Should a photograph be reduced in steps or all at once?

[fotobill]

I've heard that when making a photograph smaller in Photoshop the results are better if it's done in steps instead of all at once.

If this is true how much should it be reduced each time and should the change in pixels per inch be done before reducing the image

My camera saves at 300 ppi at 3872 pixels wide (sometimes they are cropped which makes them smaller) and for the web I need about 500 pixels wide at 72 ppi.

 

[BlueFlare]

If you have Photoshop 7 or older, resize with steps of 50%. This means you can resize a few times with 50%, but also values like 25% or 12.5% are allowed. If you have Photoshop CS or later, select bicubic sharper as your interpolation method if you downsize (or bicubic if the result is too sharp) or bicubic smoother if you upsize.?

 

[fotobill]

Thanks, I have version 7 and will do as you suggest.

Bill

 

[MindBender]

If this is for a print... the first thing to try is tweaking the DPI. You can often squeeze out a good print at a larger size by sacrificing DPI a little bit...

Resizing down... usually doesn't matter.
Resizing up... sometimes it's best to work with very small incriments... 10% or less depending on the image. What it's doing is, basically, applying a slight unsharp each time it scales the image. So by scaling in smaller steps... you sharpen each slightly interpolated image and therefor don't make PS work as hard in each step and maintain some of the clarity of the image even though it's guessing about the pixel locations. Doesn't work for all images... you usually want to have a decent image to begin with. If the image is crappy already... bad JPEG or whatever... you might want the softening that comes from a single large scale... or a couple of larger scales.

 

[namvet]

MindBender .. thanks for that info, am sure I will use it sometime in the future when I get asked "can you fix/enlarge this?" ... all these snippets of info are part of the jigsaw puzzle that is PS .... again, thanks for sharing ..... namvet