DMK Astronomy Cameras – new webpage

[Dennis]

Hello,

Just thought I’d mention this as a new post, to let DMK users and potential users know that The Imaging Source (http://www.astronomycameras.com/en/products/)have launched an “astronomy version” of their DMK Firewire cameras.

It appears that the “astronomy version” is a firmware upgrade and that

“…it requires a valid serial number in order for it to be installed. Unless an astronomy FireWire camera advertised on this web site is installed on your system, this software can neither be installed, nor used.”

There is a nice FAQ and even a Forum available from the webpage (http://www.astronomycameras.com/en/products/).

Cheers

Dennis

[2020BC]

The top planetary imagers seem to be switching to this camera. Why? What are its properties that make it superior to say a Mintron or similar?

[gbeal]

COST??

[Dennis]

Value for money, published results and performance are what made me order my DMK.

Here is my journey through the realms of Lunar and Planetary imaging:

Meade LPI - $199 (including comprehensive software suite).
Philips ToUcam - $159


Current purchase:

Imaging Source DMK - $610


Next steps?

Lazzaroti camera - ? $750 (guess)
SkyNix camera - $1200


Each camera is a step up in either technology (CCD vs. CMOS), less noisy design/circuitry, faster uncompressed frame rates, etc. The DMK sits in a sweet spot of affordability and good performance.

Cheers

Dennis

[rat156]

So whats the difference between the 21AF04 and the 21AF04.AS, apart from about $300 AUD? and the .AS

Can someone with one of the non .AS versions verify that the plain one does all the stuff that the .AS one does?

If it does, I'd be a little peeved, I was seriously considering getting one of these for planetary work, nut if they're trying to rip us off like everyone else...

Cheers
Stuart

[davidpretorius]

me thinks Skynx like damian peach???

[[1ponders]]

To start with if you check the .AS specification here (http://www.astronomycameras.com/en/products/firewire-cameras/mono/dmk21af04as/)you'll see it has a max exposure of 60 min

If you check the non- AS specification here (http://www.theimagingsource.com/en/products/cameras/firewire_mono/dmk21af04/specification/)you'll see it has a max exposure of only 30 sec

[rat156]

But, correct me if I'm wrong, these are planetary cams.

I suspect the results for DSO's would be pretty average, as this isn't a cooled CCD, though over 30s may be useful for some of the bright DSO's.

So for planetary only work would you recommend the non-AS version as it's almost half the price?

Cheers
Stuart

[matt]

What's the difference between the BF04 and AF04?

[mikey7]

The colour DFK 21AF04.AS has the same ccd as the ToUcam 748/840/900. Faster frames per second will get you more images in moments of steady seeing comparred to the Toucam, especially the faster rotating planets so can stack more without the planets rotation causing too many problems.

Cheers
Mike

[ronnierigel]

OK there's good theory behind these more expensive camera but this hobby is not immune from commercial pressures just like everything else we do.

Has anyone done/seen a head to head comparison between a toucam and one of these "higher end" imagers taken using the same type of scopes from the same location using similar porcessing??? The incremental gain in quality may not be justifiable for the cost!!

I have surfed thru the internet and seen some fantastic shots using the toucam and some ordinary ones using the DMK......is seeing the manufacturer's x factor for selling!!

ron

[iceman]

Ron i'll post a comparison later - I upgraded from the ToUcam to the DMK and did a side-by-side when I first got the DMK. Will post in a few hours, just in the middle of something.

[Dennis]

Where are you getting the AU$300 price difference from?

The website quotes the DMK 21AF04 at US$390 and,
The DMK 21AF04.AS at Euro 330.

A quick currency calculation reveals a price difference of only AU$56.00

US$390=AU$493
E330=AU$549

Cheers

Dennis

[rat156]

Hi Dennis,

Thanks for that, I should have examined the website more closely, I thought it was quoted in GBP, not Euro. Now for an extra $56 I might just stump for the new one!

I'd like to see a comparison between the single shot colour and RGB on the monochrome, anyone?

Cheers
Stuart

[[1ponders]]

I ordered a DMK21AF04 and it turned up this morning. Only it wasn't the camera I ordered. I was sent the DMK21AF04.AS. :shrug: Pleasantly happy I must say.

Has yours turned up yet Dennis???

[matt]

Bonus!!!

