Summary (Updated - AF 11/01/2012)

MOPS has reported some peculiar magnitudes in y-band MD data offsets and larger scatter compared to predictions of asteroid y-band magnitudes while the same comparison to 3PI photometry looks reasonable (both cases are photometry from the respective diffims). Also, have found photometry from Warp-Stack (WS) difference images for two sequential MD exposures unrealistically different by >0.5 mag.

Plot of average value for (observed - predicted) magnitudes per night for 3pi and MD detections in y-band.An offset in the MD data making objects ~0.4 mag brighter is seen.

Plot of average value for (observed - predicted) magnitudes per night for 3pi and MD detections in z-band. No offset is seen.

Example: MD10 sequential exposure pair, asteroid (12891) (Peter Vereš)

o6157g0218o
o6157g0219o

ra: 353.142622 
ra: 353.142215

dec:-0.086658
dec: -0.086867

Chip/camera CAL_PSF_MAG photometry from the SMF catalogs below agree to what expected? yes, but can't be more exact because asteroid (12891) previously unstudied.

• o6157g0218o: 17.06
• o6157g0219o: 17.048

camera SMFs:

IPP_IDET  CAL_PSF_MAG  CAL_PSF_MAG_SIG  PSF_INST_MAG  PSF_INST_MAG_SIG  AP_MAG  PSF_MAJOR  PSF_QF_PERFECT  FLAGS  FLAGS2 rsep(")

2384872506.gpc1:MD10.nt:2012:08:18:o6157g0218o.512581:o6157g0218o.512581.cm.524588.smf  XY41
300 17.0643 0.116127 -12.2008  0.0112583 -12.2431 6.2846 0.999136 102760453.0 128.0 0.11619639245

2384878611.gpc1:MD10.nt:2012:08:18:o6157g0219o.512582:o6157g0219o.512582.cm.524591.smf  XY31
353 17.0482 0.119598 -12.2145 0.0109578 -12.2215 6.29196 0.999138 102760453.0 128.0 0.0714361641958

WSdiff CMFs:

IPP_IDET  CAL_PSF_MAG  CAL_PSF_MAG_SIG  PSF_INST_MAG  PSF_INST_MAG_SIG  AP_MAG  PSF_MAJOR  PSF_QF_PERFECT  FLAGS  FLAGS2  DIFF_NRATIO_BAD  rsep (")

2385003229.gpc1:MD10.nightlyscience:2012:08:18:MD10.V3:skycell.052:MD10.V3.skycell.052.WS.dif.272923.cmf
180 17.1593 0.0 -12.1058 0.0549115 -12.0586 6.91519 0.999313 35651585.0 2177.0 0.586518 0.00506595268768

2385006586.gpc1:MD10.nightlyscience:2012:08:18:MD10.V3:skycell.052:MD10.V3.skycell.052.WS.dif.272924.cmf
143 16.5429 0.0 -12.7198 0.0508926 -12.0717 10.5122 0.998732 35651585.0 129.0 0.614977 0.00257287140

Manually rerunning WSdiffims with current ipp-20121026 tag (conv + unconv refstack):

Manually rerunning WSdiffims with tag ipp-20110622 that was active when photometry looked better last year (see example mag plot for TNO145452 below):

Example: MD09, TNO145452 (Alan Fitzsimmons)

TNO 145452

• a bit faint but its' the best one I've found so far, as it stays in the field for a long long time.
• in MD09 where we can predict the y magnitude should be within 0.1 mag of ~19.3 for the below observations
• a bunch of y-band exposures in 2011 and 2012.
• columns are Exp ID, MJD, RA, Dec.

