Imaging Source CCD camera? DFK 21AU04.AS

[Matty P]

I am looking for a CCD camera for imaging the Planets and maybe even the faint DSOs. Will the DFK 21AU04.AS allow me to do that?

I have found the Imaging Source DFK 21AU04.AS. The camera is a USB2.0 allowing it to capture up to 60fps non-compressed. With a 30-second video, you have 1800 frames! :eyepop:

http://www.astronomycameras.com/en/products/usb-cameras/colorir/dfk21au04as/ (http://www.astronomycameras.com/en/products/usb-cameras/colorir/dfk21au04as/)

Color USB camera with IR cut filter
1/4" CCD, progressive scan
Max. 60 fps
Max exposure time 60 min
Resolution 640 x 480

The camera has a max exposure time of 60min, does that allow it to take long exposures of DSOs?

I am wondering what exactly comes in the box with the camera? Does it include all the cables I need to plug into my USB2.0 port? Can I simply plug it into the PC or do I need other hardware also?

Do you need any additional accessories with it?

If anyone has had any experience with this camera, can please give me your honest opinion about the camera. Thanks

Best Regards
Matt

[turbo_pascale]

Lots of people on here have the various models of these cameras, although the USB2.0 ones are brand new - most here have firewire models.

Planets - definitely.
Guide cam - great.
DSO - hmmmm possible, but they are not going to be awesome.

For a chuckle, I took a 5 second exposure of the trapezium stars in M42 through my 10" scope at F/10. You can see there is some of the nebulosity there. Mind you my camera is a colour one, not the mono, and is 1024x768 and only 30fps (this is scaled down for the web).

In terms of the firewire cameras (can't talk USB ones), you need to supply them power, either by a full 6-pin firewire cable (ie most laptops only have the 4 pin connector which doesn't include power), or by plugging them in to a powered firewire hub.

Mine did not come with the power cable (or power supply), nor did it come with the C-mount->1.25" adapter, which I had to purchase separately. On some of their ads, they do supply the adapter, but you'll have to check with various dealers to see what they offer, as it appears to be changing over time.

Depending on what you're shooting at, you might want to consider getting an IR/UV cut filter. There are people far more expert at planetary imaging here (iceman!) who can give you all the reasons why this might be important.


Turbo

[iceman]

The DBK is the better of the colour models of the D*K cameras, rather than the DFK. The USB is great for not needed etc powered cables, if you use 240v at home.

Don't get it for DSO's though. While it can do it, it's not designed specifically for it. It will do ok, but it's real strength is lunar and planetary.

You'll need a 1.25" adapter (as with the ToUcam) but with the C/CS thread. Mogg Adapters sell these. I got mine for US$25.
It comes with the software you need for capture (IC Capture) and for imaging processing you'll use Registax, same as with the ToUcam.

[citivolus]

Also remember that this is an 8 bit camera, so any stretching of individual frames will be very limited.

Keep in mind the sensor size. On your 200mm SCT, most DSOs will be truly huge. M27 will fill the frame. Guiding would be a tad on the challenging side.

[Matty P]

Hi Turbo & Iceman,

On the website there is an image taken of the Dumbbell Nebula (M27) and it looks pretty good to me. I know the D*K camera is intended for Lunar & Planetary use but if it is possible of taking half decent images of DSOs. I'm sold! I have a few questions

What is the difference between the DFK, DBK and DMK?

How does the Toucam compare to the D*K cameras? Would it be better with a IR/UV cut filter or without one?

I want to start out with the best possible camera for a reasonable price? Do you think it is worth it?

Thanks for the help

Best Regards
Matt

[iceman]

There isn't a single camera that does both (DSO and planets) very well. There's always a trade-off. Similarly, the types of scopes are also best specialised in a particular application.

A C8 is probably ok for planets and will do a reasonable job, but for deep-space, the long focal length will make it very challenging, and the small pixel size will make it even harder.

You probably need to decide what you want to do - lunar/planetary or DSO's. And then pick the scope and the camera to do it well.

[Matty P]

I think my best option is to start out with Lunar & Planetary imaging to get my feet wet. I have decided to start out with the SPC900nc.

How does the D*K compare to the Toucam?

Best Regards
Matt

[Lee]

The DMK makes a great guide camera....

[Stephen65]

I use a DMK21 for lunar imaging. It's superior for that use to the Toucam/SPC900 because you can run it at higher fps and being a B&W camera it has a higher effective resolution than a colour cam like the SPC of the same pixel dimensions. Apparently it also has less noise.

All that said, the SPC900 is much cheaper and a very good introduction to planetary webcamming, since it is colour you can use it on the planets without filters. It,s what I used till I switched to the DMK.

