aged concrete test photo #1

[tom mann]

I think you could achieve the effect you want for tar by simply brushing on full strength black acrylic paint. 

Actually, this would probably work.  I would like something that has more of a 'tar-like' appearance, though.

[wm3798]

Use gloss black, and maybe thicken it with some white glue.  Although that might add some unwanted translucency...

Lee

[DKS]

Use Testor's Gloss Black paint in the little hobby bottles, and add some talcum powder to make it pasty. That's about as tar-like as I've been able to conjure.

[Philip H]

Just for the look of fresh tar dribbled by a DPW guy - ultra fine point Sharpie markers.

[Sokramiketes]

I added a wash of Ivory Black last night to darken it to resemble asphalt.  Looked good.

Now, what can I use for the tar for crack filling?  I was thinking plumbers putty.

Whoa whoa whoa... Concrete and asphalt are two very different animals with very different and distinct craking patterns.  What you have so far is cracking like concrete, across slabs, it is not the edge deterioration and crumbling of a typical asphalt road surface...  Coloring is not the only factor.   

[tom mann]

Yes, but this is just a test! ;D

[wm3798]

True enough, except in the case where the asphalt is overlayed on an old concrete surface, then the cracks will pretty much follow the same pattern as the sub-base...

Lee

[Chris333]

I'm undecided on how it looks. I need a overall whole layout shot to know for sure 

[railbuilderdave]

I really like the cracks you got on this.  How did you do the test?  For the color I think it's been said there are many different colors depending on age and other factors.  You need to get proto photos of an area like that you want to model.  I've been doing some cement studies and find the most important is the age you are trying to model.  Please share more samples as you get them.
Dave

[Sokramiketes]

I'm undecided on how it looks. I need a overall whole layout shot to know for sure 

Whoa... Chris with the TKO.