  2011:
  o5756g0570o  55756.592040       333.326857   +0.597387    
  o5756g0571o  55756.595015       333.326815   +0.597377    
  o5756g0572o  55756.597969       333.326774   +0.597368    
  o5756g0573o  55756.600918       333.326733   +0.597359    
  o5756g0574o  55756.603875       333.326692   +0.597350    
  o5756g0576o  55756.609792       333.326609   +0.597332    
  o5756g0577o  55756.612748       333.326568   +0.597323    
  o5757g0356o  55757.496424       333.314491   +0.594541    
  o5757g0357o  55757.499384       333.314449   +0.594532    
  o5757g0358o  55757.502357       333.314407   +0.594522    
  o5757g0359o  55757.505335       333.314365   +0.594513    
  o5757g0360o  55757.508292       333.314323   +0.594503    
  o5757g0361o  55757.511248       333.314281   +0.594494    
  o5757g0362o  55757.514208       333.314239   +0.594484    
  o5757g0363o  55757.517163       333.314197   +0.594475    
  o5766g0299o  55766.477073       333.180973   +0.559502    
  o5784g0173o  55784.507883       332.868350   +0.454736    
  o5784g0174o  55784.510828       332.868295   +0.454715    
  o5784g0175o  55784.513776       332.868239   +0.454695    
  o5784g0176o  55784.516717       332.868184   +0.454674    
  o5784g0177o  55784.519667       332.868128   +0.454654    
  o5784g0178o  55784.522608       332.868073   +0.454633    
  o5784g0180o  55784.528498       332.867962   +0.454592    
  (ending at 08-11-2011)
  
  2012: (starting 06-29-2012)
  o6107g0064o  56107.597172       334.910525   +0.746688    
  o6107g0065o  56107.600110       334.910498   +0.746686    
  o6107g0066o  56107.603062       334.910470   +0.746684    
  o6107g0067o  56107.606006       334.910442   +0.746681    
  o6107g0068o  56107.608993       334.910414   +0.746679    
  o6201g0056o  56201.242691       333.383584   +0.125386    
  o6201g0057o  56201.245657       333.383540   +0.125358    
  o6201g0058o  56201.248616       333.383497   +0.125330    
  
  

This is the best example in the database because of the density of measurements and the known small amplitude of any lightcurve. In warp-warp diffs the slow motion will mean that 3PI and OSS measurements would be incorrect due to self-subtraction of the flux. But this should not only occur in MD fields as MOPS is being fed warp-stack measurements, and it would make the object fainter not brighter as seen. The variation in z-band and in other filters in 2012 is also puzzling.

Plot of observed magnitudes converted to V (top), and residual of magnitude (observed - predicted), in 2011 and 2012: (Key: g=green, r=red,i=orange,z=purple,y=cyan)

camera SMFs: both the original nightly processing and MD.GR0 reprocessing

Filename  IPP_IDET  CAL_PSF_MAG  CAL_PSF_MAG_SIG  PSF_INST_MAG  PSF_INST_MAG_SIG  AP_MAG  PSF_MAJOR  PSF_QF_PERFECT  FLAGS  FLAGS2  rsep  chipXY
allsmf_y/1091859485.gpc1:MD09.nt:2011:07:14:o5756g0570o.361984:o5756g0570o.361984.cm.233853.smf 1006 19.542 0.0110485 -9.8774 0.0530022 -9.76364 1.98885 0.999665 35651585.0 128.0 0.293673968137  XY13
allsmf_y/1091858911.gpc1:MD09.nt:2011:07:14:o5756g0571o.361983:o5756g0571o.361983.cm.233852.smf 1542 19.3076 0.0078125 -10.1154 0.0374652 -10.4434 1.99539 0.999581 102760453.0 128.0 0.314257455367  XY14
allsmf_y/1091937189.gpc1:MD09.nt:2011:07:14:o5756g0572o.361986:o5756g0572o.361986.cm.233864.smf 2746 19.1615 0.0002 -10.2693 0.0390398 -11.1417 2.81364 0.999328 35667969.0 128.0 0.371845974752  XY14
allsmf_y/1091890096.gpc1:MD09.nt:2011:07:14:o5756g0573o.361985:o5756g0573o.361985.cm.233854.smf 831 19.3682 0.0002 -10.0494 0.0408918 -10.0925 1.77422 0.998278 35651585.0 128.0 0.263690103858  XY15
allsmf_y/1091937005.gpc1:MD09.nt:2011:07:14:o5756g0574o.361988:o5756g0574o.361988.cm.233861.smf 890 19.2714 0.0002 -10.1357 0.0334194 -10.241 1.58012 0.997229 102760517.0 128.0 0.288420964073   XY25
allsmf_y/1092057932.gpc1:MD09.nt:2011:07:14:o5756g0576o.361989:o5756g0576o.361989.cm.233862.smf 741 19.2317 0.0002 -10.1715 0.0313833 -10.2889 1.4934 0.998446 102776839.0 128.0 0.323207890476  XY36
allsmf_y/1091915330.gpc1:MD09.nt:2011:07:14:o5756g0577o.361991:o5756g0577o.361991.cm.233856.smf 714 19.2255 0.0110485 -10.1885 0.0352801 -10.2399 1.70252 0.997404 102760453.0 128.0 0.248178473752  XY36

