking about area. 1452/864 = 1.68 = 1.296^2.

That 1.296 = 29.6% larger on the diagonal, or colloquially, 'linearly'.





Now you are talking in terms of resolution on a linear basis, as almost all tests report. The appropriate scaling factor on this measurement is lp/ph. We might expect that to be the 29.6% above, but because of the differences in aspect ratio the actual number is 37.5%. All else the same, we'd expect the 645Z to measure 37.5% better than a 24mm tall sensor.
Yes, I was talking about size of area, as I assume were you when you used the term 'larger'. As for resolution differences, I find it amazing the Z can deliver such measured resolution at extremely high ISO.
08-08-2014, 04:23 PM   #8
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QuoteOriginally posted by CDW Quote
Yes, I was talking about size of area, as I assume were you when you used the term 'larger'. As for resolution differences, I find it amazing the Z can deliver such measured resolution at extremely high ISO.
99% of resolution discussions are normalized to a linear dimension.

08-08-2014, 04:40 PM   #9
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QuoteOriginally posted by ElJamoquio Quote
99% of resolution discussions are normalized to a linear dimension.
You discuss it however you wish.:-)
08-08-2014, 05:32 PM - 2 Likes   #10
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QuoteOriginally posted by ElJamoquio Quote
99% of resolution discussions are normalized to a linear dimension.
99% of all statistics are Bull$hit.
08-08-2014, 06:59 PM   #11
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QuoteOriginally posted by Winder Quote
99% of all statistics are Bull$hit.
Very true. The truth as seen by the eye is often more relevant, particularly the RAW files I've seen and processed from a friend's 645Z. I haven't played with the very high end Phase or Hasselblad systems but in terms of noise, or lack of, and detail, the Z files are leaps beyond anything I've seen from a high megapixel FF DSLR. But that's my evaluation and my customers often buy very large prints. Even so, at lower ISO settings, my 645D still holds up. The extra 10 megs or so of the Z, don't buy that much of a visual gain in perceived clarity or resolution.
08-08-2014, 07:23 PM   #12
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Technicalities apart ... I hear the 645Z gives some pretty amazing images !
08-08-2014, 07:25 PM   #13
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QuoteOriginally posted by CDW Quote
You discuss it however you wish.:-)
I'll discuss it either way, I'm just following your lead to make it easier on you.
08-09-2014, 03:42 AM   #14
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QuoteOriginally posted by ElJamoquio Quote
I'll discuss it either way, I'm just following your lead to make it easier on you.
Don't overstress your ego on my account. :-)
08-24-2014, 11:46 AM   #15
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Saw the magazine cover today at the grocery store... I figured hell had frozen over seeing the Pentax solo on the cover. Good choice, though. I've never figured out the logic behind the photo mags only covering 2-3 brands. It's like a gun or car magazine only covering a couple manufacturers and leaving the rest to rot. Not good for the brands, the mag, the Readers and the person trying to find their way into a new hobby. That Pentax deserves a cover, so good to see.
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