[Matty P]

If I decided that I want to start out with one of The Imaging Source cameras instead of the Toucam. I would like to know which D*K is the best for a beginner. Ideally I would like to get into imaging with the best quality camera possible. With the D*K series I'd preferably like to get the DFK 21AU04.AS (USB version). Which would be the best to start out with?

DMK
DFK
DBK

I'm still deciding between the Toucam and the Imaging Source cameras. I know both would be great camera and produce amazing images.

My question is now, which one to get? :shrug: :sadeyes:

Best regards
Matt

[iceman]

The DMK is the best of the Imaging Source cameras and will deliver the best quality images, but it's not a beginners camera. It's monochrome, not colour. So you need coloured filters and a filter wheel. The cost goes up. The time to capture goes up. The time to process goes up. I wouldn't recommend it for you at this stage.

If you want to get a DBK or DFK, get the DBK. It's more suited to astronomical imaging.

Planetary imaging has quite a learning curve so don't expect to get the best results straight away just because you get the best camera. There's a lot of factors to consider and a lot of work in capturing and processing.

I'd still recommend the ToUcam to start with.

[Dennis]

Hi Matt

Do not consider the DFK (colour) – it has a factory fitted (non-removable?) IR filter designed more for general terrestrial use; it is not optimised for astronomy. So, that leaves you with:

DMK – mono, no filter fitted as standard, or,
DBK – colour, no filter fitted as standard.

For both the DMK and DBK you will need to purchase an astronomical UV/IR block filter, such as the Baader one.

I have a DMK (mono) which is great for high resolution imaging of the Moon. It is more sensitive and less noisy that the DBK (colour) if you want to use it as an auto guider.

I also have a DBK (colour) for brighter double stars. When I have compared the DBK with the DMK, I find the DBK noisier (I have to pump up the Gain more) for fainter multiple stars, such as those in the Trapezium in Orion, whereas the DMK requires less Gain and therefore produces nicer images – it allows you to go “deeper”.

I suspect it will be almost impossible to make a judgement based upon just reading text in these posts, so purchasing either camera may be a risk, possibly leading to some disappointment unless you have previously tried imaging with a webcam?

I have used the DMK and DBK on the same objects in the same session and the differences become very clear when seen in this manner. I would recommend you try to get some practical experience if someone lives nearby, as that will reduce the uncertainty in your decision – it is not an easy one!

Cheers

Dennis

[Matty P]

What is the difference between the DBK and DFK?

Best regards
Matt

[Matty P]

How is the DBK for planetary use?

I could start out with the monochrome version and only take B & W images. Then when I feel I am ready to advance, I can buy a filter wheel to take colour images.

Best regards
Matt

[rumples riot]

Just a couple of side line issues.

1. Getting 60 fps depends on whether you use a small image scale with a small barlow or using a much larger aperture and a larger aperture. Just like a terrestrial camera you need to expose the frames correctly to prevent either over exposure or in this case under exposure. You won't be able to expose your frames very well and have large image scale with a 200mm telescope. There is just not enough light to make that happen. You will be able to use a 2X or 3x barlow and image at around 6000-7000mm. Jupiter for instance will look about 45mm on a frame. In that case you might be able to image at 30fps. I have a C14 and can only image at 45fps max at 14000mm. Jupiter is the size of an large orange in that case, so you can see 60fps is really only reserved for really bright objects and having a really large scope.

2. Yes, you have a valid point you could buy a mono and learn how to use the camera and some basic processing. It will mean you will not have to spend more money if you really get into planetary imaging. My vote, yes.

3. If you choose not to get the Mono, rather than get a Toucam (900nc) get the DBK; it comes without the IR cut filter in front of the chip. It is better for astro imaging. The DBK is a better performer too. So this is recommended if you want to go with a simple colour camera. It cost more than the 900nc, but gives better images once you practice focus and the controls.

So something to think about, but I reckon the DMK (can be a guide camera and planetary imager but in colour) or the DBK and that will get you better quality images in colour than the Toucam.

[turbo_pascale]

DBK = Colour - no IR filter built in
DFK = Colour - non-removable filter

Personally, get the DBK, as you can add the filter later, when, and if you need it. Sometimes not having it is a bonus, other times, having it is good. Best of both worlds, but it will cost you more to get the filter. I always opt for the flexibility option.


I'm lazy, and for what it is, I could not be bothered with the filters and stuff (I already have that with my SBIG camera). For me the DBK was about more "instant" gratification with bigger resolution than a 640x480 webcam.

My results with the DBK31 (slightly bigger chip at 1024x768) are here:
Jupiter: http://www.iceinspace.com.au/forum/showthread.php?t=24366
Moon: http://www.iceinspace.com.au/forum/showthread.php?t=24373

Turbo

[Matty P]

Turbo they are some great images of Jupiter and the Moon. I think the DBK is the best option for a total beginner.

