A Question About Imagers

[Davide Simonetti]

I need to get a new colour CMOS imager for planets, the moon etc. My Orion Solar System imager is woefully inadequate and I can't get much detail with it. My budget is limited to about 200 GBP so I have been looking at two imagers which I think use the same chip and fit my price range: the ZWO ASI 120MC Colour camera and the slightly cheaper QHY5L-II Guide Camera - Colour.

Can anyone tell me which of the two they think is the better buy and whether I will see a better level of detail in my planetary images when using either of them with my Celestron NexStar 127 SLT? Posting any images created with these devices would also help. Many thanks.

[JamesF]

I think you'd find them near identical in performance in all likelihood.  The design of the QHY5L-II is nice, though I'm not impressed that the screws on mine are showing signs of corrosion.  I will probably replace them with stainless ones.    I think perhaps the software support is a little better for the ASI camera and ZWO do seem to be fairly responsive and open to suggestions.

I didn't spend much time imaging with the ASI120MC and 127 Mak as I moved on to using my C9.25 instead, but I did get these ones with the little Mak late in the season for Jupiter last March and just after Saturn's opposition.  I'm sure it's possible to do better.

  

My QHY5L-II is mono though, so I can't offer a comparison with the colour model.

James

[ronin]

They are the same chip, the MT9M034 by Aptina.

https://www.aptina.com/products/image_sensors/mt9m034/

So it likely comes down to what either manufacturer has added to the base product - I would guess they buy the sensor on a prebuilt pcb package and so it would make sense that the underlying electronics is identical, or if not very very similar.

[JamesF]

Oh, also meant to mention that there's an ASI120MC for sale in the classifieds at the moment, for less than the new price of the QHY5L-IIc, and it includes a wide-angle lens.

James

[Davide Simonetti]

I think you'd find them near identical in performance in all likelihood.  The design of the QHY5L-II is nice, though I'm not impressed that the screws on mine are showing signs of corrosion.  I will probably replace them with stainless ones.    I think perhaps the software support is a little better for the ASI camera and ZWO do seem to be fairly responsive and open to suggestions.

I didn't spend much time imaging with the ASI120MC and 127 Mak as I moved on to using my C9.25 instead, but I did get these ones with the little Mak late in the season for Jupiter last March and just after Saturn's opposition.  I'm sure it's possible to do better.

  

My QHY5L-II is mono though, so I can't offer a comparison with the colour model.

James

Thanks James, I'd be very happy if I could get images with that much detail - they look terrific.

[Davide Simonetti]

They are the same chip, the MT9M034 by Aptina.

https://www.aptina.com/products/image_sensors/mt9m034/

So it likely comes down to what either manufacturer has added to the base product - I would guess they buy the sensor on a prebuilt pcb package and so it would make sense that the underlying electronics is identical, or if not very very similar.

Thanks Ronin. I guess if it's the same chip and the electronics are similar then it comes down to build and software support which seems to favour the Zwo at the moment. 

[JamesF]

Thanks James, I'd be very happy if I could get images with that much detail - they look terrific.

The 127 Mak is a surprisingly capable little scope, especially if you take some time to check the collimation (though it is pretty stable) and motorise the focuser.

I started with an SPC900 and I have to admit that I struggled with the 120MC at first.  I think the colour CMOS cameras can be tricky to get the hang of to start with.  They don't behave quite the same way as a CCD and you do have to work with things a bit to find the settings that perform well with your setup.  I don't think the QHY would have been any different though.  It's just quite disappointing when you get an expensive new camera and the first time you go out imaging with it you can't even match what you were doing with the previous one.

James

[Davide Simonetti]

The 127 Mak is a surprisingly capable little scope, especially if you take some time to check the collimation (though it is pretty stable) and motorise the focuser.

I started with an SPC900 and I have to admit that I struggled with the 120MC at first.  I think the colour CMOS cameras can be tricky to get the hang of to start with.  They don't behave quite the same way as a CCD and you do have to work with things a bit to find the settings that perform well with your setup.  I don't think the QHY would have been any different though.  It's just quite disappointing when you get an expensive new camera and the first time you go out imaging with it you can't even match what you were doing with the previous one.

James

I love my little 127...it's beautifully portable - I just took it Sicily and back with very few problems. I'm still scared about adjusting the collmination but the more I read the less daunting it seems. You are certainly right about motorising the focuser - that's something I'd really like to do as focusing can be so tricky and time-consuming. As for the imager, well, I don't mind having to work out the settings...and I just can't afford a decent CCD device at the moment. I just hope that when I do get my new imager I can figure it out quickly enough to capture Jupiter with more than two bands