Space Warps Talk

Simulated lenses we cannot see

  • gbcaminha by gbcaminha

    Spacewarps tells me there is a simulated lens in this field, but I cannot see any strong lensing feature.
    Is there more images with this issue?
    Is there any criteria in the simulations in order to select only visible arcs/multiple-images?

    Posted

  • gbcaminha by gbcaminha

    enter image description here

    Same thing happens in this image.
    In principle there is a simulated lens near to the up-right star.

    Posted

  • bruckner2zoo by bruckner2zoo in response to gbcaminha's comment.

    in the 2nd image is the lens in the top center - what looks like a double star? the arc is the left side?

    Posted

  • geckzilla by geckzilla

    I keep running across simulated lenses which I either can't see or it's a quasar with only a single visible quasar on one side of a lensing object and no quasar on the other side... so it's not a double or an Einstein cross so I've been getting a few of them wrong. Then I come across one that I think is another fake single quasar and it turns out to be a confirmed non lens. It's frustrating. I haven't figured out how to view my previous images yet either so I can't point out the ones I wish to discuss.

    Posted

  • Tom_Collett by Tom_Collett scientist

    Some lenses are hard to spot! It's okay to miss simulated lenses and we actually learn a lot from the missed lenses too.

    One thing that is interesting is quantifying exactly how common lensing is, because it tells us about the density of background sources and potential lenses on the sky. Obviously nobody is perfect, so we wont find all the lenses; we need to know how many real lenses are missed if we are to quantify the lensing rate. Every time you miss a simulated lens, you are helping us understand how many real lenses are likely to be missed by the spacewarps collaboration.

    Posted

  • Tanksenior by Tanksenior

    Yeah I just missed my first one when I hit about 150 images viewed, some of them are really difficult to make out.

    Posted

  • drphilmarshall by drphilmarshall scientist, admin

    OK, got some feedback from the dev team: when you see this problem, can you "collect" the image, or tag it as #missingsim, please? The reason is that to diagnose the problem, they need the Zooniverse ID of the image, not just the image... Thanks for helping out!

    Posted