What exactly comes with the camera? Are the cables and mount included?

What is RAW format imaging? Does a camera with a bigger chip produce better quality images?

Thanks for the help :thumbsup:
Matt

[turbo_pascale]

You need to talk to a dealer about what comes in the packages now. There are a few extra bits you need to get.

Bigger Chip = Better Quality????? NO - just higher resolution. There's a lot to take in to consideration with this kind of thing. Hence, my next point.

Matt, to be honest, these are not beginner cameras (for the price). They will be good longer term, but you're spending a lot for a "total beginner".
I would recommend you hit eBay or some of the astro trader sites, and see if you can get yourself a Meade LPI or Celestron NexImage - Brand new they are selling for $150, so you should do better than that. The advantage of these over a pure webcam is that you don't have to get any mods to them, all the bits come with them and the software is specifically geared to astro work. They can be had quite cheap second hand. My first planetary image came from the LPI, and it was a great way to learn.

Don't get me wrong; I'm the kind of guy who jumps in at the deep end. My first scope is what I have right now (not even a cheap tasco beforehand). Not what many would consider the sane way to jump in to astronomy when you don't really know if you'll even be able to work out what all the gear is used for.

Before you dive in the deep end, dip your toe!

Turbo

[Matty P]

I've searched the web and the cheapest price I have found for the Celestron Neximage is $230 not including postage. I'm not quite sure about the Meade LPI though. The Imaging source cameras are only an extra $100 and overall it is probably much better. Is the D*K much different compared to the Neximagers and Toucams?

Best Regards
Matt

[Lee]

They are more expensive than the toucams - but you will see why - look at the quality of planetary images people do, and look at the build quality of the camera. Beats any other webcam I've seen.
I did the sums - by the time I'd bought a Toucam, had it modified, picked up a nosepiece for it - I was at least 60% of the DMK price anyway.
Go for it Matt.....

[Matty P]

I've definately made my decision that the D*K cameras (USB version) is the best way to go. Now which one? :)

The DMK is a monochrome camera, It produces the best quality images but is not suited for a beginner. With the DMK I could start out with B & W then eventually step up to colour using filters.

The DBK is a colour camera with no IR cut filter, Compared to the DMK I don't think it produces the same quality images but is more suited to a beginner.

Also, which resolution 640x480 or 1024x768? Is the C/CS Mount threaded if I wanted to add filters? How is the camera software?

Sorry about asking so many questions :P
Matt

[Matty P]

Also, Does the USB version of the camera need and external power source or does the USB cable suply the camera with the power? :shrug:

[Matty P]

Where is the best place to purchase the D*K cameras? Online or at a store?

[rumples riot]

Matt, 640x 480 affords nice fast imaging, but the larger format is good if you get into imaging the moon. The larger format is slower in frame rate, so it is a choice you will have to make. You will more than likely be happy with the 640 x 480 format.

The C mount is threaded for filter use and the camera software is very nice to use.


You will not need an external power source with the USB version. Although you might want to check that you have USB2 for the fps.

Bintel supply the camera at their site. You could also try Matthew Lovell at Telescopes and Astronomy. I also believe that York Optical now have them too as seen by the Ad on this site.

[vash]

In the next year I'm most likely to get a new planetary/guide camera and am throwing around different Ideas.

My thought it that you can get the B/W (640x480) DMK camera plus filter wheel for $814 (from Bintel site) then just buy which ever filters you'll need, I don't know much about which filters are best.

The next DMK camera up is at $939 (1024 x 768), so that gives you $125 to spend on filters.

But later on you can upgrade the camera and still keep the filter wheel and filters so this is most likely what I'll be doing.

[[1ponders]]

If you are prepared to pay the bickies then go for Astronomik filters.

Another supplier of the D*K cameras is Steve from Myastroshop.

[IanL]

I have just asked mrs claus (Her in doors) for a new camera:prey: and i have just read this thread. :juggle: so many to choose from.

I think i have read this thread about 8 times and every 4 replies i think right thats the one then i see something else.

Gees it not easy.
She said YES:eyepop:

Ian

[Matty P]

I second that! :confuse3:

What type of camera were you thinking of getting?

Also, can't I just buy the camera directly from the Imaging Source website? It is much cheaper than everywhere else? :shrug:

Best regards
Matt

[citivolus]

Telescopes-astronomy.com.au sold me mine (DMK 21AF04) for $395 AU + $10 shipping. Not bad at all. You'll still need a C adapter at that price, though, as you would if you purchased directly.

