When is an SPC900NC really a 740 or 840 or 880?

[Avocette]

It seems that with a bit of firmware upgrading a number of Philips Webcams are recognised by Windows 7 as SPC900NC. I understand that the various models all used the same Sony CCD chip, but had different circuit boards and different plastic housings. Is there any advantage or disadvantage in using one or other of the models? Does a simple identification parade exist? And when someone sells an "astromodified" SPC900NC how do you know which modifications have been carried out [if you cant ask the person who did the mod]?

Thanks for your help.

[brantuk]

If it's had the LE mod it'll have two cables - one for control and one for data. If it's had cooling added there will be a fan on it. The other mods are more to do with the circuitry inside and as such aren't visible (eg the Amp control mod). The chip change mod gives you a more sensitive b/w chip. There's a mod to fix an eyepiece adaptor so it will fit the focuser tube - but that's more of a hardware thing than a "real" mod.

For a fuller explanation see Steve Chambers website here:

http://www.pmdo.com/SC1.htm and Astronomiser website here:

http://www.astronomiser.co.uk/webcam.htm Hth

[Avocette]

Thanks for the pointers. The '900' I have just bought (in a bundle which was not to be split up) seems to be probably a flashed 880 since it has no snapshot button on either side. It has a good quality (black anodised aluminium with internal baffling) eyepiece tube with a screw in (plastic this time) dust cap. So far my opening up shows that the chip is behind a glass panel rather than exposed to the air with the original threaded lens mount also still in place.

[wuthton]

I believe the majority in circulation are 880's, I've never heard of any particular benefits between the models.