allsmf_y/1094681457.gpc1:MD09.nt:2011:07:15:o5757g0356o.362440:o5757g0356o.362440.cm.234103.smf 709 19.2994 0.0135316 -10.0261 0.0356414 -10.0953 1.69949 0.997154 102760453.0 128.0 0.25274423932  XY26
allsmf_y/1094682661.gpc1:MD09.nt:2011:07:15:o5757g0357o.362439:o5757g0357o.362439.cm.234105.smf 825 19.2792 0.0002 -10.032 0.032561 -10.0684 1.6093 0.998073 102760453.0 128.0 0.245336062809  XY36
allsmf_y/1094757324.gpc1:MD09.nt:2011:07:15:o5757g0358o.362441:o5757g0358o.362441.cm.234104.smf 783 19.3713 0.0002 -9.92562 0.0326609 -9.89588 1.50272 0.996934 102760517.0 128.0 0.288074111793  XY36
allsmf_y/1096254860.gpc1:MD09.nt:2011:07:15:o5757g0359o.362442:o5757g0359o.362442.cm.234355.smf 755 19.2394 0.0135316 -10.0597 0.0259816 -10.1772 1.24991 0.997579 102776839.0 128.0 0.266072048882  XY46
allsmf_y/1094702845.gpc1:MD09.nt:2011:07:15:o5757g0360o.362443:o5757g0360o.362443.cm.234106.smf 760 19.2922 0.0110485 -10.0048 0.0269262 -10.0441 1.32307 0.997986 102760517.0 128.0 0.164755072606  XY56
allsmf_y/1094717069.gpc1:MD09.nt:2011:07:15:o5757g0361o.362444:o5757g0361o.362444.cm.234108.smf 763 19.2601 0.0110485 -10.041 0.0251754 -10.0456 1.15059 0.61201 102760453.0 160.0 0.234971157935  XY55
allsmf_y/1094852307.gpc1:MD09.nt:2011:07:15:o5757g0362o.362445:o5757g0362o.362445.cm.234107.smf 778 19.3239 0.0002 -9.98648 0.0274614 -10.0391 1.29515 0.998163 102760517.0 128.0 0.244265226696  XY65
allsmf_y/1094715184.gpc1:MD09.nt:2011:07:15:o5757g0363o.362447:o5757g0363o.362447.cm.234110.smf 1119 19.2728 0.0002 -10.0418 0.0289349 -9.92657 1.42937 0.942766 35667969.0 128.0 0.318406989301  XY65

allsmf_y/1128179911.gpc1:MD09.nt:2011:07:24:o5766g0299o.367502:o5766g0299o.367502.cm.239536.smf 638 19.1963 0.0135316 -9.31779 0.0570201 -9.74115 1.23697 0.998962 35667969.0 128.0 0.307523431054  XY66

