Sample Galaxies

  • 144 galaxies were selected with size in the range 0 and 2 arcmin. The size distribution is chosen to be uniform.
  • The photometry results for both SDSS and Pan-STARRS are displayed in the below table. (please scroll down)
  • To make a better comparisons, all of those galaxies with noisy images, or bad data were removed. 19 galaxies were then removed. These information and the results for these galaxies are available on the below table. These galaxies are PGC [40761,23519,64552,62651,60049,24469,90968,61254,4010299,38457,142843,91191,39833,48409,1672298,1305231,61220,60436,53891].
  • After removing these galaxies, we are left with 125 galaxies.
  • The comparison between SDSS and Pan-STARRS photometry results. In most cases it's obvious that Pan-STARRS photometry turns out fainter magnitudes. It's due to the background oversubtraction, and unfortunately this does not depend on the size of the galaxy.


  • The same plots for r-band


  • This plot compare g-r colors in terms of size. No correlation with galaxy size is apparent. The color discrepancy is roughly around 0.1 mag. Since SDSS photometry accuracy is around 0.05 mag at best (color accuracy of ~0.07), then this plot indicates a color accuracy of about 0.15 mag at best.
  • Also one has to note that out of 144 galaxies 19 (13%) have been removed due to data quality (mostly Pan-STARRS).


  • This shows the g-band image of PGC90968 (RA:149.70750 deg DEC:0.83650 deg). Left: Pan-STARRS postage-stamp image. Clearly you can see the footprint of each individual chip (2.5*2.5 arcmin2). Also there is a dark area on top of the galaxy which passes through the galaxy. Right: SDSS data for the same galaxy.

  • The i-band image of PGC59376 (RA:254.78625 DEC:28.99200). There are a few odd dark region passing through the galaxy. the background noise is not uniformly distributed. Dark edges around the galaxy indicate background over subtraction. These feature are more-or-less available in most cases and that's the reason Pan-STARRS returns fainter results.

