4 replies to this topic

[ngc2218]

A few years back I got a Astrodon 50R Exoplanet Blue Blocking filter. Haven't used it yet, but I feel it's time to move on from 'pretty pictures'.

Is it a requirement for exoplanet transits or any filter will do? I also have a Sloan g'r'i' set.

What is the recommendation?

 

[GaryShaw]

Hi

Unless you are part of the Tess SG1 group ( pre-qualification required ), there are no actual ‘requirements’ relative to filters that I’m aware of. You could also go unfiltered.

 

When I started submitting transit analyses on ‘confirmed’ exoplanets via the AAVSO upload portal, I was using a photometric V filter. Then I switched to a CBB, Clear Blue Blocking filter such as you mention. As part of the SG1 group, working on exoplanet ‘candidates’, the SG1 Group Leader specifies ( in the Target Transit Finder ‘comment’ column ) what filter is to be used on each planet candidate for the next analysis. There is quite a range of filters there which includes those that you list.

 

If you’re just starting out, I’d suggest you begin by getting very familiar with the AAVSO ‘Exoplanet Section’ information, including following the ‘Guide’ which outlines pretty much all aspects of target selection, image capture, transit analysis and reporting using AIJ. AIJ is the gold standard application for this work and is used by both those working on ‘confirmed’ and ‘candidate’ exoplanets. The ‘Guide’ can take you through a ‘sample transit analysis’ using a provided science image set for WASP12b and accompanying calibration images. It’s a great way to get started. There’s also an AAVSO Choice course on analyzing and reporting Exoplanet Observations that is taught by Dennis Conti, the Exoplanet Section Leader. It’s excellent.

 

In addition to the AAVSO process that I’ve outlined so far, if you’re interest in a more casual approach, you can work on ‘confirmed’ exoplanets with a NASA- sponsored outreach group called ‘Exoplanet Watch’. This group is lead and managed by NASA and utilizes it own customized python-based tools. 
 

Whatever your level of interest, there are great training materials and various team options to consider as well as just simply doing the analyses on your own and submitting via the AAVSO portal.
Hope this helps a bit. 
Gary 

[ngc2218]

Thanks Gary, I'll start with the reading material by Dennis Conti, and go from there

[gregj888]

If you look at the data for Astrodon 50R Exoplanet Blue Blocking filter is a 500nm low pass filter.  Any of the yellow low pass filters will yield an indistinguishable result: OK, IMHO.

 

That filter cuts the blue end as has been mentioned.  Blue is the most sensitive to seeing and scatters the most.  So this adds a little stability to the captures but there are other ways around that.

 

If you have a camera that is red sensitive, like a QHYiii462m, you could drop that further to 600n or 680nm.  As Gary said, none of this is really essential. 

 

Also check the information at NASA's Exoplanet Watch.  They work with AAVSO but have some additional information.  I believe their captures are unfiltered.

[Xilman]

A few years back I got a Astrodon 50R Exoplanet Blue Blocking filter. Haven't used it yet, but I feel it's time to move on from 'pretty pictures'.

Is it a requirement for exoplanet transits or any filter will do? I also have a Sloan g'r'i' set.

What is the recommendation?

Check out the ExoClock project at https://www.exoclock.space where you will be able to do valuable scientific work on exoplanet transits with the filter set you already have, or with no filters at all.