allsmf_y/1177140372.gpc1:MD09.nt:2011:08:11:o5784g0173o.374858:o5784g0173o.374858.cm.246059.smf 709 19.2016 0.0110485 -10.1995 0.0363701 -10.2381 2.10216 0.998289 102760453.0 128.0 0.287671937631  XY02
allsmf_y/1177146799.gpc1:MD09.nt:2011:08:11:o5784g0174o.374859:o5784g0174o.374859.cm.246060.smf 735 19.111 0.0002 -10.2709 0.0314764 -10.3194 1.92565 0.999441 102760453.0 128.0 0.306010382339  XY03
allsmf_y/1177195723.gpc1:MD09.nt:2011:08:11:o5784g0175o.374860:o5784g0175o.374860.cm.246063.smf 727 19.2234 0.0078125 -10.1564 0.0313712 -10.1613 1.71819 0.997556 102760453.0 128.0 0.345360221669  XY04
allsmf_y/1177158950.gpc1:MD09.nt:2011:08:11:o5784g0176o.374861:o5784g0176o.374861.cm.246064.smf 549 19.2348 0.0002 -10.1287 0.0292558 -10.1269 1.59032 0.997811 102760453.0 128.0 0.31644730333  XY05
allsmf_y/1177171394.gpc1:MD09.nt:2011:08:11:o5784g0177o.374862:o5784g0177o.374862.cm.246065.smf 597 19.2512 0.0002 -10.1147 0.0297026 -10.0878 1.56931 0.997511 102760517.0 128.0 0.316947579793  XY05
allsmf_y/1177178772.gpc1:MD09.nt:2011:08:11:o5784g0178o.374863:o5784g0178o.374863.cm.246066.smf 673 19.1859 0.0002 -10.1801 0.0290253 -10.2592 1.62494 0.998467 102760517.0 128.0 0.340535659701  XY16
allsmf_y/1177199195.gpc1:MD09.nt:2011:08:11:o5784g0180o.374865:o5784g0180o.374865.cm.246068.smf 698 19.3226 0.015625 -10.056 0.0332161 -9.87659 1.72053 0.905537 102760517.0 128.0 0.289871260978  XY27

--> MD.GR0 reprocessed set
allsmf_y/2119523678.gpc1:MD09.GR0.20120601:o5756g0570o.361984:o5756g0570o.361984.cm.444636.smf 927 19.4031 0.0347004 -9.86899 0.0538396 -9.55621 3.07128 0.998451 35651585.0 0.0 0.165656661564  XY13
allsmf_y/2119525130.gpc1:MD09.GR0.20120601:o5756g0571o.361983:o5756g0571o.361983.cm.444635.smf 1430 19.1508 0.038065 -10.1206 0.0415301 -9.94855 2.99097 0.984204 35651585.0 128.0 0.284367855279  XY14
allsmf_y/2119526275.gpc1:MD09.GR0.20120601:o5756g0573o.361985:o5756g0573o.361985.cm.444637.smf 774 19.1714 0.035183 -10.0966 0.0394413 -10.2147 2.66831 0.997528 35651585.0 128.0 0.288090212979  XY15
allsmf_y/2119527511.gpc1:MD09.GR0.20120601:o5756g0572o.361986:o5756g0572o.361986.cm.444638.smf 2385 19.5544 0.0375786 -9.72273 0.0551657 -9.78636 4.13405 0.997439 35651585.0 0.0 0.280385865677  XY14
allsmf_y/2119528877.gpc1:MD09.GR0.20120601:o5756g0574o.361988:o5756g0574o.361988.cm.444640.smf 838 19.1213 0.034996 -10.1347 0.0334182 -10.2115 2.31725 0.997083 102760453.0 128.0 0.313508781254  XY25
allsmf_y/2119536441.gpc1:MD09.GR0.20120601:o5756g0576o.361989:o5756g0576o.361989.cm.444641.smf 706 19.0464 0.0353012 -10.2066 0.0308417 -10.3525 2.18759 0.996929 35667969.0 128.0 0.295050323865  XY36
allsmf_y/2119539963.gpc1:MD09.GR0.20120601:o5756g0577o.361991:o5756g0577o.361991.cm.444642.smf 680 19.0725 0.0340767 -10.1915 0.0349833 -10.233 2.50036 0.997369 102760453.0 128.0 0.248942934636  XY36

