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aussie_bloke wrote: I tried yesterday to get a picture of the front yard from the sunlight but my camera is still not sensitive enough
gary wrote:This is a little off topic for this particular build, but the subject of the amount of light available caused me to think about Doug Pitt writing that sun light would be an ideal source but that he was always thwarted by that nice cool cloudy weather the enjoy in England.
Now here in Oz we have a surplus of bright sunny days, especially at this time of year. I have always wanted to try this out but my cameras have never been portable enough to try it out (I have to correct that some day).
So here's a challenge to Aussie builders - build an outdoors NBTV camera!
gary wrote:Which one? The FSS used as projector lamp, and with the other I used a 500w workshop type light.
I think if you tried to implement the brightness of a spring/summer day in Oz:
a) you would melt
b) you would go bankrupt from the effects of the "no carbon tax (sic) under the government I lead" tax...
harry dalek wrote:I did mean the the indoor light Gary Ok 500 watts yakes ! .
harry dalek wrote:The reflected light is the thing to measure not the sun or lamp i think..
harry dalek wrote:I see a sunny day is 100000 lux but is that pointing at the sun the sky
harry dalek wrote:- the amount
as it would have to change depending on the reflective surface ..depending on your light distance would that 500 watt light be the same as the sun shining off the toby jug illuminating that small area ...the reflective light measured might show its similar...don't know speculating...
harry dalek wrote:But sounds like out door nbtv is easier than indoor ?
Klaas Robers wrote:Troy,
just for fun: place a sheet of white paper on the Nipkow disc as a kind of projection screen. Then you will see the image of your subject. That will be dimmed in respect to the lamp and the three holed stone. This image should be focussed sharp on the surface of the Nipkow disc.
Then I see that you have lots of stray light on your Nipkow disc. Try to find a kind of black tube and slide that over the projector lens. In this way you may darken the path between the lens and the Nipkow disc. That will improve your contrast, at least make the black parts darker.
Then also screen the part behind the disc, the condensors and the photo diode or -transistor. The Nipkow has only one hole "open" at the time, so the amount of light passing the disc is very little. Then all stray light spoils the functioning of your photo sensor. So a closed box or a back cloth (Baird used that very frequently).
AncientBrit wrote:Hi Gary,
Yes I have all the recordings but as I explained they are a succession of bit maps and need some of my software to view.
AncientBrit wrote:The samples are NBTV line synchronous so there are always 64 samples per line
They are not WAV files.
AncientBrit wrote:Only publication was in the Newsletter, but not here on the forum.
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