Hi
I referred to list on CN which I could not find a link to after a data disaster(My only one).
But on holiday I found a link to data Christian V posted here earlier:
Daystar Yellow Absorb 29% Transmit 71%
Daystar Red Absorb 30% Transmit 60%
Astronomic L Reflect?49% Transmit 51% I assume a dielectric UV/IR would be similar
Astronomic Blue Reflect?75% Transmit 25%
Baader D-ERF Reflect?83% Tansmit 17%
Beloptik ERF Reflect?90% Transmit 10%
You said you had done an analysis of the Baader 35nm filter and that showed 27% transmitted.
Why when the Baader D-ERF has a 100nm passband does it transmit less than the 35nm?
I assume the bigger filter is harder/more expensive to coat so has less coatings so larger pass band?
Cheers. Andrew.
F/A Merlin. ERF Transmissions
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Re: F/A Merlin. ERF Transmissions
Andrew,
Corrected and updated figures were posted on the 10th March (viewtopic.php?f=9&t=27325)
D-ERF = 20% transmission (350-2500nm)
35nm Baader Ha = 14% transmission (350-2500nm)
Don't know about Beloptic ERF - need to verify.
http://www.sonnen-filter.de/Filter-1/KG3-UV-lin.jpg
Looks like 90% across the VIS, = 0.9 x 0.43 (total energy in VIS) = 38.7% transmission (350-2500nm)
Corrected and updated figures were posted on the 10th March (viewtopic.php?f=9&t=27325)
D-ERF = 20% transmission (350-2500nm)
35nm Baader Ha = 14% transmission (350-2500nm)
Don't know about Beloptic ERF - need to verify.
http://www.sonnen-filter.de/Filter-1/KG3-UV-lin.jpg
Looks like 90% across the VIS, = 0.9 x 0.43 (total energy in VIS) = 38.7% transmission (350-2500nm)
"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
https://groups.io/g/astronomicalspectroscopy
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
https://groups.io/g/astronomicalspectroscopy
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
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