Photo Printing Questions - Help

Joined: 25 Oct 2006 Posts: 36 Location: IRVINE, CA

Hello guys,

I have been into photography for about a year now and I am enjoying my Nikon D50 very much along with the 18-55mm kit lens and the 50mm 1.8 prime lens. I also enjoy the post process with Adobe Photoshop CS2.

But now - I want to make some prints! However, I am very clueless as far as the process goes how to optimize the best quality prints as possible. First and foremost I am thinking about making a photo book or something of that sort for a bunch of 4 x 6 images and was wondering what your takes were on GLOSSY versus MATTE photo paper. What is better and why?

Just to let you guys know - I am now shooting in RAW and was wondering how I should setup the resolution (image size) before I go to my local printing shop (COSTCO). Should I keep the maximum resolution before I take in my files to the store? What am i supposed to do exactly. I was wondering what the step-by-step procedure is for high quality printing.
As far as I know, my RAW images are in the extension .NEF. When I open that RAW file up to post-process in Adobe CS2, I have the option to use either ADOBE RGB, COLORMATCH RGB, PROPHOTO RGB, or sRGB IEC61966-1. I assume that the sRGB is the best one, but was wondering what you guys thought on that. Also, I will set the workflow to 16 bits, and use a Resolution of 240 pixels/inch.

My Nikon D50 does a size of 3008 by 2000 which is 6 megapixels. Are these settings the ones I should keep? Also - when i am saving from RAW, should i save as JPEG or TIF when I take these files for print? I assume that I should keep the same image size (as large as possible).

So yeah, I am thinking about also printing large. How large can I go reallly? Can I go as far as 8x10? How about 20x30 ? or is that too much?
Finally, should I bring JPEG files or TIF files or NEF files to the photo lab?

Thank you all so much in advance, this is my first time making a print!

Thanks,
Brian

Posted: Fri Aug 24, 2007 9:44 am

Brian,

All good questions. Let me see if I can help because the answers are not always obvious (I used to things differently than I do now). I recently attended my local PPA meeting where the presentation was on photo labs. They had 5 reps from the 5 most used photo labs from my area and we had a Q&A session with them. In the end here is what they use to print... jpg format (Some even said only use a quality setting of 10), sRGB color space (one lab used Adobe 1998 color space or sRGB) and a preference of at least 300DPI for the image size you are planning on printing. Most also said if you can not get the 300 DPI at the size you wanted then to let them up-rez the file, but those all were pro labs so if you are going to Costco you will want to up-rez it yourself because they will not. Also, I have printed from 240 DPI and been just fine.

So some other useful info you may not be aware of when prepping your images for all this...

Go to the 'Image' pulldown menu in the banner and select 'Image size...'

This will bring up a user interface window that will display important information about your image size, resolution, etc. The absolute most important check box you need to pay attention to first is the one in the lower left called "Resample Image". The difference between this being checked or not is huge so pay attention. Any changes you make in the Document Size area of the window will NOT degrade your image in any way as long as the Resample Image box is NOT checked. Because it is not checked when you change one item all others will change accordingly. For example lets say the resolution is 240 pixels/inch on an image that is 3000x2000. The Width should show about 12.5 (3000/240) and the Height should show about 8.33 (2000/240). Now with the Resample Image box OFF change the resolution to 300 pixels/inch and you should see the Width x Height change to 10 x 6.66. Now try changing the resolution to 72 pixels/inch and you get something like 41.67 x 27.78.

It is important to note that your Pixel Dimensions up top does not change. The image still has exactly the same number of pixels as when you started. By doing this you are not changing the actual data that makes up the image you are simply seeing how physically big the image would be if you 'squished' the pixels closer together or pull them further apart.

OK, why this is important. When you have an end size print in mind you can go to this menu, make sure Resample Image is OFF and simply plug in your desired Width or Height. If you want a 5X7 and the shot is portrait orientation then plug in 5 for the width or 7 for the height and you will see what the resolution will be based on that physical size. Also note that depending on the size you desire the actual aspect ratios might not match your native image aspect ratio. So for example when we plug in 5 for width on a 2000 x 3000 pixel image the height will come up as something like 7.5 and the resolution will be around 400 pixels/inch, and if we plug in 7 for the height the width comes up around 4.6 and the resolution around 428.57. To get an exact ratio you will need to crop the image with the crop tool set to the ratio you want.

OK, so one thing to watch for is if you plug in your desired Width or Height and the resolution starts to fall below the 240-300 pixels/inch range that is when you will need to up-rez the image. There are many ways to do this both in Photoshop and with third party software. In Photoshop this is where the Resample Image box comes into play. Now when you check this box anything you do with the dimensions and/or resolution WILL change your native image data. To up-rez it will have to 'invent' pixels to fill in areas. So if we set the Width/Height to 20x30 without the Resample Image box selected we see the resolution to be 100 pixels/inch/ Too low for printing the 20x30. So we select the Resample Image box and change the Resolution to 300. The Width/Height stays at 20x30 but notice the Pixel Dimensions change up top to 6000 x 9000. The tool had to invent 4000 pixels in the width and 6000 pixels in the height. So you can see where doing this too much can start to degrade the image, and there are better ways to do this, even in Photoshop. But we won't get into that here.

As far as how large can you go.... it depends. It depends a lot on the data in the image... what the image is. For example, lets say I have a picture of a black bear in a dark cave at midnight (A solid black image) and I blow it up to 40 x 60 from a 4x6 at 72DPI.. it will look amazingly good, just like the original, all black. It's not too hard for the tool to invent more all black pixels when that's all there is and all there is supposed to be. But try that same range of enlargement on an image with a lot of fine detail and you might run into trouble. One thing to remember is that typically larger images are viewed from furhter away and therefore can be a little more 'pixelated' than smaller prints and still look fine.

OK, last issue... 8 bit vs 16 bit. For printing I only take 8 bit images to the lab. The lab reps told us that the printers can not print 16 bit so they convert any 16 bit files to 8 bit anyway. I do work with 16 bit files up to a point. I do any edits that have anything to do with the tones in the image at 16 bit, then I convert to 8 bit and do the rest. Of course I always shoot in and keep the RAW files so I can go back to the originals if need be.

Posted: Sun Oct 14, 2007 11:43 pm

Dermit, thanks for the detailed explanation on this as it is very helpful info. I had bookmarked this page awhile back but not really read it. I just had to refer to it and it came in handy. Thx
==Judy