by geckzilla » Wed Dec 09, 2015 8:25 pm
tjerome wrote:
Wow--that's an impressive demonstration. I gather you used some sort of plate solve to superimpose the star names over the photo, but how did you make the second slide match up perfectly and package it into a clickable demo? I'd love to know how to make a comparison like that.
Ted
It is easy if you already know how but could be fairly difficult without some skills built up in a few different areas first. I took the screenshot in Stellarium knowing the location and date using a perspective projection since that most closely matches the single exposure camera shot. Then, with the two images in Photoshop, I use something called a puppet warp on the screenshot and pin matching stars in place. I try to do the most obvious stars/planets that are far apart first and then match up the smaller details. The web page is just some simple css, html, and javascript.
Since I already did most of the work matching the screenshot with the photo a few nights ago for the annotation, I didn't mind putting this together quickly, especially for the sake of destroying the accusations made against the photographer. I probably would have done it anyway... nothing pushes my buttons more than new users who pop in here just to try to bring someone down.
[quote="tjerome"][quote="geckzilla"]http://www.geckzilla.com/apod/AuroraIceland_Ryan_swap.html[/quote]
Wow--that's an impressive demonstration. I gather you used some sort of plate solve to superimpose the star names over the photo, but how did you make the second slide match up perfectly and package it into a clickable demo? I'd love to know how to make a comparison like that.
Ted[/quote]
It is easy if you already know how but could be fairly difficult without some skills built up in a few different areas first. I took the screenshot in Stellarium knowing the location and date using a perspective projection since that most closely matches the single exposure camera shot. Then, with the two images in Photoshop, I use something called a puppet warp on the screenshot and pin matching stars in place. I try to do the most obvious stars/planets that are far apart first and then match up the smaller details. The web page is just some simple css, html, and javascript.
Since I already did most of the work matching the screenshot with the photo a few nights ago for the annotation, I didn't mind putting this together quickly, especially for the sake of destroying the accusations made against the photographer. I probably would have done it anyway... nothing pushes my buttons more than new users who pop in here just to try to bring someone down.