Apple and macam

For those interested in imaging and image processing with DSLR, CCD, webcam or film.

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Vapouriser
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Apple and macam

Post by Vapouriser »

Trying to use a 6 inch f8 evostar with macam but cannot see anything on the computer screen except glare where a planet should be. Using filters has not made any difference unlike the equivalent full moon which can be seen perfectly. I chose macam as the only other that would download itself was keith s which looked too complicated.! Is there something I can do please?
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dazcaz
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Post by dazcaz »

Is this the software to get webcams working on a Mac?
If so, I have only used Macam on a microscope and it worked very well indeed.
If you can see the moon, you should be able to see anything else bright enough for the webcam to detect.
Could it be something simple like you are not focussing correctly or aiming the scope right?
It's a lot easier finding the moon through a camera than it is a planet :)

What stacking software are you using? I want to get into imaging with my Macs, but can't get on with the software I have :(
I once came last in an astronomy competition.
I was awarded a constellation prize


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Vapouriser
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Apple and macam

Post by Vapouriser »

Yes it is the right software for apple. The problem with any stacking /processing software is that I do not have the time/patience or fir that matter brains to work it out. I once took a vista computer outside and used a large axe on it. Fortunately the apple works perfectly but Its not mine so I m not taking any chances! Now you mention focus I have found a secondhand crayford and will try that. Having got so close I cant give up now. Ta.
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Brian
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Post by Brian »

Sounds as if you are operating your camera in auto-exposure mode. I don't know macam but you should be able to "untick" auto and adjust the camera exposures using shutter speed, gain, brightness and gamma (but mainly shutter and gain). Set gain to about 40% then adjust shutter speed (exposure) until you start to see some sort of markings on the planet's disk. If macam has a histogram readout of image brightness you can use that to set your exposure very accurately. You need to borderline underexpose for image stacking, don't over expose or you lose detail in glare.

What happens with the auto setting is that you often get good results with the Moon, which fills the whole frame. The auto-exposure software makes a half-decent job of averaging the exposure over the whole frame as extreme values of brightness can be avoided.

In the case of a planet, which is a bright spot in an otherwise black frame, the auto exposure software can't cope with the brightness values at the two extremes (black =0, white = 255). It averages the two (lots of black pixels and fewer bright ones) to give an exposure which is still too great for the small object of interest. You need to get into manual mode on the camera so that you can make the exposure judgement more realistically :)

HTH,
Brian
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Vapouriser
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Macam

Post by Vapouriser »

Aha. I ll look into it. I know there is something else in macam which I was reluctant to try. Really dont get on with anything not steam powered but this hasnt looked too frightening yet. Thank you
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David Frydman
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Post by David Frydman »

It seems to be a similar problem to photographing the Moon with a compact digital camera in Auto or Program. The exposure is quite wrong, because the Moon's image is only a small part of the frame.
If I switch to Manual or Shutter speed priority, which is Tv for some reason on Canon Powershots then it is easy to get the correct exposure by just moving the shutter speed arrow.

I like the idea of taking an axe to a computer.
I wanted to destroy a laptop and looked up a video of somebody drilling multiple holes in it with a big drill.

I also thought of dropping it into a deep ocean trench. 10 kms should do it. But I suppose that would be considered polluting the environment.

Regards, David
Vapouriser
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Apple macam.

Post by Vapouriser »

The moonhas nt been a problem( yet). I just use filters. Wonder if I could hire myself out at parties furiously chopping up old vistas. Seriously though I have wondered what happened to Jackie Cottram if BackYard Moon. I know she had major surgery about 4 weeks ago but I have not heard from her since, not surprisingly perhaps. Dies anyone know if she s out if hospital? Jonathon
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