  • This table summarizes all the results.
no PGC d25 g.sdss r.sdss profile images note-sdss * g.ps r.ps profile images note-Pan-STARRS *
1 45947 1.95 13.28 12.55 profile images * 13.31 12.62 profile images *
2 21684 1.95 14.13 13.59 profile images * 14.13 13.57 profile images *
3 34718 1.91 13.82 13.36 profile images * 13.91 13.43 profile images *
4 43863 1.91 14.32 13.48 profile images * 14.37 13.54 profile images saturated center *
5 34913 1.91 13.95 13.09 profile images * 13.89 13.04 profile images *
6 30818 1.91 13.96 13.41 profile images * 14.15 13.59 profile images *
7 41958 1.91 13.50 12.79 profile images * 13.53 12.86 profile images *
8 37429 1.91 12.50 11.90 profile images * 12.66 12.07 profile images *
9 41020 1.86 14.73 14.48 profile images * 14.87 14.57 profile images *
10 19652 1.82 14.75 14.05 profile images * 14.71 14.09 profile images *
11 9510 1.82 14.74 14.00 profile images * 14.65 14.00 profile images *
12 43517 1.82 14.14 13.38 profile images * 14.13 13.46 profile images saturated center *
13 47971 1.82 13.30 12.72 profile images * 13.32 12.78 profile images *
14 23169 1.82 14.26 13.49 profile images * 14.22 13.47 profile images *
15 43837 1.86 12.75 12.23 profile images * 12.85 12.33 profile images background oversubtraction *
16 37723 1.86 12.89 12.45 profile images * 13.05 12.65 profile images bad background *
17 39366 1.74 13.84 13.48 profile images * 13.88 13.48 profile images *
18 52167 1.78 14.35 13.98 profile images * 14.45 14.01 profile images g-band background issue *
19 61220 1.7 profile images * 14.10 13.56 profile images saturated center *
20 12514 1.7 16.07 15.69 profile images * 16.14 15.91 profile images *
21 21918 1.7 14.51 13.77 profile images * 14.43 13.78 profile images *
22 54262 1.78 14.87 14.50 profile images * 14.93 14.60 profile images *
23 32786 1.74 13.69 13.13 profile images * 13.92 13.30 profile images saturated cneter *
24 50897 1.7 13.87 13.33 profile images * 14.04 13.45 profile images saturated center *
25 49995 1.66 13.09 12.25 profile images * 13.24 12.47 profile images saturated center *
26 60436 1.62 profile images * profile images *
27 70020 1.66 13.72 13.05 profile images * 13.83 13.18 profile images background oversubtraction *
28 35621 1.62 14.02 13.51 profile images * 14.04 13.64 profile images saturated center *
29 10029 1.62 13.90 13.02 profile images * 13.97 13.14 profile images *
30 53332 1.62 14.21 13.56 profile images * 14.16 13.57 profile images *
31 40516 1.66 12.29 11.78 profile images * 12.60 12.12 profile images saturated center *
32 59634 1.66 14.34 13.61 profile images * 14.35 13.63 profile images g-band uncertain *
33 11941 1.51 13.71 12.91 profile images * 13.69 13.02 profile images saturated center *
34 50853 1.51 14.64 13.98 profile images * 14.69 14.00 profile images *
35 43341 1.51 14.15 13.85 profile images * 14.56 14.08 profile images *
36 25781 1.55 14.35 13.88 profile images * 14.35 13.89 profile images *
37 27232 1.51 13.29 12.71 profile images * 13.30 12.77 profile images *
38 35405 1.58 13.31 12.87 profile images * 13.39 12.94 profile images *
39 46321 1.58 13.53 12.94 profile images * 13.68 13.09 profile images *
40 23646 1.55 14.34 13.65 profile images * 14.30 13.68 profile images saturated center *
41 66622 1.48 14.33 13.57 profile images * 14.32 13.57 profile images a few pixel at the center saturated *
42 40761 1.48 14.97 14.76 profile images low luminosity - high uncertainty * 15.22 15.20 profile images i-band data uncerain - artifact *
43 10542 1.41 14.69 13.91 profile images * 14.55 13.85 profile images *
44 6627 1.41 15.12 14.29 profile images done * 15.11 14.32 profile images *
45 26871 1.45 15.92 15.35 profile images * 16.05 15.41 profile images *
46 49489 1.48 12.58 11.91 profile images * 12.57 11.94 profile images *
47 47680 1.45 14.72 14.17 profile images * 14.73 14.16 profile images *
48 22827 1.41 13.61 13.16 profile images * 13.64 13.17 profile images *
49 50017 1.32 14.93 14.13 profile images * 15.06 14.16 profile images saturated center *
50 59498 1.32 13.94 13.46 profile images * 13.97 13.49 profile images *
51 23519 1.35 1.93 1.71 profile images sounds noisy * 14.16 13.61 profile images intense g-ban masking *
