Chris: If that works for you more power to you. I've never had much luck with washes, they always seem to make a mess for me so I prefer the control the airbrush gives me. I normally only use spot washes.

One other issue is I guess the investment depends on how much you use it too. I do a lot of US olive drab subjects so I get a lot of use out of them. If you only build a Sherman once every few years of course a twenty dollar set of paints would probably be a huge waste.

Raualduke: Basically the concept of colour modulation is painting something generally a single colour like an US tank thats all olive drab (OD) several shades of the same colour. Aka: paint the lower parts and shadowed areas slightly darker OD, the sides base OD, and the upper areas in the direct sunlight with lightened OD. The AK Products set includes six shades- including a light and dark shadow tint and a light and super light highlight. The Doog is more of an expert on this than me.

I've read several articles on color modulation and still can't get my head wrapped around it. Can anyone explain it it laymens terms?

There is no right or wrong color modulation technique.  I see benefits of AK sets for people who don't like to mix their own custom colors.  Having said that, I simply brush oil washes (MIG oils + Mona Lisa thinner) of varying shades to modulate a base color.  I used to mist tan or black, but I find oil washes to be more convenient and fool-proof.  

John: The stuff is acrylic so it dries really fast, normally I paint the hull and then do the turret. By the time I'm done with it the hull is dry and ready for the next shade.

Chris: You have a point there- I could just add a little tan to the olive drab each time. It's just the AK product is pre-mixed and ready to go. It eleminates all the guess work so I can just keep moving. If you're doing six different shades like the AK system uses just the mixing can take some time- and if you screw up you generally need to go to the beginning and start over.

As Duke says it comes with six shades, shadow, dark base, base, light base, high light, and shine (top high light). If I'm just doing two or three shades mixing myself isn't an issue.

I guess in the end it's just that I'm lazy and want to drop a few steps and think the extra expense is worth it. And as I've said by using Tamiya paint as an undercoat and the first shadow colour I don't need to use much of the AK product. I've done two Shermans and two helicoptors so far and still have lots of paint left. Twenty bucks over a dozen or so models doesn't seem like that much of an investment to me.

Only big issue I've had so far is the Russian set I bought the paint seems a little old and has some lumps in it. It clogs up the tip on the dropper bottle leaving you to pull the cap off and mix up the paint- killing much of the advantage of using the pre-mixed paint.

Good results can be had,but they are not magic bullets,they take practice to really master the technique.

I have to agree with Gamera here. While it is certainly possible to just go to the next color in the available pallette, the AK system has multiple minor gradations that make the range of modulation easier to achieve. It's also helpful for some to be thinner so they are more transparent around the edges. The AK system is expensive, but it partly just means you won't be using up your Tamiya paint.

Gamera

The set makes everything baby simple- just squeeze a few drops into the colour cup on your airbrush and spray. Don't even bother to thin it.  When done move to the next lighter shade- you don't even have to wash your airbrush out. Personally it allows me to rip though a tedious job in less than an hour or so.

If the above describes how you paint, you can do the same with other paints.  For example, spray Tamiya Dark Yellow and move to the next lighter shade like Desert Yellow.  You don't even have to wash your AB.

Gamera;

Just curious how long you wait between the Vallejo coats?  Just curious as to what you have found to work as you said you can get it done very quickly.  I have always been a bit wary of spraying over a coat too soon.

John

Guess I have to take the opposite tack here. Yeah, it's not that hard to add a little tan etc to your base coat but after trying one of these sets I love it. The set makes everything baby simple- just squeeze a few drops into the colour cup on your airbrush and spray. Don't even bother to thin it.  When done move to the next lighter shade- you don't even have to wash your airbrush out. Personally it allows me to rip though a tedious job in less than an hour or so.

In my opinion if you're going to work though five or so different shades in the modulation it's more than worth the money just for all the time and trouble you avoid.  If you undercoat with something like Tamiya olive drab before using the US set you only use a dozen drops or so out of each bottle. I've done about five models so far still have enough to paint probably a dozen or so more models.

I agree with Chrisk-k.  I am not saying they are bad products.  But you can lighten and darken any color with other colors and techniques.  Of course if you want to have it all pre-made and ready then they would make sense for you.

John  

In my opinion, AK or Vallejo modulation sets are not worth buying. You can achieve color modulation by a variety of methods.  To lighten an area I would mist Tan or apply a light wash.  To darken an area I'd mist a color darker than a base coat or apply a dark wash.