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In the market for a CCD imaging camera - what to get?


brainy

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Hello,

I started piggyback imaging from my backward recently and I enjoy quite a lot.

I live in Montreal which is severely affected by light pollution (population of around 4 million). I was able to image big objects like M31, but with very short exposures. I can't get past 15 seconds exposures at ISO 800 and f/4 with my Nikon 80-200 f/2.8 before the sky becomes completely washed out by light pollution.

I read about mono ccd cameras and narrowband imaging. I am really fascinated by monochrome imaging and would really like to try it. Plus using a Ha filter should allow me to image from my backyard without problem.

I can't get my head around my need in terms of CCD imaging camera. Could you suggest a good match for my equipment in the range of 1,500$? I want to image mainly deep-sky objects like M31. I was thinking of the ATIK 314L+ which seems to have received a lot of praise on this forum. I quite like Celestron's products and so I was thinking of the Celestron Night-cap 8300 as well.

Current equipment

Celestron Advanced VX

Celestron 6" Newtonian f/5 (750mm FL)

Orion StarShoot autoguider

Orion Shortube 80-T refractor (guiding scope)

I understand that my newtonian might not be the best imaging scope, but I would like to use it for now. I might get a small apochromatic refractor some time soon.

Thanks and I hope you are not too bored with these "what equipment should I get" questions!

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It's all about the field of view and plugging your scope /  potential CCD combo into such a calculator is a good way to do it. My initial thoughts are that using a scope with 750mm and the 314L+ you are really going to end up having to look at smaller nebs and / or doing mosaics, many are really quite sizeable. For example at 330mm and a larger chip than you are looking at I still do a fair few mosaics. 

Good luck in your quest, choosing a CCD is not easy!

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Hello,

I started piggyback imaging from my backward recently and I enjoy quite a lot.

I live in Montreal which is severely affected by light pollution (population of around 4 million). I was able to image big objects like M31, but with very short exposures. I can't get past 15 seconds exposures at ISO 800 and f/4 with my Nikon 80-200 f/2.8 before the sky becomes completely washed out by light pollution.

I read about mono ccd cameras and narrowband imaging. I am really fascinated by monochrome imaging and would really like to try it. Plus using a Ha filter should allow me to image from my backyard without problem.

I can't get my head around my need in terms of CCD imaging camera. Could you suggest a good match for my equipment in the range of 1,500$? I want to image mainly deep-sky objects like M31. I was thinking of the ATIK 314L+ which seems to have received a lot of praise on this forum. I quite like Celestron's products and so I was thinking of the Celestron Night-cap 8300 as well.

Current equipment

Celestron Advanced VX

Celestron 6" Newtonian f/5 (750mm FL)

Orion StarShoot autoguider

Orion Shortube 80-T refractor (guiding scope)

I understand that my newtonian might not be the best imaging scope, but I would like to use it for now. I might get a small apochromatic refractor some time soon.

Thanks and I hope you are not too bored with these "what equipment should I get" questions!

With your  current set up finding a CCD large enough to get the whole of M31 on the sensor  is going to be expensive to say the least. If you can achieve focus with your DSLR and the scope in prime focus ( DSLR mounted directly onto the scope and using the scope as a telephoto lens ) the cheapest options are to use either a Nebula CCD filter such as the Baader UHC-s L Booster or the IDAS LPS -V4 filter as  NB  LP filter for colour imaging or using a 2" Ha filter to reduce the LP, however these options are only viable if your camera is modded which I suspect yours is not so it is back to square one. You may wish to consider using a modded Canon camera with the option of using various Astronomik Clip Filters should you wish to spend the money .

A.G

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I currently have a Nikon D7000. I will test it out on dso when the weather is a little more clement. Buying a modded (Canon) DSLR is definitely a good way to go but I would be afraid to get limited at one point and I'm not sure how many people are willing to buy astro-modded cameras on, say, eBay. I found http://cheapastrophotography.vpweb.co.uk which seems to have a good reputation on this forum.

Going back to CCDs, what do you think of the QHY9M (4/3 sensor size!)? It retails for about 2,000$ with filter wheel.

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i dont know anything about the nikons but my eos 1100d is not modified and i use the 2" Baader UHC-s L booster filter and it works a treat for lp and it does give better contrast.

With an unmodded camera you only get about 15~20% of the available Ha through, with a UHC-s filter the LP will be drastically reduced but the overal colour balance of the target will be predominantly in favour of blue or teal.

A.G

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workI currently have a Nikon D7000. I will test it out on dso when the weather is a little more clement. Buying a modded (Canon) DSLR is definitely a good way to go but I would be afraid to get limited at one point and I'm not sure how many people are willing to buy astro-modded cameras on, say, eBay. I found http://cheapastrophotography.vpweb.co.uk which seems to have a good reputation on this forum.

