DMK Confusion

[matt]

OK.

Can any of you people who've already taken the plunge with the DMK21AF04 mono firewire cam please answer a few questions for me?

First of all price. How much is it just for the camera and whatever comes with it "in the box"???

Second, what do you actually get included in the box?

Am I right in then suggesting all I'll need to get this thing shooting in mono (until I shell out for a filter wheel and filters) is an extra firewire cable, an adaptor and a powered hub?

Many thanks

[[1ponders]]

When you buy the camera, that is all you get, the camera in a box. (approx $610 +postage) You will need a C/CS-1.25" adapter (about $35 - $50 depending on where you get it) that will allow you to shoot just in mono. If you want to get a filter wheel you will need a C-T thread adapter (about the same price). If you don't have firewire in your lappy you will need a PCMCIA firwire adapter, a belkin powered firewire hub ( the camera is powered through the cable and the PCMCIA isn't good enough to do it, even powered) plus at least one 6-6pin firewire cable if you get the hub. Then you will need at least an ATiK filter wheel (about $200) and filters, Baader LRGB $180, Astronomik ~$350

Total cost~$1100 - $1200 all up

[Dennis]

Hi Paul

It seems these PCMCIA cards are quite variable in their performance. I have a Comsol 3 port 6 pin model and a no name one with x2 USB2, x1 at 4 Pin and x1 at 6 Pin IEE1394 Firewire and they do work when powered via a mains adapter.

But, it gets stranger. The Comsol one works when I plug in a 12V 1.66A mains adapter. The no name brand came with a 12V 1A mains adapter and this is the one I used at 1st light, with a 4.5 metre stiff as hell 6 Pin to 6 Pin cable.

However, to get it all to work, I have to boot the IBM ThinkPad with the PCMCIA card already fitted and powered on. The lappy seems quite temperamental with these Firewire PCMCIA cards, but it is a low end model and is also 3.5 years old.

Cheers

Dennis

[[1ponders]]

I know what you mean Dennis. Remember this thread (http://www.iceinspace.com.au/forum/showthread.php?t=16383)?

My no name PCMCIA card has a 12V 1A mains adpater (recommended on the box, don't know how it would go with 1.66A. Eleciticity neanderthal :P ) and there was no way it was going to run the camera. Plug in the PCMCIA card, (mine works plug and play as long as I do it in this order) Card-powered hub-camera. If I plug the camera into the hub first and then connect to the card it won't work. If I plug the camera into the hub and then into the card and put the card in, it won't work.

Bizzare really.

You takin' note of all this Matt? :P

[matt]

Every word, Paul. Every word:lol::rolleyes:

[[1ponders]]

;) :thumbsup:

[davidpretorius]

geez, this all makes the toucam sound easy!

I know Bird has a firefly thingy, and i can now see the need for two computers and 200 miles of cables.

gee these things are complicated!

[iceman]

I can understand your point-of-view (and am jealous of those 5 cameras, especially the large format ones!), however I still believe mono is the way to go if you want to get serious.

We're not only talking about the loss of resolution due to the bayer matrix. The mono + filters also allows:
1) Refocus at each colour channel. I can tell you from experience that each channel has a different focus point. It's minor, but it's noticeable and makes a huge difference to the final result.
2) Adjust settings at each colour channel, mainly gain - so you can end up with a properly adjusted histogram at each colour channel which ensures full dynamic range across the image.

Not to mention processing - even when I was capturing colour avi's (with a ToUcam), I still split the avi into separate colour channels and processed them independantly. It gave me far better results than processing as a colour avi.

So mono+filters forces you to do this. A colour DFK could still be processed independantly by splitting them, so you may as well get the extra benefits as posted above and get a mono+filters.

Yes it's more time, more work, more cost - but we're talking about serious hi-res planetary imaging. If you're just a casual webcam imager, then I'd agree completely about going with the colour camera.

[Dennis]

This is an interesting discussion and brings into play not only the technical issues so well described by Mike, but other factors such as the enhancing of existing equipment and “why we are in the hobby”. A combination of these factors pushed me down the mono + filter wheel path.


I love imaging the Moon, so mono is clearly the best for B&W Lunar imaging.
I already have an SBIG ST7E ccd camera (B&W) and have wanted to take colour images for some time, so this was a great opportunity to purchase a filter wheel to use with both the DMK mono and the ST7E.
The top Lunar and Planetary imagers are using mono, and even though I consider myself more of a general space tourist rather than specialised serious hi res imager, I also like to make use of the best approach and tools in terms of technique and equipment (within my budget).

Cheers

Dennis

[iceman]

Hi Rainer.


Most definitely! No disagreement from me. The problem is, those cameras are much more expensive. Without a doubt, the SkyNyx or Infinity would be my choice especially the large format versions for hi-res lunar photography.

However this thread was about the DMK, which is significantly cheaper but still delivers quality results at 640x480 with very low noise. I believe Matt (the OP) has investigated the other options as well.


As you say that's just one of the factors you'll need to consider when deciding to go mono+filters or colour, along with the decision of how serious you are about getting the best images you can given your equipment, local conditions, time available etc.


I think it would probably depend on what you're imaging, the focal length you're imaging at, and the altitude of the object you're imaging.

I use Astronomik LRGB filters and they claim to be parfocal as well, but at high resolutions (over 8 metres focal length), and especially with objects lower in altitude, the wavelengths definitely require focus at different points.

For deep-space astrophotography, where the focal length is typically much less (1m - 4m), then the difference in focal point may not be so noticeable.

[davidpretorius]

I agree with Mike for the optimal image production of high rez imagery.

I shudder to think what Paul Haese and his 18" mirror and larger focal length is going to be able to produce.

At then end of the day, this is continually evolving
-bigger mirrors
-active cooling of mirrors
-faster and bigger resolution cameras
-faster pipes to record the info on computer or hard disk
-automated focus points for filters and automatic filter changing
-self correcting collimation?

like computers,I think you simply have to budger $1500+ every year to keep up with the latest technology with this particuliar part of the hobby

[matt]

And still am, Mike:lol:

But you make the very valid point about the difference in cost.

I'm really wrestling with the decision to spend around 1K (or just a bit more) for the DMK and filter wheel and filters...or cut straight to the chase and spring for the full SKYnyx 2-1 outfit.

But there is a very, very big financial difference and I'll have to decide whether I am prepared to pay it when the DMK is capable of very nice results anyway.

[Dennis]

Hi Matt

Another option to consider is buy the DMK now, cut your teeth on it for say 12 months, and then sell it to upgrade to the more expensive SKYnix. The experience, fun and results will always be worth it. Arguably the DMK will be around for a while so hopefully there should be no problems in selling it to a webcam imager who wants to step up from a ToUcam to a DMK.

Cheers

Dennis

[matt]

That's definitely one option I am also considering, Dennis:thumbsup:

[iceman]

Most definitely a good idea from Dennis.. There's a big learning curve with mono+RGB imaging, in both setup, capture and processing.