Can 4k and 2,5k HMI's give the same light output?
Posted 24 November 2017 - 03:11 AM
Posted 24 November 2017 - 07:26 AM
There's no way to judge without a meter. The eye compensates. Likewise we can't tell whether you exposure for each shot was identical.
The spot setting is clearly brighter.
Posted 24 November 2017 - 07:41 AM
Do you have any fresnel lens attached at the front?
Posted 24 November 2017 - 07:44 AM
Yes, they both are fresnels and have fresnel lenses
Posted 24 November 2017 - 09:52 AM
Output also depends a lot on the reflector and (not as much) on lens diameter. And Sirios have smaller lenses than old-school fixtures like LTM Luxarc - but that doesn't make them 2x less in output, of course.
Check if the reflectors are clean, make sure the ballass are set to correct mains voltages (big magnetic ballast have separate primary winding taps for 250, 230, 200V, etc).
I won't trust my eyes in such a test, lights are something like 50 000 and 30 000 lux spotted, kind of hard to distinguish in a dim room.
Edited by Michael Rodin, 24 November 2017 - 09:53 AM.
Posted 29 November 2017 - 12:06 PM
Thank you for help,
I'll order light meter, time to start use it anyway
Posted 13 December 2017 - 03:24 PM
Sekonic L-508 zoom master is a great meter you can get one used for very little. Features a spot meter as well as incident which can be handle if you want to measure reflectivity vs incident (light falling on meter).