I have some ideas but I want to hear more.  I just shot on a mid-blue background.  A very saturated blue.  I shot with one light in various modifiers and positions.  There was glare off the background so I lost some saturation.  Any tips to reduce this and get the true saturated tone of the paper?

move the camera a little to the left or right. Get the sensor plane and background plane to intersect instead of being parallel. The background light would need to be on the same side as the point of interaction of the planes. ie move cam left light should be to your left and right if you move right. Good Luck

Gelling the background light with a color similar to it helps too.  Least any uncontrolled glare will appear much like the background's color.   Makes it richer in color too, imho.

are you over lighting the background? i don't recall having it be glary unless i was using bare bulb (or reflector bowl) or there wasn't any ambient. overblown, though, is easy to do.

you could try bouncing the light, using an umbrella, sheet, a larger modifier, something to make it less glary. when I'm using one background light on the floor to go behind a headshot i often add layers of material to get the edges soft enough.

to evenly light a background some people use two lights, sometimes with large modifiers.

paper kind of sucks, though, because you often wind up with nasty blotchiness noise, creases, etc. sometimes i think muslin wasn't so bad after all.

Thanks a lot guys, I really like the gelled background light idea.  Angles of incidence/reflection, definitely.

The angle of reflectance is equal to the angle of incidence.

If you are getting reflectance, your lights are going to have to move, or the type of light is going to have to change.

As a post workflow item to all the great comments above and aside from the saturation issue, some colors for me are hard to get spot on, even when using the correct white balance.

I use an X-Rite when whatever I'm shooting is color critical. I wouldn't say you need one for all colors or situations though. If you use Lightroom you can build a color profile.

http://xritephoto.com/ph_product_overview.aspx?id=1257

It is really quite simple procedure to have your studio background look black /white or any saturation of color you would desire. (Regardless of the Background ( BG) being a  Gray or White medium  ... be it muslin, paper or wall paint)

To do this you must be able to check and then control the relative difference in the amount of light between your background and subject. You will need to first isolate the background from any (visible spill light that will show up digital or film) .
Once you achieve isolation you can add to the background the correct % of light with or with out a gel to achieve Black ,White or any Color Saturation you desire.  Isolation will happen at just over 3 f stops difference in relative light.
Effectively 3 stops less light (on the BG).. between your shooting aperture -incident flash meter reading (taken at the subject) and a background refelctive flash meter reading  will cause the background to go black (regardless of the background color, either  white or gray )

1st: make certain your back ground is not contaminated by any spill light from your main or kicker lights you have set  to light your subject. Contamination by spill light will wash out richness of you background color and make it impossible to control the ability to obtain  in camera  rich black or dark gray , or to reproduce a  consistent color  saturation any time you shoot  using color gels /filters on your  back ground  lights . 

You do this by setting your subject lights first (no back ground light on) .  Flash Meter for incident  light at your subject ( eg . you meter  f11 ) .
:  Now Change your  Flash Meter to take a reflective  flash reading/ not incident  flash reading 

Pop/Flash your subject  strobe lights again …but this time take a reflective Flash meter reading off of the unlit background.

If you can obtain at least a 3 stop difference (BG minus  3 stops) between  the Flash reflective meter reading of the BG and the  Flash incident meter reading at your subject  …you will have effectively  validated that there will be no visible  contamination by  flash spill light on the BG in the imagery . ( Eg incident subject reading f 11 , reflective background f 4 )

If you want a Black BG.. well you just obtained it with a 3 stop (less) difference in the reflective  flash meter reading taken  off you BG . (  a Gray BG will be black ...White BG  will now be almost black or extreamly dark gray )

If you want White background … add a BG light and get your  reflective  flash meter reading of the  BG to read  plus (+)2-2/3 to (+)3 stops  over your subject incident light  flash meter reading. (NOTE:  if you have previously validated isolation of the BG fromany flash  spill light ) you will not need to be concerned with possiable  background  flash spill/bounce   light( comming off of  the BG )   causing washout/haze from reflective light off of the BG  and on to your subject . A background metered a just over (+) 3 stops (reflective light flash  metered off of the BG) more than  your subject  flash incident  light metered reading  can cause this  haze effect ..which can  also happen if the subject is too close to the BG .( Sometimes this BG spill/haze  is desirable for the image .. it's your choice )

Adding background color and getting whatever color and  saturation to look the same any time you wish (reproduced in any studio)is pretty much done for your  shoot if you have isolated the BG from spill light .  This is a technique perfected and demonstrated by one of the best..Photographer Dean Collins.

