# LSST Filters versus SDSS

**URL:** <https://www.rubin.community/t/lsst-filters-versus-sdss/2429>\
**Category:** Data Products\
**Created:** [November 23, 2017, 12:02am UTC](https://www.rubin.community/t/lsst-filters-versus-sdss/2429 "2017-11-23T00:02:44Z")\
**Posts on this page:** 1\
**Showing post:** 6

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**Author:** ![MelissaGraham](https://sea2.discourse-cdn.com/flex002/user_avatar/www.rubin.community/melissagraham/32/2549_2.png) [@MelissaGraham](https://www.rubin.community/u/MelissaGraham)\
**Post date:** [November 27, 2017, 7:37pm UTC](https://www.rubin.community/t/lsst-filters-versus-sdss/2429/6 "2017-11-27T19:37:22Z")

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Hi @yorkpf, thank you for your question.

You are correct that the LSST has six filters, ugrizy. These bands do not exactly match the SDSS bands. For a quick comparison, see the relevant plots below, which are from [Filter Response Curves — speclite v1.0.1.dev3](http://speclite.readthedocs.io/en/latest/filters.html).

 ![sdss2010](https://us1.discourse-cdn.com/flex002/uploads/rubin/original/1X/e814c57e114bfd0b9d9ad20f469b88f4307c51a2.png)  
 ![lsst2016](https://us1.discourse-cdn.com/flex002/uploads/rubin/original/1X/a3fe6cf8acf30d8e9cc66b4c8b5d022fc509a696.png)

If you’re looking for more information or would like access to the transmission curves themselves, the best place to start is the left-hand menu bar of the “for scientists” page at [For Scientists | Rubin Observatory](https://www.lsst.org/scientists). There you will find a link to Filter Throughputs which takes you to a GitHub repository of filter transmission curves ([GitHub - lsst/throughputs: LSST Simulations repository for baseline evaluation information · GitHub](https://github.com/lsst/throughputs)). As the readme file describes, the LSST throughput curves are in the “baseline” directory, and those are the ones you should use to, e.g., calculate expected magnitudes. For a more detailed comparison of various filter systems with the LSST filters, and/or code to use to make plots like the ones shown above, visit [Filter Response Curves — speclite v1.0.1.dev3](http://speclite.readthedocs.io/en/latest/filters.html).

Thanks again for posting your question, and if you have any further questions on this topic please don’t hesitate to reply to this thread.

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