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09-07-2011, 12:42 AM   #1
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Question about the K-5 LCD magnification

... and not only.

How to put it?
When I magnify up to x32, how many CMOS pixels represent one pixel on the LCD ?
I suspect that, actually, the maximum magnification is actually more than 100%. If so, how much is 100%?

Then, how does that apply to older cameras like K-20?

Octav

09-07-2011, 01:12 AM - 1 Like   #2
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Your screen is 640 x 480. So in landscap a 7,7x magnification gives 1:1 (4928/640=7,7). When orientation is different, the magnification is different. When a portrait picture is taken 5,1 is 1:1 (3264/640=5,1).

Last edited by RonHendriks1966; 09-07-2011 at 06:48 AM.
09-07-2011, 02:17 AM   #3
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Thanks. That comes in concordance with my assumptions.
I always felt that a magnification of about x8 is close to 1:1.

So x32 is about 300% magnification.
09-07-2011, 02:44 AM   #4
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QuoteOriginally posted by RonHendriks1966 Quote
Your screen is 640 x 480. So in landscap a 7,7x magnification gives 1:1 (4927/640=7,7). When orientation is different, the magnification is different. When a portrait picture is taken 5,1 is 1:1 (3264/640=5,1).
Are you sure the screen is a VGA (640x480) ?
The screen have 921 000 pixels, 640x480 = 307 200pixels; they are 600 000pixels missing...
Or maybe it's 307 000px/color, RGB)

09-07-2011, 02:57 AM   #5
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QuoteOriginally posted by RonHendriks1966 Quote
Your screen is 640 x 480. So in landscap a 7,7x magnification gives 1:1 (4927/640=7,7). When orientation is different, the magnification is different. When a portrait picture is taken 5,1 is 1:1 (3264/640=5,1).
Hi
Please tell me where I am wrong here; I have always considered a 4times enlargement on my K-5 screen to be pretty exactly a 100% percent representation.
I have come to this conclusion this way:
When I import a file (a picture of a test chart) straight from the SD Card into my computer, open up this file in PhtoShop and view it at 100%, then put up this very file on the camera screen and enlarge it there until I get pretty well the same crop dimensions as displayed on the computer I always finish up at a 4x value on the cam. The test chart picture does allow for pretty good alignment comparison.

Greetings
09-07-2011, 05:05 AM   #6
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QuoteOriginally posted by Couscousdelight Quote
Are you sure the screen is a VGA (640x480) ?
The screen have 921 000 pixels, 640x480 = 307 200pixels; they are 600 000pixels missing...
Or maybe it's 307 000px/color, RGB)
you are correct, they of course count each R, G, and B dot in their 'pixel' count. Marketing folks like bigger numbers

QuoteOriginally posted by Schraubstock Quote
Hi
Please tell me where I am wrong here; I have always considered a 4times enlargement on my K-5 screen to be pretty exactly a 100% percent representation.
I have come to this conclusion this way:
When I import a file (a picture of a test chart) straight from the SD Card into my computer, open up this file in PhtoShop and view it at 100%, then put up this very file on the camera screen and enlarge it there until I get pretty well the same crop dimensions as displayed on the computer I always finish up at a 4x value on the cam. The test chart picture does allow for pretty good alignment comparison.
'100%' refers to where one pixel in the sensor corresponds exactly to one pixel on your screen (whichever screen you're looking at; camera or computer). Since your computer screen shows a larger number of pixels than your camera's small display, zooming the camera until it matches the same crop area as your computer screen doesn't put the camera screen at a 100% view.

for example, if your computer screen has a resolution of 1600x1200, then at a 100% view you can view an area of the image that is about 1600x1200 pixels. if you were to zoom to have the same area viewable on your camera's display, you would be looking at 1600x1200 pixels of the image, but on a 640x480 screen, so each pixel on your screen would actually be representing 2.5 pixels of your picture, and you would have to zoom in another 2.5x to get your camera to be at '100%'

Last edited by jerm1386; 09-07-2011 at 05:18 AM. Reason: responded to another person as well
09-07-2011, 06:32 AM   #7
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Hi
Thanks jerm1386, its it marvelous what you can see when you look and what you can figure out if you use your brain. But I plead extenuating circumstances, never went to school, got all my knowledge from bartenders

Greetings

Last edited by Schraubstock; 09-07-2011 at 06:41 AM.
09-07-2011, 06:51 AM   #8
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QuoteOriginally posted by octavmandru Quote
Then, how does that apply to older cameras like K-20?
K20D has an QVGA screen, so that is 320x240 pixels. That screen has les detail, since the pixels are bigger to fill the smaller screen.

09-07-2011, 06:54 AM   #9
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I don't do math well.....will someone just figure what magnification on the K5 equals near 100% on a 17' standard monitor?
Regards!
09-07-2011, 07:10 AM   #10
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QuoteOriginally posted by Rupert Quote
I don't do math well.....will someone just figure what magnification on the K5 equals near 100% on a 17' standard monitor?
Regards!
assuming a non-widescreen 17" monitor with a standard resolution of 1280x1024 and our camera's 4928-pixel wide image

at 100% view, approximately 1/4 of the width of the image (1280/4928) is displayed, so 4x magnification on your camera display will show about the same image area as 100% view on your screen
09-07-2011, 07:33 AM   #11
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QuoteOriginally posted by Rupert Quote
I don't do math well.....will someone just figure what magnification on the K5 equals near 100% on a 17' standard monitor?
Regards!
Define your standard monitor?

Graphic display resolutions - Wikipedia, the free encyclopedia

It would be nice to have in the next camera a FWVGA screen (845x480 pixels, so widescreen). Or even a little more resolution. Or maybe even qHD wich is also a 16:9 widescreen of 960 x 540 pixels (so that makes it 1.55 million dots).
09-08-2011, 01:32 PM   #12
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darn i thought i was good at math but this time i realize i was suck at math >.< . so the closest to 100% was 8x?
09-08-2011, 04:27 PM   #13
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+1

I got lost in all the maths too. So 8x on the camera's LCD screen = 100% crop on the computer screen?

Does this apply also to the K-7? The K-7 has 920K pixels. The K-5 has 921K.
09-08-2011, 09:41 PM   #14
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QuoteQuote:
+1

I got lost in all the maths too. So 8x on the camera's LCD screen = 100% crop on the computer screen?

Does this apply also to the K-7? The K-7 has 920K pixels. The K-5 has 921K.
i dont think that's the way it shows. 8x on the cameras will give you exactly 640x480 pixel of your picture fit onto the camera LCD. (sorry for my bad english) if you want to compare to computer screen u should consider the screen resolution too. cmiiw
09-08-2011, 10:26 PM   #15
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Surely the best way to determine what magnification is 1:1 is to look at the real thing and look at the live view and if they are about the same size then you've got 1:1

..... and isn't an LV magnification factor for 1:1 giong to change depending on the fiocal length of the lens attached?
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