Pad and polish combo for ultra red paint

Your yellow pad and 83 should offer enough cut to correct the paint. Are you working the polish long enough, add some pressure on the pad etc, small areas 2' x 2'. Concentrate on a small area, take your time and see if you get the desired results before moving on.
Once corrected you can refine further when the black pad and 80 for more shine

 

I'm having problems with mine too mate and cant decide if the paints ridiculously hard or very soft and marking easily!
megs 101, with a 3m yellow pad and rotary seem to work well on deeper scratches/swirls, then i find megs 205 on 3m yellow or blue pads finish up well, but as soon as it put it in natural light the car looks like its still has defects!

 

Megs 101 is very aggressive and you are probably removing more clearcoat than you need to. if you are not removing swirls/light scratches with that combo then you're doing something wrong. Maybe too large a working area and not breaking the polish down enough.
Renault paint is classed as intermediate and nowhere near as hard as german paint in my obsevations.
My Megane was easily corrected with a white hexlogic polishing pad and Scholl S17.

 

I dont have many deep scratches/ marks on my paint mate, so tend not to use 101 very often on the megane.
i seem to have the same issue as baz is having...correct the paint and it looks perfect under halogen lamps, but as soon as you roll it outside the car has loads of small/very light swirls and looks a mess! so is the paint very soft and marking on wipe down, polishing defects in on the refinment stage or is it very hard and needing alot of work to remove all defects?

i even thought the polish was filling defects, so i use carpro eraser to wipe the panels down and also use plush mf's from cyc.

what colour was your car mate?

 

Just take your time and work on your technique, speeds, pressures.
you need to wipe down with ipa or carpro eraser or the likes as that will remove polishing oils and leave you with the true finish

 

Mine is white mate, not the easiest to spot swirls etc but it was covered when i picked it up from the dealership and it was only 2 months old, thats the sponge monkeys for you at the dealerships.
The paint is not soft imo, ive done quite a few Honda civics now over on civinfo, now that is soft paint, breath on it and it scratches.
Are you sure the small/very light swirls you describe after correction aren't buffer trails from the rotary?
Follow up with a light pad/polish combo, ie meduim-light polishing pad/megs 205 perhaps and this should remove those easily

 

Hope that's helps you guys a little

 

Fo me usually a prewash, snow foam, detar, deiron, clay, and tape up ready for polishing is around 3 hours. An enhancement ie swirl removal usually takes 8-10 hours of polishing alone, iPa wipe down then follow up with your choice of sealant or wax.

 

ultra red is a nightmare to correct. its both hard and soft or rather 'sticky' paint to correct. a combo ive found works is scholl S3 to cut and S20 blue to refine but it is tricky. work the products for as long as you can as it also marrs very easily and unless its fully broken down youll still be putting swirls in.

most heavy cut polishes dont fully break down, only fragmenting meaning these need to be removed with a 2nd stage. poorboys blackhole and a good wax are also a great combo to finish it off.