I've spent a lot of time trying to find an easy "how-to" on understanding the peaks you get from an absorbance vs wavelength graph with multiple samples.

1) I saw on a youtube video that the width of the peak corresponds to polydispersity- is this true? 2) I read that the ideal absorbance range is between 0-2. Anything above that "is not accurate". Does that mean these samples should be diluted more even though I got a reading (with no errors)? Some of them have values up to 4.

3) What does it mean when there are two peaks for one sample? Some of my more concentrated solutions have one large peak and a smaller "bump". Does this mean the reading was inaccurate?

I've attached my graph to this post. For background, I did a serial dilution of yellow and red food dye with water to mimic different blood serum colors.

Thank you all so much!