1. XAXP Demo - JohnS
2. Explanation of Color Temperature - RickG
From Jeff re color temperature:
After Rick's dissertation on this subject I asked why colour
temperature is important. The following extracts from Encarta and
Britannica encyclopaedias may help those interested.
Firstly the word temperature follows from theoretical physics in
relation to temperature measured on the absolute scale and expressed
as degrees Kelvin.
From Encarta: "At a given temperature, a blackbody emits a definite
amount of energy at each wavelength, but the energy carried by the
radiation is not distributed evenly across the wavelength range; the
proportion of energy carried by shorter wavelengths increases as the
temperature of the source increases. This is in accordance with Wien's
Law. ëmax T = constant, where ëmax is the maximum wavelength, and T is
the surface temperature in kelvins (K)."
An important application is for colour balance in colour photography.
From Britannica:
"Colour film reacts to all hue and tone differences, including the
prevailing light colour. A film recording approximately natural
colours in daylight reproduces scenes photographed by tungsten light
with a reddish overall tint--because this lighting is richer in red
rays than is daylight. This spectral balance of different "white"
light sources may be rated numerically by the colour temperature--a
concept of theoretical physics that, with tungsten lighting,
corresponds roughly to the absolute lamp-filament temperature. Such
absolute temperatures are expressed in kelvins (K). The higher the
colour temperature the richer the light is in bluish and the poorer it
is in reddish rays and vice versa. Average daylight is rated at about
5,500 K, the light from an overcast sky from 6,500 K up; the colour
temperature of tungsten lamps ranges between 2,600 and 3,400 K.
To ensure correct "white-light" colour reproduction with different
types of lighting, the sensitivities of the three film layers must be
matched to the colour temperature of the light. Colour slide
(reversal) films are therefore made in different versions balanced for
faithful rendering either with 5,500 to 6,000 K light sources (such as
daylight or electronic flash) or with specified tungsten lighting
(3,200 to 3,400 K).
Such accurate film balance matching is less vital with negative colour
films since the colour rendering of the print can be modified during
colour printing. "Universal" amateur negative colour films are usable
with any light, from tungsten to daylight. For high quality,
professional negative colour films are still preferentially balanced
to either daylight or tungsten sources."
From Jeff:
All a bit confusing because of the common description of yellowish or
reddish pictures as being warm and bluish as being cool. Thus to cool
down tungsten lighted scenes to obtain more "natural colours" in a
colour slide photograph a blue filter is used on a camera and to warm
up a scene as on a rainy day, a yellow filter is used. A colour
temperature meter serves to indicate filters to be used for such
subjects. To impress and cause confusion ask what the colour
temperature was when a photograph was taken.
3. ULead PhotoImpact5 - TrevorF.
Version 7 has been published and version 5 has now been published for
free on Australian PC User October 2002 magazine just arrived in my
mailbox.
4.a, Addressing 0,,,,,,,,0
4.b. Stopping DOS task -- the foregoing questions were raised by JohnS
on behalf of JohnA.
After discussion the meeting agreed that there was not quite enough
information in the questions and JohnA would need to ask these at a
meeting.
5. Good results with scanning transparencies - RodB
Rod showed the printed results of scanning transparencies and
adjusting and extending the information obtained. The tools used were
Epson 1240U scanner with film attachment, Canon 4310SP printer with
photocolour cartridge and Paintshop Pro 7.4.
Regards, Rod.
6. Noisy fan - PeterH
Peter said that when he switched on his 3-year old PC the fan on the
power supply unit made a loud whirring noise. After about 5 minutes
or so the noise stopped. He was told that a new fan at the markets
costs about $20 but a complete new power supply unit with fan could be
obtained for $30. It was also suggested that he check the tightness of
the screws attaching the power supply unit and fan to the computer
case.
Peter was also concerned that he had missed episode 2 of The Forsyte
Saga and asked if anyone had recorded this episode as he is desperate
to borrow the tape. No one at the meeting had such a recording. Peter
can be contacted on 6161 3864 if some kind soul is able lend him a
videotape of the second episode..
7. XP firewall - PaulH
From MichelleH:
The following are a few words on Item 7. XP firewall - PaulH.
7. XP Firewall. Paul H requested advice on whether the firewall
that comes as part of Windows XP is well-regarded, or is it preferable
that a dedicated firewall application like ZoneAlarm or Tiny Personal
Firewall.
John S advised that the Windows XP firewall is a one-click either ON
or Off firewall that is not configurable, suitable for the beginner
user, however the dedicated firewall products are configurable and
provide a higher level of protection. General opinion was that it is
better to use the separate firewall applications.