Eric

[Matty P]

Hi Eric,

The stats for the DBK 21AU04.AS (USB 2.0)

Color USB camera without IR cut filter
1/4" CCD, progressive scan
Resolution 640 x 480
Max. 60 fps
Max exposure time 60 min
C/CS Mount
Software included (http://www.astronomycameras.com/en/products/software/)

Does that mean the C mount is included with the camera? :shrug:

Best regards
Matt

[[1ponders]]

No unfortunately, it just means that the thread on the face of the camera ia a C/CS mount size thread. C and CS are identical thread and pitch but one is longer in depth. The camera comes with a threaded insert that can be removed or added to use either a C threaded lens or a CS threaded lens

[ballaratdragons]

Originally you mentioned that you also want to image faint DSO's as well as planets.

Faint DSO's is a specialised area that D*K's won't do, nor will the Toucam unless you get the Modified Version.

For DSO's I'd recommend a DSLR (unless you have a few spare grand for a SBIG etc). For planetary/lunar imaging Id recommend the Toucam for cost and ease of use.

After 6 months to a year you will know more about how to use these cameras and which direction to take. Then you can step up to a more serious camera.

Cameras will also need to be matched to your telescope. Then for DSO's you will also need a guidescope and a guiding camera.

. . . . and on it goes.

Imaging questions are not easily answered, but it's always good to start at the bottom and discover what you want in a camera.

For cost and ease, I'd recommend the SPC900NC or Toucam 840k Pro II.
Then go from there.

[matt]

Well...based on a few of the images I've seen, DMK's are capable of producing long-exposure DSO images. Not 'out of this world' DSO images, but then neither are modded ToUcam DSO images. IMHO.

BTW...That's not intended as a put-down of the modded ToUcam. It's just an opinion. I'm not looking to get into a debate over the relative merits of the modded ToUcam or the images it's capable of producing.

I was very happy imaging planets with a ToUcam for many months and I think they are a great little cam for what they are.

It all depends on what you are looking to achieve, Matt.:)

Have a look around, see the sort of images different folk are producing. Decide what images you find pleasing and take note of what gear they are using to produce those images.

That will give you a basic guide to what's achievable with what cameras/scopes etc.

Of course, it then comes down to individual capability to getting the best results out of the equipment.

[Matty P]

What do you mean? :shrug:



What I meant was is there a camera that can successfully take both Planetary and DSO images not including the quality of the image. If you know what I mean! :D

Also concerning the issue about the D*K cameras not suiting a beginner. Deciding on what is my best option for a CCD camera is very very very challenging! After doing my Math, I found that the 900nc with all accessories comes pretty close to the D*K 21 camera. So getting the D*K is not such a big difference. I realise what you are saying that the 900nc is the best for a beginner for the ease of use and low cost but if you're like me, you would know what I am trying to say!:thumbsup:

Don't worry if it doesn't make sense to you, it's just me talking to myself. :rofl:

Regards
Matt

[[1ponders]]

I see you have a Celestron 8SE. Do you have a wedge to go with that to mount it in equatorial mode? Without being mounted in equatorial mode you are limited in the DSO imagery you can undertake. You will get field rotation after a very short period of time. Meade DSIs get around it by using drizzle technology, but I'm not sure if that is available for other cameras. Also do you have an off axis guider for guiding your DSO imager or are you thinking of getting a guidescope? That option might be a bit much for the single arm 8SE.

[matt]

Yeah. I think I understand what you mean.;)

I think the advice you've already received in this thread is very good and the guys here know their stuff.

If you go the path of the colour Imaging Source camera, I'm sure you'll pick it all up very quickly.

You can always post your questions here if you get stuck.

The traditional path tends to be simple webcam (ToUcam/NexImage) before 'graduating' to something more involved/expensive.

But follow your own path.

[Matty P]

No, I don't have a wede just yet. I really want to start out imaging planets before I proceed to the more challenging DSO's. If I was going to get a wedge for my 8SE, I'd rather just buy a new EQ mount to put my OTA on.

Now going back to the DBK. How is the DBK with the Moon?

Matt

[Matty P]

I would like to add, Thankyou for the advice all you guys have given and it has made this transition that much easier.

Thanks! :thumbsup::D

[matt]

Who knows?:shrug:

Why would you buy a colour camera to shoot what is largely a mono target? If the moon's a big thing for you, the DMK is your 'toy'.

The (mono) DMK performs beautifully on this target, but as you know you'll need filters/filter wheel to move on to colour images of the planets.

I've not seen any moon images with a DBK ...yet.

As indicated in prior posts, there really is no one size fits all imaging camera. Decide what your imaging 'goal' is ... and choose a camera from there.

