RP Tutorials - - The Stepwedge and why to use it

Doug Nelson · #1 07-27-2003, 10:18 AM

Ever wonder why a stepwedge is our logo? That's because it's one of the most useful tools in image editing (Photoshop 7, but any editor will work) [details]

gina · #2 07-28-2003, 01:36 PM

Thank you very much!
I used the stepwedge before but I never thought about using it in Photoshop.
You opened my eyes for this enormous help!

Thanks again

Gina

ps : do you enlarge your canvas and put it on every layer or what?

Ed_L · #3 07-28-2003, 02:13 PM

This is an excellent tutorial. I've seen this before, but I don't remember it as having so many illustrations. Did you edit it, or am I getting (more) old?

Ed

Doug Nelson · #4 07-28-2003, 03:50 PM

Brand new, from scratch. Took me about 20 minutes total with the new tutorial publishing system.

drhiii · #5 09-08-2003, 02:07 AM

Quote:

Originally posted by Doug Nelson
Brand new, from scratch. Took me about 20 minutes total with the new tutorial publishing system.

Hello... a newbie to Photoshop and have a question... have created the Stepwedge strip and have to say this is a very smart idea. Below is a quote from the tutorial. Question is... how do you "drag a copy onto the border of any image"? Am a bit lost on that one. Any help would be much appreciated.

drhiii

Finally, use Image > Adjustments > Posterize set to 21 steps. This will provide a stepwedge with even steps of 5% difference from each neighbor. Save this after flattening as a PSD or TIF file, and drag a copy onto the border of any image you're working on.

Stephen M · #6 09-08-2003, 03:50 AM

Hi Doug, I have a couple of small additions to your excellent tutorial - on the mechanics of constructing the gradient.

i) As we all know, grads often band. This is why the gradient tool has a 'dither' option to add subtle minor noise to the gradation, which is a very good thing for print reproduction, but not for small web files or for calibration step wedges as being discussed here. So uncheck the dither option when making a grad for posterizing.

ii) Different working spaces use different gamma/dot gain - which affects the gradation. This is why the posterized gradation does not have even width patches from highlights to shadows. There are two options to fix this issue when making a calibration grad, but perhaps not for a regular gradation:

* Set the SMOOTHNESS option to zero (0) for this calibration gradient (in the gradient editor).

or

* After constructing the gradation, run the Equalize command over the gradation (if using 100% smoothness).

One may choose to select most of the gradient for posterizing into steps, but still wish to leave a full width section as a gradation strip over or under the steps.

Please feel free to incorporate these tips into your tutorial.

Regards,

Stephen Marsh.

Doug Nelson · #7 09-08-2003, 10:46 AM

Quote:

Originally posted by drhiii
Question is... how do you "drag a copy onto the border of any image"? Am a bit lost on that one. Any help would be much appreciated.

With both documents open (your working document and the stepwedge document) click and hold on the stepwedge layer icon and drag it over onto your working document. It will be added as a new layer.

drhiii · #8 09-08-2003, 02:33 PM

Quote:

Originally posted by Doug Nelson
With both documents open (your working document and the stepwedge document) click and hold on the stepwedge layer icon and drag it over onto your working document. It will be added as a new layer.

Got it. Understand. Simple. Too simple as I tried many other ways... tx for the time to help...

drhiii

Phil Phil · #9 11-19-2003, 06:06 PM

Hi Doug,

I'm new to the forums, and relatively new to PS, so any help you can give me will be greatly appreciated.

I have read your tutorial on stepwedges, built one, and pasted it into my image as a layer. Now, and this will give you an idea of how unenlightened I am, I can't figure out how to use it. How do I get it to reflect the operations (eg Levels, Curves, etc.) that I am performing on my image?

I am intrigued by the use of the stepwedge, to give me an understanding of the impact the various tools will have on my images, but I've spent a couple hours on this and come to a dead end.

(The only work I do in PS is to improve photos that I have taken myself.)

Regards, Phil

Doug Nelson · #10 11-19-2003, 09:14 PM

If the stepwedge is on the layer of your photo (or below) it can't help but reflect any global adjustments you make. Or you can just leave it on the layer above your image and just make sure all adjustment layers are above it.

Don't think of it like a meter or something else you need to watch constantly. Just as a kind of guide to let you know exactly what you're doing, especially if you're doing something inadvertently destructive.

And in typing this it came to me that maybe you're not using adjustment layers? If you're using the stepwedge on a separate layer and then making non-layered adjustments, you're right in that it would be rather useless (again, unless you merged it to the image layer).

But I do recommend adjustment layers if even remotely possible.

Phil Phil · #11 11-20-2003, 12:04 AM

Thanks Doug.

You were right: I was not using adjustment layers. Somehow, in all my reading, I missed them.

Well, another step forward. Sure appreciate your help.

Thanks, Phil

Ron Hirsch · #12 06-22-2004, 05:08 AM

Interesting material on using the stepwedge for an image already taken. While I use stepwedges often, I never considered adding one to an existing image during retouching et al.

Would it not be even better to include a stepwedge in an image during the taking of that image? It seems that a greater capability would then be available to evaluate exposure, color balance, etc..

I've been trying to locate a utility which would run a PS action or script on an 10 step wedge in an image which included a 10 step wedge during the taking. At each step, the RGB components of the step would be analyzed, and adjusted via Photoshop curves to get the proper levels and color balance. This would in essence create an instantaneous "profile" for that image, based on the wedge's density and RGB components.

Of course, the user must have a professionally created hard copy of the wedge to include in the image, when taken.

I read an article by Taz Tally in Photoshop User that was in this realm, But after endless tries to get more info and contact Taz, I gave up trying.

It does seem to me that the package of a hard copy wedge, and a script/action for Photoshop to do this would be a very worthwhile item.

Ron Hirsch

cisco · #13 11-29-2004, 02:06 PM

Great! The step wedge can also be used to demonstrate that your edits to an image are completely safe.... er.. thats if a photog happens to be standing over your shoulder doubting your capabilities... not that that's happened to me r anything.. jusss sayin yknow

great tutorial and good idea Ron, hope to read a follow up on that one.

margery · #14 08-28-2007, 12:02 PM

I'm a very new member. Read thru tutorial and some of discussion but still need help. Question: To drag step wedge onto image, do you create a canvas? (If so, what is the background color?) Or a "new layer" on which step wedge is placed? Doesn't step wedge have to appear on screen in order to serve the purposes you describe?
Thanks greatly.

Doug Nelson · #15 08-29-2007, 01:25 AM

If an image is open in your editor, there is already a canvas (you can't have an image that's not on a canvas). If you drag or paste the stepwedge into another image, it should automatically create a new layer. And yes, you must be able to see it to use it (but since it's on its own layer you can drag it around and toggle its visibility off when you don't need it).

Welcome, and hope this helps.