Autoguider - Colour or Mono

Hans Tucker (Hans) · #1 02-02-2013, 04:04 PM

When it comes to CCD Cameras used for autoguiding application does it really matter if the sensor is mono or a colour

Larryp (Laurie) · #2 02-02-2013, 04:58 PM

Mono sensors are more sensitive than colour sensors

Merlin66 (Ken) · #3 02-02-2013, 05:00 PM

You'll get more "bang per buck" - fainter guide stars, with a mono.

pluto (Hugh) · #4 02-02-2013, 05:31 PM

I'm really interested in this as I'm in need of a guide camera but would love it to double as a planetary cam. The specific camera I'm looking at is the QHY5L-II which in mono I'm sure would make a good entry-level guide cam and in colour would make an great planetary cam.
Does anyone have any real-world experience testing a mono and a colour version of the "same" camera? perhaps a QHY5 mono and colour?
I'm just trying to gauge how different the sensitivity is in actual use as a guide cam. eg is mono 200% more sensitive for guiding? or can a mono cam see stars 2-3-4-? magnitude fainter than colour?

Larryp (Laurie) · #5 02-02-2013, 05:56 PM

Quote:

Originally Posted by pluto

I'm really interested in this as I'm in need of a guide camera but would love it to double as a planetary cam. The specific camera I'm looking at is the QHY5L-II which in mono I'm sure would make a good entry-level guide cam and in colour would make an great planetary cam.
Does anyone have any real-world experience testing a mono and a colour version of the "same" camera? perhaps a QHY5 mono and colour?
I'm just trying to gauge how different the sensitivity is in actual use as a guide cam. eg is mono 200% more sensitive for guiding? or can a mono cam see stars 2-3-4-? magnitude fainter than colour?

Maybe you should talk to Theo at Gama-Electronics. He is the Aust. dealer for QHY. I got my QHY5 mono guider and QHY IMG132E lunar/planetary camera from him, and he is full of good advice.

Merlin66 (Ken) · #6 02-02-2013, 06:55 PM

I don't have a "back to back" comparison with the same cameras -mono-OSC...
But I do know the sensitivity of a OSC due to the Bayer matrix, compared with a mono is around 70% (at best)
We're not comparing resolution...but general QE....binning is also an issue when it comes to guiding...not all (any???) OSC cameras can give say 2 x 2 binning....
I used the original QHY5 for a while, but ended up going to the Lodestar for guiding on fainter stars for spectroscopy.
Hope this helps...