52 47935 1.35 15.52 14.75 profile images * 15.54 14.81 profile images *
53 11074 1.35 14.56 13.94 profile images * 14.54 13.92 profile images *
54 51155 1.32 14.11 13.39 profile images * 14.16 13.42 profile images *
55 26765 1.35 14.36 13.80 profile images * 14.45 13.80 profile images *
56 6982 1.32 13.57 12.84 profile images done * 13.62 12.91 profile images *
57 49838 1.29 14.58 13.97 profile images * 14.64 14.03 profile images *
58 55349 1.23 14.81 14.03 profile images * 15.01 14.19 profile images *
59 22381 1.23 13.57 12.85 profile images * 13.52 12.82 profile images *
60 55475 1.23 15.00 14.48 profile images * 14.99 14.50 profile images saturated center *
61 39113 1.29 15.30 14.95 profile images noisy uncertain z-band data * 15.51 15.21 profile images *
62 34692 1.26 13.33 12.90 profile images * 13.38 12.99 profile images *
63 64552 1.26 profile images * 14.07 13.46 profile images messy - heavy masking *
64 59735 1.2 14.14 13.75 profile images * 14.25 13.92 profile images g-band, llosing light ... background oversubtraction in all bands (probable) *
65 151574 1.1 14.93 14.15 profile images * 14.89 14.15 profile images *
66 50210 1.1 14.43 14.24 profile images * 14.72 14.44 profile images *
67 47305 1.12 15.20 14.62 profile images * 15.20 14.64 profile images *
68 22880 1.12 14.90 14.30 profile images * 14.90 14.35 profile images *
69 12775 1.15 16.23 15.48 profile images * 16.17 15.37 profile images *
70 62651 1.1 14.78 13.66 profile images very crowded * 14.68 13.78 profile images super messy, crowded field, tons of foreground stars *
71 56366 1.1 15.08 14.67 profile images * 15.07 14.68 profile images *
72 50262 1.1 13.78 13.52 profile images * 14.04 13.79 profile images *
73 32708 1.07 15.04 14.66 profile images * 15.32 14.70 profile images *
74 37740 1.0 15.87 15.68 profile images * 16.04 15.73 profile images *
75 53864 1.0 15.54 15.26 profile images no good z and u-bands * 15.47 15.22 profile images *
76 40408 1.05 14.86 14.45 profile images * 14.90 14.52 profile images *
77 507 1.02 14.87 14.12 profile images Done * 14.89 14.16 profile images *
78 33869 1.05 14.99 14.28 profile images * 14.99 14.29 profile images *
79 60049 1.07 15.71 15.03 profile images bright star at the center ... probably missing light * 15.61 15.01 profile images *
80 24469 1.0 14.67 14.12 profile images bright nearby galaxy, fuccy light around the galaxy. ... probably a disturbed system ... ejected gas !!!!? * 14.65 14.08 profile images bright close galaxy ... *
81 23465 0.98 15.13 14.80 profile images * 15.12 14.85 profile images *
82 71288 0.98 14.39 13.73 profile images * 14.40 13.86 profile images *
83 58514 0.91 16.36 15.53 profile images * 16.16 15.45 profile images *
84 49137 0.93 14.56 14.08 profile images * 14.57 14.09 profile images background oversubraction in g-band *
85 90968 0.91 5.80 5.55 profile images noisy, seems to be super bright (weird !!!) * 16.43 16.11 profile images super uncertain, bad background *
86 61254 0.91 15.02 14.25 profile images u-band not good, other bands uncertain, z-band seems to be Ok though ... the accuracy 0.1 mag * 15.29 14.60 profile images intense masking *
87 53891 0.95 18.38 17.29 profile images * 15.02 14.55 profile images very bright star next to the galaxy - super uncertain *
88 59376 0.91 14.64 13.99 profile images * 14.61 13.97 profile images *
89 54400 0.85 15.85 15.22 profile images * 15.83 15.21 profile images *
90 25111 0.83 14.68 14.36 profile images * 14.79 14.45 profile images *
91 68009 0.89 15.34 14.56 profile images * 15.24 14.51 profile images *
92 91489 0.89 16.28 15.54 profile images * 16.23 15.52 profile images *
93 6678 0.89 15.41 14.79 profile images * 15.48 14.78 profile images *
94 24977 0.85 15.26 14.57 profile images * 15.27 14.56 profile images loosing light on the edges !!! *
95 24012 0.85 14.75 14.35 profile images * 14.76 14.33 profile images *
96 67626 0.89 14.52 13.91 profile images * 14.55 13.97 profile images *
97 23026 0.78 14.24 13.81 profile images * 14.27 13.80 profile images *
98 47966 0.74 15.31 14.68 profile images * 15.21 14.64 profile images *
