| | 63 | |
| | 64 | = MD.V3 Tessellation = |
| | 65 | |
| | 66 | The new V3 tessellations are defined at [wiki:PS1_Tessellations] with the following general properties: |
| | 67 | |
| | 68 | * 0.25"/pix (from natural ~0.258"/pixel, previously warped to 0.2"/pix up through V2) |
| | 69 | * 10 x 10 skycell grid (previously 12 x 12) |
| | 70 | * +x is West (flipped from before +x was East), +y is still North |
| | 71 | * 320 pixel (80") overlap (from 300 pixels, 60", in V2) |
| | 72 | * revised centers (if necessary) -- see relevant MD section for more details and the MDS field table (http://ps1sc.ifa.hawaii.edu/PS1wiki/index.php/Medium_Deep_Survey#Actual_Field_Centeres_-_2011-02-21) but in summary |
| | 73 | * [wiki:MD.GR0#MD10.GR0 MD10.GR0]: from (351.979 -0.433) to (352.312, -0.433) however an additional offset looks like it should have been applied to cover more of the earlier observation dithers. |
| | 74 | * [wiki:MD.GR0#MD07.GR0 MD07.GR0]: from (213.146, +53.417) to (213.454, +53.243) to best cover as much of the earlier observation dithers as possible. |
| | 75 | * [wiki:MD.GR0#MD08.GR0 MD08.GR0]: very slight offset in RA to the W to just align with the MDS field pointing. |
| | 76 | * [wiki:MD.GR0#MD09.GR0 MD09.GR0]: from (333.688, +0.283) closer to the current pointing of (334.188, +0.283) however an addition offset was added to move the center about half a skycell to the E to (333.980, +0.283) in order to cover as much of the earlier observation dithers as possible. |
| | 77 | * All fields should be looked at to see if there are any problems with the new tessellation and dither pattern. |
| | 78 | * [wiki:MD.GR0#MD07.GR0 MD07], [wiki:MD.GR0#MD09.GR0 MD09] will have a preliminary nightly stack made for testing the revised center as well as [wiki:MD.GR0#MD06.GR0 MD06] for NGC4258. |
| | 79 | |
| | 80 | |
| | 81 | = Reference versus Deep Stack = |
| | 82 | A requirements description for the needs in the different types of stacks would be useful to summarize. |
| | 83 | |
| | 84 | Reference stacks -- primarily for difference imaging for transient detection and necessary for magic destreaking. |
| | 85 | * Magic destreaking: a fairly clean reference stack (uses the convolved stack) with as much spatial area coverage as possible to enable release of non-stack data products. Particularly important is inclusion of older data on different pointings and of course a fairly balanced dither set. |
| | 86 | * Transient detection: a balance slanted towards best PSF but with some depth (1-1.5 magnitudes over nightly stacks) and also a fairly balanced dither set. better with more recent data to limit AGN/variable star variations. |
| | 87 | |
| | 88 | Deep stacks -- for deep static sky science. |
| | 89 | * As deep as possible.. maximum FWHM allowance? minimum exposure time? specific request for at least ~10ks has been requested, with best FWHM possible and also a fairly balanced dither set.. |
| | 90 | |
| | 91 | See summary for each MD field reference stack for details on specifics for that field. Due to processing+time constraints/early mistakes, an attempt has been made to merge the similar criteria under the ''refstack'' label. |
| | 92 | |
| | 93 | Since magic destreaking uses the convolved stack, looking into a quickstack version of the unconvolved stacks for the transients reference and deep stack that will be faster to make with more inputs. |
| | 94 | |
| | 95 | For cases when a stack does not have a good sample of exposures with a reasonably small PSF FWHM, it should be possible to generate a reference stack with the fewer 'best' exposures for just SSdiffs and transient detection. MD02-g may be such a case. |
| | 96 | |
| | 97 | For fields with shifted centers from offset earlier exposures, inclusion of enough exposures to provide a reference stack for magic is necessary in order for data from those associated chips/skycells to be distributed (being older data, may not have the optimum quality). Mixing older and newer data may also be a detriment. |
| | 98 | |
| | 99 | Related to deep stacks, there needs to be enough inputs to obtain minimum depth that is as pixel contiguous as possible (see MD04 deep stack tests). |
| | 100 | |
| | 101 | How much of a varying IQ can go into a stack before ppSub has difficulty modeling the variations within a skycell? |
| | 102 | |
| | 103 | Deep stacks on hold until finish investigating overly large PSF in the convolved stacks dependent on the number of input warps. |
| | 104 | |
| | 105 | Without need for magic for releasing older data, should focus on more recent data going into the refstacks |
| | 106 | |
| | 107 | == post-Magic January 2012 == |
| | 108 | |
| | 109 | = Reprocessed Data Products = |
| | 110 | |
| | 111 | == Chip/Warp == |
| | 112 | Currently processed but not distributed due to disk space load. Can be obtained via the Postage Stamp Server. |
| | 113 | |
| | 114 | == Camera/SMFs == |
| | 115 | Fully processed and distributed. |
| | 116 | |
| | 117 | == Nightly Stacks == |
| | 118 | All nights reprocessed and stacked into a nightly stack using the current nightly stack configurations. |
| | 119 | * should attempt to make stack with 2 or more input warps now |
| | 120 | * some nights have >8 exposures, often in marginal conditions. Choices could/should be made in those cases (need to add details on current settings) |
| | 121 | |
| | 122 | == Difference Images == |
| | 123 | Need to finish the convolution choice (input stack or reference stack) before started. (Need to outline interests for these if any) |
| | 124 | |
| | 125 | |
| | 126 | == Static Sky == |
| | 127 | What to run on, reference stack and/or deep stack (TBD) |
| | 128 | |
| | 129 | |
