I am using a Spyder3 for my first foray into creating my own profiles. I am working with Red River Photo Matte and have discovered that the profile for the 8.5x11 is different from the 13x19. Is it me, the brand of paper or is it normal for different boxes of the same paper to have a different profile?

I assume that you built two profiles for two different formats. If you build profiles from different set of measurements they will be different even if you use the same paper (size, stock). Moreover if you re-measure the same printed target you will get different numbers and consequently different profiles. The accuracy of a measurement device and spatial variations (non-uniformity of color patches in the printed target) are common reason for that.

It would be useful to know how different is "different"? Do you have a means to calculate a deltaE difference between one measurement and the other?
The MeasureTool program in the ProfileMaker suite of tools allows you to compare 2 measurement sets for average and maximum delta E's (and does not require a dongle.) Maxwell is an online service that allows you to upload measurements and make comparisons like this.
www.mxwell.com

Assuming you're comparing two of your own profiles there are a lot of things that can result in differences on the same paper. Just a few examples:
1) Drying time. VERY important. inks and glossiness change a LOT in the first few hours. Not so much after 24 hours.
2) Driver settings. If you messed up one single setting between separate profile chart prints then the profiles will be very different.
3) Ink particle settling. Really old inks may have the particles settle and might be able to use some agitation.
4) Patch counts. I can print 2900 some patches on a 24"x8.5" strip off a roll on my 7800 whereas I can only get 1054 patches onto a single 8.5x11 sheet fed. The profiles are very different there. (I use an i1 isis / PM5 btw)

Another difference worth special mention for certain papers is that some large roll papers are not made exactly the same way as their smaller sheet counterparts. Sometimes for practical reasons like needing the small sheets to lay flatter or needing the roll papers to unroll reasonably well. Its usually pretty obvious because the gsm's tend to be different.

Anyway, think of making profiles as being like casting a magical spell. you MUST do everything the same every time. Some differences are more reasonable than others. For example the difference between waiting 10 minutes for drying and 1 hour before drying is IMMENSE. But the difference in waiting 24 hours for drying and 4 days for drying is negligible.

xilvar

The difference is quite noticeable by eye. I measured some random squares and found differences, but I have no idea how much of a difference using a LAB scale is significant.

I have had experience with this in a slightly different manner, when a profile was made for a particular paper, and there were differences in the printing after I changed rolls after one roll had run out. . I thought I must have forgotten something so I reprinted, then found a scrap from the previous roll and reprinted again. Sure enough there were marked differences.

Knowing that some paper companies have various manufacturing mills around the world, even though all using the same 'recipe', there are bound to be differences between rolls produced from different mills branded under the one label.

I wouldn't be surprised if the different sized media and differnt results in your profile are a result of the same branded 'flavour' paper has been produced in a different location.


Julie

Then something is wrong. To answer your original question, it is not normal for there to be significant color changes within paper of the same type.

There have already been some good hints in this thread as to why this could be happening in your case. I'll just add that in our experience, 90% of the time a change is seen in a profile, it ends up being due to something changing in the profile creation process. Like Xilvar said, be consistent. Then again, it could be something obscure: Is one of the papers a lot older than the other? Red River Photo Matte will have some optical brighteners in it, and if the paper is old, it won't "fluoresce" like a newer paper does.
http://www.colorwiki.com/wiki/Optical_Brighteners_in_Paper