[[1ponders]]

I think Dennis might have done some moonage with his DBK.

[matt]

Hmmm.

Care to chime in here, Big D?

[[1ponders]]

Just checked. I think the only ones Dennis has taken are with the DMK. Sorry

[Matty P]

Calling anyone with a DBK!

What are the advantages and disadvantages on taking images of the Moon with a colour camera. (DBK)

[iceman]

The same disadvantages as taking colour images of planets with a one-shot colour camera.
Reduced resolution.

[matt]

And there you have it:D

[IanL]

Matty in reply to your question.
I think I am going to go for the mono and filter wheel.

PS
Thanks to all who posted on this thread. Your experience/knowledge in choosing a camera has helped and others with what seems to me could possibly be a mine field.

Cheers
Ian

[Dennis]

Hi Guys

Thanks for the plug! Well now, let me see, it seems quite a while since I did some of this imaging stuff. If I am going to image the moon, I will plug in the DMK. I have noticed that it produces better images than the DBK. What do I mean by better?

Well, the DMK live images look cleaner, show less noise, allow for higher frame rates and have more in reserve if I need to pump the image for faint objects, or those with a high brightness range.

I have never experimented with the DBK as a mono camera, I have always used it as a colour camera and in this mode, lunar images are dimmer and noisier at the same settings, so I have to increase the exposure time, lower the fps and pump the gain.

I use the DBK mainly on colourful multiple stars where I can pump up the Gain as we are dealing with point sources. However, if I want to split close doubles that are faint, the DMK is superior in 2 ways;

It goes deeper so I can image fainter doubles.
The dynamic range seems superior; that is, where the brightness difference of the components are large, such as mag 3 and mag 10, I can play with the settings and capture both using the DMK, whereas the DBK hits the wall at around 7 or 8 mag where noise and slow frame rates become dominant.

However, I will reiterate – I have always used the DBK in colour mode and not used it in B&W mode.

Hope that helps!

Dennis

[Matty P]

Hi again,

Just for the fun of it,

Can you please place your vote on which Imaging Source Camera I should get.

The DMK or the DBK? keeping in mind that I am a total beginner.

1 vote for the DBK

[citivolus]

Ultimately the DBK will be more "plug and play" in the short term. You can always sell it down the road...

[iceman]

You don't buy a DBK just to image the Moon. You buy a DBK because:

1) You like the convenience of 1-shot colour
2) You like the time saving in capture and processing
3) You like the cheaper cost, without having to buy a filter wheel and coloured filters (expect to add at least $500 onto the price of the camera alone).

They are the ONLY reasons you buy a DBK over a DMK. It isn't a voting exercise - it's completely up to you and your budget, time and experience.

For a beginner I'd recommend the DBK. Learn the art first. With the right equipment and techniques you can get reasonable results fairly quickly, but you'll be surprised how difficult it is to master and do very well.

[ballaratdragons]

. . . or buy astronomy magazines and cut the pictures out :lol:

Be a whole lot easier :thumbsup:

Start at the start with a cheap SPC900NC or 840k ProII. If you aren't happy with imaging, then you haven't spent over $150 to find out. If you do want to advance onto a better but trickier camera, the 900 or 840 will make a great guide camera.

Just don't rush in and want the best, as the more advanced cameras come with more advanced learning.

[Stephen65]

The black and white camera is optimal for imaging the Moon and when used with filter wheels produces the highest quality planetary images, but then you have the cost and hassle of the filter wheel and more complex post-processing.

The colour camera is less suited to the Moon but on the planets gives you the convenience of one shot imaging with no filter wheel needed.

There's a lot to be said for starting off with the much cheaper SPC900NC and seeing if you enjoy webcam imaging, its got a pretty steep learning curve and you'll still be able to produce some excellent images with it.

[Matty P]

I've already tried imaging with my digital camera in video mode shooting at 24fps. I took a couple of AVI's of Mars just from holding the camera above the EP. I read an article on how to process images and found it to be a whole heap of fun. The image was over exposed and bright but after that small experience I needed more. I could see the redish orange of Mars and a ring of blue sorounding it.

So I have had a very tiny amount of experience with a digital camera. :P

What I really don't want to do is buy the 900nc spend between $150 -> $200 then soon after wanting to buy the DBK costing around $350 -> $400. Don’t forget I am on a budget :lol:.

Regards
Matt

[rumples riot]

Despite the current consensus I would recommend this strategy.

