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02-23-2012, 02:10 PM   #31
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LOL eddie, you have an excellent camera already...i've been wanting to do a night series and this body+fisheye is actually perfect....i just have to start the project...i love night shooting but with big gear the attraction factor is too high.

Night shooting with this on a little manfrotto should give some good images.

02-23-2012, 06:28 PM   #32
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Interesting post and interesting link!

However, I am not sure if I like what I see. The first ebay auction contains MTF charts at f/1.1 f/2 and f/4 for 10, 20 and 40 lp/mm, at f/4 for 100 lp/mm too (MTF50 at f/4 is 100 lp/mm). The lens clearly has its sweet spot closer to f/4 than f/2. The figures make me worry a bit.

A lens for a sensor this small must perform best below f/2.8, not above. The Pentax prime performs better at f/2 than f/4 and this must be so to resolve the tiny pixels (cf. photozone).

I advice to await first true user tests before ordering the lens. It may be a design not optimally suited for the tiny sensor.


WRT to equivalence, please read my recent paper
-> http://falklumo.blogspot.com/2012/02/camera-equivalence.html

An equivalent f/6 lens is an equivalent f/6 lens, nothing makes it gather more light than this. Light gathering capability is defined by the lens aperture surface only.
02-23-2012, 07:52 PM   #33
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Hence my "guinea pig" mention, i couldn't read that dam chart but i'm glad you chimed in. I should be getting my copy sometime next week.
Are there any specific tests situations you'd like to see? A list that myself and the other two, deanM3 and jgoldstein2000 can participate in?
02-23-2012, 08:38 PM   #34
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I picked up one, cant wait for it to come in...

02-23-2012, 09:11 PM   #35
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QuoteOriginally posted by bmonki Quote
I picked up one, cant wait for it to come in...
lol did you just pick up the one listed from SK Photo?

someone over at Photorumours has one for M43 (made for the GF1) which i thought weren't going to be sold? similar design supposedly (i dunno) but he has one ( i think the only one made)

Now i'm even more eager as in every forum everyone is basing their negatives over the size of the sensor not the photos it can produce
02-23-2012, 09:34 PM   #36
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QuoteOriginally posted by Clicker Quote
lol did you just pick up the one listed from SK Photo?

someone over at Photorumours has one for M43 (made for the GF1) which i thought weren't going to be sold? similar design supposedly (i dunno) but he has one ( i think the only one made)

Now i'm even more eager as in every forum everyone is basing their negatives over the size of the sensor not the photos it can produce
Na i picked up one from the original link when it was first posted, i was gone camping just got back...
02-23-2012, 09:37 PM   #37
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ah okay, deanM3 got the 3rd one then and where did jgoldstein2000 get his then? lol
nevermind i think i read that post wrong, he's getting a triplet

alrighty then post up as they come in then
02-23-2012, 10:36 PM   #38
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I'm looking forward to this!

02-23-2012, 10:44 PM   #39
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QuoteOriginally posted by deanm3 Quote
DOF is equivalent to 5.6 on FF, but light gathering ability is still equal to 1.1, correct?
No.

There is no difference between "DOF f-stop" and "light gathering f-stop".

Falk has answered this one already, but maybe not directly enough to be noticed.
02-24-2012, 01:14 AM - 1 Like   #40
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QuoteOriginally posted by Class A Quote
No.

There is no difference between "DOF f-stop" and "light gathering f-stop".

Falk has answered this one already, but maybe not directly enough to be noticed.
I have to disagree.

That statement considers only the total amount of light entering the lens, not the light intensity at the sensor needed for a given exposure which is how the concept of f-stop is used by photographers. With the same subject, perspective, light level, sensor sensitivity, shutter speed, and f stop, you will get equivalent exposures regardless of sensor size. That's why the rules for exposure are the same for all formats. There is no format setting that needs to be taken into account on an external exposure meter.

If what you state is the case, then if you took any camera and lens and aperture/shutter/ISO settings, with a given Ev, and the same grey card subject at a given distance, and take a "correct" exposure with the full sensor, then mask off the sensor so 1/13 of the sensor area is exposed, you'd have to increase shutter speed or ISO by about 5.5 stops to get the same exposure on the masked sensor, and that's just not true. The exposures for the exposed area on the masked sensor and the same area of the unmasked sensor would be the same with the same shutter speed.

f-stop is the ratio of the entrance aperture diameter to the FL of the lens. Film or sensor format does not enter into the equation.

