Posts Made By: Maurice Clark

Hi Rob,

I used a 416 for several years and they make a nice imager to start CCD imaging with. I know what you mean about the manual, however they are not that difficult to use.

First a few questions. What sort of telescope would you be using it on? Do you have a laptop or can you get a computer close to the scope? Did the camera come with a SCSI card or PCMCIA card?

When you start imaging, I would suggest that you skip the colour filter wheel initially. B&W is much simpler. Save colour imaging until you have some experience.

There are several websites that offer useful hints on how to start CCD imaging. Here is one that is aimed at the 416. You can also subscribe to the MAPUG uses group. They have a LOT of expertise there.

http://easyweb.easynet.co.uk/~chrish/416_ig.htm

Regards,

Maurice

And I thought Minnesota was cold!!!! 8O 8O

Maurice

Hi Kevin,

You can add another oooops to that list that shows the hipocracy of the USA. Over the weekend there was a report that a USA soldier had killed a very well-known and popular person in Romania as a result of driving while drunk.

What did that paragon of truth and justice do? Spirited the soldier out of the country as fast as they could, so he would not have to face court for his crime. One can only wonder what would have been the reaction in the USA if the opposite had happened.

What a great way of winning friends around the world. And so many in the USA wonder why the USA is disliked overseas.

Regards,

Maurice

Hi Gianluca,

First up, don't dispair, there great images will come with experience.

For focusing, you do not need anything very wide to produce diffraction spikes. I get good spikes from the spider for a normal newtonian. It is possible you did not see them because your star was too faint. Try picking a bright star and using a sub-frame that has the star out of view but the diffraction spikes in view. Your other alternative is to use a mask over the objective with 3 holes. (Hartman mask) When your image is out of focus, you will see 3 images. When in focus you will see one. Some people make one of the holes in a triangular shape so that a diffracton spike is produced. I have never bothered.

I am surprised you could not find a suitable guidestar, especially at f/3.3 an in the M42 region. What sort of exposure were you using?

For processing, I think you would want something better than CCDOpps. There is a wide variety of software available. If you have a win98 machine, MegaFix is quite good, (does not work with winXP) CCDSoft is not bad, although limited. IRIS is freeware that I have not tried. There are many others at various prices.

When it comes to adding or averaging, often it is personal choise. Also some images give better results when added, others when averaged. I often do both (and median) and then see which one looks best.

Hope this helps.

Maurice

Hi Ben,

The theoretical resolution of a telescope is given by:

a" = (0.25 x wavelength in microns) / mirror diam in metres

Green light has a wavelength of about 500 nm or abour 0.4 microns, so using a 1m telescope (don't we wish!!!) the resolution would be 0.1 arc seconds.

Hope this helps.

Maurice

Hi Tom,

Interesting that they project the return to surplus in about 2012. I wonder how that will be managed?

Regards,

Maurice

Hi,

I find this hullabaloo over the shroud to me interesting. I mean, all of the people proclaiming that the shroud is genuine are Christians... right?

Well.... assuming that Christians read their Bible, then surely they would know from that, that the shroud cannot be genuine. Reading the eyewintess accounts, we read that several cloths were used to wrap the body of Jesus and that his head was covered with a napkin. Therefore any person who believes the Bible, and I would assume that would include Christians, would know that the shroud is a fake.

Sorry to confuse the issue with facts!!

Cheers,

Maurice

Hi Ansuman,

It would help if you let us know the type of observations you aim to make. ie visual observing is a LOT more forgiving on mounts than photographic or CCD.

For visual observing I agree that you could use a G-11 or similar. However if you aim to do photography with the 12", you would probably need something bigger like a Titan.

Regards,

Maurice

Hi Bill,

How quickly some forget! Hey! I was rolling in the PRP mud with the best of them from the start!!!! 8O

Some of us still remember the good ol' days! 8)

You should visit there more often! If nothing else, you learn to apreciate the gentiel nature of this forum!

Cheers,

Maurice

Rosetta photo contest details announced!

http://www.spaceref.com/news/viewpr.html?pid=16246

I am not eligible, but some others here should be. Also it should be fun to watch the craft as it swings past.

Cheers,

Maurice

PS what's the bet on clouds that night!!