Talk:Hydrargyrum medium-arc iodide lamp

Untitled
The "Films Using Them" section should be removed, as it gives the false impression that there is something rare or notable about films using HMIs. Almost every one of the dozens of movies I've worked on has used them. El Mariachi

Etymology
I reverted out a change that someone made linking the "Hydrargyrum" in the keyword to mercury. If this was done to show the etymology of the name, we should probably just create an explicit "Etymology" section instead.

Atlant 10:59, 19 Apr 2005 (UTC)


 * I don't think the etymology needs a whole section to itself, but since Hydrargyrum is a very uncommon term for mercury, it's more important to have a link for people who don't know what it means -- they wouldn't necessarily guess to follow the mercury link. Maybe a parenthetical?  It looks a little clumsy.  El Mariachi


 * I've edited the page to say "Hydrargyrum comes from the Latin name for the element mercury". It's clear that this is the meaning of the name. The previous description explained the etymology of an outdated term for the element mercury, which has zero relevance for the article. Nitro2k01 (talk) 08:36, 9 June 2017 (UTC)

(cur) (last) 16:05, 19 Apr 2005 Atlant (How's this?)


 * Nice!

Green spike
The reference to correcting the 'curse' of the HMI green spike is problematic for two reasons. Firstly, as a working gaffer I find that DoPs much more often want to warm up HMI's, specifying gels such as 1/8 CTO, 1/4 CTO or Pale Amber Gold, than to cool them with CTB as suggested in the article. Secondly, if the idea was to compensate for a green spike the correct gel would be 1/8 or 1/4 Minus Green as used on some practical flourescants. CTB does not correct a green spike. —The preceding unsigned comment was added by 80.229.220.14 (talk)

Difference with MH lamps
No mention is made of metal halide lamps, although in my perception these lamps are very similar in operation to HMI lamps

Gerben49 12:20, 8 October 2006 (UTC)gerben49

In fact, they are metal-halide lamps. We manufacture (the QMH line) metal-halide lamps marked HQI, HMI, HgMI, MBIL, SPL etc. They are metal-halide series rather than different lamp types.

BTW, the green curse is caused by thallium. Thallium emits a strong single green (535 nm, if I recall) line. It is used to pump up lumens/watt (near to human eye sensitivity maximum), but doesn't help color rendering as being a single line. Valdez —Preceding unsigned comment added by 84.0.210.189 (talk) 09:16, 17 August 2008 (UTC)

(R)
I assume the (R) is meant to be the registered trademark sign. I'm fixing it. Camerajohn (talk) 21:43, 16 August 2009 (UTC)

Poor English usage
This article needs rewriting to correct poor English language usage. Moreover, it is more common to refer to incandescent light sources than to "tungsten units." Epaulard (talk) 05:39, 3 October 2009 (UTC)

wattages in film industry....
It might be helpful to list common wattage of lamps... There are statements referring to wattage but it is never explicitly mentioned what scale we are talking about:

"The efficiency advantage is near fourfold, with approximately 85-108 lumens per watt of electricity."

"Multi-kilowatt HMI lights are used in the film industry and for large-screen slide projection because of their daylight-balanced light output, as well as their efficiency."

A reader might otherwise assume wattage comparable to incandescents. In my estimation these might be: 200, 400, 575, 800, 1200, 2500, 4000, 6000, 12000, 18000. —Preceding unsigned comment added by 75.83.36.180 (talk) 20:50, 19 November 2009 (UTC)

photo of ballast
Also the ballast photo is not a very good one and gives no impression of what it actually is. To the uninitiated, it is just a photo of a fan. —Preceding unsigned comment added by 75.83.36.180 (talk) 20:54, 19 November 2009 (UTC)

inconsistent terminology
I'm trying to clean this up some, bring it a little more in line with the rest of the lighting section... Yamagawa10k (talk) 05:26, 26 October 2010 (UTC)

TV frame rates or film camera frame rates
The Ballast operation section says "This is why TV standards typically use the power grid frequency as their basic frame rate." I've flagged this as since Broadcast_television_systems says TV frame rate chosen to avoid magnetic field beats. - Rod57 (talk) 13:23, 31 August 2015 (UTC)
 * Cinematography sources eg suggest it is the film frame rate that had to be related to the power supply frequency to avoid flicker using lights with 'magnetic' ballasts. Could change text to "This is why 'safe' film camera frame rates are an integer fraction of the local power supply frequency, (eg. 24=120/5)." ? - Rod57 (talk) 14:23, 31 August 2015 (UTC)