Going back to CCDs, what do you think of the QHY9M (4/3 sensor size!)? It retails for about 2,000$ with filter wheel.

From what I have seen on the web the Nikon 7000 is capable of producing good results unmodded. My Canon DSLRs are 1000d modded , 1100d unmodded and 1100d modded plus a few Cooled CCDs and there is a dramatic difference in response to the Ha between the Modded and Unmodded cameras, the CCDs are in a different class all together. You may also wish to try an IDAS P2 filter, if things do not work out you can always keep it for future use  with a CCD or sell it at very little loss, these filters are quite pricy in the UK.

A.G

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Hi Brainy

A possibility might be to swap your current imaging and guiding scopes. It might seem a bit of a strange thing to do but I can't think of any reason why you couldn't image big targets with your 80mm whilst guiding with the newt! Or failing that, you could add a 9x50 finder or guide scope to the 80mm  and image with that. I presume your 80mm is an achro so would be susceptible to fringing but I think there are ways to minimise that (from what I've read). A good lp filter can help with the lp or you could try narrow band.

Just some ideas :)

Louise

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Forget galaxies in Ha only. Ha is interesting in galaxies only because it picks out a few blobs of star formation in most of them. An Ha image of a galaxy doesn't often look much like a galaxy and would rarely be rewarding. Added to colour it does enhance an image though.

It is emission nebulae which respond well in Ha and these tend to be large, so the biggest sensor and the shortest focal length are often ideal. At 750mm I would't  go smaller than the Atik 383 really.

It really isn't logical to use anything but a mono chip for narrowband but it can be done, slowly and painfully!

Olly

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Forget galaxies in Ha only. Ha is interesting in galaxies only because it picks out a few blobs of star formation in most of them. An Ha image of a galaxy doesn't often look much like a galaxy and would rarely be rewarding. Added to colour it does enhance an image though.

It is emission nebulae which respond well in Ha and these tend to be large, so the biggest sensor and the shortest focal length are often ideal. At 750mm I would't  go smaller than the Atik 383 really.

It really isn't logical to use anything but a mono chip for narrowband but it can be done, slowly and painfully!

Olly

Hi Olly

The OP said 'DSOs like M31' - I presume he/she wants to image nebs too! He says he's read up on NB imaging so he/she probably realises that only certain targets are suitable but, like me, has a severe lp problem.

Louise

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Hi Olly

The OP said 'DSOs like M31' - I presume he/she wants to image nebs too! He says he's read up on NB imaging so he/she probably realises that only certain targets are suitable but, like me, has a severe lp problem.

Louise

I know, but DSOs like M31 are going to be galaxies like M31, hence my response.

Olly

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I moved into narrow band for the same reasons.

A mono camera with 7nm Ha filter is the way to go. It cuts through light pollution and you can still image during full moon.

I bought an entry level cam with a small chip (starlight H9) because it was all I could afford, there are targets that fit in the field of view and plenty of them (spring is a little barren though).

Most galaxies would fit, with the exceptions of a couple of large ones, replace the Ha filter with a Light Pollution filter and you should get some ok results on galaxies in the spring.

Ant

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ollypenrice, on 28 Aug 2014 - 5:11 PM, said:ollypenrice, on 28 Aug 2014 - 5:11 PM, said:ollypenrice, on 28 Aug 2014 - 5:11 PM, said:ollypenrice, on 28 Aug 2014 - 5:11 PM, said:ollypenrice, on 28 Aug 2014 - 5:11 PM, said:

At 750mm I would't  go smaller than the Atik 383 really.

Bang on the money there! The 8300 chip is the only one (bar the 460 or new Atik 9.0) thats gives a wide enough view at that FL .

However, the bigger the chip - the bigger a test it is for your optics. So you will need to factor in some correction, or even pay attention to the actual mechanics of your focuser (and I understand that the celestron focuser is basic at best). Fortunately, with a 6" tube you can swap out the focuser for something more mechanically sound - an option I didnt really have with my 5" tube, so I ended up having to make extensive modifications to the stock focuser.

Point is, if youre paying for a lot of CCD pixels - you want to be able to use as many of them as possible (no cropping).

Edit:

Also, NB is a good way to go (even for a beginner) - I find that I do a lot more nebula work than anything else as there is always something available at least 9 months of the year. Ha 7.5nm was my first filter, and you can do an awful lot with one of those.

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I was going to suggest you get the Atik383L or similar as I agree with what Olly says.  