If you buy the DBK, you get one shot imaging so to speak. If you buy the DMK and no filters you can still do one shot imaging, only it is in B&W. You will have a nice starting camera. Later you can get a filter wheel and filters. The transition from single shot cams like the 900nc and the DBK is not as hard as people make out. It requires some practice and some patience; if you have them then it will be easy. You can still do nice work with a monochrome camera and learn most of the necessary skills before going to colour with filters. Doing RGB imaging is quite simple, if you just use either photoshop or astra image 2.5max. I use astra image to do my recombine. Keep things simple and with good data; you will achieve nice images.

My vote is the DMK. However, if you are concerned about learning how to do all this, then go the DBK. If you decide you don't like planetary imaging you can always sell the unit.

Choice is yours.

[ballaratdragons]

Between your above attempt, and imaging with a Toucam, D*K, NexImage, DSI, etc, there is 'No Comparison'.

[Matty P]

What is the current price of the DBK 21AU04.AS? Looking around at several sties I've found them ranging between $400 to $540+

Where is the best (cheapest) place to purchase the DBK?

With the USB version of the camera is the USB cable included with the camera?

Regards
Matt

[iceman]

Sounds like you've got the full range of prices already..

Yes the USB cable is included.

[Matty P]

Hi,

I have some quick questions.... :thumbsup:

... I've found out that the DBK outputs data in RAW format. What is RAW format? Can it still be used in Registax?

Is it the same compared to the DFK and the DMK?

Regards
Matt

[turbo_pascale]

The DBK outputs in a number of formats. (BY8, Y800, UVBV)
The one to use with Registax is Y800 (which is a raw matrix from the bayer matrix of the CCD - ie, no colour in the image).

Registax then needs to be told to "Debayer", and use the "GB" setting to get the colour right.


If you try to use any of the other 2 codecs when saving your AVI, Registax will choke. There are ways around it, but trust me, just get it right and it will save you heaps of headaches as well as time.

Turbo

[Dennis]

Hi Turbo

It’s been a while since I used our (Firewire) DBK21AF04.AS, but I seem to remember using the format UYVY when capturing in colour (as displayed on the notebook). This allows a max frame rate of 30fps.

With UYVY I have never had any problems opening these avi’s in Registax and I have never had to select "Debayer", or use the "GB" setting to get the colour right.

Therefore, I assume that the UYVY format is a “Native” format to the DBK whereas Y800 is the RAW format and Registax needs to be “told” how to interpret this?

I think in RAW format you can capture at 60fps as the HW/SW is not required to perform any interpretation of the data stream, whereas what I term the “Native” UYVY is limited to 30fps as the HW/SW is performing some coding of the data re luminance and colour data?

Cheers

Dennis

[Arp]

Hi!
I hope you still follow this thread, as I stand before the same choice as Matt.
As far as I read here, the DBK produces the better quality as the other color camera. But I dont think this is because of the filter, but maybe because of another design of the bayer sensor. Anyway, I already tried the spc900 which gave some good results, but nothing compared to the great images shot with the D*K cameras.
So, I think I will purchase the DBK... Im still not sure if it will be the 21, or 31. Depends on the price :)

But I still got a big question. Right now I am using a 90/910 refractor as a guidingtelescope and the spc900, not modified, as the guidecam. As you can imagine, the amount of guidestars is limited. Will a DBK perform much better? I always wanted to do a good M51... would this camera on this guidingscope find any guidestars? My SPC900 did not.

[iceman]

Hi Arp and :welcome: to IceInSpace!

I use a DMK21AU04 as a guide camera and it picks up enough stars for me to choose when guiding. The will also be fine if you plan on getting the one-shot colour camera.

I look forward to seeing that shot of M51!

[Arp]

sounds good.
Now, I need to think about money... do you know any resellers which ship to germany? I could imagine that because of the low value of the USD compared to the Euro, I could save some money. Is there a chance?

[iceman]

No, i'm not sure. I guess you could simply ask them.

Good idea to shop around though.. even locally here there are price differences which can make it worthwhile to shop around.

[Arp]

Since I never shoped outside of germany, do you have any links to some shops?

I got another question popped up, and I think you know the answer since you use the dmk for guiding. Do you know the program guidemaster? Does it work with a DMK/DBK?

[iceman]

I'm pretty sure guidemaster works with the D*K cameras. I personally use PHD guiding and love it. Very simple and easy to use.

[Arp]

Hi!

I just realized that a D(F)(B)K and the SPC900 have the same sensor, the Sony ICX098BL. So, if they use the same sensor, how comes that the D*K has better quality and costs so much more?

[iceman]

I'm guessing the chipset is better, giving better/lower noise - and of course uncompressed transfer through USB2/firewire instead of compressed USB1.1

[Arp]

Thanks. I will purchase the DBK 21 in about two weeks. Thank you for your help.

