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04-14-2020, 01:22 AM   #16
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I do not see much problems with any lenses capable of drawing that "large" image circle. I usually stop them down to f/8 or f/11 anyway in such situation. Even my old EM Ennalyt 35mm f/3.5 works but it has rather wonky field of sharpness and needs focus stacking to get corners "sharp" with other image content.

Of all lenses I used this way, I would rate Penron 15-30/2.8 the best in IQ considering those extreme positions.

But for pixel shift there is a slight issue. In extreme positions it seems that the sensor is unable to move in all directions required to make the pixel-shift composite. I regularly get grid artifacts when using pixel shift after the sensor has been moved to extreme corner. Sometimes it seems to work, but not nearly always even when the light is stable and does not change. I noticed this with MK1 model and it has happened with MK2 as well.


Last edited by MJKoski; 04-14-2020 at 01:29 AM.
04-14-2020, 06:52 AM   #17
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I have used this sensor shift + stitch method a few times. There is a gain of perceived image quality , 36Mp => ~ 45Mpixels. After 4 shifts, the equivalent sensor area is roughly 15% larger, it's not that much. In terms of overall image sharpness, what is gained in the center area of the image in lost at the edges, simply because lens sharpness drops rapidly at the edges. See how most lens MTF charts look: slow decrease of sharpness from center to edges at 20mm from center, usually something like -15% to -25%, then sharp decrease to -30%, -50% between 20mm and 25mm. Stitching two frames vertically shifted from min to max produces a 4:3 image aspect ratio, with slightly more resolution, and the stitching is easy since there is no projection and no mismatch of lens distortion from frame to frame. Anyone can do the shift manually, although not as quick as if it was done by firmware.

---------- Post added 14-04-20 at 15:57 ----------

QuoteOriginally posted by MJKoski Quote
But for pixel shift there is a slight issue. In extreme positions it seems that the sensor is unable to move in all directions required to make the pixel-shift composite.
Really. I've done 4 shifts + pixel shift, and it worked without PS artifacts. The sensor manual shift is a coarse shift, not one pixel at a time, there is still room for pixel shift even when the sensor is shift at each of the 4 corners.

---------- Post added 14-04-20 at 16:01 ----------

Unfortunately, pixel shift, or sensor shift modes don't remove lens CA, which even after correction is the number one limitation to image enlargement in prints. Sensor resolution and noise are not a problem. It's the CA that shows distracting first. On the 15-30, uncorrected CA can be as much as two pixels wide.
04-14-2020, 12:52 PM - 1 Like   #18
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Yes really. My first K-1 MK1 even made a silent clicking noise when sensor was first pushed to far left and top corner and pixel shift exposure started. Completely silent in the center position. This very same body also froze to max top shift position in super cold temps and required pulling out the battery to reset.
04-15-2020, 07:04 AM   #19
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QuoteOriginally posted by MJKoski Quote
Yes really. My first K-1 MK1 even made a silent clicking noise when sensor was first pushed to far left and top corner and pixel shift exposure started. Completely silent in the center position. This very same body also froze to max top shift position in super cold temps and required pulling out the battery to reset.
I haven't seen any issue on both my K1 and K1II. So far, my limits on print quality are: lens aberrations (if not well corrected), diffraction and lens corner sharpness. On a comparison of the same landscape shots in good light, everything being equal (FL 31mm, ISO100, shutter 1/500th and 1/800th) except lens aperture (f8 vs f10), what I find is f10 diffraction is already clearly visible compared to f8, side by side comparison (3 exposures at f8 compared to 3 exposures at f10). Diffraction limits already. So , really the only way I can see of getting finer details is to expose at f5 and stack three images to more clearly defined pixels.

04-29-2020, 07:47 PM   #20
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Update of firmware......not unreasonable when you consider the 645d came out with 9 firmware updates and the last was 2016
Maybe hire Fuji for post support....their cameras come out with updates more times than you can count
04-30-2020, 05:29 AM - 1 Like   #21
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Gosh lockdown is boring

QuoteOriginally posted by MJKoski Quote
Yes really. My first K-1 MK1 even made a silent clicking noise when sensor was first pushed to far left and top corner ...
Huh? A “silent clicking noise”? Your hearing must be better than mine!
04-30-2020, 06:49 AM   #22
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Mechanical noise. Something was driven "against the wall".
05-12-2020, 01:01 PM   #23
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Just updated my K1ii to 1.04 version, supposed to help with certain lenses and improve overall performance.

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