Scott
02-24-2012, 02:27 AM   #41
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I have to agree with Scott.
This is actually one of the advantages of Q. It provides decent IQ with high ISO and yet you can use f1.1 lens and have the DOF of f5.6.
That's nothing short of amazing.
02-24-2012, 03:16 AM   #42
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Also available in Japan from mapcamera:

39.900 (approx. $495)

Bokeh sample pictures:

http://news.mapcamera.com/media/62/29q-1.jpg
http://news.mapcamera.com/media/62/29q-2.jpg
http://news.mapcamera.com/media/62/29q-3.jpg

WRT exposure:
Equivalence
QuoteQuote:
[...] the concept of Equivalence is controversial because it replaces the paradigm of exposure, and its agent, f-ratio, with a new paradigm of total light, and its agent, aperture [...]
Exposure
QuoteQuote:
[...]However, in cross-format comparisons, the density of light falling on the sensor (exposure) is absolutely meaningless [...]
02-24-2012, 05:09 AM   #43
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Thanks for digging up the samples and explanation but not so much on the price lol
02-24-2012, 07:16 AM   #44
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Just checked my tracking:

2012/02/24

08:33

MISSISSAUGA

International item arrived in Canada and will be reviewed by Customs


it's almost in my hands, soon i'll be pacing the front door like a sentry on guard

I'm on my desktop so i did the rough translation via BING

QuoteQuote:
System key features  Image features
Zeiss Sonnar lens specific of cemented in f1.1 light flare is seen good contrast and high resolution power is obtained. flair's 70% f1.25. faded contrast increases flare at f1.4. F1.7-f2.8 on contrast resolution confocal, limits the times segregation in f4 will be further improved. Eye-opener is the uniformity of the image quality from the Centre in particular to the surrounding.
Decrease in the amount of ambient light in f1.1 at f1.7 67% 93%, is very good. Distortion aberration-DIST's +-0.3%. Is a parallel macro lens.
8 Faces in 5 faces and amazing as a bright lens-simple lens configuration and multicat "naked" produces high quality and beautiful coloring.

Use proper
ideal for telephoto effect also to accentuate themes such as flowers, portraits, pets, animals, blurred around the beauty and やわらかみ of large diameter lens and until f1.1-1.7.
You can use all applications in depth, the improvement of the image of rise in f2-4 things. suitable for landscape photography, snap the f5.6 to f8 with deep depth of 25 mm and 2 m, indoor outdoor according to Pinto, 4 m.
take, and expanded the subject equivalent to 135 mm telephoto lens, which 10 minutes from the subject in.

Cautions on use
It is not an autofocus lens. Do the focus firmly in the depth of the shallow f1.1-2.8.
Note that because loss of image quality starts by diffraction aperture f8 crosses.

SONNETAR 25mmF1.1 (Mount of PENTAX Q) instructions

 System specifications  Pentax Q-mount lenses
Configuration: use high refractive index glass, Zeiss Sonnar type 3 5 elements in 4 groups
Focal length: 25 mm
Opening f value:1.16
Field angle: 18 (full size 135 mm equivalent 35 mm)
Filter diameter: Φ 30.5P0.5 standards
Dimensions: diameter Φ 40mm長 depth: surface of Mount 24.5 mm
Weight: full set of 75 g
Aperture: Germany-made circular IRIS
Coverage: infinity's proximity allowed up to 50 inches
Product availability may take some time to delivery. Please note.
02-24-2012, 08:09 AM   #45
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Hereafter some specifications as put together and handwritten by Mr Miyazaki himself.

Source: http://www.mapcamera.com/html/ms_optical/zonnetar25.pdf

- 5 lenses in 4 groups ; 8 multi-coated surfaces
- 3 lenses made of glass with ultra-high refractive index
- apertures: f/1.1 to f/16
- diaphragm is "made in Germany" (12 rounded blades from the pictures)
- angle of view: 18 (equivalent to 135mm focal lens on 24x36)
- length: 24.5mm from lens mount (hood adds another 10.5mm)
- diameter: 40mm
- filter mount: 30.5mm diameter with 0.5mm pitch
- weight: 75g
- minimum focussing distance: 50cm (not inches!)
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