NIRC Filter Fluxes
Following are mean values for frames taken through each of the 400 possible inner/outer filter wheel combinations. These are 1 second exposures using patslow. No bias has been remved, so that zero flux corresponds to ~23,000 DN. Also, the detector was partially affected by the "flashlight effect," in which optical light has depressed the sensitivity somewhat over a small portion of the field. Also note that the red values of 23,000 are placeholders for cases in which the IDl routine did not report a mean.

The range of uncertainty can be estimated by looking at the first row, which has an aluminum plug in the inner filter wheel, hence should be the equivalent of a bias frame.

Finally, be aware that if one or both filter wheels is not setting correctly, there may be significant vignetting of the field, meaning either that not as much flux will be passed by the filters, or possibly that the flux will represent a combination of flux from two adjacent filters, combined with the vignetting.

  fwo 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
fwi   hei pgamma oii pbeta feii bracont bralpha gr150 gr120 gr60 uv22o h210 brgamma h221 co20 kcont pahcs pah pahl open
0 cold plug 23205 23197 23199 23198 23199 23200 23208 23210 23211 23208 23213 23143 23138 23139 23135 23142 23140 23143 23150 23137
1 jh 23208 23201 23194 23195 23200 23193 23213 23215 23232 23488 23187 23146 23136 23138 23140 23139 23144 23163 23153 23635
2 z 23201 23200 23197 23199 23201 23200 23203 23207 23209 23205 23168 23141 23138 23134 23139 23139 23000 23139 23142 23141
3 jh 23202 23196 23199 23197 23202 23213 23208 23399 23385 28956 23211 23142 23138 23133 23139 23140 23143 23139 23139 23000
4 h 23209 23198 23197 23196 23199 23210 23203 23300 23293 25732 23174 23141 23139 23139 23135 23140 23148 23142 23147 30462
5 ch4 23203 23196 23193 23195 23201 23207 23232 24223 24969 25531 25064 23136 23152 23284 23409 23611 23135 23139 23134 26561
6 kp 23203 23200 23198 23194 23206 23196 23205 23746 23000 24291 24422 23170 23201 23239 23229 23429 23138 23132 23137 24676
7 ks 23205 23196 23196 23198 23203 23197 23206 23793 24333 23000 24583 23167 23197 23246 23319 23478 23137 23000 23131 24886
8 k 23200 23197 23196 23201 23199 23192 23211 24667 26344 26618 27435 23169 23211 23245 23382 23518 23140 23137 23156 28516
9 hk 23200 23194 23198 23199 23197 23195 23207 25557 28699 29185 31123 23174 23205 23258 23352 23516 23138 23134 23137 33298
10 kw 23199 23199 23196 23196 23199 23199 23210 26407 30652 31666 23000 23171 23206 23279 23391 23585 23141 23150 23137 38130
11 uv22i 23191 23202 23198 23197 23201 23195 23205 27728 36368 38951 44258 23169 23199 23246 23330 23475 23139 23138 23141 53467
12 ls 23200 23208 23202 23248 23200 23225 23228 48951 59378 65457 63066 23138 23136 23140 23136 23140 63402 23000 63637 64768
13 lp 23197 23227 23198 23206 23212 64928 64991 23000 65498 65534 34695 23139 23135 23136 23138 23139 23216 23000 30484 65533
14 kl 23198 23229 23201 23265 23208 64766 64857 65494 65509 65534 63192 23153 23200 23265 23402 23586 63389 63432 63627 65532
15 lw 23193 23232 23205 23255 23203 64869 23000 23000 65510 65534 51365 23137 23142 23139 23141 23136 63416 23000 63690 65531
16 m 23193 23213 23198 23199 23197 24159 25184 65528 65526 65523 63367 23139 23140 23137 23141 23146 23186 23139 23138 65482
17 lm 23195 23259 23199 23216 23204 64828 64946 65529 65530 65535 63317 23142 23137 23135 23138 23141 63452 63480 63679 65485
18 mw 23194 23218 23202 23196 23203 23991 24746 65532 65532 65528 63441 23140 23143 23138 23142 23143 23185 23151 23145 65507
19 open 23196 23268 23200 23277 23204 64769 64932 65533 65533 65535 63537 23182 23220 23301 23448 23667 23000 63455 63651 65512

Chart Mean Flux from Various Filter Combinations

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