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SPC880NC SPC900NC Mods.


Coastliner

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Hi All,

I am awaiting delivery of a Philips SPC880NC that has been flashed to SPC900NC. I understand that I will need to unscrew the lens and fit a webcam --> 1.25" adapter, will I also need to buy an IR filter? Any recommendations of suppliers for the adapter and filter? (I'm talking cost effective (cheap) here!).  And I've heard that there are mods that can be done to optimise the camera for astro use, does anyone have any info on this?

Will the camera be any good for DSO or just planets?

Cheers m'dears,

Neil.

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Hi,

First of all You will need an IR filter for planetary imaging, as for suppliers there are some 1.25" telescope adapters on ebay with built in IR filters these would be your cheapest option, if,you were to buy them separately, it would cost you about £23.

As for extra mods, you don't need to do anything else to the camera for planetary imaging, but for DSO you would need the long exposure mod, which is quite difficult to do yourself, well I would not attempt it anyway.

I am not sure on what the longest exposure is on that camera without the long exposure mod but it will be well under 1 second, I think about 1/3 of a second, so to short for real deep sky stuff.

Here is a link to someone on ebay who sells a lot of astro stuff, including the 1.25" telescope adapters with built in IR filter

http://www.ebay.co.uk/itm/Webcam-Adaptor-to-Fit-1-25-Eyepiece-Tube-Holder-with-Built-in-Filter-BNC-Sale-/371289842660?pt=LH_DefaultDomain_3&hash=item56729963e4

Hope that helps

AB

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With the long exposure mod, the camera has to have some intricate soldering done, and has an extra cable added, which is a parallel port cable, so then you will need to convert that to USB unless you have a laptop with a parallel port on.

There is loads of info on the web about the mod, good luck if you take it on.

Regards

AB

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Search in the DIY section for "SPC900 LXmod yesyes style"

The SPC900 is fairly easy to mod, and ends up with one USB cable

Michael

Chris's (yesyes) mod is very neat and works nicely.  It shouldn't be hard if you're competent with a soldering iron, but it does mean completely dismantling the camera, separating the circuit boards and doing a little butchery.  The particularly nice thing about this mod is that it uses a small USB hub and USB<->serial interface inside the box to provide the additional serial lines for controlling the long exposure side, meaning you only need a single USB cable back to the PC, whereas many of the older mods using either the parallel or serial port on the PC needed two cables.  You do need to be careful in your choice of USB<->serial interface though.  Some work fine whereas others don't expose all the required control lines.  There's more detail about it in the thread.

Not seen Chris online for a while, come to think of it.  I wonder what he's up to these days...

James

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No, that's probably fairly sensible :)

I think the case for doing the mod is less powerful now than it was a number of years ago.  These days you can probably pick up a second hand astro camera capable of reasonably long exposures that will do just as well if not better than the SPC900 for less than £150.  And there's the option of using a DSLR which some people already have or older models can be picked up from ebay for less than that.  When people started doing these mods there probably wasn't much available for several times that amount.

James

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I agree with you all, easy is a relative term.


Compared to modding the early Toucams, which was like engraving the bible on a pinhead, the SPC800/900 is easy.


Also at one time the SPC's were £20 from Morgan Computers, and the whole mod could be done for about £10 more.


Which is a lot less than £150 !


Michael

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  • 2 weeks later...

The SPC880/900 now seems to sel used for $100+ AU on ebay for used units which aren't modded. I still have mine in pieces doing the Yes Yes mod.

I alleviated the need to cut the pins on the circuit board connectors by making up an adaptor which both boards plug into and wires redirecting to the switch and custom board instead of hacking the fitted connectors. One day when I don't have a migraine I'll solder onto the minute base of Q3 and assemble the thing again.....One day.

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That's about the same price that they go for in the UK.  In terms of what you get for the money I don't think it's too bad.  I'm not aware of anything in that kind of price range that's comparable.  Not that I've seen for sale, anyhow.  In terms of how cheaply they were once available (I bought mine for £5, or about AU$10), it's quite a lot.

Nice idea to make an intermediate board for the two halves to plug into.  If you're rehousing it as part of the mod then that seems like a very good idea.

James

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Ok, Got my 880 flashed to 900, I have to say I'm pleased with the results, better than I expected. Bear in mind that I am still getting to grips with the image processing, these were taken over the last couple of nights.

post-30409-0-06759700-1428493956.jpg

post-30409-0-95247200-1428493964.jpg

post-30409-0-71449200-1428493975.jpg

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Hi from not very far away!  Have been using the SPC900NC for the past 3 years and am constantly experimenting with the settings.  I use Wxastrocapture - I thought Vlounge pretty poor - so these comments apply to that program, namely use very low or even zero gamma, about 34 for the gain, 100 for the contrast, 75 for the saturation, 10 fps at 1/25 sec  and adjust the exposure so that it isn't too bright - better to be a bit dim if anything.  Take 1500 frames and align and stack 900 in AutoStakkert!2 and the wavelet in Registax 6.  See my blog for the latest Jupiter images.

