QHY5t Colour Planetary Camera help!

[Specman]

Hi,

I purchased the QHY5t Colour Planetary Camera recently but I'm struggling to get anywhere with it. Its taken me a couple of sessions to get the image on the chip. This I achieved finally by focusing on a distant object during the day then using a parfocal ring on a 12mm illuminated crosshair EP to match focus.

The main problem I have now (which is probably really stupid) is using the camera software. I have not been able to record an image and Jupiter appears as nothing more than an over exposed white blob! I've tried messing about with the gain and exposure without success. I just don't seem to be able to obtain focus.

I'm pretty new to astronomy and even newer to imaging, guess I expected better results from the camera than its able to deliver. I went for it because of its higher resolution and larger chip size compared to the NexImage.

Any advice anyone can offer would be much appreciated, instructions for the camera would be good. The instructions it came with were great for installing the software but a little thin on the ground when it came to using it. It say's its pretty self explanatory, well it is if you know what your doing maybe but my experience tells me that you can never over estimate the intelligence of your average punter!

I got so mad with it this evening I nearly hurled it into orbit! :mad:Or at least out into the darkness, over the hedge into the neighbours!

Yours in desparation!

[jgs001]

I don't know the 5t, I have the 5v though. What software are you using ?, is it the QGVideo software ? It sounds like either, the focus is a little out or the gain is way too high. There are settings in QGVideo to adjust the digital gain and a number of other options that aren't shown on the main screen. Are you connecting the camera direct to the NexStar or are you using a barlow also ?

[riklaunim]

QHY5t has small pixels and for SCTs (~f/10) it does not require a Barlow (adding 2x will likely destroy the image for this camera). As for over exposing - those QHY5* cams can't do very short exposures. I've played with 5v (bigger pixels, "needs" a Barlow) and at f/10 even at lowest gain and exposure Jupiter was overexposed. On f/20 that wasn't an issue.

So for QHY5t start at lowest gain and lowest exposure. If it's still a problem then a polarising/ND filter could help, but I would say it would be unusual for this cam to overexpose at max scope resolution it gets with the small pixels at around f/11. And be sure not to use bin2

[beamish]

if it has "gain boost" turn it off

[Specman]

I am not using a barlow and achieving focus first with a 12mm that I set up with a parfocal ring during the daytime. The scope is near f-13. I'm using the QGVideo software that came with the camera. Riklaunim you have it about sussed I think, its over-exposed even at a low gain and exposure, I've messed about with the settings and at the lowest settings its off the screen, but all I seem to get is a white blob no matter what I try. Silly question what is bin 2?

Question for JGS001: Do you know how to use the QGVideo software?

Thanks

Mark

[riklaunim]

I've used Nebulosity for 5v. Bin2 - the camera has the option to make 2x2 pixels count as 1 so smaller size and 4 x signal.

[beamish]

If it's over/exp don't use the bin feature.

Have you unchecked "gain boost" ? ...and "enhanced Noise reduction" ?

Have you posted a Q on the QHY forum -perhaps someone else has experienced this prob?

One more thing, Are you attempting to use it at full frame or are you having this problem in the ROI mode 640x480 planetary mode ? At this frame/resolution you ought to be able achieve higher fps/exposures