Cartes Du Ciel - What sizes in the finder rectangle for a DSLR?

[swag72]

Just getting my astro PC sorted out, so have loaded Cartes Du Ciel onto it. I would like to set the FOV of my DSLR in the finder rectangle setting, but not sure what width and height to put in for a 1000D - Can someone let me know please if they have this already set up on their PC.

Cheers

[Merlin66]

The New CCD Astronomy Home Page

I'll look at the sensor size for you later, I think its 22mm x 16mm...

[jgs001]

the 1000d sensor is 22.2mm x 14.8mm

[swag72]

Thanks both.

[Sparrow]

I've just loaded CArt Du ciel as well and used the dimensions given above for my Canon 1000D, but the finder rectangle in the FOV is far too small. I'm not doubting the dimensions given and presume there must be something else I need to set to get the correct rectangle size. I would have thought it would need to know the telescope size and F number but I can't see anywhere to input this information. Could someone help me with this please.

Thanks

John

[themos]

From memory, CdC needs a rectangle's dimension in arcminutes. It's up to you to calculate this for your camera/scope combination, using CCDcalc or similar.

Or you could just take a picture, upload it to flickr in the astrometry group and then wait for astrometry.net to comment on it with the Field Size!

[Merlin66]

Yes, the width and height of the finder/ camera boxes in CdC is in Minutes of Arc ie 5 degrees = 300 minutes of arc.

Use the CCDCalc with your camera lens to find the FOV and transfer this data to CdC

[carpman]

i have just pumped details into CCDcalc and fov for a canon 1000d is in arc mins is 67.6 x 101.5

[Sparrow]

Thanks for that - yes I've put the details in CCD calc and got the necessary figures. It's a shame Cart Du Ciel doesn't actually show what units to use in the CCD dialogue box but it all makes sense now.

Carpman - don't forget, those figures you give will be specific to you camera and scope aperture/F stop.

Regards

John

[Merlin66]

It does...it's in the help menu.

[Sparrow]

It's in the help menu but it's not in the dialogue box - where figures are concerned it's usual to have a label with the box advising what units are being used. Numbers are meaningless without an indication of what the unit is -

arc seconds/minutes/mm/cm/pence/ohms/volts/light years/apples to the pound/grams/

Think of a graph with a line on it but no labels on the axis - the graph could mean anything