Help with colours and technique please!

I'm an amateur but I use a palette knife to do rocks/cliffs and when I can't get the right shade of green, I put them down and get a green from using black and yellow. I'm sure the experienced artist will give you great advice.

Try ultramarine and burnt Sienna plus a hint of white to lighten it as a warm grey. Payne’s grey is cool and mixed with white is not the way to go here. It will look flat and dead! You could try lamp black and a yellow as Denise has suggested, but there are so many ways to mix green. Black and lemon yellow will give you a good Spring green for instance. Go online and you’ll find lots of colour swatches to help. Think texture for rocks (impasto) yes, a painting knife would be useful as well as some confident brush work! You could think about scumbling, but I’ve never tried it with acrylics, no doubt Robert can advise here. It’s important to think ‘mixing’ at all times, experiment and don’t use paint straight from the tube (generally).

https://www.jacksonsart.com/blog/2017/06/13/mixing-greens-in-oil-colour/ This is a link to help with mixing greens. It’s oil colour but the same principles apply.

Avoid Paynes grey - it has its uses, but they're few and far between.  Scumbling, which Alan mentions, is a good technique in acrylic, as is glazing - same principles apply as with oil paint, but the paint dries faster - light over dark works well for scumbling, brushing the paint on in broken fashion (heavy duty acrylic is best for that, with a minimum amount of water or medium, and preferably none).  Greens - ah....  you have two or three very distinct shades of green in that photo, and the actual scene, were you there, would probably show a good many more.  The duller greens can be obtained with Ultramarine and Yellow Ochre or Raw Sienna; bright greens with Cerulean or Cobalt Blue and Lemon Yellow or Cadmium Yellow Light; extremely vibrant greens with Pthalo Blue and a range of yellows, or Pthalo Green, plus yellow, or Burnt Sienna.  And a really good deep green can be got with Pthalo or Prussian Blue with Burnt Sienna, or Burnt Umber - useful for deeper shadows. Some of the ready-made greens are useful, but not on their own - Sap Green, Oxide of Chromium, Viridian (Hue) - the actual viridian pigment isn't available in acrylic, the hue colour is likely to be a softer version of Pthalo Green; Hooker's Green - a generally deeply unappealing colour on its own in any medium, is a good mixer.  As to what you mix with them, reds will dull them, yellows brighten them, earth yellows will take them to a more neutral hue.  I've never had any success with mixing black and yellow in acrylic, but you might - experiment on bits of practice paper.  You'll need a touch of white with most of those mixes, but not the deepest ones.  Glazing can help with atmosphere and distance - and you can glaze with mixing white or zinc white as well as with colour.  A Cobalt Blue glaze can push the farther slopes back - mixed with a little W & N Mixing White over the more distant greens, for instance.  It's true in all media, though, that the thing to concentrate on when trying to convey scale and distance is tone, more than colour - which is one reason why Payne's Grey and white isn't a good idea, unless painting in monochrome - Payne's can be a sooty near black, or an equally sooty dark blue - used in the foreground for rocks, you're going to get the most basic and dullest tone, offering few opportunities for effective contrast; tone without colour may not be quite so bad as colour without tone,  but Alan is quite right that it'll leave your painting looking flat (and your rocks looking like the sides of a battleship).  Buff Titanium might be worth a try for the rocks, darkened where necessary with your shadow colour of (again, back to Alan) French Ultramarine and Burnt Sienna - or a green and a red; even Sepia, if you have it.  But a mixed shadow colour always seems to work a lot better - to be strong, but not intrusive: the Ultra + Burnt Sienna mix keeps your darks in their place.  

My main problem seems to be that I'm always trying to find a quick way to a result , and today I have wasted too much paint trying to get various colours and have ended up with colours I dont want and have had to get the turps out .  What might members suggest ? and are those colour wheels any good  ? . Stephen Weight

The best colour wheel - arguably - is based on the best palette; in this case, a split palette consisting of a warm and cool version of each primary, plus a few helper colours.  The Michael Wilcox School of colour palette is a good guide to start with, though I do supplement it with some convenience colours. in brief, obviously you need white.  Then a warm and cool variety of the other fundamental hues, so, and eg: A scarlet, orange-inclining red, like Cadmium Red or Vermilion; a crimson red, like Alizarin Crimson, Rose Madder, or Permanent Rose (usually variations on Quinacridone violet or magenta); an orange yellow, like Cadmium Yell, and a cooler one leaning towards the green end of the spectrum, like Lemon Yellow; a warm blue, i.e. inclining towards purple - Ultramarine is the only one that really qualifies as such; and a cool, greenish blue - which could be Cobalt, Cerulean, or for sharper, stronger blues, Pthalo or Prussian. With those colours alone, you could keep your palette simple and produce some effective paintings.  But to go further, you'll probably need one green - Wilcox recommends Pthalo, I recommend Viridian, a transparent earth yellow, like Raw Sienna, an opaque ditto, like Yellow Ochre; an earth red, like Burnt Sienna, is just about essential to most painters; and you could quite easily stop there, and learn how to mix the colours you want. My little e-book Oil Paint Basics, available on the Amazon Kindle store, goes further into this.  There are also books, such as 'Vibrant Oils', by Haidee-Jo Summers, Virgil Elliott's "Traditional Oil Painting" - which may be a little bit heavy to start with, Alan Bickley's articles in The Artist magazine, most if not all available on the website here.  The important thing at the outset is to learn how to mix the colours you really want, and avoid having to scrape or  Turps them out - you won't always want to stand by the old reliables: introducing other colours for interest and variety - eg, Winsor Red/Rowney Red, the Mars range of synthetic earths, Cobalt Green, Terre Verte, Terra Rosa, and many others can come later, when you're sure you can at least get your basic mixes right and reasonably predictable.   If you're finding you're mixing unsatisfactory colours, you may be using too many in one painting, or not using those which work best with each other.  Bearing the above in mind will help you - learning to mix coloured greys, what colour you choose to tint your canvas before starting to paint, all of those steps need to be learned - you say you're in too much of a hurry: well, combine that with not necessarily understanding the basics of colour mixing and yes, you're going to be in trouble. I'm not here to sell, and my book isn't expensive anyway, so I would say - it does answer many of the questions you've asked here and which are holding you back; it also contains suggested colour mixes.  Might have been written with you in mind, but wasn't - it was written with me in mind, because those are the questions to which I sought answers when I began painting over 50 years ago: I had to learn the hard way, and it took a long time!

I’ll be brief on this one as Robert has addressed most of the relevant points. In too much of a hurry is definitely not the secret to a successful painting, why do you need to be in such a hurry?  Yes, get a colour wheel and Robert has given good advice here. Use a very limited palette to start with and learn how to mix your colours, it’s not difficult!  Too many colours can be a a disadvantage in the wrong hands, you don’t need them! Finally, I agree again here, PaintersOnline have put out a wealth of practical information on this site, so use it. I’ve got a lot of useful information on oil painting techniques which has been taken from some of my articles in The Artist.

Alan - comments appreciated as always. Thanks Stephen weight

Thanks Stephen! Perhaps start your own colour mixing chart, simple squares of your mixes with what colours used etc - I do this and find them really useful to refer to occasionally!