I got a quick question. It seems that the clouds over my head are vanishing so I'm prepping another session for tonight. I will use for Mars and Saturn the spc900, not modified. Do you know what codec is best suited? I420 or YUY2?
thx

[iceman]

I used YUY2, it was slightly less compressed.

Do you definitely want to get a colour cam? Why not mono?

[Arp]

I know that the monochrome version would have better quality, but right now I cant afford to buy the camera and a filterwheel and a set of filters. And If I got all things, I think its very hectic to rapidly change the filters to get another colorchannel. And I am not sure if the additional work justifies the better quality.

[Dennis]

Hello, Arp

I have a DMK21AF04 (mono) and a DBK21AF04 (colour), both Firewire and there appears to be a big difference in “sensitivity” between the two units that you may want to consider in your purchasing decision.

When I was recently imaging the Trapezium stars in M42 with the mono DMK I was able to capture at up to 60fps with the gain (0-1024) set at around 500, whereas when I switched to the colour DBK, I had to drop the settings to 15fps with a gain of around 950 and the images were noisier. Unfortunately, I did not try the DBK with a mono codec to see what affect that would have on the image.

At the time, I was using a Tak Mewlon 180 F12 with a Televue x2.5 Powermate which is obviously not a typical auto guiding set up, so if you are planning to auto guide with a typical 80mm F7 refractor this may not be an issue.

Cheers

Dennis

[Arp]

Thanks Guys.
My Decision is now final... Next Week Im going on hollidays for some days, and after that Im gonna order the DMK21. To get colorimages I will use the SPC900 as a camera for the colorinformation, and the DMK for luminance information.. hopefully this will give some nice results, at least until I buy a filterwheel and filters some months later.
Thanks again, I will show you my results :)

[iceman]

Excellent, Arp. Great decision. Are you getting the USB version or the firewire?

Using the SPC900 for colour data can certainly work, you'll just need to do your best to focus quickly and try and match the camera rotation angle as quickly as possible, although you can always rotate in post processing to match them up.

I did a few shots like this back in 2006 (http://www.iceinspace.com.au/forum/showthread.php?t=11442) before I got my filterwheel as well.

[Arp]

I will get the USB version, because I only work with a laptop in the field which doesnt have a firewire port. And I am too lazy to build a connection for the power supply :)

Interesting pictures! This is the thing I want to try in the future.
Could you give a few pointers on how you do this in Photoshop?

I just experimented with it... I took a RGB picture, converted it to grey and used this as luminance and the original as RGB, to simulate my future projects :)
I used the LAB colormode in photoshop, but after realigning the pictures, I didnt have the same colors... anything I did wrong?

[iceman]

Funny you should mention that.. :whistle: Here's some reading for you.

RGB Planetary Imaging with a Monochrome Camera (http://www.iceinspace.com.au/index.php?id=63,468,0,0,1,0)

[Arp]

One question, regarding your setup at the page you linked. great reading btw. :)
If you have the setup: Telescope - Barlow - Filterwheel - Camera, and assuming you use the 5x powermate, you should have more then 5x magnification, right? Because the ccd chip is further away then without the filterwheel.
Its the same setup I have in mind, though I need some tubes to move the barow further away, since I got a new focuser and its smaller than the old one so it can not reach the focus point :)

As an alternative, I could have: Telescope - Filterwheel - Barlow - Camera. This way I would just have 5x magnification, the filterwheel is "long" enough so the Barlow gets into the focus point, but how to I connect the Barlow with the T2 "hole" in the filterwheel? (everything is exactly the same as on your instructionspage).

[iceman]

Hi Arp

Yes, by having the filterwheel after the 5x, it gives me about 6.5x - which is fine with me, more focal length the better (this gives me about 10.5m).

When the seeing is really, really good, I also use an extension tube between the barlow and the filterwheel to give me about 13-14m focal length.

[richter56]

Hello to all,
i'm new to this forum.
I was searching news about DBK-DFK sensitivity because i'm an happy user of a DMK31AF03.AS (1024 x 768) and i was wondering about "HOW MUCH" difference there is between BW and Color versions.
I bought the DMK it mainly for Guiding/Moon /Planets imaging but now i'm enjoying beginning with some unguided 45 seconds exposure DSO imaging from my town (i'm lazy so i stay on my terrace).

The results are pretty encouraging and i'm very happy i bought it.
Should i be disappointed by the color version? (i'd buy 640x480 for budget reasons).
I know that the 640x480 sensor has bigger pixels but they can't fully recover the loss of the bayer mask.
Could someone give me suggestions/opinion?