allsmf_y/2119541070.gpc1:MD09.GR0.20120601:o5757g0357o.362439:o5757g0357o.362439.cm.444643.smf 771 19.105 0.0374031 -10.0554 0.0325219 -10.0717 2.38192 0.997699 102760453.0 128.0 0.232213567681  XY36
allsmf_y/2119543361.gpc1:MD09.GR0.20120601:o5757g0356o.362440:o5757g0356o.362440.cm.444644.smf 684 19.1361 0.0362549 -10.0374 0.0357374 -10.074 2.59938 0.996931 102760453.0 128.0 0.24786495319  XY26
allsmf_y/2119550643.gpc1:MD09.GR0.20120601:o5757g0358o.362441:o5757g0358o.362441.cm.444645.smf 729 19.1801 0.0416241 -9.96211 0.0319122 -9.96096 2.25018 0.9968 102760453.0 128.0 0.258901554458  XY36
allsmf_y/2119551751.gpc1:MD09.GR0.20120601:o5757g0359o.362442:o5757g0359o.362442.cm.444646.smf 763 19.0927 0.0452118 -10.0447 0.0263285 -10.1168 1.83759 0.997848 102760453.0 128.0 0.263023433516  XY46
allsmf_y/2119554727.gpc1:MD09.GR0.20120601:o5757g0361o.362444:o5757g0361o.362444.cm.444648.smf 721 19.1048 0.0410404 -10.0359 0.0252832 -10.0375 1.67282 0.609012 102760453.0 160.0 0.259161110867  XY55
allsmf_y/2119558442.gpc1:MD09.GR0.20120601:o5757g0363o.362447:o5757g0363o.362447.cm.444650.smf 972 19.1128 0.0390358 -10.0465 0.0291075 -9.93286 2.14288 0.939545 102760453.0 128.0 0.28588415797  XY65
allsmf_y/2119560202.gpc1:MD09.GR0.20120601:o5757g0362o.362445:o5757g0362o.362445.cm.444649.smf 734 19.1359 0.0399323 -10.0151 0.0273009 -10.0644 1.94851 0.998377 102760517.0 128.0 0.228009708514  XY65
allsmf_y/2119564253.gpc1:MD09.GR0.20120601:o5757g0360o.362443:o5757g0360o.362443.cm.444651.smf 736 19.1421 0.0432816 -9.99417 0.0273164 -10.0274 2.12572 0.997947 102760453.0 128.0 0.208110361929  XY56

allsmf_y/2119575990.gpc1:MD09.GR0.20120601:o5766g0299o.367502:o5766g0299o.367502.cm.444658.smf 609 19.0219 0.0593719 -9.32562 0.0569102 -9.71989 1.86014 0.998937 35667969.0 0.0 0.251615274957  XY66

allsmf_y/2119581769.gpc1:MD09.GR0.20120601:o5784g0173o.374858:o5784g0173o.374858.cm.444664.smf 624 18.9922 0.0346775 -10.2556 0.0363824 -10.1999 3.2577 0.998072 102760453.0 128.0 0.229506615049  XY02
allsmf_y/2119581016.gpc1:MD09.GR0.20120601:o5784g0174o.374859:o5784g0174o.374859.cm.444665.smf 684 18.9532 0.0334682 -10.2746 0.0314982 -10.2982 2.88943 0.999431 102760453.0 128.0 0.250330896722  XY03
allsmf_y/2119581238.gpc1:MD09.GR0.20120601:o5784g0175o.374860:o5784g0175o.374860.cm.444666.smf 696 19.0781 0.0355721 -10.1465 0.0314575 -10.121 2.50819 0.997477 102760453.0 128.0 0.306669022584  XY04
allsmf_y/2119587747.gpc1:MD09.GR0.20120601:o5784g0176o.374861:o5784g0176o.374861.cm.444667.smf 518 19.0588 0.035244 -10.1525 0.0288681 -10.1593 2.36462 0.997416 102760453.0 128.0 0.253292782686  XY05
allsmf_y/2119589883.gpc1:MD09.GR0.20120601:o5784g0177o.374862:o5784g0177o.374862.cm.444668.smf 557 19.1038 0.0358238 -10.1062 0.0294136 -10.1214 2.49456 0.996401 102760453.0 128.0 0.266726320282  XY05
allsmf_y/2119590278.gpc1:MD09.GR0.20120601:o5784g0178o.374863:o5784g0178o.374863.cm.444669.smf 624 19.0648 0.0336094 -10.1493 0.0295484 -10.1969 2.47266 0.998443 102760453.0 128.0 0.265379521295  XY16
allsmf_y/2119589969.gpc1:MD09.GR0.20120601:o5784g0180o.374865:o5784g0180o.374865.cm.444670.smf 641 19.1304 0.0336227 -10.0956 0.0323633 -9.94459 2.51228 0.901043 102760453.0 128.0 0.26594163544  XY27