99 4010299 0.74 16.45 16.05 profile images looks like a blob ... probably not good for distance measurments * 16.52 16.23 profile images *
100 22918 0.78 14.64 13.89 profile images * 14.62 13.91 profile images *
101 60271 0.72 16.14 15.84 profile images * 16.09 15.86 profile images *
102 58700 0.78 16.89 16.34 profile images * 16.90 16.34 profile images *
103 91110 0.71 16.79 16.33 profile images * 16.85 16.52 profile images *
104 52350 0.79 15.15 14.55 profile images * 15.15 14.51 profile images *
105 91488 0.68 16.88 16.37 profile images * 16.88 16.36 profile images *
106 43840 0.68 15.44 14.89 profile images * 15.48 14.94 profile images *
107 23033 0.63 16.61 15.92 profile images * 16.88 16.16 profile images g-band has problems *
108 55844 0.65 14.88 14.18 profile images * 14.80 14.13 profile images *
109 40943 0.6 15.32 14.94 profile images * 15.40 14.99 profile images *
110 38457 0.62 15.62 15.23 profile images * 15.57 15.56 profile images very bad data *
111 91516 0.66 16.71 16.10 profile images * 16.58 16.25 profile images *
112 67891 0.65 15.75 15.13 profile images * 15.66 15.07 profile images *
113 51293 0.58 15.54 15.13 profile images super face-on * 15.41 14.99 profile images *
114 214939 0.58 16.81 16.14 profile images * 16.83 16.33 profile images *
115 22218 0.59 15.69 15.26 profile images * 15.67 15.30 profile images *
116 91009 0.5 17.28 16.78 profile images * 17.24 16.83 profile images *
117 51230 0.58 15.68 15.23 profile images * 15.62 15.18 profile images *
118 30263 0.55 13.94 13.47 profile images * 13.94 13.48 profile images *
119 39038 0.56 15.54 15.00 profile images * 15.50 14.98 profile images *
120 51144 0.56 15.66 15.31 profile images * 15.74 15.34 profile images *
121 165902 0.47 15.82 15.06 profile images * 15.75 15.04 profile images *
122 169959 0.49 16.59 16.13 profile images * 16.75 16.31 profile images *
123 100776 0.4 15.58 14.91 profile images * 15.54 14.89 profile images *
124 33529 0.48 15.85 15.47 profile images z-band magnitude Not reliable ! * 16.07 15.49 profile images *
125 22630 0.4 15.96 15.45 profile images * 15.96 15.50 profile images *
126 90854 0.49 17.19 16.67 profile images * 17.17 16.73 profile images bad g-band data *
127 139387 0.42 16.95 16.50 profile images * 16.96 16.49 profile images *
128 3460270 0.48 16.43 15.93 profile images * 16.51 15.99 profile images *
129 49294 0.39 15.21 14.76 profile images bad U-band magnitude * 15.39 14.84 profile images *
130 38963 0.35 16.19 15.80 profile images * 16.10 15.88 profile images *
131 140542 0.35 16.14 15.72 profile images * 16.06 15.76 profile images *
132 142843 0.38 16.64 16.22 profile images There is an edge-on nearby galaxy. There is chance tht the HI measurments are confused. Not recommended for distance measurements * 16.64 16.25 profile images *
133 1331483 0.37 16.03 15.63 profile images * 15.94 15.57 profile images *
134 39342 0.37 15.19 14.90 profile images * 15.26 14.93 profile images *
135 23531 0.35 16.53 16.16 profile images * 16.61 16.16 profile images *
136 91191 0.35 4.43 4.51 profile images bad image, good photometry * 16.69 16.51 profile images *
137 1701087 0.28 16.53 16.43 profile images No good z-band profile * 16.63 16.45 profile images *
138 39833 0.2 16.78 16.47 profile images bad z/u bands * 17.83 17.48 profile images super uncertain - bright star in the field . bad data *
139 48409 0.28 16.07 15.76 profile images bright galaxy next to the center,bad z-band, gri magnitudes seems to be ok * 16.21 15.81 profile images bright objsct near the center ... probability of contamination *
140 41716 0.28 15.37 14.86 profile images * 15.56 14.94 profile images *
141 1672298 0.28 18.04 17.14 profile images super faint, no morphology can be determined * 17.77 17.10 profile images bad SB profile .... *
142 1305231 0.27 16.53 16.49 profile images No good magnitude .. next to a bright star ... * 17.20 17.04 profile images Terrible *
143 35380 0.2 14.06 13.75 profile images * 14.19 13.84 profile images *
144 91775 0.26 16.27 15.81 profile images * 16.25 15.82 profile images *
Last modified 4 years ago Last modified on Dec 7, 2016, 8:15:23 PM

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