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Old 09-06-2016, 03:07 PM
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Pixel size question

When a star is imaged and say it's just on 1 pixel and the exposure is long, do you get a bleed over to 8 surrounding pixels?
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Old 09-06-2016, 03:33 PM
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Yes, on just about all detectors that amateurs or pros use if the exposure is long enough (which does not need to be long at all).
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Old 09-06-2016, 03:41 PM
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Thanks Steve, I'm trying to work out which ccd camera to get, seems an impossible search!
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Old 09-06-2016, 03:42 PM
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Most sensors have what is called Anti-Blooming Gates. Although a pixel can saturate, these blooming gates give anywhere between 100-2000x times the saturation level before they start bleeding into surrounding pixels.
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Old 09-06-2016, 03:42 PM
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See details in this thread: http://www.iceinspace.com.au/forum/s...d.php?t=146137
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Old 09-06-2016, 04:30 PM
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Quote:
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Thanks Steve, I'm trying to work out which ccd camera to get, seems an impossible search!
what scope(s) are you using?
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Old 10-06-2016, 12:45 PM
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what scope(s) are you using?
10" newt on a neq6
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Old 10-06-2016, 12:59 PM
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You want to arrange it so that stars fall on a few pixels rather than just one. To do that in typical seeing conditions, your scope would work well with any DSLR type camera, or an astro camera based on an 8300, a 694 or possibly even a ZWO1600 if you are adventurous.

you will need a coma corrector, whatever camera you choose.

Last edited by Shiraz; 10-06-2016 at 01:18 PM.
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Old 10-06-2016, 10:09 PM
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Thanks Steve, I'm trying to work out which ccd camera to get, seems an impossible search!
Sorry, can't really help you because it's very much down to what you want to do with it.

Nevertheless, modern DSLRs are pretty good all-rounders for starting out. You can do great deep sky shots and using them in video mode you can do nice planetary imaging as well. If you're looking for an inexpensive way into the art/science without clear specific goals yet beyond "I want to do astrophotography" that's the way to go imho.
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Old 11-06-2016, 08:14 AM
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10 inch Newt, what F ratio - F5? That would make it 1250mm focal length.

At that focal length just about camera works fine. Sony 694 4.54 microns. KAF 8300 5.4 micronsKAI1100 9 microns , KAF16200 6 microns, KAF16803 9 microns.

I think you chose more on the field of view and the QE (sensitivity) of the CCD and the cost. CCD cameras are very expensive.

Those are the names of the sensors I listed and they are used in various brands like SBIG, FLI, Starlight Express, Apogee, QHY, Moravian, Atik.

The less expensive brands are Atik, QHY, Moravian and the entry level SBIGs. Starlight Express are the next cheapest and then the others.

The ASI1600 may be good too but its new to the market and is probably going to be used in a different way to the others so you may not want to be part of that learning curve when starting.

A QHY9 seems popular, that uses the KAF8300 sensor which is the most popular sensor and is pretty versatile for many scopes.

Greg.
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Old 11-06-2016, 08:23 AM
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Thanks Greg At the moment I'm use a 1100d modded and feel it's time to move up.
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Old 11-06-2016, 08:37 AM
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A camera with 6 micron pixels will give you a sampling of 1"/pixel, 9 micron will get you to nearly 1.5"/pixel. On the EQ6 I would suggest either going with larger pixels or a camera with smaller pixels that you can do effective 2x2 binning. This is more important for monochrome as when you start binning with a One Shot Colour (OSC) they become monochrome.

If you wanted a cheaper way of getting into the market, the ASI1600-Cooled OSC is basically just a cooled DSLR.
http://www.bintel.com.au/Astrophotog...oductview.aspx

At $1,500 it is a bargain compared to most of the other CCDs on the market. As Greg says however, they are typically being used differently to most other CCDs as well and are very new on the scene. Being a OSC it does not need more filters so the $1,500 is all you will need. Moving to a monochrome is a LOT more expensive as you need to buy a filter wheel and filters and the camera is also more expensive.
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Old 12-06-2016, 09:26 AM
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Personally I'd go the ASI1600 and ride along the development path with Glen, Lee and Ray on this baby. I think they'll arrive at a good spot sooner or later. You're also using a similar scope to Ray so that will help with advice and likely results.

All the questions about which filter, what size, which filter wheel, which driver, what settings are all very topical at the moment so you'll get lots of support. You'll be part of a little club - the ASI Musketeers!

Also very short exposures really excludes the difficult part of astrophotography which is accurate tracking. It really takes the pressure off the hard bits.

Whether you go mono and used filter wheels and filters or go one shot colour is up to you but if you are ready for a step up you should go the mono as its more flexible, allows you to enter the realm of narrowband imaging.

Some of the filter wheels and filters are not that super expensive but being limited to OSC you may end up wanting to upgrade and taking a loss on the resale so you are not much better off.

Greg.
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