Select Multiple Values in Where Time Clause Equals
===

My table looks like this:

Table 1:
Note: This table is very large in reality, with lots more columns (20ish) and rows (in the millions)


     |  Time      |  tmp   |  productionID  |
     |  10:00:00  |   2.2  |    5           |
     |  10:00:05  |   5.2  |    5           |
     |  10:00:11  |   7.4  |    5           |
     |  ......    |   3.2  |    5           |
     |  10:10:02  |   4.5  |    5           |

 Note: Timeis a varchar, so I assume I need to do something like this:
       
     CONVERT(VARCHAR(8), DATEADD(mi, 10, time), 114)

What I need to do is:

     select time, tmp 
     from mytable
     where productionid = somevalue 
     and time = first_time_stamp associated to some productionID(ie. 10:00:00 table above)
         time = 10 minutes after the first_time_stamp with some productionID
         time = 20 minutes after the first_time_stamp with some productionID
         ...25, 30, 40, 60,	120, 180 minutes 

I hope this  makes sense.  I'm not sure what the right way to do this is.  I mean I thought of the following proccess:
-select first time stamp (with some productionID)
-add 10 minutes to that that time, 
-add 20 minutes etc.. then use a pivot table and use joins to link to table 1
There must be an easier way.

Thank you in advance for the expertise.