DSLR vs CCD for beginner on DSO

[jetstream]

When getting into imaging DSO,which camera is better to start with?I have a Stellarvue 90mm refractor(f7) that I can screw in a field flattener which is spaced for DSLR or I can use spacers to get the right distance for a CCD.Any ideas is much appreciated.

[Demonperformer]

Gerry

Looking at your equipment list, it looks like you only have an alt-az mount? If this is correct, that is going to be the major limitation on what you can achieve.

I'm no expert, but I would say go for the DSLR initially. It has a larger fov and will probably be more intuitive to use. You will be able to get some nice 'wider' shots (eg M81/82, or the galaxy fields in Com/Vir) which are probably more suited to the shorter exposure times you will be able to achieve. Remember the actual size of the object's image will be the same on a DSLR as a smaller CCD chip, which will only appear bigger because of the smaller fov.

HTH

[jetstream]

Gerry

Looking at your equipment list, it looks like you only have an alt-az mount? If this is correct, that is going to be the major limitation on what you can achieve.

I'm no expert, but I would say go for the DSLR initially. It has a larger fov and will probably be more intuitive to use. You will be able to get some nice 'wider' shots (eg M81/82, or the galaxy fields in Com/Vir) which are probably more suited to the shorter exposure times you will be able to achieve. Remember the actual size of the object's image will be the same on a DSLR as a smaller CCD chip, which will only appear bigger because of the smaller fov.

HTH

Thanks Demonperformer.I am planning on buying an GEM down the road-not sure which one.I have always wanted to try imaging and for now I'll try to learn as much as possible before gathering up the equipment and yesterday I ordered Making Every Photon Count.The challenge of imaging intrigues me,but I need to learn everything from the beginning.If DSLR is the way to go,I'll try to find a good used camera(Canon) and maybe do a filter mod to it(Astronomik),all the software compatibilty issues will most likely give me grief,as I am not yet very good with computers.Any ideas as to which DSLR cameras that would be easy to use would be fantastic.Image size,chip size,F ratio etc all confuse me at this point,I hope the book clarifies this stuff.My scope is a carbon fiber APO triplet & light at about 7 pounds bare,I figure with the flattener,camera etc will bring it up to about 11-12 pounds or so.

[kirkster501]

DSO astrophotography is a none starter without an equatorial mount or SCT/wedge combination. The latter is complex and time consuming to set up and take down unless left in a permanent observatory. GEM is the way to go.

[Demonperformer]

I have a Canon 1000D. The filter replacement made a vast difference to the results.

Using an altaz mount, I was able to regularly get exposures ("subs") of 20 seconds without too much trailing, but that really is more suited to the 'wider' shot approach. The CCD will give a lot more detail with longer subs (of 5-10 mins), but I always found short subs on the CCD to be far from impressive.

[ollypenrice]

You need to sort the EQ mount out first. This may not be the most appealing part of the kit but it is by far the most important. When you've read Steve's book you'll be convinced!

DS imaging is a costly thing and a DSLR gives you a big chip cheaply. However, I never feel it is a necesary stepping stone and I certainly don't think it's easier than CCD. I think it's harder! With DSLRs you are constantly having to work around things you don't want and make the camera do what you want it to do. CCD gear is designed to do what you want it to do. But CCD is far more expensive.

Olly

[micjyfynn111]

Hi. It looks like the we have the same query. I have managed to sort the

mount side of things out (EQ6). I have a 152mm f5 Bresser apo refractor

I was looking at the celestron 5mp solar system ccd camera. I actually

ordered one, should I be thankful it never arrived? Clear skies

[jetstream]

Hi. It looks like the we have the same query. I have managed to sort the

mount side of things out (EQ6). I have a 152mm f5 Bresser apo refractor

I was looking at the celestron 5mp solar system ccd camera. I actually

ordered one, should I be thankful it never arrived? Clear skies

Glad to here that you have figured out which mount to use,I am not there yet.Hopefully my scope at f7 will work well on DSO (without reducer),but I imagine there are more appropriate choices.I bought this one as a dual purpose telescope,it works great visually & is very forgiving on eyepieces.I have a Dob coming for visual,but I love what a refractor gives me too.It will probably boil down to specific set ups for specific object groups......before I buy anything else I'm gonna read my new book .I ordered directly from the author,so I have no idea how long to get over here.Those fast Televue refractors with the flat field design look pretty good...... & a CCD & a ......

