If I make a new layer over an image...

fill that layer with a colour...

Use the clouds filter...
can I then:

a) somehow arrange for this layer to have a gradient of visibility with the layer more visible at the bottom of the image, and fading to total invisibility at the top of the image

and or:
b) somehow get an eraser that will remove parts of this layer to let the image below show through but have the eraser use a soft edged brush effect and not jump around like it does now,

• now I get a hard edged brush and as I move the mouse (or the pen) I get lots of impressions where the tool went, like someone stamped down with the eraser like a hole punch, multiple times.

I'm sure I've seen this somewhere, is it to do with masks?

I think I learned about it (and then never used it again, thus forgetting) on a photography course once long ago.

You might try using a soft brush set to airbrush for the erasing. 
Sorry I can't be more help..  I've never really done anything with mist/fog.. 

Trouble is I just don't understand how to make the eraser do anything else.

I tried airbrush, makes no difference.

I tried altering flow, and opacity - didn't help.

Well..  I tried to make some mist but this monitor just distorts the color so bad that I gave up. 

Maybe if you try painting (soft airbrush) it in layers, adding a cloud pattern, then adjust the opacity for each layer you could get the gradient look. 

I'll look into that idea, you mean paint the mist rather than trying to erase away the mist?  Might work.  Thanks.

Meanwhile knowing that there are some Bryce artists who use mist in postwork I asked in the Bryce forum too.

There used to be some mist/fog brushes in the MP..  Maybe a google/yahoo search would find you some free ones.. 

I just made a cloud brush... only I'm supposed to delete the original now I have an adjusted one, but my photoshop isn't telling me brush names when I hover over the brush, so I can't tell which is which.

Do you know how to get the brush names thingie working on hovering?

Quest posted a nice 'cloud brush making tutorial' - my first brush!  It was (up to this point,) so easy!

I'm sorry Fran.. I don't know where the settings for brush names are.  I wonder if it would be in PS preferences or properties ?? or a setting in the pc??? 
Where did Quest post the tut?  I'd like to save it for future reference.. 

Attached Link: http://www.biorust.com/tutorials/detail/229/en/

Chuck

Attached Link: http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2765879

Set your foreground colour to black and your background colour to white
Create a new layer.Get the lasso tool and draw a rough cloud shape about half the size of the layer.
Go to Filter - Render - Clouds.
Hit Control and T...this will select the layer.
Get hold of the handles that appear and stretch the cloudy image...it will atart to look loike fog.
If it is too much in the layers pallete reduce the opacity.
If you need more mist...duplicate the layer and move the mist to where you want it or again hit control and T and stretch it agian.
Get a soft edge brush and set the opacity to about 10 or 15.
Brush over the mist with white to create some highlights or black to make bits darker.

Quote - Use the clouds filter...
can I then:

a) somehow arrange for this layer to have a gradient of visibility with the layer more visible at the bottom of the image, and fading to total invisibility at the top of the image

You need a layer mask for this. Once you've done the clouds filter on a new layer, set that layer to screen blending mode, which removes the black and leaves only the white. Then click the layer mask button to add a mask to the cloud layer. Select the gradient tool and make sure the selected gradient is black, white and that the gradient type is linear. Now draw a vertical gradient from the top of the mask to the bottom. You should see the clouds fade out at the top of the layer. If they fade from the bottom, undo and draw the gradient up instead.

Quote - and or:
b) somehow get an eraser that will remove parts of this layer to let the image below show through but have the eraser use a soft edged brush effect and not jump around like it does now,

To do this, select the eraser and ensure it's set to brush rather than block or pencil. Choose a soft brush from the brush palette. Press F5 to get the brush editor, check other dynamics and in that tab set flow to pen pressure. I usually set size jitter in shape dynamics to off, but that's just a personal preference. You should find you have a much more responsive eraser; it may also help to turn off the visibility of all other layers as well, to speed up the display.

Thanks much for the link Quest..
I love your avatar..

try the "glitterato" plugin from flamingpear.com

just use the basic default clouds, reduce the stars to zero and then set as a new layer on top in 'soft light' or 'screen' mode

you can squish and distort the layer and use a diffuse brush to erase edges etc and then copy the layer and put it on top of tanother, twist, fold, mutilate and spindle until it looks right with the layer effects and layer modes etc

see this pic that I did doing all that --> http://www.seanellery.com/gallery/albums/userpics/trex.jpg

cheers
Sean

For future reference another very simple way is when you are out and about take a few shots of cloudy skys.
Open one of them.Get the lasso tool and mask part of it...copy and paste to the image you want it on.
Hit control and T and stretch it until it looks good..
Fade the opaciy of that layer to your liking.If you need more duplicate the layer and move the mist to a new position.....much simple than brushes and gadgets.And you always have the original.
Dodge and burn a bit for a bit of contrast.

