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 05/02/2013 02:32:57 PM · #1
I've got a Canon 7d. I'm wanting to blow some pictures up, poster size, and when I do, they turn out to be nothing but pixels. I thought with 18.1 megapixels that I'd be able to get larger pictures. Am I doing something wrong? Or worse yet, does my question make no sense?
 05/02/2013 02:38:38 PM · #2
If you go big in one giant step, you will get all sorts of ugly. You need to do it in small little steps. there are as many ways to do this as there are branches of faith, and each one will tell you it is the best. Google upsizing a photograph and you can see the options. Scott Kelby's is fine, but so are many others.

Here is the old post I based my thinking on. It is from 2004, so probably dead wrong now, but old habits die hard. The logic is that by taking a 10% increase each step, new pixels are decent approximations of the surrounding information, while if you do a 300% increase in one step you get less interpretation and more solid field color chunky pixelation.

PS be sure to work up in a lossless format. If you are working in JPEG no matter how good your plan, 20 saves will result in a chunky image.

Message edited by author 2013-05-02 14:56:37.
 05/02/2013 03:07:19 PM · #3
I tried Scott Kelby's method. Haven't printed the poster size yet, but upsizing in photoshop using his tutorial seems hopeful.
 05/02/2013 03:11:20 PM · #4
What are the actual dimensions (in pixels) of your original 18MP image, and what is the final size (in inches) of the poster you want to make?

Something sounds odd in your workflow -- you may be upsampling when you needn't ...
 05/02/2013 03:29:47 PM · #5
agree with generale, 18.1MP should be good for billboard size without upsampling; have you maybe set your camera to jpeg small instead of the highest resolution?
 05/02/2013 03:39:19 PM · #6
Originally posted by h2:
agree with generale, 18.1MP should be good for billboard size without upsampling; have you maybe set your camera to jpeg small instead of the highest resolution?


+1

I've printed poster size from the 8 mp rebel I used to use without upsizing.
 05/02/2013 04:08:07 PM · #7
Camera is set to the largest jpg.
 05/02/2013 04:09:12 PM · #8
stand back away from the wall more.
 05/02/2013 04:27:11 PM · #9
And while it has nothing to do with your question, can we lure you into shooting in RAW instead of large JPG? Once you get used to it you really will like it better.

And Mike's point is quite real, posters are not meant to be seen at the same distance as a 4x6. Expecting them to work from a couple of inches away is asking too much.
 05/03/2013 09:05:53 AM · #10
Originally posted by BrennanOB:
And while it has nothing to do with your question, can we lure you into shooting in RAW instead of large JPG? Once you get used to it you really will like it better.

And Mike's point is quite real, posters are not meant to be seen at the same distance as a 4x6. Expecting them to work from a couple of inches away is asking too much.


I'd shoot RAW but the post-processing kind of confuses me at times. What's the best program for working with RAW images? Guess I should buck up and do it anyway. And the advice to move back...pretty good. Never thought of that!
 05/03/2013 09:15:43 AM · #11
You need to verify your file is being saved at a minimum of 240 dpi or 300 and not 72dpi that's a very common problem for enlargements. Don't use save for Web, use .file save as
 05/03/2013 09:24:41 AM · #12
Originally posted by Damon:
You need to verify your file is being saved at a minimum of 240 dpi or 300 and not 72dpi that's a very common problem for enlargements. Don't use save for Web, use .file save as


I don't save for web...always "save as" but I don't see an option that allows for determining dpi. When I have the option, I save as a large file. Perhaps that makes a difference?
 05/03/2013 09:28:50 AM · #13
You can verify by going to edit and select image size. It will show the size and dpi. You also need to verify if you are opening the file from camera raw or LR that those settings are exporting the image to PS at full size. Just a couple of ideas.
05/03/2013 10:05:06 AM · #14
Originally posted by PuppyDogMom:


I don't save for web...always "save as" but I don't see an option that allows for determining dpi. When I have the option, I save as a large file. Perhaps that makes a difference?


You won't. The dpi is already determined by the image properties. Open the Image Size dialog, uncheck "resample" and change the dpi. You'll see that the physical size of the image changes, but not the pixel dimensions. So, for example, if you have an image that's 4800px on the long side, sized to 24" on the long side, you are *by definition* at 4800px/24in = 200px/in, that is, 200dpi.
05/03/2013 09:48:38 PM · #15
Originally posted by kirbic:


You won't. The dpi is already determined by the image properties. Open the Image Size dialog, uncheck "resample" and change the dpi.


