Sorry, been tied up and haven't checked the list lately.
RE: 35mm speed; 18 IPS (90 FPM) was always the standard for 24 FPS 35mm
film. The only variant at that time might have been 25 FPS for European
production. In the late 70's, there was were also productions that shot
at 30 FPS, but that was much later. (Note that this EQ standard differs
from the Cinemascope EQ used for 4 track release prints, which has a
different LF characteristic).
The standard for SMPTE 35mm magnetic EQ for studio recordings has mostly
been in the neighborhood of 35µs, but the standards have been revisited
a few times over the years. The most significant change was around 1971
or so, when an attempt was made to standardize the expression all film
EQ curves in terms of time-constants, as opposed to the
frequency-domain. In addition, work was done to standardize the
measurement and expression of levels in nW/m.
While both RCA and Westrex pretty much adhered to the SMPTE standards
during the 1950's (within the limitation of the heads and transformers
used back then), many Hollywood studios had their own "house standard",
which always made life interesting. When Dolby A came into the picture,
though, they made an effort to have better agreement on what the actual
standard would be, so as to promote interchangeability.
The other problem was that the SMPTE M35-MF "standard" test films were
notorious for variations, even up through the early 1980's. There were
plenty of factors that contributed to this, with major headaches being
azimuth and the dynamic wrap of the film in relation to the head. The
intention, however, was to aim for a 35µs curve.
--Scott
Scott D. Smith CAS
Chicago Audio Works, Inc.
On 6/14/2012 9:33 PM, Tom Fine wrote:
> Are you sure an early 50's Westrex recorder used SMPTE EQ? Wasn't that
> curve finalized later and those early Westrex machines used their own
> curve, as did early RCA machines? It's entirely possible that I am
> mis-remembering history!
>
> -- Tom Fine
>
> ----- Original Message ----- From: "Jamie Howarth" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Thursday, June 14, 2012 10:27 PM
> Subject: Re: [ARSCLIST] 35 mm again
>
>
>> That's correct. SMPTE eq.
>>
>> Sent from my iPhone
>>
>> On Jun 14, 2012, at 10:12 PM, Aaron Levinson
>> <[log in to unmask]> wrote:
>>
>>> That was what I recall. It was a non-standard speed by conventional
>>> audio standards.
>>>
>>> AA
>>>
>>> Sent from my iPhone
>>>
>>> On Jun 14, 2012, at 9:49 PM, Roderic G Stephens
>>> <[log in to unmask]> wrote:
>>>
>>>> If I read and convert correctly, 18 IPS.
>>>>
>>>> --- On Thu, 6/14/12, Steve Smolian <[log in to unmask]> wrote:
>>>>
>>>> From: Steve Smolian <[log in to unmask]>
>>>> Subject: Re: [ARSCLIST] 35 mm again
>>>> To: [log in to unmask]
>>>> Date: Thursday, June 14, 2012, 6:31 PM
>>>>
>>>> Tom and anyone else with the answer,
>>>>
>>>> At what speed were Everest's 35mm recordings made?
>>>>
>>>> Steve Smolian
>>
>
|