Happy shootin', Paul.:)

How do the DMKs perform on DSO?

[Dennis]

Hi Paul

I just took a 'phone call from the supplier saying that he accidentally sent my DMK to you and would you please deliver it immediately to me in Brisbane and your box brownie will arrive tomorrow. :P

When I spoke with Matt yesterday, we anticipated a delivery on Friday at the earliest, but more likely Monday. Put yours to good use in the meantime and iron out any bugs before I get to use mine. :thumbsup:

Cheers

Dennis

[[1ponders]]

:lol:

Bug 1.

My powered PCMCIA card won't power the camera (power is definately getting to the card) so it looks like I'll have to go and get a hub :(

[[1ponders]]

I'll let you know Matt.....just as soon as all this cloud clears :lol:

[Dennis]

Hi Paul

What make/model is your PCMCIA Card?
Does it have 6 pin connectors or 4 pin?
Is it powered internally or is there a power socket on the card for an external power supply?

Cheers

Dennis

[[1ponders]]

Hi Dennis.

No name brand :P

It has both 4 and 6 pin plus has an external power point. Power required is quoted as DC 12V/1A power input.

[Dennis]

If it’s any consolation, I have the Comsol 3 port Firewire PCMCIA Card that has 6 pins and am having a few problems connecting a powered Firewire external HDD to it.

The HDD is a powered 300G Maxtor Firewire/USB2.0 drive and when I connect using Firewire (via the Comsol 3 port Firewire PCMCIA Card) or USB through the native USB2.0 port, the drive is recognised and can be browsed in either mode. All is good.

In USB2.0 mode, when I do a backup it screams along and works perfectly.
In Firewire mode, when I do a backup or copy an AVI in File Explorer, it falls over and I get a "Delayed Write Failed" error message and lose the drive from the system, which requires a reboot to fix.

From reading various MS Help Sites and other Forums, it appears to be more likely a problem with my 3 ½ year old Notebook rather than the PCMCIA card or Maxtor HDD. Ah well, I’ll keep plugging away, at least I have the USB2.0 option to fall back on for the HDD.

Cheers

Dennis

[[1ponders]]

I'm having a really horrible feeling here. Dennis how do I find out what type of video/graphics card I have?

[h0ughy]

go and have a look at the hardware configuration in control panel, system - harware and note the graphics hardware, also memory allocation from system

[[1ponders]]

Where to from here H0ughy?

[iceman]

I told you that mr ponders!

I got my Belkin one from www.streetwise.com.au for something like AU$85-$90. It arrived in 2 days. Order it today! :)

I wouldn't worry too much about your video card. My laptop has an old internal Intel thingo (old Dell D600) and runs the DMK fine.

[iceman]

Click on "Display Adapters".

[[1ponders]]

Cheers, thanks for that Mike. I thought it might have been the case. I'll pop down the coast tomorrow and pick one up.

[Dennis]

Hi Paul

Here is my view of Device Manager.

Matt recommended the Belkin hub when I placed the purchase so I should receive one with the goods when they arrive.

Here is the link to the Belkin 6 port Firewire hub (http://catalog.belkin.com/IWCatProductPage.process?Product_Id =198532).

Cheers

Dennis

[[1ponders]]

Ok here's mine now that I've found it.

[Dennis]

Astro-lappy....what kind of name is that for a sleek, shiny, hi-tec toy?????

[[1ponders]]

:lol:
:D

[iceman]

Hi Ron.

Here's a few images I took when I first got my DMK. Same telescope, same conditions, same processing.

Remember the DMK was taken mono (no filters). A red filter may have made those mono images look even better.

I know for a fact through experience, the DMK has much less noise and is more sensitive than the ToUcam. It also has less artifacts due to being uncompressed data at higher frame rates.

It also has more resolution as it's using the full 640x480 resolution in each colour channel, as opposed to the bayer matrix of the ToUcam.

HTH

[rat156]

OK now I have a question.

Why do you say that the monochrome has more resolution? The Bayer matrix is simply filters over the CCD, and although that means each pixel can only read one colour, at the pixel scale you're talking about it really doesn't matter. The de-Bayering software (either in camera or on computer) works extremely effectively at interpolating the data and generating a luminance channel. Remember that it's only the luminance channel that infers resolution to the human eye.

