Neximage 5 as guide camera

[IainMcD]

Does anyone know if the Celestron Neximage 5 as guide camera can be used as a guide camera for DSO long exposures? 

If not, can anyone recommend an affordable guide cam? Thanks!

[Captain Tweaky]

Probably the best known guide camera is the QHY5 which has been replaced - although pre-owned ones are sometimes available on Astro-Buy&Sell. The replacement, the QHY5-II has the same chip on the mono camera but improved electronics. The QHY5-II Colour has a different, smaller sized chip and is primarily intended for planetary imaging. The mono version should definitely be better for guiding.

The QHY5-II has a CMOS Chip as opposed to a CCD chip that is in the more expensive guide cameras - the Starlight Xpress Lodestar for example. The main benefit of the CMOS is the size of chip and it means you have a wider field of possible stars to guide by. It also means it is considerable cheaper. The downside is the sensitivity. What you gain by a larger star field you lose when all the stars near your imaging object are very small and faint. Whilst this doesn't happen often, it can be a little awkward. The QHY5-II is said to be an improvement on the old QHY5 (that I have) though.

I am thinking of changing my QHY5 because of the noise, banding and lack of sensitivity and I have been looking at the various different options there are out there. At the moment the QHY5-II is looking like the best option for me. There have been questions raised about the build quality and in that respect the QHY5 (MkI) that I have is very good. It is the price, the star field and the improved electronics that appeal. I should be interested in hearing from someone who is using one to know what it is really like in use.

I used to guide with an SW ST80 but now use a WO ZS80 - a far superior 'scope. This has improved the visible stars significantly, so it is worth taking the quality of your guide 'scope into account. Hope all this is of some use to your deliberations -

Yours aye - Cap'n

[glowingturnip]

cheap & cheerful, but I use a Meade LPI as a guide cam - takes some getting used to, but works most times for me now

[lensman57]

Does anyone know if the Celestron Neximage 5 as guide camera can be used as a guide camera for DSO long exposures? 

If not, can anyone recommend an affordable guide cam? Thanks!

Hi,

For a guide camera what you need is preferably a large sensor for a wide FOV to pick out guide stars and it would help a great deal if the it was mono and had large pixels for sensitivity . I used an ASI 120 MC for a while and with a 50mm finder I had no issues even though the pixel size was quite small. I guess you could give the Neximage 5 a try and see how it does but my concern would be the size of the captures although most guide software will loose the colour data so it may work.

A.G

[IainMcD]

Hmm. Some interesting information.

The problem is that I'm trying to do this on a budget, I was hoping to be able to us the same webcam guiding as I do for planetary imaging. I haven't actually bought one yet.

[Herbig]

I have a Luminera LM 75 mono I have been using for solar work it seems very sensitive. I was thinking of using this as a guide cam.

I got mine off eBay for £99 but had to make an enclosure for it. Comes with a lens which is removed to be replaced with a "C" mount adaptor. It does have a power supply socket but this is 6v not 12 and anyway it's not needed as it gets power from the USB cable.

I'd be interested if anyone thinks this would work as a guide cam?

[Guest]

You can't beat an old meade DSI for a guide camera, very sensitive and 16 bit too, they do come up on eBay and astro buy and sell.

Regards

MM