BetterPhoto Q&A
Category: Digital Files and Formats

Photography Question 

Amanda M. Freese
 

Resizing Digital Photos?


Set up: when you download your newly shot photos onto your computer and then open them up in Photoshop, I go into Image size to resize for best resolution quality. My question is: What's the best way to resize Rebel XTI's digital files when going through this process? Is it necessary at all? The images are in a Raw format at this moment, and I had planned to do my edits and then saving as a JPEG. Is that part correct as well? Thanks!


To love this question, log in above
October 20, 2007

 

Richard Lynch
  Amanda,
I would not start working with an image by resizing it. Your images come off the camera with a pixel count (e.g., 3000x2000 or whatever) and that is the real resolution of the camera. The ppi (number of pixels per inch) is really an arbitrary thing - at 72 ppi, 300 ppi or 3000ppi, the image will have the same resolution in pixel count (as long as you don't resample). The ppi just defines how you expect it will be used.
I'd leave the ppi alone and make adjustments to the image (color correction, white and black point correction, dust fixes, small object removal, cropping, etc. see my Correct and Enhance Your Images course. Then worry about resolution at the end, after you know what the purpose of the image is and what output you will be using (these concerns are covered in my From Monitor to Print course, along with helping you iron out color management and calibration issues).
I would NOT save working versions of your image as JPEG for 2 reasons:
1) JPEG will not allow you to save Layered corrections (for the importance of layers, see my Leveraging Layers class).
2) JPEG will degrade in quality with multiple saves - even at highest quality. PSD formats and others like TIFF have compression without loss, while allowing you to save layered corrections.
Now that I've plugged almost every class I do here on BetterPhoto (;-) I hope I also actually answered the question!


To love this comment, log in above
October 21, 2007

 

Amanda M. Freese
  Oh you have, and I'm glad for the plugs, because I'm enrolling right now. Thanks so much!


To love this comment, log in above
October 21, 2007

 

Amanda M. Freese
  Actually, I had learned that from a mentor who instructed that resizing the photos (for a 5D camera to 9X6 & 400 pixels) would keep the highest quality up to what she imagined the largest print the client may ever need 11x14. She uses Pictage for the print package and album service, and I guess they also request you to send smaller size images. I have since stopped my mentoring as it seems I am getting a better edcucation from this site and the new classes I've just enrolled in.

BIG THANKS!


To love this comment, log in above
October 21, 2007

 

Amanda M. Freese
  So if I cram more ppi into a 550x550 size image it will be clearer?


To love this comment, log in above
October 22, 2007

 

Richard Lynch
  Amanda,
Sorry if my original answer was unclear. I am not sure, though, how you propose to 'cram' in more ppi to an image that is already defined by a pixel size.

You can't enhance detail if you don't already have it, neither by changing ppi or changing the number of pixels.

The number of pixels is a finite measure of detail. What you get off the camera is all the original detail you will ever get. You can upsize an image (called interpolation) or downsize it (decimation) and what happens in that process is that Photoshop/Elements has to guess at what should or should not be there...it isn't like you see on TV where they can make it seem like you can enhance detail to find more of it -- that is a hollywood trick, reverse engineered (they use an image with detail first and create the blurry or pixelated image and show them to you in reverse). Changing the ppi just tells the printer to use the pixels differently. The result may appear somewhat different, but not usually much clearer.

There is a 'best' resolution for output (it depends on what you are printing to, or displaying on). You can do things to make sharpness in your images more apparent (e.g., using sharpening techniques), but these have limitations. I cover these things in my classes. Often times you can print with way less than 400ppi and get great detail depending on the type of printer. Inkjets use pixels differently than offset printing (halftones), and that is different still than images on the web or printing transparencies (which can require more than 400ppi). You need to target resolution to the image use (I cover that in From Monitor to Print: Photoshop Color Workflow)

If you 'cram more ppi' into any image that has a set number of pixels, it will be SMALLER, not necessarily clearer.

OK?


To love this comment, log in above
October 23, 2007

 

Richard Lynch
  PS - glad you signed up for courses! Whether mine or from another instructor, you should enjoy and learn a lot.

Richard


To love this comment, log in above
October 23, 2007

 

Amanda M. Freese
  no your answers are clear, im in the learning mode so it hasn't jived yet. I'll be looking over your answer a couple of time to get it. . I wish our classes started sooner than Nov. 7th.. Im so eager to begin. . Thanks, I love BP!


To love this comment, log in above
October 23, 2007

 
This old forum is now archived. Use improved Forum here

Report this Thread