Filter test with spectrometer
Posted 29/02/2012 - 13:31
Link
Very Interesting. I'll have to compare the spectra of my UV filters with what they've got. (I've only run the spectra on one to date and that in absorbance rather than transmission)
They do have one minor error though - the Hot mirror used infront of the sensor to reduce the sensitivity to IR does also significantly reduce the sensors response to UV. (section 2 states otherwise).
I've found this to my disadvantage in trying to record UV images
In fact many such as link have less UV transmission than most of the filters under test. This example is 1% transmission at 390nm whilst better than 85% from 410nm to 700nm.
It would be intertsing to see comparative spectra for actual sensor response against various films, but I'm not sure that would be easy to produce.
They do have one minor error though - the Hot mirror used infront of the sensor to reduce the sensitivity to IR does also significantly reduce the sensors response to UV. (section 2 states otherwise).
I've found this to my disadvantage in trying to record UV images
In fact many such as link have less UV transmission than most of the filters under test. This example is 1% transmission at 390nm whilst better than 85% from 410nm to 700nm.
It would be intertsing to see comparative spectra for actual sensor response against various films, but I'm not sure that would be easy to produce.
Mike
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Pentax:K5ii, K7, K100D, DA18-55, DA10-17, DA55-300, DA50-200, F100-300, F50, DA35 AL, 4* M50, 2* M135, Helicoid extension, Tak 300 f4 (& 6 film bodies)
3rd Party: Bigmos (Sigma 150-500mm OS HSM),2* 28mm, 100mm macro, 28-200 zoom, 35-80 zoom, 80-200 zoom, 80-210 zoom, 300mm M42, 600 mirror, 1000-4000 scope, 50mm M42, enlarger lenses, Sony & micro 4/3 cameras with various PK mounts, Zenit E...
Far to many tele-converters, adapters, project parts & extension tubes etc.
.[size=11:].Flickr• WPF• Panoramio
.
Pentax:K5ii, K7, K100D, DA18-55, DA10-17, DA55-300, DA50-200, F100-300, F50, DA35 AL, 4* M50, 2* M135, Helicoid extension, Tak 300 f4 (& 6 film bodies)
3rd Party: Bigmos (Sigma 150-500mm OS HSM),2* 28mm, 100mm macro, 28-200 zoom, 35-80 zoom, 80-200 zoom, 80-210 zoom, 300mm M42, 600 mirror, 1000-4000 scope, 50mm M42, enlarger lenses, Sony & micro 4/3 cameras with various PK mounts, Zenit E...
Far to many tele-converters, adapters, project parts & extension tubes etc.
.[size=11:].Flickr• WPF• Panoramio
Posted 29/02/2012 - 15:02
Link
Seconded.
Likewise the other information on the site
Many thanks
Bernard
Likewise the other information on the site
Many thanks
Bernard
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Best regards