[lensman57]

When getting into imaging DSO,which camera is better to start with?I have a Stellarvue 90mm refractor(f7) that I can screw in a field flattener which is spaced for DSLR or I can use spacers to get the right distance for a CCD.Any ideas is much appreciated.

Hi,

Take your time, save your money and buy the most sensitive and the largest ( chip ) cooled CCD camera that you can afford. You will pat yourself on the back in later years for not wasting money and time on an image aquisition camera that was never designed to do what we now ask them to do, a DSLR. If you already have one then fair enough use it, If you are going to buy one for both normal and astro imaging then fine but if you are going to buy one and have it modded for astro imaging then you are wasting time and money. Get a cooled CCD and smile from ear to ear. I have two astro modded DSLRs, Canons, and two CCDs, and old Atik 16IC mono and an Atik 428EX. The CCDs are a lot easier to use and get results from, are far more sensitive but they also have a narrower FOV due to sensor size, I find them much easier to use even for an impatient novice like myself. If you want to be convinced just have a look at the captures posted in this forum from both CCDs and DSLRs, the results speak for themselves.

Regards,

A.G

[Demonperformer]

I certainly would not dispute the fact that a dedicated CCD will produce better results in the right circumstances. However, I would maintain that with only an alt-az mount, the limitation is not going to be the camera, but the length of exposures. With alt-az mounts (I am just getting into using the EQ) I have always found the Canon to be far simpler [maybe Olly & AG can say exactly what they think makes using DSLRs harder?] and when you can pick up a second hand canon for a couple of hundred, it is a lot cheaper than getting a large chip CCD.

I think the question really is how sure are you that this is the way you want to go? If you are certain this is where your interest lies, then (as mentioned above) an EQ mount is the first priority. If, like me when I was starting, you really aren't sure if standing around without actually looking through the eyepiece will give you the same satisfaction, then a DSLR gives you a cheap way into trying it out. Just attach to the focusser at one end and the laptop at the other, set the ISO, # of exposures and exposure length and let it get on with it.

As for modding the DSLR, it does make it more sensitive at the red end, but I spent a long time initially with an unmodded one and only moved to a modded one when I knew I wanted to go down that route.

All that having been said, you won't find any "Olly-standard" photos by me on SGL, so maybe you should treat my comments with appropriate caution .

[ollypenrice]

I think what makes the DSLR hard are things like;

- No set point cooling so darks are likely to be all over the place wtih temperature changing during a night and even during an exposure. Hard to make a library because the outside temp you can measure isn't the chip temp which you can't. Bad darks do a lot of damage which will show up in post processing.

- Chip shakers stirring your dust bunnies around and making flats dodgy.

- High noise making background skies difficult to process.

- Shallow bit depth easily losing star colour.

- Compulsory one shot colour. Mono is more flexible and LRGB is usually easier to post process than OSC. I don't really know why but I think that it is, as do some other CCD imagers.

- Too small pixels not getting enough light at medium to long focal length and no possibility of binning because of the Bayer Matrix.

- Lots of controls to disable for astro use. I can't remember them all but when I've helped DSLR guests it seems like a lot!! (Pretty poor point, that one. Heh heh!!! But I'll leave it in the list...)

But you can't buy a medium format CCD for three hundred quid. Point taken and freely acknowledged.

