Jupiter 3rd Feb from tassie: "Toucam Testing"

[davidpretorius]

Hi All,

some of you may be aware that I have been playing with the toucam pro II 840K.

In summary, Phillips have released the SPC900NC (http://www.home.zonnet.nl/m.m.j.meij...Y/spc900nc.htm) new model that supercedes the toucam pro II 840k

I have read the above article and have tested the ability of using the newer drivers of the 900NC in my toucam. Basically it works, but change them at your own risk!!

But why do it, I hear you ask???
The reason behind turning your 840k into a 900nc is that the new driver has a manual sharpening control and also a new codec (YUY2) for recording the avi, means higher quality images.


In summary:
It is not a usb2.0 device, but I am thinking that it might still be a winner for the following reasons:

1. yuy2 codec = higher quality images
2. manual sharpening of images and contrast control, and if you actually get the real thing ie the 900NC camera, then...
3. the lens of the 900nc will be 4.5mm apparently, so automatically a 30% increase in magnification from the 6mm of the 840k!!

It may not be the one we were all looking for, but definately a worthy upgrade for the 840K and available now at (http://www.telescopes-astronomy.com....am_philips.htm) for $30 more. Not sure on the adapters for prime focus yet???

Now to the images. The first one is captured in raw mode @ 5 fps, note the higher bytes per frame. I had to convert my camera back to a 840k for raw mode!!
Next comes the 10fps, 15fps, 20fps, 25fps.

The seeing was ok say 5 or 6 out of 10. The frames started getting dropped at 25fps and I believe i can see a drop in quality of the 25 fps one.

The 10 fps - 20fps, i am not sure where you draw the line. They all have very similiar bytes per frame, the more frames, generally the better the image if you lift the gain.

I will have to run this test with the std 840k drivers to see if there is a drop off as you go from 10fps to 15fps to 20fps.

The common thought has been to stick at 10 fps and then go to 5 fps if the seeing is good due to compression, but maybe this yuy2 codec may mean you can maintain a good frame quality at 15fps or 20fps.???

What is needed is another great seeing night say 8/10 and then run all tests at once. It is very easy to swap modes on the run using a program called wrmac.

Enough drivel, here are the comparisons and please let me know your thoughts whether there are differences as the frame rate increases

[iceman (Mike)]

Very interesting Dave.. I'll have to try it myself if these clouds go away.

Bit hard to tell about the frame rate difference.. 25fps definitely looks bad, but the others look roughly the same.. really need to see it in very good seeing where the finer features stand out.

nice work.

[iceman (Mike)]

the lens of the 900nc will be 4.5mm apparently, so automatically a 30% increase in magnification from the 6mm of the 840k!!

We use the ToUcam without a lens, so it won't make a difference. The 900 and 840 are using the same chip.

[ving (David)]

looks good dave. i dont know if its me or not but 20fps seems to be a sweet spot for it.

[RB (Andrew)]

I agree vingsta.
The 20fps looks great on my monitor.

[asimov (John)]

20 FPS looks best to my eye as well.

[davidpretorius]

i will be testing, seeing permitted, saturn at 10fps and 20fps with the normal 840k drivers and then the 900NC at the same frame rates. i will compare data size and then also get your learned eyes as to quality!

[davidpretorius]

Originally Posted by iceman

We use the ToUcam without a lens, so it won't make a difference. The 900 and 840 are using the same chip.

so the toucam has a 6mm lens and acts like a 6mm ep when in prime focus and therefore the 900nc will have a 4.5mm lens and act like a 6mm ep in prime focus.

how do they determinie the 6mm in prime focus???

[iceman (Mike)]

I'd forget about the lens Davo - I don't know if you're talking about lens or chip size. We don't use a lens whether it's the 840 or 900.

Afaik, the "6mm" is just a guide for people when they ask "what magnification is the ToUcam". I'm sure there's a formula to work it out (Bird may know it). It might even depend on the focal length of your scope.

[Robert_T]

Hi DP, this is looking VERY interesting indeed. If you can run this at 20fps or even 15fps with the new codec it would be a boon indeed... I note the raw mode certainly doesn't seem to be doing anything extra which is what I concluded. Perhaps if seeing conditions are exceptional, but when that happens I get all panicky and want to get avi on disk and not spend all that time mucking about with settings so the clouds close in when I'm not looking

[davidpretorius]

yeh rob,

hard to tell what is due to lack of frames.

it is looking good here tonight (ie no clouds) so I plane to get a few of saturn.

1800 frames raw @ 5fps
1800 frames yuy2 @ 10fps & 15fps & 20fps
1800 frames std 840k compression @ 10 fps & 15fps & 20fps.

if i have similiar frame qty, then at least there is a common denominator.

when it comes to jupiter then the decision has to be made is the seeing up to it to only capture 450 frames in 90 secs for raw mode???