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Forum: Pentax News and Rumors
12-13-2022, 09:08 PM
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Forum: Post Your Photos!
06-12-2018, 11:43 PM
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Thanks Adam! It was definitely one of those magical moments.
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Forum: Post Your Photos!
01-27-2017, 04:13 PM
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Forum: Pentax K-1 & K-1 II
05-03-2016, 01:36 PM
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Came across this video and thought others may also be interested:
PENTAX K-1 Time Lapse Test
You Tube
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src="https://www.youtube.com/embed/zRXXQuRzTYU?controls=1" allowfullscreen>
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Forum: Pentax K-3 & K-3 II
03-18-2016, 12:15 PM
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repaap, great sunset shot through the trees with the moon above, I love that one!
Here are some photos from my commute by bike to work yesterday, on a beautiful sunny day :)
Mist in the Sun by C R, on Flickr
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Forum: Pentax Full Frame
03-18-2016, 02:20 PM
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Forum: Pentax Full Frame
03-18-2016, 09:34 PM
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I'm not sure where you got some of these ideas, and feel the need to assert them so strongly, when there doesn't seem to be any evidence for them. The technical explanation behind the normalization scaling performed by DxOMark to get the Print scores from the Screen scores quite clearly does not take viewing distance into account at all, it simply normalizes to a common output resolution (N_0 = 8 MP). Detailed computation of DxOMark Sensor normalization - DxOMark
Furthermore, while the normalization 'process' itself does not take into account sensor size directly in that step, that does NOT mean that the normalized or Print scores will not yield higher scores for larger sensors than smaller ones (of a common sensor tech/age). To see this, first consider the initial Screen scores which reflect the per-pixel noise levels. Per-pixel noise will be lower for larger pixels than for smaller ones of the same tech age. Now consider some examples of APS-C vs FF sensor combinations that we would like to compare.
1. 16 MP APS-C vs 16 MP FF
2. 24 MP APS-C vs 16 MP FF
3. 16 MP APS-C vs 36 MP FF
In case 1, the FF sensor will yield a higher Screen SNR score thanks to it's larger pixel pitch. Then the normalization step will treat both sensors equivalently, since they have the same number of pixels, and thus the normalized Print scores will show the same trend as seen with the Screen scores -- the FF will still be better.
In case 2, the FF will yield a relatively even higher Screen SNR score than the APS-C since it's pixels are even more relatively large compared to the 24 MP APS-C sensor. This time the normalization step will even the playing field a bit, however, as the larger number of pixels for the APS-C sensor will bring it's Print score more in line with the FF's Print score. (In fact the 24 MP APS-C Print score should be quite similar to the 16 MP APS-C score for the same sensor tech/age.)
In case 3, the FF will yield about the same Screen SNR score as the APS-C since they have about the same pixel size. However, this time the normalization step will reveal the big advantage of the larger sensor, as the much larger number of pixels will result in higher Print score for the FF than the APS-C.
So from these examples we can see why sensor size will lead to improved ie. reduced image noise when using an output image at the same size (the normalization step is required in order to do this comparison properly), as indicated by its higher Print score.
We can also see how (at least with current sensor tech -- it didn't used to strictly be the case) for a given sensor size, the number of pixels does not really matter for output image noise, as the effect of noiser per-pixel levels for a higher resolution sensor will be negated during the normalization step in which the higher resolution sensor has it's noise 'averaged out' and ends up with about the same Print score as the lower resolution sensor. So, the only down side to a higher resolution sensor is typically cost, and intermediate image file sizes, while the up side is higher resolution in some situations (at least at low ISO's).
These are general rules of thumb and of course if sensors have significantly different tech or are customized in significant ways relative to each other, performance may deviate somewhat from these guidelines.
I hope this is relatively clear and helpful. :)
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Forum: Pentax Full Frame
03-16-2016, 04:05 PM
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Forum: Pentax Forums Giveaways
01-31-2016, 10:54 PM
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This can be an odd but interesting effect to play with, if you want to highlight what a shot would look like when the focus point is switched between a near and farther subject.
Start by finding a composition that includes an interesting near subject and one that is further away, and then take a pair of photographs using a relatively shallow DoF -- one shot with the focus set to the nearer subject, and one with the focus set to the further subject. Then in your image editor of choice, mirror one of the images, and merge half of it with the opposite half of the second image, to achieve something like below. You may have to experiment with which parts of each image to mask out or smudge/heal along the boundary until you are happy with the result.
 Changing Focus by C R, on Flickr
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Forum: Monthly Photo Contests
12-31-2015, 05:36 PM
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Spotted these in an empty lot on my route to work.
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Forum: Pentax K-3 Photo Contest
04-30-2014, 12:30 PM
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Caught this image of a mime one year at the Vancouver Folk Music Festival on a glorious Summer day. Hope you enjoy it, too!
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Forum: Pentax K-3 & K-3 II
01-26-2014, 10:47 PM
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Forum: Pentax K-3 & K-3 II
01-17-2014, 10:32 PM
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Put together a new computer a year ago to replace my 7 or 8 year old single core machine, and been very happy with the upgrade :D
23'' ASUS ProArt IPS monitor which I love although larger would be nice (also two vertical 1024x1280 older monitors on the sides, useful for document reading, folder viewing, etc.)
8 core AMD 8350 4 GHz cpu
32GB DDR3 RAM
256GB Samsung 840 Pro SSD
Two 3TB HDs mirrored for media storage
AMD 7850 graphics card
Recently tested out the computer muscle when editing together a 4K timelapse of Angkor Wat sunrise from a visit there in November:
You Tube
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src="https://www.youtube.com/embed/snE9x7B3kfo?controls=1" allowfullscreen>
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Definitely helped to have the extra RAM and cpu power, although it didn't seem Photoshop (CS6 64-bit) was that well optimized to use all 32GB RAM as it usually started creating huge swap files on my SSD before getting anywhere close to using all the available RAM...and then it would crash when trying to load and align all the 700 images (again before using all the RAM). Had to load and align the images one by one in a batch instead, and for that you don't really need much RAM =/ So, I would say in my experience 32GB RAM is definitely overkill for photo work, though it is quite useful for video work.
P.S. If you watched the timelapse video above you may think it's pretty jerky in parts and surprised I did all that work aligning frames (and also de-flickering exposures!), but believe it or not it is MUCH better than the raw shots I started working with -- I didn't bring a proper tripod along and just had my K10D mounted on a mini-tripod a few inches off the ground...which was wet sand and so the camera would sink in slowly and needed adjustment to right it every once in a while. Some groups of shots were rotated by a LARGE amount relative to others =( I look forward to another sunrise timelapse attempt somewhere, with the improved metering on my new K3 and with my normal tripod!
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