I don't have Pshop open at the moment so I'm not 100 percent sure, but set your eraser to use a soft brush, then up on top of the tool bar there should be an option set the percent of effect, so you should be able to set the eraser to just erase a little at a time until you get the effect you want.

Try DeviantArt... there's a whole lot of free brushes for non-commercial use in their Resources area. Some of them are mist brushes, but you might want to check other sets too.

www.deviantart.com/#catpath=resources/applications/psbrushes&order=9

Thanks lorenzo1974, I've got some really nice brushes from DeviantArt.

bonestructure,
You mean percentage of opacity.... or maybe percentage of flow?

ejn,  "Get the lasso tool and mask part of it..."
mask part of the lasso tool?  How?  or mask part of the image you've just selected with the lasso?  How?

I'm just so not 'with-it' on masks.

SeanE,
Um thanks, but I really can't afford anything just now, so I'll have to pass on Glitterato.  Nice mist around the dino's feet, in that image.

spedler,
What percentage should the "Other Dynamics" be set to? They are at 0% at the moment.

ejn,
Interesting way of doing it, and simple to remember too, thanks.

SWAMP,
Oh SWAMP what have you done!!!

I now spend a good part of my time at BioRUST, what a fascinating place! and Unleash has really helped me kickstart some more modeling.

"You mean percentage of opacity.... or maybe percentage of flow?"

Well,  look at it as percentage of opacity if you like. It's really percentage of effect. Almost all the tools have a slider up top. Like, if you use the burn tool, set the slider at 50% and you get 50% of what the tool does at full use. I find it very useful to set the effect % down. If I want a stronger effect, I just go over the area again.

Quote - What percentage should the "Other Dynamics" be set to? They are at 0% at the moment.

Leave opacity jitter set to 'Off' and 0%, and have flow jitter set to 'pen pressure' and 0%. If you up the jitter all that happens is that you get a lot of variation in the erasing effect rather than it being directly controllable with the pen.

bonestructure, > Quote - "You mean percentage of opacity.... or maybe percentage of flow?"

Well,  look at it as percentage of opacity if you like. It's really percentage of effect. Almost all the tools have a slider up top. Like, if you use the burn tool, set the slider at 50% and you get 50% of what the tool does at full use. I find it very useful to set the effect % down. If I want a stronger effect, I just go over the area again.

Well no, it's not a question of what I like, I was asking since I couldn't tell what you meant me to be adjusting, I'm looking at Opacity and Flow on the top menu bar of PhotoShop - what else could you mean?

A slider up top?  Up top of what? where?

spedler,

Yup, that's what I have it set to.  Good.

You click on the arrow next to the % window and it pops a slider down that you then adjust. Extremely useful with all the tools.

The brush settings should effect the eraser just the same as any other brush, if they don't then something is wrong.

I would set both zero hardness and reduced opacity, so that it takes several strokes to actually erase anything. As bonestructure said, you get a bit more control that way.

Thanks for the screen cap, but you are talking about the burn tool there and we were initially talking about the eraser tool since I wanted to erase.

And with the eraser tool you get this: (see pic)
And as you can see there are 2 controls with percentages there, not just one.

One is called "opacity" and one is called "flow"....
I am unsure because I guess I have not really noticed any change when adjusting percentage of flow, and so I don't really understand what percentage of flow is supposed to be for, when it has so little effect on anything.

Opacity on the other hand does have an effect, at least, I have been able to see an effect when changing it.

So... probably just stick with opacity then...

Oh, wait a minute... are you maybe saying that using the burn tool instead of the eraser tool might have a better effect?

Dear prixat,

Thanks for your screen capture image, it makes it so much easier to understand when there are what amounts to multiple conversations going on. Lol.

Right, okay - change hardness as well.  I'll try that thanks.

No, I was just using the burn tool as an example because that's the tool that was open at the time. In the case of the erasor, it's the opacity slider. But really, it's the same slider for every tool, just changes names for the tools. It's a percentage of effect. In this case, the lower the percentage of opacity/effect, the less it erases. In this way, you can make your mist more or less solid. At 100% it erases everything. at 0% nothing. Everything in between is just a gradation of the effect.