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10-08-2011, 08:09 AM   #1
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File sizes?

I went out this morning and used my K-r for the first time. I noticed when I put a picture in photoshop, the size of the image is about 6X8, on a 10megapixel setting. The size from my K-100d set on 6 megapixel is about 33X44ish. Why are the files so small in 10 megapixel?
One other thing, I noticed if I hold down the shutter, it won't snap pictures one after another but I can't find a setting for multiple frames like the K-100 and IstD have. It did snap two in a row a couple of times when I wasn't shooting anything I wanted two shots of.
I do like the brightness of colors when I was out before the sun was actually up, set on night scene it took great pictures.

10-08-2011, 08:15 AM   #2
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print size is based on image resolution/dpi. To change the print size, just increase or decrease the dpi setting, this will have no real effect on the digital image, only on how it is handled when printing.

to get into drive mode, press the up button on the back of the camera, this will allow you to access the drive mode options. Select hi-speed burst mode to shoot at the full 6fps
10-08-2011, 12:44 PM   #3
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Yes, any DPI numbers you see are only meaningful when scanning or printing. They mean nothing when you are shooting and processing images; in essence, they're place-holders in the metadata. If you look at the EXIF metadata of a scanned image, the DPI is good to know. With photos that you shoot, only the frame size should concern you.

So with my K20D I could choose frames of 4672x3104 pixels (14.6 megapickles), or 3872x2592px (10mpx), or 3008x2000px (6mpx), or 1824x1216px (2mpx); or if I'm shooting fast (23fps) bursts, 1536x1024px (1.6mpx). Any of those frame sizes could be printed at any DPI rating from 1dpi (for BIG posters!) to 72dpi (web-display standard) to to 1000dpi (for small tight prints).

In other words: Don't sweat it.
_____________________________________

See your user manual about Drive Modes to select different ways of shooting. Have fun!
10-08-2011, 01:47 PM   #4
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ok that makes no sense

Using photoshop I take a photo set on 10mp from the K-r and crop it. When I check the size of the image, it goes from 6"X8" to 2"X3". With the photos I took with the k100d, set on 6 mp, the image goes from 33X44" to 10X15". I would think if I'm using four more megapixels, the file size would be larger. If I take a picture of a cat, and want to crop out the shovel and stack of buckets and two dogs fighting in the background, and still have a decent cat photo, I'd get a better one using the k 100d rather than the K-r, in this instance. I have no idea why if I set the k-r at 10 megapixels, the file is SMALLER and not LARGER. I never set anything on the k100. I went from a 4mp (which took a 22"X33") to 6mp and it INCREASED to something like 33"X44". So why is a 10mp setting taking a 6"X8" photo????? and if I already took the photo, I've lost the opportunity to get it bigger. What is it I have to change? I shouldn't have to do anything if it's set on 10mp. I can't see anything in the manual or on the camera menu about DPI. Gaaaahhh someone with a brain help me before tomorrow at 2pm please please Thanks!

10-08-2011, 01:49 PM   #5
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I got the burst photo thingy set, thank you very much! That was an easy fix. Now if I can figure out the dpi thing.
10-08-2011, 02:01 PM   #6
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the size you see (2x3) is the print size you get from the image you get from printing the image with the encoded dpi. Don't trust inches in photoshop, the size of the print is flexible and can easily be changed when you actually print it out. If you're determining file size through the print size, i can give you a 1000"x2000" from only 2 megapixels, printed at 1 dpi. More megapixels = more detail, no matter the what the dpi is. DPI stands for Dots Per Inch, which is how many pixels you're telling the computer to cram into a given space of paper when printing. Mathematically, you take your megapixel count and divide by the DPI to get the image size. If you decrease the DPI, the image size gets bigger, if you increase, then the image gets smaller. However, the changes in size are only for the final print and have no effect whatsoever on the actual image data. You can always change your DPI when you're ready to print to get a larger or smaller print.
10-08-2011, 03:30 PM   #7
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Ok, I make my own calendars. I make 11X17 sizes as well as the 8X11". I can use cropped photos *within reason* for either camera, and not lose any resolution. I'm thinking if I want a photo to show up on an 11X17" calendar, I would use something from a file that was 20X30 inches rather than 6X8". Does that make sense? So, if I crop something down out of the bigger file, I'm not losing much. If I'm starting with a 6X8" photo, I can't crop anything for use in a calendar that big. Why is the 6mp file larger in the "image size" than the 10 mp file? If I crop out something in the middle of the 6mp picture, it's way bigger than what I crop out of the 10mp file. The finished size on the 6mp is bigger than the 10mp which doesn't make sense to me since 10mp is LARGER than 6mp. Why does it do that?
I go to bull ridings, and if I take shots that have a lot of room around the edges, I can go home, crop down and have a decent photo still. If I have to zoom in on the action, I risk chopping off heads, hands, feet etc. but if I have the camera on 10mp, shoot and crop down to a third of the photo size, I'm only going to have a 2X3" file rather than the 10X15" I get with the 6mp files I take. Why is that?
10-08-2011, 03:45 PM   #8
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Here's an example.I took this photo set on 6 mp with the K-100d and it's a horizontal shot, and I cropped this out of the middle.