--> 2012
allsmf_y/2152846158.gpc1:MD09.nt:2012:06:29:o6107g0064o.500972:o6107g0064o.500972.cm.452770.smf 621 19.1367 0.0380592 -10.1031 0.0370403 -10.1191 3.64526 0.998268 102760453.0 128.0 0.359944800142  XY64
allsmf_y/2152850545.gpc1:MD09.nt:2012:06:29:o6107g0065o.500973:o6107g0065o.500973.cm.452771.smf 751 19.2627 0.0403404 -9.97675 0.0419588 -9.58391 3.64146 0.998282 35651585.0 128.0 0.301132671017  XY64
allsmf_y/2152853156.gpc1:MD09.nt:2012:06:29:o6107g0066o.500974:o6107g0066o.500974.cm.452772.smf 687 19.0854 0.0341835 -10.1473 0.0332613 -10.2999 3.27303 0.999091 35667969.0 128.0 0.353007422374  XY63
allsmf_y/2152855541.gpc1:MD09.nt:2012:06:29:o6107g0067o.500975:o6107g0067o.500975.cm.452773.smf 802 19.239 0.0348358 -9.9948 0.0388879 -9.81758 3.35322 0.998988 102760517.0 128.0 0.332366946945  XY63
allsmf_y/2152858750.gpc1:MD09.nt:2012:06:29:o6107g0068o.500976:o6107g0068o.500976.cm.452774.smf 683 19.285 0.0372105 -9.94822 0.0425646 -9.94024 3.40356 0.998062 35651585.0 128.0 0.315394196097  XY62

allsmf_y/2619124827.gpc1:MD09.nt:2012:10:01:o6201g0056o.524345:o6201g0056o.524345.cm.593200.smf 705 19.1161 0.0432129 -9.86222 0.0551932 -9.60648 2.50001 0.997367 35651585.0 0.0 0.241774089381  XY55
allsmf_y/2619134453.gpc1:MD09.nt:2012:10:01:o6201g0057o.524346:o6201g0057o.524346.cm.593201.smf 785 19.0833 0.0387001 -10.0648 0.0383378 -10.2246 2.44958 0.998246 102760453.0 128.0 0.303037238582  XY55
allsmf_y/2619131479.gpc1:MD09.nt:2012:10:01:o6201g0058o.524347:o6201g0058o.524347.cm.593203.smf 808 19.2722 0.036787 -9.86303 0.0457602 -9.77779 2.57769 0.997363 35651585.0 128.0 0.320983517002  XY55

Example: MD01, MBA 131130 (Alan Fitzsimmons)

This is a nice example of the offset plus large scatter in y-band for a Main Belt Asteroid seen this year.

o6169g0184o 36.353429    -4.350323    
o6169g0185o 36.353441    -4.350616    
o6170g0586o 36.360948    -4.446235    
o6170g0588o 36.360938    -4.446831    
o6170g0590o 36.360927    -4.447427    
o6170g0591o 36.360922    -4.447725    
o6170g0593o 36.360911    -4.448320    
o6171g0613o 36.362699    -4.549196    
o6171g0614o 36.362676    -4.549499    
o6171g0616o 36.362631    -4.550103    
o6171g0617o 36.362608    -4.550406    
o6171g0619o 36.362562    -4.551012    
o6172g0677o 36.358383    -4.654112    
o6172g0682o 36.358181    -4.655647    
o6172g0683o 36.358141    -4.655956    
o6172g0684o 36.358101    -4.656264    

Plot of observed magnitudes converted to V (top), and residual of magnitude (observed - predicted) in 2012. The large gap in the data was caused by telescope shutdown due to rotator problems. (Key: g=green, r=red,i=orange,z=purple,y=cyan)