Now using my 8" Meade as an example...
Theoretical limit is 0.7", in order to get high resolution images this has to be covered by more than one pixel, with the small pixels of the DMK cameras (5.6u), even at f10 the pixel resolution is 0.58", with a 2.5x Barlow, it's 0.23" and with a 5x it's 0.12". So the smallest detail I can expect to resolve is 0.7", which if I'm working at f50 is covered by at least 25 individual pixels. I think that's oversampled anyway.

Please feel free to correct me...

Cheers
Stuart

[Dennis]

Less of a correction, more of an amplification.

Two of the perhaps best known high resolution Solar, Lunar and planetary imagers, Damian Peach and Thierry Legault have written some interesting stuff about hi res imaging. I’ll just quote an important finding from each author as follows:

Damian:
"As mentioned above, contrast of the features we are looking at is critical to how fine the detail is that we can record. The Planets are extended objects, and the Dawes or Rayleigh criterion does not apply here as these limits refers to point sources of equal brightness on a black background. In fact it is possible for the limit to be exceeded anywhere up to around ten times on the Moon and Planets depending on the contrast of the detail being observed/imaged".

Thierry:
"In favourable conditions, details whose size is under this stellar resolving power can be recorded, as in the image of Saturn in the home page: the size of the Cassini division is about 0.7 arc second at the ends of the ring, and about 0.3 arc second where the ring reaches the edge of the planet. Nevertheless it is easily visible on the image, even if the theoretical resolving power of the telescope (9" Schmidt-Cassegrain) on double stars is only 0.55 arc second".

Damian’s site:
http://www.damianpeach.com/simulation.htm

Thierry’s site:
http://legault.club.fr/what.html

Both make an important distinction between:

The resolving power of a telescope and,
The minimum size of the details visible with the same telescope.

Indicating that the classical formula for the Dawes limit R=116/D (R in arcsecs, D in mm) is less relevant in hi res imaging of planets as compared to double stars, from which the formula appears to have been derived.

I think some of Mike’s own hi-res DMK images e.g. the Alpine Valley clearly showing the thin, sinuous rille running along the middle, exceed the Dawe’s limit or Rayleigh criterion for his system?

Cheers

Dennis

[matt]

Does anyone have a link to Paolo Lazarotti's website, if there is such a thing?:)

[rat156]

Hi Dennis,

Thanks fopr the info, both articles point to other things in the setup have far greater effects than the Bayer matrix would.

I think the greatest advantage of the DMF/DFK/DBK line of cameras is the up to 60fps. Atmospheric turbulence has a much more detrimental effect on images than virtually anything else, and it's something most of us can't avoid. The effect can be seen in Mike's images posted above, comparing the Toucam and the DMK. The Toucam images are at 5fps, the DMK are at 15fps. Although Mike hasn't mentioned the actual conditions he took the pics under, he's also said that the DMK is more sensitive, so the exposure is probably shorter, better to "freeze" the atmosphere.

I have the same effect when using an LPI. I get nice sharp pics when using the scope at f10, sometimes at f25, but at f40 things go blurry, in much the same way as Damien's simulation of atmospheric turbulence. The optics are the same (except for the Barlow/Powermate) the only thing that's changed is the f-ratio of the scope and hence the exposure time. It's very frustrating, so I'm looking into one of the DMK/DBK/DFK cameras. So this discussion has come along at just the right time!!

Cheers
Stuart

[ronnierigel]

Thanks Mike for posting your images and everyone else for contributing to a great thread!

This is exactly what I wanted to see and read about---it's an interesting subject---theory versus practice.

Mike, you're a great planetary imager with the toucam. I can see the incremental gain the DMK has given you however.

For people like me where seeing is generally average it's now a matter of cost versus gain! (as always!!).


Sounds like the cost is not just the camera but also the hardware!

regards

ron

[Dennis]

And don't forget the extra time in post capture processing....3 AVIs, R G B to punch through Registax then combine and align, disk storage for large file sizes, modern computer to cope with large data files from Firewire devices, etc.

