How to Sharpen an Image for Zooming.

Traverse

macrumors 604
Original poster
Mar 11, 2013
6,744
2,934
Here
Hi,

I'm not very experienced with digital photography, but I'm trying to hand draw a digital picture I have. Unfortunately, the image is like 400x600.

I need it sharper for zooming in so I can perfect the fine details. I tried enlarging the photo in Preview and raising the PPI. These helped some, but not great. I know there is no way to turn a low res picture into a massive work of art, but are there any other ways I may sharpen the picture?

Thanks
 

Zaphyrus

macrumors member
Jun 20, 2013
46
0
Just to be sure, when you're resizing (in Photoshop I'm assuming), are you making sure resample is unchecked when you're raising the PPI? Sometimes people forget it's checked and Photoshop will try to add pixel and information that isn't there. However, if you are lucky enough to have this image be 400x600 at 300 PPI, you can lower the PPI to something like 150 with resample unchecked/constrained proportions checked and it will resize it to 800x1200 which should be large enough with enough detail to work with(typical PPI that's acceptable for most inkjet prints these days). If this isn't the case, keep the settings the same and raise the resolution. I guess resizing is like working with sand in a sandbox. You can move the information around to be bigger in size or more detailed, but you can't add more sand if it isn't there.

Hope this helps!

----------

As far as sharpening, I would try high pass sharpening since it sharpens up the edges versus the entire image making it chunky/crunchy looking. To do this:

1. Make new layer copy of your background layer
2. Desaturate layer (Shift+Cmd+U)
3. While layer is selected, go to filters > other > high pass
4. Set this to around 2-3 pixel
5. Hit okay and set this layer's blending mode to overlay
Hopefully this'll help bring back some sharpness

It's typically used for output sharpening to bring back sharpness lost after altering the original image.
 
Last edited:

Traverse

macrumors 604
Original poster
Mar 11, 2013
6,744
2,934
Here
Thank you so much for your detailed reply! I will keep it for future reference.

Unfortunately, I don't have photoshop at this time. All I have is iPhoto and Preview, but I will keep your advice on hand for future situations!

Your Awesome! Thanks!

----------

However, when I was resizing it in Preview I did have "Resample" checked. I will try again without this option to see if I get any difference, Thank You!
 

LongSticks

macrumors 6502
Jul 22, 2012
301
0
Kent, UK
Long shot but try this!

Thank you so much for your detailed reply! I will keep it for future reference.

Unfortunately, I don't have photoshop at this time. All I have is iPhoto and Preview, but I will keep your advice on hand for future situations!

Your Awesome! Thanks!

----------

However, when I was resizing it in Preview I did have "Resample" checked. I will try again without this option to see if I get any difference, Thank You!
You need to get more data in the low res image than you have, to be able to then zoom and sharpen etc. There is a way to add more data - usually needs larger images than you have, but its a free trial so worth a shot.

Try this fractal software to process your image and see if it enhances your detail on zoom - www.ononesoftware.com/products/perfect-resize/
Perfect Resize 7.5, formerly Genuine Fractals, increases image size faster than.....

Good luck!
 
Last edited:

Traverse

macrumors 604
Original poster
Mar 11, 2013
6,744
2,934
Here
You need to get more data in the low res image than you have, to be able to then zoom and sharpen etc. There is a way to add more data - usually needs larger images than you have, but its a free trial so worth a shot.

Try this fractal software to process your image and see if it enhances your detail on zoom - www.ononesoftware.com/products/perfect-resize/
Perfect Resize 7.5, formerly Genuine Fractals, increases image size faster than.....

Good luck!
I may try this, Thanks!