CCD Vs DSLR

[Mav359]

Hi Guys

Im big into the idea of astrophotography, im ordering a C9.25 in a couple of weeks and have been advised to mount a ED80 onto it, all good but which is better for astrophotography a CCD or DSLR.

I could spend £600 on a Canon or £1000's on a CCD, are they much more expensive because they are much better or because the technology is smaller?

I checked Peter Shah's website and he gets FANTASTIC results ussing a CCD, so is that the way to go?

[shaunster]

First off I would say if your big into astrophotography and its not for planets then ditch the idea of buying an SCT and put the money saved elsewhere..

[astroimpulse]

Unless you desire new; a Canon would cost much much less than £600

Remember...when using CCD you will need colour filters (if using mono) and filter wheel, preferably...so the cost will rocket.

I believe the quality and noise ratio on CCDs is superior to DSLR but many absolutely stunning images come from DSLR.

I've gone the Canon route as I can use it as a family cam too. When my bank balance recovers from my recent spending I will start dreaming of a CCD image rig...for sure.

[ollypenrice]

With DSLR you get a big chip at low cost. With a CCD you get better picures but on a smaller chip unless rich! A mono CCD is great for narrowband in light pollution and moonlight.

I would strongly urge you to think again about the C9.25. This long f length will require formidable guiding and there are lots of other issues. Have a think about the MN190 which is faster and optically more suited to imaging. SCTs are hard work on deep sky.

The ED80 is a great idea though.

Olly

[Mav359]

So are we talking a large DOB instead, i have 12 days to go before i can order and i want to get this right.

FLO have a 14" DOB, would that be a better way to go? seems a lot cheaper

[riklaunim]

Dobsonians can't be used for astrophotography in general.

[ollypenrice]

I really would not rush into this and don't take manufacturer's adverts as reliable.

If you want a recommendation for a deep sky imaging setup then I wlould run a thread on that issue.

To get good pitures you do not need huge aperture. Here are the key points:

What will fit on your picture is determined by the size of the chip and the focal length of your scope. Longer focal length scopes 'zoom in' which is not always good because many objects are large. I use a bought software to test what fits on what chip-scope but I gather there is a free one called CCD Calc. Look at this before you decide anything.

Longer focal lengths need far better mount and autoguiding accuracy. This is often the hardest thing to achieve. Longer than a metre is NOT the way to begin. To my mind over a metre is hard on budget mounts.

Fast focal ratios ( less than f7.5 ish) are vastly to be preferred because the exposure time rises as the square of the f ratio. Double the f ratio, quadruple the exposure time (and increase the problem of accurate guiding.) Aperture alone has nothing to do with this, exp times is controllled ONLY by f ratio.

What would I buy to start with? This is purely personal, okay, but I do a lot of imaging both for myself and with guests and I like things that work!

EQ6 mount, ED80 (Equinox) imaging scope, ST80 guidescope, One of the new autoguiders but I am not up on those, Atik mono CCD with Baader filters. Budget would decide between 314L and 8300. But I can see the case for a modified DSLR. They do need to be modified.

FLO, the forum sponsors, sell and advise well on all of the above. I have no connection with them, by the way, other than as a happy customer.

If you wanted to image and use your scope visually then the MN190 would be much better visually. It would not be so much 'better' as different for imaging.

It depends on your target, widefield or closer up. Many of us have a few scopes and lenses to cover a range of targets.

I mainly use refractors of 85 and 140mm. My stuff is here.

ollypenrice's Photos

[angusb1]

If you're really keen to take some astro photos you need to start by considering which mount to buy. It is of critical importance that you consider a mount at the same time as a telescope as the mount will only enable you to get photos without star trails or other tracking errors if it is not overloaded. Any mount you are considering will have a rating of how much weight it can carry, a good rule of thumb to follow is not to put more than 50% of this rating on it (excluding counterweights) if you want to use it for astrophotography. A motorised german equatorial mount with a guide port will probably be your best option.

[ollypenrice]

If you're really keen to take some astro photos you need to start by considering which mount to buy. It is of critical importance that you consider a mount at the same time as a telescope as the mount will only enable you to get photos without star trails or other tracking errors if it is not overloaded. Any mount you are considering will have a rating of how much weight it can carry, a good rule of thumb to follow is not to put more than 50% of this rating on it (excluding counterweights) if you want to use it for astrophotography. A motorised german equatorial mount with a guide port will probably be your best option.

Quite right, but focal length is the thing often overlooked. Only premium mounts (in terms of accuracy, not payload) can guide reliably at long focal lengths. In general mount manufacturers do not discuss this, preferring that you assume that their mount will do what it says on the tin. But if you are a regular imager you will know all too much about this issue!

Olly

[Neo_uk]

I have both a ccd and a dslr and to be honest the dslr is much much easier to use and can produce some very satisfying results.But i bought a ccd to take the next step and it is a very steep learning curve and a prolonged one at the moment with the weather being so rubbish.

hope this helps in some way ?.

chris......

[astrokat]

slr bud for starting out you will get more satisfaction when you get a colour image pop up on your camera

its easyer it takes less time to get good results

they are cheaper

you get the best fov for you money thins also makes tracking easyer

they are no were near as complex as ccd to use

i would go for a nice small apo refactor between 80 and 100mm and a eq6 skywatcher mount

thats just my personal view though

this is what i manage with a set up abit like above

[Grandad]

Hi All

I'm just starting in astrophotograhy using my Olympus E600 dslr on a Megrez 72mm. Picking up on one of the above comments; what are the main advantages gained from having the camera modified?

Also, how many times more sensative is a mono ccd such as an Atik 314L compared to a dslr at 1600iso , could I for example capture as much detail on the luminence channel in one minute with a ccd as against 5 minutes with an unmodded dslr? I am thinking long term I might be able to spend less time in the cold with a ccd (probably wishful thinking).

John:icon_scratch: