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danielh68
01-07-2006, 01:58 AM
Hi,

I've used Photoshop for quite some time, however yesterday I noticed something that has preoccupied my mind to no end. Perhaps, I'm paranoid, but I swear my pressure sensitive brushes are banding. It almost has a look and feel when one enables the "wet" box although it's not enabled on mine. Has anyone ever encountered this before? Or, am I losing my sanity?

I've read somewhere that occasionally one should delete the preferences if PS is buggy. Unfortunately I failed to locate the file. Well, in any thoughts on this problem will be greatly be appreciated.

Thanks - Dan




http://www.danielhelzer.com/sketches/banding.jpg

Ian Jones
01-07-2006, 05:24 AM
Have you got your brush spacing options worked out?

danielh68
01-07-2006, 07:43 AM
Yeah, my spacing options are fine. I'm beginning to think that's just the way it's suppose to look like. It's just more noticeable when starting with a blank canvas. Anyhow thanks for your suggestion. Much appreciated.

Ian Jones
01-07-2006, 11:05 AM
I can't say for sure, but there's also a possibility it is banding as a result from 8-bit. Seems more likely that its a pressure issue or something along those lines though. Try smudging along the direction of the line to see if its a bit depth issue or something else.

halo
01-07-2006, 04:02 PM
cant see any banding on that pic on my laptop...screen set to 24 bit?

Ian Jones
01-07-2006, 04:28 PM
halo, it's very subtle... look at the stroke on the right, from top to bottom if you look in the center it looks like a very subtle spacing issue. This is quite subtle of course, but you should be able to just pick it up with good eyes.

danielh68
01-07-2006, 04:51 PM
Thanks for your interest guys.

1. I checked my desktop properties and it's set at 32 bit.

2. I tried what you suggested, Ian. I didn't use my tablet though. I just selected the smudge tool and dragged the mouse over the area circled in green. As a result, I got these discolored banded waves (at least that's what I see on my end). Then again, I don't use the smudge tool so maybe that's what it does, but I was expecting something different.

I've tried reinstalling PS and it didn't change anything. I zapped the preferences, no luck either. Then, I imported the file into Painter and I believe it's much better to work in. I don't see the aggresive banding as I do in Photoshop. I have version 7, I might just invest in an upgrade and see if that remedies it.

http://www.danielhelzer.com/sketches/banding2.jpg

Jack Youngblood
01-07-2006, 11:31 PM
I get banding sometimes, especially in large flat areas of gradients. It seems to depend on the document size/brush size ratio.

I usually get rid of it by doing the gradient/brush stroke small then scaling it up.

danielh68
01-08-2006, 12:43 AM
Thanks, Jack...I think you're right. It's more prevalent with a large brush. I guess, I never paid much attention to it until now...then I began obsessing about it. I just gotta step back and let it go.

Thanks again.

halo
01-08-2006, 09:54 PM
Thanks for your interest guys.

1. I checked my desktop properties and it's set at 32 bit.

2. I tried what you suggested, Ian. I didn't use my tablet though. I just selected the smudge tool and dragged the mouse over the area circled in green. As a result, I got these discolored banded waves (at least that's what I see on my end). Then again, I don't use the smudge tool so maybe that's what it does, but I was expecting something different.

I've tried reinstalling PS and it didn't change anything. I zapped the preferences, no luck either. Then, I imported the file into Painter and I believe it's much better to work in. I don't see the aggresive banding as I do in Photoshop. I have version 7, I might just invest in an upgrade and see if that remedies it.

http://www.danielhelzer.com/sketches/banding2.jpg

is that a scan? if so thats "newtons rings"...caused by interference normally caused by a scan subject normally popping a little of the surface of the scan. Try a blur on that area and see if it goes away, If not i'd say its a cymk document...or perhaps an rgb colour space with a limited tonal range in the colours your using.

i can see the banding on the paint brushes now...looks like a spacing thing...try setting spacing to 0 and see what occurs.

if you really cant get rid of banding, add noise...even doses up to 5% are unnoticable in screened print (but can show in screenless printing or on the web)....blurring banding that occurs to gamut limitations wont solve it.

Jack Youngblood
01-08-2006, 10:37 PM
Yeh... Ive seen multicolour marks like that on a scan. caused by slight dampness of transparency. Often this dampness comes about from change in environment of transpaency.

Solved by leaving the tranny in the target environment for a while until it warms up.

Whipyo
01-08-2006, 11:03 PM
Hi Danielh68,

Photoshop brushes do band for me too...but there are a couple of things you can do to minimize or reduce the banding. There are just certain colours and situations which show up the banding worse than others.

1 - Turn on the noise setting in your brush. You will get no banding at all if you use this setting but sometimes the noise itself if too strong and just undesirable.

2 - Add some grain to your image. Instead of just simply adding noise, create a new layer on top. Fill with 50% grey (Shift-F5 and select 50% grey) and set the bliending mode of the layer to 'overlay'. Then add about 10-15 noise (I usually use coloured noise but sometimes I use mono noise on skin tones etc..). Then you can use Guassian blur on this layer. The amount of blur I use depends on the image...For me it is about 0.5 - 1 pixels. You can then play with the layers opacity slider until you are happy with the strength. I usually set my grain layer to something like 15-50% opacity.

Images which have had this treatment always seem to look and print better. If you do heaps of cloning and smudging and softening on an image, this is also a good way to 'regrain' an area so it looks natural again. You could apply a mask to your 'grain' layer to just have it in certain areas.

Using 16-bit mode will also help reduce the banding but you can still get it in certain situations. Also be aware that if the image is to be used for print that most RIPs internally convert 16-bit images to 8-bit anyway so you lose that extra information and the banding returns.

I personally do not think that deleting the prefs will help this situation - it is just a matter of how the brushes work.

Painter doesn't have these issues because their brushes work differently to Photoshop. If Adobe bought Painter and integrated that with Photoshop it would truly become the killer app.

Hope this helps.

Whipyo

danielh68
01-08-2006, 11:29 PM
Thanks everyone for the great advice. I've learned a lot from it :thumbsup:

Whipyo, those are some excellent tips that I will surely put into practice from now on, Thanks!

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