His technique required that you first produce/shoot a ONE TIME  TEST Shoot to produce a series of studio test images(to be used as color/saturation..test clips).. taken of  a  Gel lit BG using one BG light illuminating on to a gray or white background.   You would start this shoot.. by adjusting the intensity of Color Gel BG light..using the power adjustment .This BG ( light is positioned at CAMERA position and at least 6 feet from the BG for the test) This BG light is adjusted to get a BG reflective meter reading to match your  lenses mid scale aperture value .  Lets use f 8 (as the lense mid scale f stop )..on a lens (having a range of.. f 2.8 -f 22)

Once this is done you take your first test image with your camera Lense set to its mid scale. ( eg at f 8 )  which will be  called (GEL -0)image and will produce an image of the  BG with a color and saturation very close to the gel color itself( as long as you have no spill light on the BG ...isolated) . You then proceed to shoot a series of images of your BG  using the same  Gelled /Filter BG light ..( at the same power level )  but change the lense f stop /aperture in  incremental one half f stops above +  and one half f stops below - from  your  lens mid aperture value ( eg lens aperture range  f 2.8 -f22)..start your test at f 8 (mid scale )  and dial up and down from there  .

This results in obtaining a set of images (your test clip images for that color)of a BG color with various intensity of saturations..( achieved for the TEST by keeping the light power the same but adjusting the lense F stop to vary the intenisity of color  saturation for each Test Clip image  )..
You can then can  select any of your Test Clip images and  reproduced  that  exact color saturation at any time and at  any studio/location.. by just adjusting you BG  light reflective readings ratio to the subject lights  incident readings as  set  for the  production of that particular test clip image ..

Your test clip of BG saturation color for any particular  Color GEL would be:
(GEL-0) and than  (GEL +1/2) & (GEL -1/2) than (GEL +1) &( GEL -1)  than ( GEL +1-1/2) & ( Gel -1-1/2)  than  (GEL+2) & (GEL -2)  ,( GEL +2 -1/2)  & ( GEL-2 -1/2)

You  just Substitute the actual Filter /Gel idenity eg. (Rosco 342) which is Rose Pink… for GEL term( above )   and you have
(R342-0) (R342+1) , (R342-1 ) ect,

Starting at lens  mid scale aperture/f stop when producing your GEL  test clip prevents you from having to adjust or change the light intensity or  move the BG light distance from the BG  .  This will produce a   more accurate and reproducible set of   color saturation test clip  images that  at any  future time  and with almost any background   can be reproduce in any studio by just  dialing in (adjusting ratio of light difference between Subject and BG to match the ratio shot with your test clip images)the delta F stop  from the (GEL -0 ) value ... will provide you the ability to produce the same saturation of you color test clips.

The color clip tests  images for each of the  color gels   that you have produced can then be used for any of your  shoots to set up your  lighting ratios ..(between the Subject and BG )  to reporduce a  background color saturation  exactly the same as the pre selected test clip color saturation you shot for the Test above .

You  can present your  test clip images to a client for their selection of a BG color/saturation prior to the shoot and know you can product this exact color saturation by keeping  you lighting  ratios  the same as when exposing the selected test clip image during the Test Shoot
( above )  . 

Examples
To obtain a BG with the same color saturation  as the  GEL /Filter .  Make sure the  BG is isolated form spill  and  just meter you BG ( with a reflective flash meter reading )to  achieve the same f stop incident flash  meter reading you read  at your subject. (eg. Subject incident flash  meter reading = f 11 , BG reflective reading needs to be adjusted (via flash  power )  to give a  BG reflective flash reading of  F11  also , ( Shoot with your lense  set at the subjects  incident  light meter reading ( in this ex.
  F 11 ) to obtain the exact  the Test Clip (GEL 0) saturation .

Want a deep vibrant color  for the  BG ( as seen in your (GEL -2 ) test clip image ) than  keep the shooting aperture to that  measured  at the Subject  by the incident  light meter reading ( in this eg. f 11 ), but set your BG  gelled light  power to give reflective light meter reading of  ( in this eg. f 5.6 )  which is  2 stops under the (GEL-0)  saturation  ....( NOTE : this is the same 2 stop reduction  as done during your test clip  production of ( GEL -2) which is an image of a  BG with deep vibrant  saturation  of the gel color ) ..shoot  with the aperture  set to the incident flash  meter reading ( F 11 for this example ).

Want a Light pastel color for the BG as seen in your
( GEL +1/1.2)test clip image.... than set your BG gelled light to give a reflective flash reading of (eg  f 19 ) which is +1-1/2 stop over your subject incident  flash meter reading of ( eg f 11 ) ..Shoot with the aperture set to the incident light  meter reading tmeasured  at  the subject  position (for this example ..at  F 11)

So at any time at any  studio/location with most BG ( regardless of BG  being .. white or gray and in some cases even black ) .. as long as you have isolated the BG from any stray light ,you can produce the exact  BG color saturation , by adjusting the BG  gelled light to give a reflective  light  meter reading F stop value  either ,  above , below or to the same value of shooting aperture ( Lighting F stop measured at  your  subject   with your  incident  light  flash meter .

Look at your test clips images  (determine the BG color saturation you want  your BG to have )and adjust the  ratio of  BG lighting   (as displayed with a  reflective  meter reading ) to your shooting aperture  (determine from incident light reading )of the subject .