The left frames are cropped with a positive starting x (as specified in the list) 
and with a width of 4000 pixels - this will mostly be the 4000 rightmost pixels in 
the image. 
Similarly the right frames are cropped in such a way that they end up being 4000 
pixels wide and contain the leftmost pixels in the image - from pixel 0 to 3999
always.
Both left and right frames always use the entire height of 2250 pixels.
Scenes with multiple render attempts or additional viewing angles will have more
than just two folderIDs in the list.

Here is the list of (inclusive) cropping pixel values for the left frames:
Scene	Left	Folder IDs (Left,Right)
00_00	55	(1772)
01_01	40	(1114,1115)(1245)
01_02	63	(1119,1120)(1137)(1128)(1127)
01_03	73	(1214,1215)(1202)(1126)
01_04	19	(1121,1122)
02_01	109	(1173,1174)
02_02	54	(1171,1172)
02_03	52	(1192,1193)
02_04	162	(1175,1176)
02_05	70	(1177,1178)
02_06	87	(1179,1180)
02_07	80	(1445,1446)
03_01	70	(1208,1209)
03_02	72	(1210,1211)
03_03	7	(1129,1130)
03_05	77	(1449,1450)
03_06	79	(1212,1213)
03_07	44	(1315,1316)
03_08	78	(1337,1338)
04_01	50	(1307,1308)
04_02	71	(1309,1310)
04_03	50	(1194,1195)
05_01	84	(1218,1219)(1196,1197)
05_02	64	(1198,1199)(1774,1775)
05_03	48	(1187,1188)
05_04	64	(1205,1206)
05_05	83	(1225,1226)
05_06	64	(1321,1322)
05_07	83	(1231,1232)
05_08	64	(1323,1324)(1742,1743)
05_09	83	(1227,1228)
05_10	64	(1325,1326)
05_11	61	(1334,1335)
05_12	64	(1327,1328)
06_01	112	(1460,1461)(1233,1234)
06_02	54	(1258,1259)
06_04	63	(1251,1252)
06_05	118	(1319,1320)
06_07	96	(1260,1261)
06_08	71	(1330,1331)
06_09	96	(1265,1266)
06_11	96	(1437,1438)(1744,1745)(1746,1747)(1748,1749)
06_12	91	(1267,1268)
06_13	96	(1439,1440)
06_14	67	(1249,1250)
06_15	54	(1305,1306)
07_01	35	(1313,1314)
07_02	89	(1317,1318)
07_03	55	(1424,1425)
07_05	93	(1332,1333)
07_06	35	(1247,1248)
08_01	66	(1269,1270)
08_02A	40	(1426,1427)
08_02B	84	(1428,1429)
08_03	43	(1271,1272)
08_04	64	(1273,1274)
08_05	99	(1275,1276)
08_11A	104	(1288,1289)
08_11B	46	(1311,1312)
08_07A	100	(1399,1400)
08_07B	82	(1277,1278)
08_08	78	(1146,1147)
08_09	81	(1490,1491)(1416)(1279)
08_10	53	(1290,1291)
08_12	76	(1131,1132)
08_13	62	(1339,1340)
08_14	62	(1341,1342)
08_19	72	(1401,1402)
08_15	64	(1343,1344)
08_16	28	(1345,1346)
08_17	7	(1133,1134)
08_18	39	(1347,1348)
09_01	56	(1349,1350)
09_02	70	(1351,1352)
09_03	95	(1776,1777)(1441,1442)
09_04	113	(1355,1356)
09_05	227	(1392,1393)
09_06	122	(1353,1354)
09_07	149	(1397,1398)
09_08	86	(1417,1418)
09_09	122	(1453,1454)(1374,1375)
09_10	187	(1376,1377)
09_13	128	(1378,1379)(1750,1751)
10_02	39	(1435,1436)(1754,1755)(1759,1760)(1761,1762)(1763,1764)(1765,1766)
10_03	13	(1141,1142)
11_01	133	(1403,1404)
11_02	107	(1368,1369)
11_03	92	(1380,1381)
11_04	26	(1382,1383)
11_05	313	(1384,1385)
11_06	73	(1422,1423)
11_07	71	(1386,1387)
11_08	93	(1388,1389)
11_09	65	(1405,1406)
11_10	76	(1390,1391)
11_11	53	(1165,1166)
12_01	83	(1407,1408)
12_02	96	(1457,1458)
12_03	134	(1443,1444)
12_04	51	(1135,1136)
12_05	36	(1420)(1190,1191)
12_06	43	(1169,1170)
12_07	57	(1432,1430)(1216)
12_08	50	(1167,1168)
12_09	11	(1409,1410)
12_10	123	(1433,1434)
12_12	50	(1476,1569)(1473)
12_14	36	(1149,1150)
12_15	69	(1163,1164)
12_16	29	(1161,1162)
12_17	30	(1143,1144)
12_20	93	(1455,1456)
12_21A	87	(1451,1452)(1769,1770)
12_21B	86	(1447,1448)
13_01	20	(1155,1154)
13_02	40	(1152,1153)
13_03	105	(1411,1412)
13_04	98	(1469,1470)(1838,1839)
13_05	40	(1156,1157)
13_06	75	(1159,1160)
13_07	29	(1413,1414)
13_09	118	(1242,1243)
13_10	48	(1661)

Additional information about each folder can be found by searching for
the session ID on the BURP renderfarm.