Jump to content


Photo
- - - - -

photoshop technique I recently learned


  • Please log in to reply
3 replies to this topic

#1 chrisg

chrisg

    Moray Eel

  • Member
  • PipPip
  • 92 posts

Posted 21 August 2003 - 05:19 PM

Here's a technique that is worth applying at some level to pretty much every image. You probably won't find many images which aren't improved by its conservative application. Generally it should be used subtly rather than bluntly to generate a little extra "punch". You should do this before mapping down from 16 to 8 bits (curse you photoshop!).


What you do is apply the unsharp mask. But instead of using a small radius so as to sharpen up edges and give that horrible "over sharpened computer image effect", you set the radius to be very large. For instance, 80 pixels. Adjust the amount to decide how much of the effect you want, and switch preview on and off while changing parameters. You should play with the threshold - increasing it will cause the effect to be limited to the higher contrasting areas in your picture. In particular, its easy to get it to leave the blue water and water surface alone in your wide angle shots. For macro subjects you can better separate them from your negative space.



At this scale, the unsharp mask doesn't act like a sharpening filter - it acts more as a smart selective contrast enhancer. You can't achieve the same effect using curves or other global contrast manipulation tools. It will increase the contrast between the large scale elements of your photo while leaving the fine details alone and not magnifying noise.

I view it as more of a tweaking technique for images that are already pretty good, but I'm sure it is also helpful for images in need of radical
repairs, and if you want to get creative you can produce some interesting unnatural effects.

#2 bobjarman

bobjarman

    Manta Ray

  • Member
  • PipPipPip
  • 404 posts
  • Location:Nashville, TN

Posted 22 August 2003 - 04:55 AM

I learned that technique as a print contrast enhancer. It really makes a good image pop if you don't overdo it.

One caveat, if your image has areas of bright whites it will blow them out if you aren't really really careful.

When I learned this process I was tauht that it should be applied after all other adjustments and right before final sharpening.

#3 james

james

    The Engineer

  • Super Mod
  • 9969 posts
  • Location:Houston TX

Posted 22 August 2003 - 05:55 AM

Thanks Chris - I'm going to try this tonight on a couple of my big animal shots to see if it makes them jump out more.

Cheers
James
Canon 1DsMkIII - Seacam Housing
Dual Ikelite Strobes
Photo site - www.reefpix.org

#4 JohnJohnsonIII

JohnJohnsonIII

    Wolf Eel

  • Member
  • PipPip
  • 199 posts
  • Location:Honolulu, HI or Hamamatsu, Japan

Posted 01 September 2003 - 07:10 AM

Can you post a couple before-and-after shots?
John Johnson - Freedive Photo Fanatic
www.onebreathphoto.com
Canon 20D, Ikelite housing, 18-55mm, 10-22mm, 100mm
dual Ikelite DS-125s, lots o ports...
Olympus 2020/4040/5050
PT-005/PT-010/PT-015
Dual Inon Z220 - the freediver's DREAM
Inon WAL/Inon,Dome Unit
UN WAL/UN Macro