[pure-silver] Re: No More Below the Lens Polymax Filter Kits?
- From: Don Sweet <don@xxxxxxxxxxxxxxxx>
- To: pure-silver@xxxxxxxxxxxxx
- Date: Thu, 05 Feb 2009 11:06:10 +1300
High intensity LEDs covering the bluer parts of the specturm have been on
the market for the last 10 years or more. I wonder why they cannot provide
an easy substitute for enlarger lamps; they are apparently stable, with very
low power consumption and virtually heat generation, and last for ages. A
switchable bank of mixed frequency LEDs would seem to be a natural match for
VC paper. Has his been done, or do LEDs present some fiendish design
problem in this context?
Don Sweet
----- Original Message -----
From: "mail1" <mail1@xxxxxxxxxxxxxxxxx>
To: <pure-silver@xxxxxxxxxxxxx>
Sent: Thursday, February 05, 2009 10:34 AM
Subject: [pure-silver] Re: No More Below the Lens Polymax Filter Kits?
> There are three versions of Zone VI VC heads. The first version used
> separate large transformers, and Variac controls for each tube. This VC
head
> is very bright with short exposure times producing a paper ES 1.43, Grade
0
> to ES .60 Grade 5. (ISO 100 equals ES 1.0) I use this unit with a Metrolux
> Timer that adjusts for lamp output accurately. Using large transforms
> produces high output from the tubes.
> The second version used smaller transformers and electronic circuits to
> control output. I suspect you might have this version. This design could
> have issues with output and control. Generation 3 uses LED light sources
> unfortunately I have not had an opportunity to use this model.
>
> I also use the Aristo VCL4500. My unit has adjustments for both the green
> and blue lamps producing a paper ES 1.40 Grade 0 to ES.40 Grade 5.
> The Aristo tubes use colored glass that filters the frequency to a narrow
> spectrum where as the first generation of Zone VI uses internal phosphor
> coating only there for the frequency of light is a broader spectrum. This
> broad spectrum reacts differently, and appears brighter to our vision.
>
> I also use a durst 138 Condenser enlarger with Ilford filters the filters
> produce range from ES 1.38 to ES .37 Changing the voltage on the bulb does
> create subtle differences. I use a Metrolux timer with a Variac to control
> the voltage of the bulb. I really like the Durst although I find it
sometime
> difficult to produce ideal negatives for a condenser enlarger hence the
> reason for having the cold light systems.
>
> Low pressure mercury vapor lights have a narrow non uniform spectral
energy
> output. Photographic paper is optimized for the use of filtered
incandescent
> light which has a very different spectral energy distribution. This
> difference does show up in subtle ways.
>
>
> Jonathan Ayers
> [mail1@xxxxxxxxxxxxxxxxx]
>
>
>
>
>
> -----Original Message-----
> From: pure-silver-bounce@xxxxxxxxxxxxx
> [mailto:pure-silver-bounce@xxxxxxxxxxxxx] On Behalf Of john stockdale
> Sent: Wednesday, February 04, 2009 3:42 AM
> To: pure-silver@xxxxxxxxxxxxx
> Subject: [pure-silver] Re: No More Below the Lens Polymax Filter Kits?
>
> Eric, I have a Zone VI VC head that I don't want, but I wouldn't
> recommend it for various reasons. I can give you details if you're
> interested.
> Regards, John
>
> =====================
> Eric Nelson wrote:
> > Thanks John I'm already on the lookout and have added aristo and zone
> > vi to my saved searches on ebay. I'll have a chat w/Kodak tomorrow
> > and see what the story is on the filters.
> > Eric
> >
> >
> > ------------------------------------------------------------------------
> > *From:* john stockdale <j.sto@xxxxxxxxxxx>
> > *To:* pure-silver@xxxxxxxxxxxxx
> > *Sent:* Tuesday, February 3, 2009 11:59:18 PM
> > *Subject:* [pure-silver] Re: No More Below the Lens Polymax Filter Kits?
> >
> > The Aristo VCL4500 with an RH Designs Stop Clock Vario is a sweet, if
> > expensive, solution.
> >
> > John
> >
> > Eric Nelson wrote:
> > > Man, and the list here was just touching on this subject recently
> > too. So I did my online searches and have come up empty handed from
> > Freestyle to Adorama to B&H to ebay.
> > > Now /that's/ sad. At least the filters are still available and I
> > can cut them down for the holders which I still have. Ilford's
> > filters stink as I've been using them a month or so. The contrast
> > jumps dramatically between 1/2 grades and exposure is nowhere near
> > similar from one filter to the next using /*their*/ frakkin' paper.
> > Maybe I just "owe myself" a VC head and be done with it.
> > >
> > > Sigh.
> > >
> >
> >
>
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