Question about the K-5 LCD magnification

octavmandru · 09-07-2011, 12:42 AM

... 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

RonHendriks1966 · 09-07-2011, 01:12 AM - **1 Like**

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).

octavmandru · 09-07-2011, 02:17 AM

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.

Couscousdelight · 09-07-2011, 02:44 AM

Originally posted by RonHendriks1966

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)

**Schraubstock** · 09-07-2011, 02:57 AM

Originally posted by RonHendriks1966

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

**jerm1386** · 09-07-2011, 05:05 AM

Originally posted by Couscousdelight

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

Originally posted by Schraubstock

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%'

**Schraubstock** · 09-07-2011, 06:32 AM

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.

RonHendriks1966 · 09-07-2011, 06:51 AM

Originally posted by octavmandru

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.

Rupert · 09-07-2011, 06:54 AM

I don't do math well.....will someone just figure what magnification on the K5 equals near 100% on a 17' standard monitor?
Regards!

**jerm1386** · 09-07-2011, 07:10 AM

Originally posted by Rupert

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

RonHendriks1966 · 09-07-2011, 07:33 AM

Originally posted by Rupert

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).

derico3 · 09-08-2011, 01:32 PM

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?

raider · 09-08-2011, 04:27 PM

+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.

derico3 · 09-08-2011, 09:41 PM

Quote:

+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

Smeggypants · 09-08-2011, 10:26 PM

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?

09-07-2011, 12:42 AM	#1
octavmandru Veteran Member Join Date: Jan 2009 Location: somewhere around Posts: 615	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
RonHendriks1966 Banned Join Date: Jan 2009 Photos: Gallery Posts: 9,675	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, 05:05 AM	#6
jerm1386 Site Supporter Join Date: Aug 2011 Location: Baltimore, MD Photos: Albums Posts: 45	Originally posted by Couscousdelight 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 Originally posted by Schraubstock 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

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09-07-2011, 02:17 AM	#3
octavmandru Veteran Member Join Date: Jan 2009 Location: somewhere around Posts: 615 Original Poster	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
Couscousdelight Veteran Member Join Date: Dec 2010 Location: Frog-eaters country Photos: Gallery Posts: 357	Originally posted by RonHendriks1966 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
Schraubstock Site Supporter Join Date: Oct 2010 Location: Melbourne Photos: Gallery Posts: 3,386	Originally posted by RonHendriks1966 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, 06:32 AM	#7
Schraubstock Site Supporter Join Date: Oct 2010 Location: Melbourne Photos: Gallery Posts: 3,386	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
RonHendriks1966 Banned Join Date: Jan 2009 Photos: Gallery Posts: 9,675	Originally posted by octavmandru 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
Rupert Veteran Member Join Date: Sep 2006 Location: Texas Photos: Gallery \| Albums Posts: 25,123	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
jerm1386 Site Supporter Join Date: Aug 2011 Location: Baltimore, MD Photos: Albums Posts: 45	Originally posted by Rupert 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
RonHendriks1966 Banned Join Date: Jan 2009 Photos: Gallery Posts: 9,675	Originally posted by Rupert 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
derico3 New Member Join Date: Jun 2011 Location: jakarta Posts: 9	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
raider Veteran Member Join Date: Jul 2007 Location: Perth, Australia Photos: Gallery Posts: 1,989	+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
derico3 New Member Join Date: Jun 2011 Location: jakarta Posts: 9	Quote: +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
Smeggypants Veteran Member Join Date: Sep 2010 Posts: 1,536	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?