I never have the courage (or rarely!) just to say 'ditch the DSLR phase' but honestly I do rather feel that way. A while back a guest said that he felt he'd wasted a lot of money under the influence of a very 'DSLR' magazine in the belief the these cameras had reached astronomical maturity. They haven't, of course, and the 60Da certainly hasn't! So he was full of regrets at not having got straight down to CCD.

On the other hand one of most respected imaging guests has just reverted to DSLR (at the F2.8 ratio of the Tak Epsilon, which does matter.) He'll be here fairly soon and I will need to sit down and speak to him severely!

lly

[jetstream]

Thanks Olley,I printed off "Choosing a CCD Camera" & found the info very enlightening-the pixel size vs resolution is interesting.If my seeing limits the resolution,I was thinking of using larger pixels-about 2"/pix,I checked out the Atik 314L+ & at 6.5um & my focal length it is in that ballpark....I think.Or should I go a camera with slightly smaller pixels in the hopes of some better seeing once in a while?I know the 314 isn't very big,but are its specs other than chip size good for me?

Thank You

[Uranium235]

It also depends on how much you are willing to invest, as the old saying goes - you get what you pay for. DSLRs are the thin end of what can be a very thick wedge!

Edit: Whatever CCD you choose (with the 314 as min spec), it will transform your imaging. Just make sure its mono and has setpoint cooling. The 314 can be gotten for about 700 quid S/H, that is a great camera (used to own two!) and it will see you for at least two or three seasons. After that, you may get a hankering for a bigger chip (similar to the affliction of apeture fever that observers often get!).

[swag72]

It seems to me that the DSLR first argument is almost seen as a Rite of Passage in AP. While there are of course advantages to it, especially if you want to use it for terrestrial photography, I don't believe that it makes sense in the long run. If you're not sure that you'll stick to AP, get a CCD with a 285 Sony chip second hand and then you can sell it easily and without losing much money if it's not for you.

CCD mono imaging is not as difficult as people initially think. The CCD's are made for the job and have good sensitivity and will give you many hours of noiseless imaging. A DSLR doesn't fit into either of these groups.

I'm not knocking DSLR's or those that image with them, but having done it myself, I wish I knew then what I knew now and I'd have avoided that area of AP. People do produce good DSLR images, but I think they take much more work in capture and processing than mono CCD images.

[ollypenrice]

This is great! Other people are making my controversial points for me!!

I don't think you need set point cooling with Sony chips. I'd say that the advantage of the set point Atik 314L was approximately zero over the old 16HR. Not so with the Kodak chips. Not by a long way.

I'd say that, in choosing a Sony chipped camera, chip size was ten times more important than resolution which, quite honestly, is over rated and whipped into a frenzy by people who spend more time reading the specs than taking pictures. Yes, getting a perfect sampling rate is nice but it doesn't change the world. I do lots of rubbish at a laughable 3.5 arcseconds per pixel.

http://ollypenrice.smugmug.com/Other/Best-of-Les-Granges/i-tP4vF2J/0/X3/VEIL%20COMPLEX%20HaO111RGBWEB-X3.jpg

http://ollypenrice.smugmug.com/Other/Best-of-Les-Granges/i-8Z28hkN/0/X3/HARGB%20P5SCNR%20sRGB%20SADR%20CILOUR-X3.jpg

Olly

[shirva]

Nice images olly..Davy

[StuartJPP]

It all depends on what you want to achieve and what your expectations are. I know some people who are happy to get anything that looks like a DSO.

So it is time for me to get shot down

A DSLR is the cheapest option for anyone wanting to start DSO imaging, from as little as £50 for a 10D and t-ring (I know someone who recently bought one for less, not that I would recommend one) or ~£200 for something quite capable.

A DSLR will give you colour for free, I am still new to AP and so technically a beginner and my personal thought is that beginners generally want to see colour images. Colour with CCDs costs even more. Narrowband can come later.