Flickr says the bull is an original size of 1100+ by some other big number. Then I do this cat that I took today, in photoshop the cat is a whopping 7X10 inches *sarcasm*, but when I put it in flickr it's 2200X3300 or something, even bigger than the bull. I'm not going to post the original cat since it's even bigger than the bull - but is the issue with photoshop? Since apparently in flickr the sizes are reflecting the megapixels. I saved the photoshop crop to a file, then sent that to my flickr account. Basically you're saying I should shoot to my heart's content at 10 megapixels and screw what photoshop is telling me?? The flickr information is making me feel better about all of this. I should stick to painting!

10-08-2011, 04:14 PM   #9
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flickr is telling you the actual resolution in pixels (dots), whereas photoshop is telling you the print size you'd get with that many pixels at whatever DPI setting the image is at. The reason why you get "bigger" files for your older camera is because by default, it is set to a lower dpi setting. remember the formula megapixel/dpi? photoshop is just showing you the result of that based on the dpi setting the image is currently assigned. If you were to reassign a different dpi value for the image, photoshop would show you a different image size as the result
10-08-2011, 04:28 PM   #10
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So how do I reassign the dpi value? The K100 must have automatically done that. I don't know why the k-r doesn't.
I notice the same thing when I use my p&s, larger megapixels but smaller in photoshop. Is it a camera thing? I can't find where to set that. The megapixels are set, and the quality is set. What else is there? Thanks.
10-08-2011, 04:45 PM   #11
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Again, don't worry about the DPI when you're editing an image. If you want, you can tell PS to use some specified resolution like 300dpi, and it will tell you what size can be printed at that resolution. Or you can tell it what size you want to print, and PS will tell you what the dpi level is. But that's just for output. What's important is the number of pixels in your image: 4288x2848px (12.4mpx) or 3936x2624px (10mpx) or whatever. At 12.4pmx, that's about 4800dpi!!

So if you blow up a 12.4mpx image to 12x8in, you still get 400dpi on the printed page. That's beyond photographic quality, where the cutoff is maybe a little under 300dpi. Print that image at 18x12in, matte and glass and frame it, view it from 20in, and it's indistinguishable from a high-density chemical photo.

Last edited by RioRico; 10-08-2011 at 04:57 PM.
10-08-2011, 09:44 PM   #12
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Ok, I just want to be clear, when I am cropping an image that photoshop says is only say, an 8X10 and if I take the middle of it out, that reduces it down quite a bit, and I want the image to be at least 10X15, say. I can't get 10X15 out of an 8X10. What is it that I need to change, I can't find any type of setting in photoshop that will make the image bigger, or should I just change the image size to reflect a larger size to begin with? I guess I don't understand why this very large image is being perceived as something much smaller. Either it's a big file or it isn't, and for some reason these big pictures are being "read" as smaller ones. I have no idea what it is I need to change. Like I said, there isn't a dpi setting on the camera that I can find. I'm wondering why one camera would translate a 6mp file into something that is 33X44 and the next camera says a 10mp file is only 8X10. You're saying the photoshop program is reading it that way, I just don't understand why. I feel better knowing that the pictures I am taking aren't itty bitty. The K-r isn't the only camera that does this, like I said my kodak p&s does the same thing. For me, the important thing is that when I go to crop out all of the stuff I don't want in the picture, I still have a good-sized image to work with.
I'm not understanding why one camera will have larger image sizes with less megapixels. Am I making any sense? I don't ever print out my photos other than to either make 4X6's or print out for reference material for paintings. And calendar images. I end up cropping alot, like I said I learned to back off on the zoom at the bull ridings because I was cutting off body parts. Then when I get home I can crop out 2/3 of the image, and still have a workable photo in case I do want to make prints or calendars.
10-09-2011, 01:26 AM   #13
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Your camera just sets a predefined DPI that can be totally ignored.