Alternatively the Atik314 is a really great camera as you have already said, you could get yourself a really small APO refractor for when you want to image the larger objects,  you can also add a focal reducer.  I wish I had realised this before I bought my Atik383L, I now have both cameras and 3 telescopes depending on my target.

Had I thought of using a small refractor I might not have needed to get the Atik383L but you live and learn.

I live in a LP location in the suburbs of London, and with a LP filter I can image the brighter objects from home, but narrowband is needed for other objects.  

Carole 

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from what i gather you wont get all of m31 in your field of view with any but the atic 11000 ccd with your scope.

look here to see what you will get just put in your scope and ccd you want and then pic object       http://www.skyatnightmagazine.com/field-view-calculator

FYI, there's a newer version of this FoV calculator which includes newer camera versions (for example the older one doesn't include my Canon 6D), it's here: http://www.12dstring.me.uk/fovcalc.php

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I was going to suggest you get the Atik383L or similar as I agree with what Olly says.  

Alternatively the Atik314 is a really great camera as you have already said, you could get yourself a really small APO refractor for when you want to image the larger objects,  you can also add a focal reducer.  I wish I had realised this before I bought my Atik383L, I now have both cameras and 3 telescopes depending on my target.

Had I thought of using a small refractor I might not have needed to get the Atik383L but you live and learn.

I live in a LP location in the suburbs of London, and with a LP filter I can image the brighter objects from home, but narrowband is needed for other objects.  

Carole 

Hi Carole,

You are quite correct to a large degree but personaly speaking for me to get the whole of M31 on to the 314L+ I have to either use my Canon 200 F2.8 L or use a 0.6 X FF/FR on the WO ZS 71 with the penalty of imaging @ about 5.2 arcsec/pixel which is not ideal. I still can not get myself to part with nearly £2000.00 for a 460ex .

Regards,

A.G

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Thanks everyone for the advice! Super useful  :grin: I do think that a mono ccd and NB imaging is the way to go as I do not own a car, making it hard for me to get away from LP. I am given to understand that imaging with RGB filters would not be affected by LP? Why is that? Street lights emits light in those colours, no? Does the RGB filters only allow a narrow wavelength in these colours?

I was going to suggest you get the Atik383L or similar as I agree with what Olly says.  

Alternatively the Atik314 is a really great camera as you have already said, you could get yourself a really small APO refractor for when you want to image the larger objects,  you can also add a focal reducer.  I wish I had realised this before I bought my Atik383L, I now have both cameras and 3 telescopes depending on my target.

Had I thought of using a small refractor I might not have needed to get the Atik383L but you live and learn.

I live in a LP location in the suburbs of London, and with a LP filter I can image the brighter objects from home, but narrowband is needed for other objects.  

Carole 

I think I am going to follow this advice. I will most probably get a William Optics ZS71 (http://www.canadiantelescopes.com/Shop-By-Brand/Telescopes_12/William-Optics-Zenithstar-71-Doublet-ED-APO_4.html#.VAHZP8I3dSU) or Explore Scientific 80ED APO Triplet and play with my Nikon D7000 for a while until I feel confident with my tracking/autoguiding skills. Then I would go for a Atik314L+ (with the focal reducer, I would get a resolution of 3.98"/pixel which might be a little high). 

I am still tempted by the QHYCCD QHY9 with automated filter wheel for a little over 2,000$.

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Thanks everyone for the advice! Super useful  :grin: I do think that a mono ccd and NB imaging is the way to go as I do not own a car, making it hard for me to get away from LP. I am given to understand that imaging with RGB filters would not be affected by LP? Why is that? Street lights emits light in those colours, no? Does the RGB filters only allow a narrow wavelength in these colours?

I think I am going to follow this advice. I will most probably get a William Optics ZS71 (http://www.canadiantelescopes.com/Shop-By-Brand/Telescopes_12/William-Optics-Zenithstar-71-Doublet-ED-APO_4.html#.VAHZP8I3dSU) or Explore Scientific 80ED APO Triplet and play with my Nikon D7000 for a while until I feel confident with my tracking/autoguiding skills. Then I would go for a Atik314L+ (with the focal reducer, I would get a resolution of 3.98"/pixel which might be a little high). 

I am still tempted by the QHYCCD QHY9 with automated filter wheel for a little over 2,000$.

3.98 is a little high but bear this in mind; I bet more APODS have been taken with Takahashi FSQ106 astrographs and Kodak 11meg chips than with any other combination and that is running at 3.5 arcsecs per pixel. Here's one of Tom's; http://apod.nasa.gov/apod/ap120828.html  There are planty more by Rogelio Bernal Andreo and many, many others.

Olly

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