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Tale of two compressors

20171018_162205.jpg 80 gal 17cfm Quincy 150psi at wall.
20171018_162446.jpg 30 gal Harbor Freight 7cfm 150 psi.

Same gun, same settings. Spraying at 29 psi.

I get better results with the Harbor Freight tank.

The Quincy looks likes the pattern is split.

Any ideas why this might be happening?
looks like the gun needs readjusted for the extra volume of air the Quincy is providing. Air volume even at the same PSI changes the game. the one thing that I keep thinking of is when I was working for my friends dad that has an excavating Co. and we were doing a new development and installed the sewer lines and had to pressure test the 10" pipes. We had capped and banded each open stack and I was told to make sure they were TIGHT we put (I think 20psi) in the lines, he hooked up a Diesel powered air compressor to fill the lines and the tops were popping off and shooting 10ft in the air and I cranked on them (I thought) we recapped the lines and I hossed them tighter then hell and they held but dam they had to be tight and with only the small amount of PSI that PSI at that volume pushes harder then you would think. That is the only thing I can relate it to, someone can chime in if my reasoning is wrong.

Also a 100psi spray can blowing up is far different then an 80gal tank given the air volume and 100psi through a drinking straw is different then 1/2" air line volume changes things.
It could but also fluid. It all depends on the gun because each gun has it's own spray setting needs and those can change when equipment changes. Also technique might need to be adjusted also.

I could be off on my reasoning of the physics behind the extra volume but do know when ever I spray in a different setup the gun needs readjusted and that is the only thing I could rationalize. Barry has a very good understanding behind the effect the physics play on the gun.
I used reducer to spray for the pics. Only differences, besides the compressors is that the Quincy has a 30ft hose and the HF has a 50ft.
The Quincy has a motorguard paper filter and a QC3 filter. The HF has just the paper filter.