Image re/sizes?

[IanB]

In the old days of digital photography [about 4 or 5 years ago ]; we were told that we should always work on a PS image at the size it will be printed>>30 x 40" photo should be 30 x 40" x 300 dpi in PS= lots of MBs

Is this still the case now we are getting far better; and larger original images off the camera? Like 78 x 52" x 72 dpi

I export from LR into CS3 and the image can be up to 23 x 15" at 240 dpi. Does the image really need resizing in PS before reworking, or is it just as good to resize with exporting from LR to be printed as a 300 DPI jpeg?

Just a note; I usually use the midsize raw which is 53 x 35" x 72 dpi

[Inspired]

I am so glad you asked that, i was wondering the same thing just yesterday!

[IanB]

I am so glad you asked that, i was wondering the same thing just yesterday!

Well no one wants to talk about image sizes Nicole; so do you get up to Kalbarri and the Murchison George very often? Now that's a beautiful spot for photography; I would love to get back there someday for another look.

How about those trees across the Greenough flats; they are unbelievable. I used to drive roadtrians through there.

[ricktas]

I still work on the largest possible image size I can. The only thing I do before that is crop, if needed. Reason being, what's the point of editing part of your photo that you are going to crop off at the end anyway. Mine are imported at 300 ppi, always. Only when I resize for web do I chop them down to about 100ppi, basing that on the fact most screens these days are closer to 100ppi than the old standard of 72

[Helen S]

Interesting, Ian. Since heading the way of RAW, all my images are opened at 300ppi in ACR (you can change this to whatever you want in Workflow Options, even upsizing the original image). I then do all my post processing work leaving sharpening until last. In other words, if I have to up res a file, I'll sharpen after I've done that and generally with the file viewed at 50%.

Now, this may not be the correct way of doing things, but it works well for me. I sure don't have any problems with the prints (up to 40" on the long side) that come back from the Photo Lab and have never received any complaints from customers in this regard.

[gcflora]

You all do know that if you open a file in ACR at, say, 100ppi and again at 300ppi (for example) that both opened images will have the same amount of pixels, don't you?

[bartt_06]

You all do know that if you open a file in ACR at, say, 100ppi and again at 300ppi (for example) that both opened images will have the same amount of pixels, don't you?

so what changes is the size of the physical image? the 300ppi being smaller? but therefore higher resolution? is that right? ...this topic is where i start to lose it!!

[gcflora]

so what changes is the size of the physical image? the 300ppi being smaller? but therefore higher resolution? is that right? ...this topic is where i start to lose it!!

Nothing changes at that point. What you're suggesting when you convert the RAW at 200ppi or 300ppi or whatever is that "I am expecting that I will be wanting to print this at 300ppi" and PS uses that to calculate the physical dimensions (cm/inches) that the number of pixels in your image can do at your chosen PPI. This way you can resize later by using cm/inches as the units rather than pixels. It's more of a convenience thing really.