8. Scanning/printing 35mm negatives - Moby
This is the result of some tests done printing scanned black and white
35mm negatives using my Canon BJC 6200 printer.
(a) Using 'greyscale' ie the black ink cartridge, did not give the
best results. The 'colour' was spot on - a lovely black, but the
detail was lacking and it showed grain. Using the full range of
cartrides gave the best detail and lack of grain. The best results
were obtained using the six 'photo' carts rather than the four
'colour' ones. I put this down to the fact that with the black only,
only the black printhead was in operation, while treating the
picture as a colour one brought in to play all the print heads with
many more nozzles laying ink.
(b) Colour casts became a problem in printing. As a b+w photo, I
wanted the blacks to be black and this was not the inevitable result.
I found that much depended on the brand of paper used. I tried
four different ones. One came out with a blue cast, another with
a green cast, the third with a very slight magenta one. The fourth
(Epson Photo Paper) was just right. The print looked like a b+w
one. The same settings were used for all.
This reinforced for me the necessity to do some experimentation
with photo types, with paper types and with printing modes in
order to get the most pleasing results to me.Then to stick
with this. I print all photos with the 'six pack' photo carts, at the
finest print quality. I have standardised on Kodak satin paper for
colour and Epson photo for b+w. There was sure some paper waste in
getting to this position but from here on all should be plain sailing.
9, Task scheduler - Derek
Without any conscious action, Task Scheduler Service had become
disabled. Hence, not only were the scheduled tasks not being
performed, but Norton Anti Virus Live Update was not occuring as it
depends on the Task Scheduler being enabled.
Several possible actions to enable the TSS were suggested; none of
them was effective. For an unconnected reason I used System Restore to
get rid of some recent downloaded/installed Windows Critical Updates (
some part of which was causing a complete system "freeze" roughly
every 5 minutes!!!) and the TSS is again enabled - and no freezing.
With System Restore I can do without sliced bread.
Cheers, Derek
10. EZ - RodS
11, If time was available (there was) AlanV discussed various aspects
of his recent trek to remote areas of Australia.
The item was probably incoherent as I was still more spaced out than
usual after arriving home late Monday.
It was meant to be a whimsical filler about new opportunities using
technology in the bush - and new problems: - GPS connected to Notebook
enabled correct determination of position after blowing it with GPS &
paper map (blush) and confirming unreliably guessed position using
normal (map/compass/terrain) methods in unfamiliar relatively
featureless very remote country - N/b was invaluable storage device
for digital camera images,*but*
(a) Better to learn to use camera *before* leaving home!
(b) No camera can compensate for incompetent composition!
(c) Use of n/b severely restricted by $99 Invertor used for getting
240V from (2nd) car battery being more picky than fridge as battery
voltage dropped when vehicle stationary for several days. The n/b 2
hour batteries don't last long in such circs! [aside: IMHO *all*
vehicles travelling in remote areas should be fitted with a dual
battery system]
(d) If using a computer to store images, it is a good idea to install
some software which allows said images to be manipulated - or at
least viewed!
(e) The posher the camera and the more ignorant the user the more disk
space is needed [particularly if failed point (d) :-( ]. This can be
a problem if using an old n/b rather than expose new one to the rigors
of travelling in harsh conditions.
(f) It is a good idea to take *all* reasonable i/o devices when
travelling, particularly if one's n/b has neither a floppy nor a CDROM
drive!
In this case I took my PCMCIA-connected ZIP drive & (of course) my
PCMCIA Flash RAM connector, but neither were useful in trying to
scrounge missing s/w [(d) above] from friends in Perth mid-trip.
Either of my options left home, network and modem cards, would have
done the trick [and also allowed xfer to burn a CD or two to relieve
space pressure on HDD and limited supply of ZIP disks]. I did take and
use an old Canon BJ-30 printer but that was an unnecessary
extravagance in this case.
Summary: Problems were an interesting change from usual problems in
such travel [where are we? how much water to carry? is this water
drinkable? can we avoid getting bogged? etc]
Alan posted me an excellent binary .jpg showing him at the back of his
vehicle typing notes about his trip that he can share with the C&C
meeting.
I've not included it here because one shouldn't post binaries to
newsgroups and the list complains about it too even though it was
241k.
[Original was too big as was 2272*1704 and much too big to email]
Location was circa 400km east of Newman, WA == remote.
====================
Regards, Trevor
Date: Wednesday, September 17th,2002
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Go ahead and rock the boat! The only people who will care
are the ones who can't swim.
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