| | 130 | |
| 94 | | |
| 95 | | = MD.V3 Tessellation = |
| 96 | | |
| 97 | | The new V3 tessellations are defined at [wiki:PS1_Tessellations] with the following general properties: |
| 98 | | |
| 99 | | * 0.25"/pix (from natural ~0.258"/pixel, previously warped to 0.2"/pix up through V2) |
| 100 | | * 10 x 10 skycell grid (previously 12 x 12) |
| 101 | | * +x is West (flipped from before +x was East), +y is still North |
| 102 | | * 320 pixel (80") overlap (from 300 pixels, 60", in V2) |
| 103 | | * revised centers (if necessary) -- see relevant MD section for more details and the MDS field table (http://ps1sc.ifa.hawaii.edu/PS1wiki/index.php/Medium_Deep_Survey#Actual_Field_Centeres_-_2011-02-21) but in summary |
| 104 | | * [wiki:MD.GR0#MD10.GR0 MD10.GR0]: from (351.979 -0.433) to (352.312, -0.433) however an additional offset looks like it should have been applied to cover more of the earlier observation dithers. |
| 105 | | * [wiki:MD.GR0#MD07.GR0 MD07.GR0]: from (213.146, +53.417) to (213.454, +53.243) to best cover as much of the earlier observation dithers as possible. |
| 106 | | * [wiki:MD.GR0#MD08.GR0 MD08.GR0]: very slight offset in RA to the W to just align with the MDS field pointing. |
| 107 | | * [wiki:MD.GR0#MD09.GR0 MD09.GR0]: from (333.688, +0.283) closer to the current pointing of (334.188, +0.283) however an addition offset was added to move the center about half a skycell to the E to (333.980, +0.283) in order to cover as much of the earlier observation dithers as possible. |
| 108 | | * All fields should be looked at to see if there are any problems with the new tessellation and dither pattern. |
| 109 | | * [wiki:MD.GR0#MD07.GR0 MD07], [wiki:MD.GR0#MD09.GR0 MD09] will have a preliminary nightly stack made for testing the revised center as well as [wiki:MD.GR0#MD06.GR0 MD06] for NGC4258. |
| 110 | | |
| 111 | | |
| 112 | | = Reference versus Deep Stack = |
| 113 | | A requirements description for the needs in the different types of stacks would be useful to summarize. |
| 114 | | |
| 115 | | Reference stacks -- primarily for difference imaging for transient detection and necessary for magic destreaking. |
| 116 | | * Magic destreaking: a fairly clean reference stack (uses the convolved stack) with as much spatial area coverage as possible to enable release of non-stack data products. Particularly important is inclusion of older data on different pointings and of course a fairly balanced dither set. |
| 117 | | * Transient detection: a balance slanted towards best PSF but with some depth (1-1.5 magnitudes over nightly stacks) and also a fairly balanced dither set. better with more recent data to limit AGN/variable star variations. |
| 118 | | |
| 119 | | Deep stacks -- for deep static sky science. |
| 120 | | * As deep as possible.. maximum FWHM allowance? minimum exposure time? specific request for at least ~10ks has been requested, with best FWHM possible and also a fairly balanced dither set.. |
| 121 | | |
| 122 | | See summary for each MD field reference stack for details on specifics for that field. Due to processing+time constraints/early mistakes, an attempt has been made to merge the similar criteria under the ''refstack'' label. |
| 123 | | |
| 124 | | Since magic destreaking uses the convolved stack, looking into a quickstack version of the unconvolved stacks for the transients reference and deep stack that will be faster to make with more inputs. |
| 125 | | |
| 126 | | For cases when a stack does not have a good sample of exposures with a reasonably small PSF FWHM, it should be possible to generate a reference stack with the fewer 'best' exposures for just SSdiffs and transient detection. MD02-g may be such a case. |
| 127 | | |
| 128 | | For fields with shifted centers from offset earlier exposures, inclusion of enough exposures to provide a reference stack for magic is necessary in order for data from those associated chips/skycells to be distributed (being older data, may not have the optimum quality). Mixing older and newer data may also be a detriment. |
| 129 | | |
| 130 | | Related to deep stacks, there needs to be enough inputs to obtain minimum depth that is as pixel contiguous as possible (see MD04 deep stack tests). |
| 131 | | |
| 132 | | How much of a varying IQ can go into a stack before ppSub has difficulty modeling the variations within a skycell? |
| 133 | | |
| 134 | | Deep stacks on hold until finish investigating overly large PSF in the convolved stacks dependent on the number of input warps. |
| 135 | | |
| 136 | | Without need for magic for releasing older data, should focus on more recent data going into the refstacks |
| 137 | | |
| 138 | | == post-Magic January 2012 == |
| 139 | | = Reprocessed Data Products = |
| 140 | | |
| 141 | | == Chip/Warp == |
| 142 | | Currently processed but not distributed due to disk space load. Can be obtained via the Postage Stamp Server. |
| 143 | | |
| 144 | | == Camera/SMFs == |
| 145 | | Fully processed and distributed. |
| 146 | | |
| 147 | | == Nightly Stacks == |
| 148 | | All nights reprocessed and stacked into a nightly stack using the current nightly stack configurations. |
| 149 | | * should attempt to make stack with 2 or more input warps now |
| 150 | | * some nights have >8 exposures, often in marginal conditions. Choices could/should be made in those cases (need to add details on current settings) |
| 151 | | |
| 152 | | == Difference Images == |
| 153 | | Need to finish the convolution choice (input stack or reference stack) before started. (Need to outline interests for these if any) |
| 154 | | |
| 155 | | |
| 156 | | == Static Sky == |
| 157 | | What to run on, reference stack and/or deep stack (TBD) |