Regards
Alberto

my DMK31AF03.AS tests:
the DSO objects are all unguided exposition 45 seconds each one with a C8 + focal reducer 3.3

http://www.makina.it/Astro/080214-The-Moon-6353x4326.jpg
http://www.makina.it/Astro/M51-C8-f3.3-TIS-DMK.jpg
http://www.makina.it/Astro/NGC4565-C8-f3.3-TIS-DMK.jpg
http://www.makina.it/Astro/NGC3628-C8-f3.3-TIS-DMK.HalfSize.jpg

[iceman]

Hi Alberto, Welcome to IceInSpace! :welcome:

Those are some amazing DMK deep-space images, just beautiful. Probably the best i've seen from a DMK.

Why do you want to get a DBK? The DMK is much more sensitive as you'd know, because of the bayer filter. Can you not get a filter-wheel and colour filters for your DMK31?

Then you can use it for RGB planetary imaging as well as RGB deep-space imaging.

[Matty P]

Hi Alberto and welcome, :)

There is a significant difference between the two. Monochrome vs OSC, the Monochrome camera will always come out on top.

I've seen both DMK and DBK images side by side and the DMK images easily had the most depth and detail. I'm not saying that OSC wont produce great results but when comparing the two the Mono camera is superior.

I agree with Mike, you should look into getting some RGB filters to use with your DMK31.

My 2 cents...

:thumbsup:

P.S. Your test images are amazing, well done.

[richter56]

Hi Iceman and Matty,
thx for your kind words.
I visited your nice galleries too.
Yes i know that the DMK is superior mainly for the absence of the Bayer mask of course.
That means almost double sensitivity and nearly double definition...and that is really important!

I'm lazy and since i began with a Toucam Pro i remember how easy it was to do color. Direct color always fascinated me LOL...
My first attempts to RGB with DMK are pretty bad and i placed a bookmark on the article about making RGB images that i found here in Icespace. I'll study it carefully.
I have a little ATIK filter-wheel and a set of Baader R G B + IR.
I know that they are entry level filters but i guess that if those filters are used by a RGB expert he could get decent results. Isn't it?

Any suggestion i well accepted...

Thx and regards
Alberto

PS: unfortunately i must forget jupiter for one year or two...
Currently it raise to 20° or so.
Very difficult to do decent images.

[Arp]

HI there!
I got my DMK and as I promised, I finally used it to get a guidingstar and captured M51.
Here as promised :)
http://www.astrob.org/IMG/M51_2.jpg

One question though... If I use the Powermate 5x, do the multiple RGB Channels have different focus points, or is the Powermate achromatic?

[iceman]

Wow Arp, that is really, really good!
What scope did you use? Exposure times?

The powermate is the best of the barlows, but it still can require a slightly different focal point in each colour channel. It's not necessarily the powermate that causes it though - it's more likely the atmospheric dispertion. I've found it also depends on the seeing and the altitude.

[Arp]

thx :)
That was a 8" Newtonian at 1200mm focal length. It was exposed 24x 180s, making a total of about 74 minutes at ISO 800 with a modified EOS 350D and as said the DMK21 on a 90mm refractor as guider.

[Matty P]

Great image Arp, you have done a great job.

What kind of processing software did you use for this image?

:thumbsup:

[Arp]

I used Deep Sky Stacker to stack the images, and then Fitswork zu sharpen it a bit.

[Arp]

hi there.
Im experimenting with rgb images. I read your guide iceman, but how would I align the rgb channels, if I wouldnt use AstralImage? Any way in registax or fitswork, or something else that comes as freeware?

[iceman]

"GIMP" is freeware. Do you have photoshop?

Registax can't combine separate RGB channels into an RGB image.

You can use the trial version of AstraImage and then take a screenshot - I know that's what some people do.

[Arp]

Im not talking about the actual recombining, but the position. My Saturn has in all 4 channels (using L too) a different position, so at first I need to get them aligned so that recombination doesnt end up in some wierd image :)

[iceman]

Try gimp - it will let you shift the colour channels to re-align them. Or, once you have a recombined RGB image, you could try registax with the "estimate RGB" function on the wavelets page.

Or, photoshop.

Or, AstraImage as above - when you recombine the image you can adjust the X/Y offset of each channel.

For combining LRGB, the only programs I would use are GIMP and Photoshop but I know there are others (probably MaximDL and other deep-space image processing software)

[netwolf]

Arp, Steller Magic was one I found that could do RGB recombining. But I could not work out how to do the Offsets that Mike discusses in his article.
Also when you say Saturn is in diffrent position do you mean that your camera has rotated? Or that it is not in the centre of the frame? If frame centre then PPMCentre could do this for you. Mike mentions this in his article
http://www.iceinspace.com.au/index.php?id=63,306,0,0,1,0

Regards
Fahim

[Frewi808]

If you remove the IR cut filter in the DFK21 is is then not the same as the DBK or are they ore differences ??