I'm not familiar with PS, but a program like Irfanview allows you to print as you want. E.g. print original size (size = pixels / dpi), fit to page (dpi = pixels / size).

A quick search found
which shows how to change dpi in photoshop. I don't know if it applies to your version.
10-09-2011, 01:58 AM   #14
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As said above, DPI means nothing unless printing or scanning, and it can be overridden printing. Think the following URL is worth a minute or two of your time.

All About Digital Photos - The Myth of DPI
10-09-2011, 02:49 AM   #15
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QuoteOriginally posted by pamzpix Quote
Ok, I just want to be clear, when I am cropping an image that photoshop says is only say, an 8X10 and if I take the middle of it out, that reduces it down quite a bit, and I want the image to be at least 10X15, say. I can't get 10X15 out of an 8X10. What is it that I need to change, I can't find any type of setting in photoshop that will make the image bigger, or should I just change the image size to reflect a larger size to begin with? I guess I don't understand why this very large image is being perceived as something much smaller. Either it's a big file or it isn't, and for some reason these big pictures are being "read" as smaller ones. I have no idea what it is I need to change. Like I said, there isn't a dpi setting on the camera that I can find.

I'm wondering why one camera would translate a 6mp file into something that is 33X44 and the next camera says a 10mp file is only 8X10. You're saying the photoshop program is reading it that way, I just don't understand why. I feel better knowing that the pictures I am taking aren't itty bitty. The K-r isn't the only camera that does this, like I said my kodak p&s does the same thing. For me, the important thing is that when I go to crop out all of the stuff I don't want in the picture, I still have a good-sized image to work with.
I'm not understanding why one camera will have larger image sizes with less megapixels. Am I making any sense? I don't ever print out my photos other than to either make 4X6's or print out for reference material for paintings. And calendar images. I end up cropping alot, like I said I learned to back off on the zoom at the bull ridings because I was cutting off body parts. Then when I get home I can crop out 2/3 of the image, and still have a workable photo in case I do want to make prints or calendars.

You're confusing terminology is all.

DPI - Dots per Inch refers to printing - how many droplets of ink per sq inch. For example you want to print @ 250 DPI this isn't determined by the camera it's a measurement used for printing and can be assigned in any photoshop type program. All you do is to change the DPI setting in your image re-size box.

PPI - Pixels per Inch is the resolution and what you see on your monitor also a way to refer to the recorded pixels of the photograph. An example is your HD TV it can come in 720 or 1080 which is 720 PPI or 1080 PPI.

The Kr records/takes pictures at 12mp, 10mp, 6mp, or 2mp the setting can be changed on the first menu screen.

If the Kr is set up to record a 12 mp (megapixel) image it records it at 4288 x 2848 pixels (which is said to be a 1 x 5 crop) Multiplying 4288 x 2848 = 12,212,222.4 pixels (total size) or 12.2 megapixels or 12 megapixels (rounded down).

If you wanted to print a photo at 300 DPI (dots per inch) the largest you could print and maintain 300 DPI would be 14.29" X 9.49" (4288/300 X 2848/300). If you printed it at 200 DPI the largest size would be 21.4" X 14.2" (4288/200 X 2848/200). Remember these are print measurements the camera doesn't record in DPI it records in megapixels/pixels. There is a setting that you can change in photoshop. In Elements 9 it's located under EDIT>PREFERENCES>UNITS & RULERS> in the box titled New Document Preset Resolutions. I'm sure it's similar in any version of Adobe. Set your print resolution to what ever is acceptable. What this does is convert the PPI from the camera to the print setting (DPI) you select and it will be cropped using your assigned DPI settings. I suggest you go no lower than 200 or 250 and no higher than 300.

The reason for the size/print difference (one camera to another) is that the camera is transferring the file and the program is receiving the file at a lower PPI probably 72 or 96 PPI. These are OK settings to see the photo on the monitor and they do look huge but if you were to print them at those settings you'd see the huge difference and it wouldn't be a pleasant one.
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