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Thanks CSM, I have now downloaded wxastrocapture and will give it a go asap.

In the meantime, I am getting a bit frustrated lately with the imaging where I see the image on my laptop as it is being recorded as a nice bright image but the playback is very dimmed. I have uploaded a sample to youtube http://youtu.be/R2McFb-OglI  It is there, honest! You may have to tilt your screen/turn the brightness up to see it. I took several vids last night, thought I was doing well until I tried processing them this morning.

Does anyone have their preferred sharpcap settings for jupiter to hand, using the spc900 camera?

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In the meantime, I am getting a bit frustrated lately with the imaging where I see the image on my laptop as it is being recorded as a nice bright image but the playback is very dimmed. I have uploaded a sample to youtube http://youtu.be/R2McFb-OglI  It is there, honest! You may have to tilt your screen/turn the brightness up to see it. I took several vids last night, thought I was doing well until I tried processing them this morning.

As a rule of thumb, ignore what you see on the screen.  Use the histogram to set the gain instead.

As far as I recall I used to leave all the controls at default, set the fps to 10 and then pop up the histogram and adjust the gain to get it about 75% of the way across.

James

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Last night the seeing was pretty poor and I had to turn up the brightness.  See here for the best result.  For processing use AutoStakkert!2 then Registax 6.  Hoping tomorrow night will be better.

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In the search for better results I was on the point of buying a new camera, something like the ZWO ASI120MC with it's potentially higher frame rates.  However, I was worried that my computers might not cope, especially my netbook which only has a USB 2.  So I was experimenting with my main laptop which does have a USB 3 and discovered that the SPC900NC will quite happily do 30 fps with this.  Tried it out last night, amidst the clouds and mist, really poor seeing. Then found that WxAstrocapture has a problem with files over 2Gb - like it doesn't add the frame count.  This can be overcome using Virtualdub but you end up with a file twice the size apart from the extra time taken in doing this repair.  Subsequently found that using the I420 capture format instead of YUY2 gives a smaller file size, sufficient for a 150 secs, 4500 frame avi, and a smoother capture.  So I won't be buying a new camera for a while!

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Regardless of whether you connect your SPC900 to a USB2 or USB3 port, it will still only do USB1 speeds.  To transfer the image frame takes a certain amount of bandwidth and if you're increasing the bandwidth required by increasing the frame rate, something has to give.  My understanding from reading the Linux driver code is that the camera compresses the image frame using an algorithm that loses data.  The faster the frame rate the higher the compression.  At 10fps you get a small amount of compression on a 640x480 frame and it's probably a fair compromise for getting 10fps.  At 30fps you're losing a fair bit of data.  The only way to fix that is to use a much smaller resolution so there's less data to be transferred.

The reason I420 uses less disk space than YUY2 is also because it throws more data away.  Simplified a fair bit, the video image is split into a "luminance" signal (brightness) and a "chrominance" signal (colour).  There's one value for luminance and two for chrominance for each pixel.  Both video formats use all of the luminance values, but YUY2 only uses two chrominance values (of a possible four) for a pair of pixels whist I420 uses two (of a possible eight) for every four pixels.  By using I420 instead of YUY2 you're therefore throwing away even more captured data and reducing the image quality again.  This works ok for video because the human eye is more sensitive to brightness than colour, but it's not good for imaging.

I'd stick to 10fps and YUY2 and use something other than wxAstroCapture.  SharpCap should have no problems with video files over 2GB as far as I recall.

James

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Thanks James - I had just found the info on the difference between the I420 and the YUY2 on this forum.  What intrigues me is the different way in which the camera 'automatically' connects up on the 2 machines - 10 fps on the netbook usb2 and 30 on the laptop 3.  This suggests that the limitations relate both to the processor and the port used.  Screen resolution is 8 bit so it is always difficult to tell how much is actually lost with the 12 and 16 bit captures.

Yes - I should look at Sharpcap and maybe others, but having mastered and got used to wxastrocapture that means more time spent learning software instead of doing imaging! At my time of life every clear night is precious.

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There may be all sorts of reasons the default frame rate is different, including what else is connected (internally as well as externally) to the USB bus.  I found my SPC900 used to throw errors about lack of bandwidth when connected to a USB2 bus when pretty much anything else was connected (even things like keyboards or games controllers that use almost no bandwidth) which is patently ridiculous, whereas it doesn't when connected to USB3.

You don't have to practice at night, either :)  You can spend time getting the hang of new software during the day if necessary.  SharpCap is actually fairly easy to get the hang of and I used to switch between it on Windows and wxAstroCapture on Linux fairly easily until I decided that at that time there was little point using Linux as an imaging platform.

James

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