QHY5 or QHY5v for AP

[Gina]

I've been looking at these cameras in conjunction with the Baader parfocal LRGB filter set and home made filter wheel as a first step into LRGB imaging while using a Philips SPC900NC LX modded webcam for auto-guiding (for DSO, planetary and lunar). Later on when funds permit I intend to upgrade to something like an Atik Peltier cooled astro camera and then the QHY could be used as guide camera.

I'd appreciate opinions on whether this would be a good idea and whether to go for the QHY5 or QHY5v. With larger sensor and more pixels the QHY5 would seem better and yet it's a tenner cheaper. The only reason I can see for the higher price of the QHY5v is a shutter, which I gather is not wanted or even desirable. There is only a small difference in the pixel size so wouldn't expect much difference in sensitivity but I don't know if it's a better sensor.

Guider Cameras @ Modern Astronomy

[jgs001]

Gina, both camera use CMOS sensors... and whilst the 5v is good as a lunar/planetary imager, I don't think either are designed for long exposure. I did see a mod someone did of the 5 to introduce cooling and it did make a difference.

The global shutter on the 5v is better than the rolling shutter on the 5 when used at high frame rates as you don't get oddities creeping in as conditions change across the frame (seeing for instance can vary in the time it takes the shutter to activate across the sensor on the 5).

I should add, the 5v is doing a really nice job for my as both a guidecam and a lunar/planetary imager, although I struggle with the RGB stuff (so tend to use the 5v for Lum and my SPC900 for colour data on the planets (well Jupiter so far)

[Gina]

Thank you John

I didn't realise they didn't do long exposures. Not worth going for then. How about a QHY6? I see they do long exposures and are cooled.

Just thought... Guiding doesn't need an ST4 port if computer controlled via ASCOM does it, so an imaging only camera would be fine when I go on to use it as a guide camera. I see another thread brewing

[lukebl]

The QHY5 will do long exposures, but I wouldn't recommend it. I have one which I use for guiding and I experimented a bit with long exposures just to see what it can do. It certainly worked, but the result was rather noisy. However, if you persevered with it, and took plenty of lights, darks and flats, you could get reasonable results. And you will still have it for guiding later. It's not good for planetary imaging, as it can't cope with the necessary high frame rate. That's the domain of the QHY5v which is an entirely different beast to the QHY5, despite the similar name.

I did see a forum thread somewhere (not here) which had some very passable DSO images taken with a QHY5, but I've lost the link. Sorry!

[lukebl]

Found the link!

QHY5, some planets & deepsky objects

[Revs]

QHY have a CMOS based planetary cam either coming out soon or recently out which looks very promising. Dion has had one on test for a few weeks now and has had very promising results. Not sure about pricing but I don't think it'll cost the earth.

[Gina]

Thank you Luke and Paul Think I'll pursue other ideas - good to find out before spending my money

[riklaunim]

QHY have a CMOS based planetary cam either coming out soon or recently out which looks very promising. Dion has had one on test for a few weeks now and has had very promising results. Not sure about pricing but I don't think it'll cost the earth.

250 GBP for QHY 132E. And it's also a rolling shutter (but newer) CMOS sensor. I wouldn't call his results good - I'm still waiting to see a "correct" noise free Moon image similar to what QHY5* can do (without using thick sharpening to hide noise and kill fine detail). It the camera can do it - then it's ok. If not - sorry, but junk.

QHY5 example (a lot of them) can be found on astrofotky.cz

[RikM]

I use my QHY5 for lunar / planetary as well as guiding and it is massive step up from a webcam. I haven't tried it for long exposure beyond a quick test but I think it could be fun to play with.

Here's a quick example.

[Gina]

They're certainly some nice QHY5 images though with a 200mm f5 Newt. I guess any mono camera is going to be better than a colour webcam due to the lack of Bayer matrix blocking off a lot of light from the sensor.