How to choose the right camera?

[Edward Dewolf]

I have been stargazing for a while now using my Skywatcher 150/750 PDS Explorer, I have a HEQ-5 PRO tracking mount and will get a autoguiding setup soon

I would like to start imaging and buy me a dedicated camera.  I have no idea what to look for though, and there is soo much choice.  Can anyone help me with finding the right telescope that will allow me mainly to image DSO's and if possible planets sometimes too (is that actually possible a camera for both? )  Where do I start?

Thank you !

Edward

[dannybgoode]

The best place to start is to decide a budget and whether you want a mono (meaning you’ll need various filters to shoot colour) or what is known as a one shot colour camera which will take colour photos.  There are advantages and disadvantages to both. 

Have you read ‘Making Every Photon Count’ yet? If not I’d get a copy of that before you buy anything as it’ll give you a good insight into what’s available. 

Once you know roughly what route you’re taking and how much you want to spend let us know and we’ll soon talk you into doubling your budget  

[vlaiv]

For start, why don't you just use your current scope for imaging?

You mentioned getting the auto guiding setup? If you get your self CMOS camera for auto guiding - you can use that for planetary imaging with suitable barlow lens. Something like ASI120 would be low budget option or ASI224/ASI385 as a bit future proof option but more costly (actually I think that ASI385 is the best color planetary cam that you can get at the moment).

Like said above, choose between OSC and Mono for main camera, and decide on your budget. There are quite a bit options available so deciding on type of camera and budget will help.

[carastro]

The scope you already have will do good images.  If you have a 9 x 50 finderscope with it you can use that as a finderscope, just need to add an adapter and small guide camera. 

Just need to decide on the imaging camera.  

As stated above there are a number to choose from, some more expensive than others, some giving better results than others, and some being more versatile.

1.  DSLR (cheap) large sensor, needs modifying, will give instant colour, but is not cooled so noisier and makes taking dark calibration frames more of a pain.  

2. Cooled  dedicated astronomy camera.  Dark calibration files can be taken and re-used. 

Two Types on the market.  CMOS and CCD, each come either as one shot colour (OSC) or mono.

OSC: As stated gives instant colour but is less sensitive than a mono camera.  Costs the same as a mono camera but you don't have to buy additional filters and filterwheel.  More straight forward to post process.

Mono:  Much more sensitive giving sharper detail, but needs a filterwheel and filters, and has a bigger learning curve.  Can also be used for narrowband imaging in LP locations.  

CCD cameras cost more than CMOS

CMOS cameras, use lots of shorter exposures but you need loads of them.  Advantage is they are cheaper than CCD avoid long exposure risk of plans flying through and clouds, reduce guiding problems because of short exposures, but need a high spec computer as the files fill it up very quickly.

CMOS are relatively new and not all problems have been ironed out as far as I can see. 

IMO mono CCD and filters is the way to go, but many will have different prefences.

HTH

Carole 

[carastro]

Forgot to mention, it's not really possible to get a decent camera for both planets and Deep sky.  There are a few cheap cameras that claim to do both but I think this is only entry level.  Planetary cameras are cheap enough to buy separately.  

Carole 

[ollypenrice]

On 04/01/2019 at 15:36, carastro said:

 

OSC: As stated gives instant colour but is less sensitive than a mono camera.  Costs the same as a mono camera but you don't have to buy additional filters and filterwheel.  More straight forward to post process.

 

I don't agree with this at all, Carole, and I think Sara Wager has said the same. I spent a few years using OSC and mono versions of the same camera (Atik 4000) side by side and the Bayer Matrix of the chip is designed for use in terrestrial daylight, mostly reflected from objects, which is not at all the light we collect in astrophotography. The bias of colour collected by most OSC chips gives far more green than red or blue. (The matrix is RGGB) but nobody shoots twice as much green as red or blue in AP. It isn't quite as simple as that because the bandpasses of the colour filters bought for AP are not the same as those on an OSC matrix but I think that they are better suited to astronomy - for which they are designed. For whatever reason, I found processing OSC data rather difficult as compared with RGB from a mono camera. I'm firmly persuaded that mono-and-filter data are easier to process than RGB.

Olly

[carastro]

Quote

For whatever reason, I found processing OSC data rather difficult as compared with RGB from a mono camera. I'm firmly persuaded that mono-and-filter data are easier to process than RGB.

To be honest, I found that too.  But I did find DSLR colour processing quite easy in comparison, so thought perhaps it was just me being a dumbo and getting the Bayer matrix wrong when I bought a OSC CCD.  But overall it is less complex in that you don't have to combine lots of different coloured filters and get them registered and make all the stars line up.  

It's just that I took me a few months to learn how to combine mono data properly.

Carole