Kirbic correct me if Im wrong but I thought dpi is what sets the image size, meaning the smaller or less dpi you have the larger the image can be and the more or greater dpi the smaller the image in relation to print size. I know the labs that I send my images to want at least 240 to 300 dpi to print a quality 8x10, so if you start with an image that is 2400 x 3600 at 300 dpi which is large enough to print a 8x12" print, then you change the dpi to say 100, the image size can technically go up 24x36" but with larger pixels. So its not the image size that distinguishes dpi but the other way around. I know it sounds like the same but everything else is controlled by the dpi.
 05/03/2013 09:51:49 PM · #16
Originally posted by Damon:
Originally posted by kirbic:


You won't. The dpi is already determined by the image properties. Open the Image Size dialog, uncheck "resample" and change the dpi.


Kirbic correct me if Im wrong but I thought dpi is what sets the image size, meaning the smaller or less dpi you have the larger the image can be and the more or greater dpi the smaller the image in relation to print size. I know the labs that I send my images to want at least 240 to 300 dpi to print a quality 8x10, so if you start with an image that is 2400 x 3600 at 300 dpi which is large enough to print a 8x12" print, then you change the dpi to say 100, the image size can technically go up 24x36" but with larger pixels. So its not the image size that distinguishes dpi but the other way around. I know it sounds like the same but everything else is controlled by the dpi.


It is the same, one defines the other. For an image of a given pixel size, if you set the dpi, that will determine the size it prints. If you set the print size, that determines the dpi. Either way.
 05/04/2013 03:08:57 AM · #17
Can you show us one of those files? The problem has to be the way your camera captures the image or how you save it after the editing. I printed very big stuff from my D80 (10mpx.) in the past and I've had no problems, so your camera should allow VERY big prints :)
 05/04/2013 06:33:40 AM · #18


This is a photo that I tried to print (13x19).
 05/04/2013 09:37:23 AM · #19
Originally posted by PuppyDogMom:


This is a photo that I tried to print (13x19).

72 dpi x 72 dpi

You will want that to be at least 300 dpi from the camera. (I use 350 dpi.)

Somewhere in the export from camera or import to PP application, you are converting to a "Internet display" resolution. You'll want to figure that out. Or, it could be your export from your PP app. Check all those preferences for the resolution settings.

Yes, a 300 ppi image at 13"x19" will be probably 30 to 40 MB in file size. (The full size image you uploaded is 2336x3192 px and 1.6 MB in file size, but 72 dpi x 72 dpi.)

Message edited by author 2013-05-04 10:51:11.
 05/04/2013 09:55:23 AM · #20
Originally posted by PuppyDogMom:
...
I'd shoot RAW but the post-processing kind of confuses me at times. What's the best program for working with RAW images? Guess I should buck up and do it anyway. And the advice to move back...pretty good. Never thought of that!

Your camera in RAW image capture mode records all the image data the sensor can detect. This is often more than can be displayed by the LCD monitor. There may be dynamic range of light available to you that can be utilized, for example.

When you capture images in JPG (Large/Fine), your camera's processor discards as much as 90% of the image data. So, in postprocessing, your flexibility to enhance an image is limited. And, sometimes camera processing algorithms make parameter choices you wouldn't necessarily make. It's perfectly okay to shoot in JPG capture mode. Some results may be spectacular. But, I'd recommend exploring the potential of RAW image capture.

On my Mac systems, I use Apple's Aperture v3.4.4. If you are a PC person, then Lightroom is your RAW processing pathway.
 05/04/2013 12:20:38 PM · #21
72 dpi, 300dpi ... resolution is irrelevant until you get to printing the image. Remember that this abbreviation stands for "dots per inch" -- relating only to print size, and has nothing to do with the total file size, in either pixels or bytes on disk (the latter being dependent on type and degree of file compression used, and image characteristics).

The only thing which is relevant in your situation is the total number of pixels captured. For a 13" x 19" image you need:

1300px x 1900px @ 100dpi
2600px x 3800px @ 200dpi
2900px x 5700px @ 300dpi

You can take exactly the same file and print it at different sizes by changing the resolution without changing the number of pixels. For example, a picture which is 300 x 300 pixels will print as a 1" square at 300dpi, a 2" square at 150dpi, a 3" square at 100dpi, and a little bigger than a 4" square at 72dpi.

My suggestion would be to open the image size dialog for the original image, uncheck the "resample" option, and change the physical dimension to what you want; the resolution will change but the total number of pixels will not. As long as the resolution remains above 150dpi your print should look fine.

Perhaps these tutorials will explain more fully/clearly:

Resizing Pictures to Standard Print Sizes

DPC Prints Tutorial
 05/04/2013 02:57:47 PM · #22
Originally posted by hahn23:
[quote=PuppyDogMom]...
What's the best program for working with RAW images? /quote]

On my Mac systems, I use Apple's Aperture v3.4.4. If you are a PC person, then Lightroom is your RAW processing pathway.


Respectfully, I'd like to disagree. I've started to use Capture One Pro, and it's pretty much mind blowing.
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