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06-01-2016, 03:27 AM - 1 Like   #31
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QuoteOriginally posted by ogl Quote
35-80/4 for 645? I doubt.

there are 28-45/4.5, 33-55/4.5 and 45-85/4.5
new standard zoom in roadmap is approx.45-90...
But the 33-55 is old and the 28-45 is crop only, so it's for FF 645! You heard it here first!

Anyway, the size makes no sense, even if it includes flange distance (which I guess it must), it would indicate a minimum length of approximately 115 mm. That's quite a bit longer than the 28-105, and even a bit longer than the 24-70. It doesn't make sense.

06-01-2016, 03:42 AM   #32
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QuoteOriginally posted by gazonk Quote

Anyway, the size makes no sense, even if it includes flange distance (which I guess it must), it would indicate a minimum length of approximately 115 mm.
How did you calculate this?
06-01-2016, 03:59 AM   #33
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QuoteOriginally posted by ogl Quote
How did you calculate this?
The patent seems to indicate a minimum length of ~160 mm, minus the K-mount flange distance.
06-01-2016, 04:40 AM   #34
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It would be a 27 to 62 ish equivalent lens on the 645z. makes more sense to me. My 28-70 F4 is a lot more compact than this one.

06-01-2016, 04:45 AM   #35
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QuoteOriginally posted by D1N0 Quote
It would be a 27 to 62 ish equivalent lens on the 645z. makes more sense to me. My 28-70 F4 is a lot more compact than this one.
Why 27? 21-48...
06-01-2016, 04:54 AM   #36
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QuoteOriginally posted by ogl Quote
Why 27? 21-48...
Crop factor to FF is 1.28 not 1.66
06-01-2016, 05:15 AM   #37
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QuoteOriginally posted by OoKU Quote
L (length): 160.34 166.92 192.65
This is a very long lens for its specs. Far from any limited philosophy.

The lenght is probably the axis from the front element to the sensor. If the drawing are in scale, the front element should be about 55mm across and the distance from the rear element to the sensor about 48 mm, which seems very reasonable for the K mount focal flange distance. It would come in conflict with the mirror in a 645 camera.

The size doesn't make any sense to me. I guess something are lost in translation. Maybe its a 35-80 mm f/1,4 lens in stead of f/4,1

Last edited by Simen1; 06-01-2016 at 05:34 AM.
06-01-2016, 05:31 AM   #38
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QuoteOriginally posted by Zygonyx Quote
Yes, but rangewise overlapping with f/2.8 lenses, hence killing sales...

This 20-35/35-80/100-300 f/4 line'up, if confirmed, is quite interesting and makes sense as far as compactness and IQ are (potentially) concerned.
TBH I'd probably still pick a camera that has a 24-105 for it (or maybe 24-70). Fullframe DSLRs are already big and heavy, so there's little point (I think) in making smaller zoom lenses with awkward ranges. 20-35 would still be a nice range btw, and 100-300 too (that would be equivalent to a 70-200 on APS-C) but I don't see much use for that 35-80. I at least wouldn't want such a limiting zoom range as one of my most often used lenses.

Also, a 100-300/4 is not going to be compact.

I'm definitely for an all-f/4 line though. Just not for that 35-80.

06-01-2016, 05:35 AM   #39
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QuoteOriginally posted by Simen1 Quote
The lenght is probably the axis from the front element to the sensor. If the drawing are in scale, the front element should be about 55mm across and the distance from the rear element to the sensor about 48 mm, which seems very reasonable for the K mount focal flange distance. It would come in conflict with the mirror in a 645 camera.
Aha, well spotted.

QuoteQuote:
The size doesn't make any sense to me. I guess something are lost in translation. Maybe its a 35-80 mm f/1,4 lens
Now that would be something!
06-01-2016, 05:46 AM   #40
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QuoteOriginally posted by egami:
  • Patent Publication No. 2016-99586
    • Published 2016.5.30
    • Filing date 2014.11.26
  • Example
    • Zoom ratio (zoom ratio) 2.19
    • FNO. 4.1 4.1 4.1
    • Focal length f 36.11 51.17 79.07
    • Half angle of W 31.9 22.9 15.0
    • The image height Y 21.64 21.64 21.64
    • fB 48.06 55.95 58.90
    • Overall length L 160.34 166.92 192.65
Image height seems too low for 36*24 unless they mean radius: https://www.google.nl/search?num=30&client=firefox-b&q=21.64*2&oq=21.64*2&gs...30.mLFdwYxrJ3I

But still a big flange distance to the back element. It can be 38mm or something like that before hitting the mirror. Could this be a design adapted from 645?

Last edited by D1N0; 06-01-2016 at 05:59 AM.
06-01-2016, 06:29 AM   #41
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QuoteOriginally posted by gazonk Quote
(...)

But is it really a K-mount lens? What if it is a 645 lens?
像高, the Google-translation of which is 'image height', means the radius of the image circle when used in correlation with an optical formula.

21.64mm radius <==> 43.28mm diameter for the image circle, whilst the diagonal of a 24mm x 36mm rectangle is 43.27mm.
06-01-2016, 06:33 AM   #42
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QuoteOriginally posted by D1N0 Quote
Image height seems too low for 36*24 unless they mean radius:
Image height seems to always mean radius of the image circle in these patents. 21,64 mm corresponds to the distance from the center to the corner of the sensor, 21,633 mm (if we assume the K-1 sensor are exactly 36 x 24 mm, which probably only are an approximation).

Where did you get the 38 mm number from? The K mount focal flange distance is 45,46 mm and the K-1 mirror is lifted out of the way in a special move that doesn't leave much headroom for protruding rear elements.
06-01-2016, 06:52 AM   #43
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QuoteOriginally posted by Simen1 Quote
Where did you get the 38 mm number from?
This patent: Ricoh 100-300mm F4?????????????So-net???
06-01-2016, 06:55 AM   #44
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QuoteOriginally posted by johnmflores Quote
What benefits would the K-1 with a bag of F4 zooms have (if any) over a K-3 II with a bag of F2.8 zooms?
size and weight less... close to those of f/2.8 zooms on crop.
06-01-2016, 07:04 AM   #45
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Even when you deduct the 45.46mm flange distance you still get a 114.88-147.19 length The length of the D FA 28-105 is 86.5mm. Could it be a 1:1 Macro zoom?
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