A DSLR can run stand-alone, so can work without being tethered to a PC. A wired timer controller can be purchased for £10. It can also be tethered to a PC if need be (Canon more so than Nikon).

A DSLR can also be used for daytime/terrestrial photography (until you take your screwdriver to it and remove the filter that is).

However, these are probably the only positives a DSLR has over a CCD (I may have missed some) but these can be very important for a beginner. There is no doubt that a dedicated CCD, even an entry level one, will outperform a DSLR. A DSLR may be outgrown very quickly.

There is also the question of what type of beginner as in a total beginner to astronomy (like I was), or a seasoned visual astronomer wanting to take up AP. Because if you are new to it all, you have to be sure and have decided that you are happy to stand out in the cold, hating the moon and waiting hours for the clouds to disappear. Then and only then would I recommend spending serious money on kit. The OP obviously isn't new to it all but it is still important for other "beginners".

When it comes to which is easier to learn? I am not sure, especially when the person may not be familiar with either. The CCD will most probably be easier since it is specific to the job. Personally I don't think this is really an issue, processing the end result is way more complicated than learning how a camera operates.

The problem with asking advice of people is that for every person you ask, you will get another, sometimes vastly different, point of view.

[jetstream]

" you have to be sure and have decided that you are happy to stand out in the cold, hating the moon and waiting hours for the clouds to disappear. Then and only then would I recommend spending serious money on kit. "

This sounds like me Lake trout fishing!! Up at 3am,driving 100km,unloading snowmachines,drilling holes in the ice.....going thru the ice & loving it!LOL!

Seriously though,I spend a lot of time outside as it is and I would love to try astrophotography some day.I really appreciate comments from both sides of the fence,it is so good to hear peoples experiences.In my case I may buy a camera dedicated to AP,but I need my new book first of all!So i have a plan:figure out which mount to buy,use the mount to become so familiar with it,that using it is second nature,pick out and purchase an appropriate camera,& then try to figure out how to use all the software-actually I may try to figure out the software first some how.Thats my tentative plan here anyway.

[lensman57]

This sounds like me Lake trout fishing!! Up at 3am,driving 100km,unloading snowmachines,drilling holes in the ice.....going thru the ice & loving it!LOL!

Seriously though,I spend a lot of time outside as it is and I would love to try astrophotography some day.I really appreciate comments from both sides of the fence,it is so good to hear peoples experiences.In my case I may buy a camera dedicated to AP,but I need my new book first of all!So i have a plan:figure out which mount to buy,use the mount to become so familiar with it,that using it is second nature,pick out and purchase an appropriate camera,& then try to figure out how to use all the software-actually I may try to figure out the software first some how.Thats my tentative plan here anyway.

Hi,

I came home about an hour a go and rushed snd set the mount the scope to do a quick run on M27, i am using sW 80ED @ f6.4 and my atik 428EX OSC, the camera has an Idas LPV2 and a Baader UV/IR cut filter mounted the nose. using the Artemis capture M27 was clearly visible with some distinct colour usinloop of justg a focus- alignment loop of just 2 seconds and this is an OSC camera, a mono camera will be quite a bit more sensitive. had I opted to use my astro modded canon I would have had to opt for an exposure of at lleast 15~20 seconds to see the shape of the M27 and this is one bright nebula , for the real faint stuff I have used up to 3 minutes exposure to get the framing right and this clearly shows the difference in sensitivity between the two, that is why I find it easier to use a CCD rather than a DSLR.

Regards,

A.G

[Demonperformer]

Gerry

I think that is a good plan. Most significantly for this discussion is starting with the mount improvement. Once you have a decent EQ mount, you will be able to take much longer subs, which in turn obviates a lot of my original comments.

For years people on here have been telling me to invest in an EQ6, but I always put it off because I didn't have the funds. The irony is that during that time I have spent more than the cost of the mount in getting extras which I will only be able to use properly now I have one! Also some early experiences with 'cheap' EQ mounts, which I found nigh on impossible to use - in comparison the EQ6 is a dream [not that I haven't had my issues with it!].

