DMK21AF04 - first light!

[iceman (Mike)]

Hi guys.

Here's the results of last nights first light with the DMK21AF04.

Everything went as expected, which was good. No real dramas though it is extra hassle.. no doubt about it. Even without filters and filter wheels, extra cables for the hub, extra power required for the hub.

The faster frame rate (I was using 15fps) shows up every little wobble much worse than it did at 5fps with the ToUcam. Even just touching the cable causes a wobble.

My chip has dust donuts on it already, which was a pain last night cause I had to try and avoid them. They're big and black and right where you don't want them.

I still can't use 30fps yet - will try my external HD tonight and see if that helps. The new version of IC Capture helped a bit with the preview mode at least.

I'm using the Y800 codec, on Windows it reports it as FIYUV - don't know if that's normal. Have sent an email to TIS to confirm. These images were captured at 15fps for approx 2 minutes (some less). Gain was about 70%, exposure 1/30s.

The smaller image scale I referred to, I think is due to the position of the chip relative to teh body of teh camera.

In the ToUcam, the chip is sunken in the housing a fair way, and the 1.25" adapter is fairly long, and then I also pulled it out of the powermate as far as it would go.
With the DMK, the chip is right at the front of the housing, the 1.25" adapter is shorter, and I didn't pull it out of the Powermate as far.

So it's not really an issue. By the time I add the filter wheel and other adapters, I think the image scale will come out about the same as the ToUcam.

Seeing was only average (around 5), and I've put the colour ToUcam image on as a comparison.

Processing took longer, cause there's more frames to process! Instead of 600 for an avi, I had 1800! That's a pain too

Conclusions? Too early to tell. Once I can use 30fps I think it'll be better. On some images I do think I can see some finer detail that isn't present on the ToUcam image. No onion rings or compression artifacts either!

Comments/feedback welcome.

[Striker (Tony)]

Looks nice to me...will be nice to see it's full potential and while it's in your hands I'm sure we will get that.

[mojo (Terry)]

Originally Posted by iceman

I'm using the Y800 codec, on Windows it reports it as FIYUV - don't know if that's normal.

Y800 is a pixel format. FIYUV may be the name of the codec using that pixel format.

[ving (David)]

int3r3sting... cant wait fer ya to get the hang of it a bit more. nice start mike

[asimov (John)]

Nice start! The 30 FPS is a must have to get the full benefits. Thats the first thing I noticed in Rumples first DMK images...no onions or compression probs!

[StargazerX1]

Mike,

Congrats on the new camera. I have the 21BF04, don't have any problems with 30fps. I use an older Sony laptop unit 256mB, 1.3Ghz, Mobile Athlon.
I rarely use IC Capture, prefer K3CCD which works fine. Cannot access
gamma control from K3 (since it is not exposed to the DirectShow intfc), but I don't find that a problem, I usually keep it at 1.0. To access gamma control I had to ask the Imaging Source for a firmware upgrade which they emailed me promptly, your camera probably already has that firmware.

I suspect the problem is more the video card or driver, can't be the hard disk. With an exp time of 1/32s I get an avg throughput of about 27fps onto a 4200 rpm internal disk. The preview sometimes freezes for a few frames, but the logging continues ok in K3. One nice thing about IC Capture is you can specify 'non-physical' units which allows exp times like 1/30, 1/31, 1/32 etc. From K3 you are limited to inverse powers of 2. My laptop froze often early on after I got it in 2001, before the DMK, and had to do more research (it was like work!) into drivers, BIOS upgrades and Windows XP fixes. I also have a Color Firewire Unibrain 500C which works ok until I get to 60fps, when the image breaks up in preview.

The biggest problem I have had is focusing in RGB. Although focusing a monochrome camera is easier, especially at low altitudes, the various colors focus at diff spots, and the JMI NGFCM did not provide repeatable positions according to the DRO unit, so I gave up on it and went to the Optec TCF-S. I've written sw for it so I can jump from red to grn to blue with recorded offsets. I'm still using a manual filter wheel so I need the extra help in the short time we have with Jupiter.

Sorry for the rambling, but I guess thats how information is shared. Thanks for posting your great results!

Glenn Jolly
Arizona, USA

[StargazerX1]

Mike,

Forgot to mention, my system also reports codec as FIYUV.

Glenn Jolly
Arizona, USA

[iceman (Mike)]

Thanks for the indepth reply, Glenn. It's very helpful.

I tried K3CCD briefly last night, but it didn't recognise the device. What version of K3 are you using? I'm using version 1 (the free one).

When I selected the WDM driver from K3 it caused an exception and crashed.

If you old laptop can support 30fps, mine definitely should. I'll play around some more tonight, but clear skies and family commitments limit the "playing around" time cause I want to start capturing data!

Did you have to get a PCMCIA firewire card for that laptop? How do you power your camera?

I'm not looking forward to the whole colour channel changing routine.. with the manual wheel and having to refocus, and then wait for dampening time, it's going to eat away at my 2 minute window. I'm using a dob on an EQ platform, which is fairly wobbly at times. I've got a motorised focuser, but it's a home built one with an O-ring around the fine focus knob of a Moonlite CR2.

Certainly no digital readout or presets. That would be very handy.

Thanks again for your reply.

[StargazerX1]

Mike,

I have K3 v 3.0.3.986. Not the free one. Don't remember what it cost, but if it was less than $100US I certainly got my moneys worth. I wish it had an ASCOM intfc so it would support focus control like MaximDL or SBIG CCDSoft.

I have a PCMCIA USB2(2 ports) +Firewire (one 6 wire and one 4 wire) plugin that is powered by an external transformer, 12VDC 300mA. Model is an Adaptec DuoConnect 1422 which shows up as a 1394 Net Adapter #2 on my machine. The manual says you 'may' need an external power supply, for a Firewire or USB2 camera that should read you 'will' need one.

Glenn Jolly
Arizona USA

[gbeal]

Great to hear of others with these cameras, it makes the "hitting of the wall" a little softer, Not much but a little. Thanks Glenn.
I will have to find out why the camera I have will not allow 60fps, where they now advertise that they are capable of.
I agree with Asi, the "artifact" headaches seem less. I shudder to suggest "gone", but seem less.

[Robert_T]

looks great to me Mike! fine detail indeed. glenn's comments re having to focus individual colour channels has me scared again.... just when i was going to handover the credit card?

[gbeal]

Me too. I thought that by focussing with the "clear" filter in place one had the focus for all filters, is this not correct??

[Lester]

I have read somewhere, I think the same place that sell the Atik filter wheels= you can get parfocal filters.

[Robert_T]

Originally Posted by Lester

I have read somewhere, I think the same place that sell the Atik filter wheels= you can get parfocal filters.

I wonder if just focussing on the green channel would get things close enough for the channels either side

[Maurice]

Congrats Mike.. your results from the new camera look very good.
I hope that you've sent some of those images to John Rogers or Hans-Joerg Mettig, because I think that you've captured the merger b/w WSY & WSZ...!!!
Cheers
Maurice

[iceman (Mike)]

Thanks guys.

I'm sure you can get away with focusing on one colour, but it may mean the others are slightly off. That could mean a softer image overall. I guess refocusing on each channel means PERFECT crisp focus.

Thanks Maurice, I sent the image to John and Hans this morning.