40D or 50D? Or even something else?

[ollypenrice]

If it wasn't for local light pollution and my need for an upgraded mount I'm sure I could do that with a DSLR

Definitely a good CCD is better than DSLR. But good CCDs just don't go at lower price points, hence the popularity of using DSLRs for those who don't want to blow megabucks.

There is no doubt that for a big chip at a low price you can't beat a DSLR. Nor is there any doubt (in my mind, humble thing that it is!) that a CCD will kick anything else into the latter part of next month when it comes to quality per square mm of chip. Save money on the optics with a short FL scope and put a small chip CCD in it. Look at Mike Duggan's galaxies. It's a no brainer.

Olly

[ollypenrice]

If it wasn't for local light pollution and my need for an upgraded mount I'm sure I could do that with a DSLR

Definitely a good CCD is better than DSLR. But good CCDs just don't go at lower price points, hence the popularity of using DSLRs for those who don't want to blow megabucks.

Indeed but the OP said,

40D or 50D? Or even something else?

... and I'm saying, 'something else.' Smaller chip, ten times better, with smaller, shorter FL, cheaper scope and away you go.

Olly

[GlassWalker]

Olly, the variables are many and complex. Personally, I'm not sold on the small sensor CCDs as they're not convincing enough for me to seriously consider replacing the DSLR for deep sky stuff. Having said that, I am thinking of getting one purely for solar imaging and future guidecam use.

To Zendrix, there are always lots of options which are never easy. My experience has been significantly with DSLRs so I can't give practical advice beyond that.

[RikM]

What about Imaging SOurce Cameras? They are in the category of the CCD and are lower priced... any good investments there?!

Back on topic <ahem> the imaging source cameras are 'fast frame rate' cameras. They do have CCD chips, but are meant for taking short exposures rather than long. They take many hundreds and even thousands of frames (as a video file). This is for planetary imaging rather than deep sky but actually your scope is rather better suited to this use than deep sky anyway.

So, yes...they are worth considering...but not for galaxies and nebulae.

[ollypenrice]

Olly, the variables are many and complex. Personally, I'm not sold on the small sensor CCDs as they're not convincing enough for me to seriously consider replacing the DSLR for deep sky stuff. Having said that, I am thinking of getting one purely for solar imaging and future guidecam use.

Are the variables really that complex?

DSLR, big chip, low price, high noise, shallow well depth, nearly useless in narrowband, no good in moonlight, no set point so big issues with darks.

CCD, small chip, higher price, low noise, deep well depth., brilliant in narrowband, useful in moonlight, set point cooling, simple darks library.

Olly

[GlassWalker]

If you really want some more reasons why small CCDs are no slam dunk: Narrowband on a DSLR certainly is a bit more challenging, since in the worst case you are only effectively using 1/4 of the sensor, but that also affects colour CCDs equally. It would still be comparable to a small mono CCD in light collecting area. I think a lot of people do use them for colour anyway. Well depth obviously depends on the specific sensor, but could be offset by having more wells collecting less each typically. Small CCD outputs are very low resolution unless the user spends time doing a mosaic to build up the spatial resolution. Which ties in with field of view considerations. While I'm still early on the learning curve on the processing side, so far I've had reasonable results without using darks at all. Maybe that will change if I wasn't light pollution limited though...

I think if we're to go any further on this we probably should be in another thread...

[ollypenrice]

[quote name=

I think if we're to go any further on this we probably should be in another thread...

Yes, perhaps so, but the OP did raise the possibility of 'something else.' Of general interest in choosing any camera, DSLR or CCD, is the business of pixel size. In daytime imaging small pixels equate to higher final resolution. In astrophotography they won't do this if they are trying to resolve below the limit of the seeing, which can easily be the case.

Furthermore, if they don't get the signal in the first place they won't have anything to resolve! Larger pixels tend to be more sensitive so one thing not to bring into consideration is the pixel size of different DSLRs.

Oh, I forgot a 'plus' for any one shot colour system; you only need one flat.

Olly