[Demonperformer]

I think what makes the DSLR hard are things like;

- No set point cooling so darks are likely to be all over the place wtih temperature changing during a night and even during an exposure. Hard to make a library because the outside temp you can measure isn't the chip temp which you can't. Bad darks do a lot of damage which will show up in post processing.

- Chip shakers stirring your dust bunnies around and making flats dodgy.

- High noise making background skies difficult to process.

- Shallow bit depth easily losing star colour.

- Compulsory one shot colour. Mono is more flexible and LRGB is usually easier to post process than OSC. I don't really know why but I think that it is, as do some other CCD imagers.

- Too small pixels not getting enough light at medium to long focal length and no possibility of binning because of the Bayer Matrix.

- Lots of controls to disable for astro use. I can't remember them all but when I've helped DSLR guests it seems like a lot!! (Pretty poor point, that one. Heh heh!!! But I'll leave it in the list...)

lly

I don't want to get too far off topic, but in the context of using an alt-az mount:

Darks: when limited to a 20sec exposure-length, with maybe a 10sec gap between, I have tended to do 10 darks before I start the lights with another ten after. Total time 10 minutes to get 20 darks. [i fully acknowledge that when taking 20 minute subs, this would not be an option]

Flats: not sure what chip shakers are. Also true that I have never really got into flats. Maybe this is me or maybe down to limited exposure length again, but I have tended to spend far shorter total times on images. 2 hours of data with one sub every 30sec is 240 exposures. As such I have tended to try to get several objects in a session and without an EL panel, this has meant I have only considered doing flats at the end of the night when the sky is getting brighter.

High noise level: definitely.

12-bit vs 16-bit: again true. But is this such a big problem when you are limited to such short exposures?

LRGB vs OSC: Flexibility - I would not argue with. But you have the additional requirement to take four lots of flats. As regards processing, aren't you having to process four sets of data and then having to go through the process of combining them, compared to simply processing one set of data?

Pixel size: the canon has a pixel size of 5.8u and my H9 has a pixel size of 6.45u, giving about 25% more area. Agree that binning is not an option, but would you be binning an OSC CCD?

Controls to disable: I'm not sure what they are either. Maybe I disabled them when I first started and they stayed that way? Or maybe I have just failed to disable what I ought to disable?

I need a mains power supply to run the H9, whereas the canon I could (if I had transport) take out to a dark site and use there.

Writing this response, I wonder if I maybe had too low expectations of what I could achieve when I started out. My first 20sec sub of M81/82, with all the orange background from the streetlights thrown in, blew me away. And I have regularly used my canon/laptop screen simply as an additional eyepiece. Maybe I have just been happy to be like a tourist who takes 'snaps' of 'a mountain' 'another mountain' 'even more mountains' [for 'mountain' read 'galaxy'], rather than the professional photographer who takes well thought-out "professional" photographs. But if in taking these 'snaps' my appetite and expectations have grown I would consider the experience worth while.

But then, maybe an alt-az mount is the mount equivalent of an instamatic.

[leelee970]

^{I think the most important thing is to have FUN.}

^{I was blown away with my first DSO using just a modded SPC900 webcam.}

^{It wasn’t going to win any competitions but I was just pleased I’d imaged something that resembled those in the glossy mags.}

^{Everyone here has valid points and I dare say some are more suited to your situation.}

^{If you have the money, buy the best (but there is always some bit of kit that is better).}

^{At the end of the day you will only get good results with practise and dedication.}

[nmoushon]

^{I think the most important thing is to have FUN.}

This truely is the most important thing! Some people have ventured into AP and found out that its not for them and went back to purely visual, which is fine of course. Just make sure you do what you like. When I first started I fell hook, line and sinker and rod and fisherman into AP.

