Electrical – Voltage follower with antique lm308 op amp

I'm playing with an antique LM308 http://web.mit.edu/6.301/www/LM108.pdf
For some simple tests I've wired it as a voltage follower.

^{simulate this circuit – Schematic created using CircuitLab}

Now I'm trying to understand my measures :

• 0V <= Vin <= 600mV Vout = 600mV
• 600mV < Vin <= 4.57V Vout = Vin
• Vin > 4.57V Vout ~ 4.6V

One important thing is that I got Vout(peak-peak) at an high level, for these antique op amp, adding a compensating capacitor between 1 and 8 pin is needed.

From datasheet with Vs=+-15

• common mode min input range = +-14V
• Min output swing = +-13V

So with 0-5V supply, does that mean :

• input range = 1-4V
• output range = 2-3V
  ?
  Why is 600mV measured?

An another op amp http://www.analog.com/media/en/technical-documentation/data-sheets/OP270.pdf, I've these results :

• 0V <= Vin <= 750mV Vout = 0V
• 750mV < Vin <= 5V Vout = Vin + 900mV
  How can I explain results?

After this first experiment, I wired a non inverting amplifier with 2 gain (R1 = R2 = 1k)

• 0V <= Vin <= 600mV \ Vout = 600mV
• 600mV < Vin <= 1.9V Vout = 2 x Vin
• Vin > 1.9V Vout = 3.8V

As in previous setup, op amp not active when Vin <=600mV.
When Vin > 1.9V Vout reaches a max value of 3.8V, why does this value differ from previous setup?

Thanks for your explanations.
lah