Cheers

Dennis

[bird]

Stuart,

as someone who has done the full journey from ToUCam -> cheap mono camera -> expensive mono camera, I can say that the difference is like chalk and cheese. There is absolutely no way I would go back to a colour camera :-)

The advantages of a mono camera are numerous:

- You use your own filters rather than the cheap and nasty bayer matrix that's built into a colour camera. This is very significant. The bayer matrix is designed for casual video-conferencing (daytime) use, and not only loses some light but has awful response curves. On the other hand if you use good (expensive) dichroic filters with a monochrome camera then you can get nice clean bandpass figues and high (close to 100%) transmission.

- Colours typically come to focus at slightly different points due to slight chromatic effects of barlows, powermates etc. In a colour camera you just have to put up with a fuzzy blue channel if you want a nice sharp red channel, but with an electronic focusser you can set focus positions for each channel seperately. This is a big big win in my experience.

- mono cameras typically have a 16bpp data mode, allowing you to get a lot more dynamic range than colour cameras that are almost always stuck at some sort of compressed 8bpp mode.

- ... and because they have a 16bpp data mode the onboard electronics are usually much better quality, ie lower noise, so you capture more useful info at higher framerates and higher gain. As most planetary people will tell you: brightness is king. The brighter something is, the shorter the exposure you can use, and the better final result you will get.

- You can choose to use no filter for a luminiance-only image, and get 3x or more brightness compared to a colour camera where this is not possible.

- And , of course, there is no bayer matrix to reduce your colour resolution. This is very important on planets like Jupiter and Mars where a lot of the interesting detail is in colours like red and blue, and not in green.

ps you can forget the standard formulae for resolving limits etc when doing planetary imaging - it's very clear from images taken by all the top people that the practical resolving power is something ike 10x better than the dawes or rayleigh limits. Remember they were set for visual observing on double stars, not for planetary resolving with powerful computer-assisted algorithms.

cheers, Bird

[matt]

Some good info there, Anthony:thumbsup:

I can feel the irresistable pull of a monochrome CCD cam:scared:

[[1ponders]]

:lol:

[Gasman]

Hi Guys
Just to butt in here. I bought my DMK21AF04 a few weeks ago and have just done a `free` firmware upgrade to the .AS version so can`t see where a price difference comes in?. I think they are both priced at 330 euros over here in the UK ie about £280.
Steve

[rat156]

Yeah, me too...

I have always wanted an answer to the questions I asked, now I have the answer...

So it's time for another question.

Anyone know how I can attach the cfw8 from my sbig setup to one of the DMK's?

Cheers
Stuart

[[1ponders]]

cfw8 - colour filter wheel ?

If so what thread does it have.

[rat156]

Yes the SBig CFW8.

It's actually bolted onto the front of the ST-7, but I think that there's t-thread on the inside.

I have since realised that I can't control it without the ST-7 inline as well, so looks like I'm up for another filter arrangement.

Cheers
Stuart

[Gendo]

Yes, the AF04 and AF04.AS cost the same in USD.

This afternoon was frustrating for a while after I finally got a firewire 6-pin PCMCIA card. I was also having initial problems powering the camera with the firewire PCMCIA card, but it turns out that the included supplement power (via USB cable with a power plug on the other end that plugs into the card) is insufficient at only 5 volts. I crossed my fingers and plugged a wall outlet DC transformer into the card that is set to 12 volts. The camera was instantly recognized. I turned down Windows attempt to install a generic driver, and installed the supplied driver. Everything works just fine now, so I'm eager to give it a first light.

For the record, my laptop is only a 667Mhz/256MB computer with a slow 4200rpm hard drive, and it dropped zero frames @ 30fps and Y800/unspecified.

[[1ponders]]

Nice going Justin. I had a few problems as well, getting it up and running reliably. (see DMK - Connectivity issues (http://www.iceinspace.com.au/forum/showthread.php?t=16383))

[Gendo]

I also gave 60fps a try using Y800. The live window was choppy and froze at moments, but the actual avi was smooth and dropped no frames. It is doubtful I'd use that framerate on anything except maybe the Moon.

Kind of amazing for this little VAIO C1VPK laptop since it only has an 8MB 256bit video card. A lot of DMK users said I should upgrade my Win2K Pro to XP, but that would just consume more system resources. :P

So overall, a PC with stats like mine is the real bare minimum for these cameras.

[bird]

5 volts? Hmm, the firewire spec is 9 to 30 volts @ 2 amps, so no wonder the usb port doesn't cut it - I think it's 5v @ 0.5 amps.

cheers, Bird