I started similarly to you. Except I started with my dslr and stock lens and then went to the mount and then the telescope. I agree that you should read the book completely through..maybe even twice. It does a good job of explaining better than a post on here can. Tis why everyone here suggests it. I bought a similar book here in the USA and it really helped my out. It will explain all the basics about AP and the equipment used and then some. Will really help you with your final decision.

I've used my dslr for AP for almost 2 years now a love it. I haven't used a CCD so can't comment much on that BUT I don't think using a dslr is as hard/pain as some posts have made it out to be. Yes theres a check list of things you need to change in the settings which you don't have to bother with with a CCD but that takes no more than 5min to make the changes and then you don't have to mess with them ever again. Unless you switch the setting back for daytime use.

The greatest advatage dslr has over CCD is that you don't need to have a laptop outside with you. For me that was a HUGE advantage when starting out. I only had my laptop outside with me when I was doing polar aligning and then took it inside. Once I had everything setup and target in the FOV I left it to take pictures for me while I stayed inside nice and warm.

The second biggest advantage is the price. Second hand let you afford a decent camera that really will show you what you want to see. They won't give you the quality image a CCD camera gives but I think its a safe way to "test the waters" so to say. You have to keep in mind that its not just the camera price you have to consider. With a CCD you also have to buy the filter wheel and at least 3 filters if not 4. Which, depending on what you buy, can cost close to the camera itself.

But once you get into AP you will eventually be wanting a CCD...its only a matter of time...and money. You will eventually want to get into guiding as well and this will require a computer so at that point the only reason you shouldn't be switching over to CCD is because of money. Thats the point I'm at currently. Just got guiding going this spring and now saving up for a CCD camera as my next big purchase.

Good luck with everything.

[ollypenrice]

Well for me groping around underneath the tiny screen of a DSLR would be the ultimate nightmare! What if you are on the zenith? And then you are handling the buttons physically and so breaking golden rule number one, Don't Touch the Telescope!

I'm the last person on earth to use a PC when any other alternative whatever exists, but for controlling a DS camera and taking a DS image, no such alternative does exist. I even heard it suggested that you could take out the DSLR to check screen and focus and then put it back again. Barking mad! Flats? Focus? Nope, use a computer for imaging.

Olly

[StuartJPP]

Well for me groping around underneath the tiny screen of a DSLR would be the ultimate nightmare!

Most true Olly, but before we can run we have to crawl (under the LCD)

I really struggle to frame images myself, especially at zenith, but there are loads of objects that are not at zenith. Zenith would of course be the best option, but not the only option. I also struggle to frame images, because my GOTO uses the Mk1 eyeball and a star chart.

Here's an analogy, I like taking photos of birds, which is the reason I have got a large lens and a mid range DSLR and a large tripod and gimbal head and a bean bag and a monopod and.... If someone asks what is needed to take photos of birds, I can't quite say to them that you need the above. Sure it would be great, but perhaps the person only wants to take the occasional image, without having to leave the wife behind because there is no room in the car for her and the kit, and maybe next week give up the whole thing because it wasn't quite what they expected (I actually know someone who did this!). There are many options for taking photos of birds, most notably bridge cameras (super-zooms). Are they any good, not particularly compared to a DSLR, but it may be good enough for a lot of people, and sometimes some very good images can be produced. Are they going to be Sara, Olly et al. beating images...I doubt it.

Don't get me wrong, once you have made up your mind that you want to pursue something further, then go for it, don't upgrade every other week, rather save your money and buy once you know what/need to get. And if you have already made up your mind that you do want to take it seriously before buying any kit, get the right stuff the first time.

I'll say it again just in case people read this as me being anti-CCD, there is no doubt that a dedicated CCD is much better than a DSLR, in so many ways, but sometimes something simple may be all that is required.

I even heard it suggested that you could take out the DSLR to check screen and focus and then put it back again. Barking mad!

Couldn't agree more.