Planetary camera info?

[JB80]

I'm trying to understand a bit better about what planetary cam to purchase down the line.
As I see it the ZWO cameras appear to be a popular choice at the moment both in performance and price in a similar way the Imaging source cams were a year or two back but they seem to be talked about as being a bit outdated now, although still produce great images.

What are the other good options and why?
I'm not sure I totally understand the sensor/pixel/f-ratio side of things either. For example would a different camera be better suited to two different model scopzs like a C11 over a C9.25 or would the same camera be interchangeable?
I ask this because it will be one of these scopes I will be getting.

Certainly the ZWO cameras are affordable but I'm open to spending more if there is a considerable advantage for a different make. I have seen that the Lumeneras appear to be good but truth be told that's probably just the wrong side of my budget.
As a guide I would probably say my max budget would be 500 euro so around 750 AUD.

[Shiraz]

get the camera with the best quantum efficiency and lowest read noise. 8 bits are enough, you don't really need cooling and framerates above 30 fps are useful. The ZWO ASI120 seems to be the most popular at present, but the QHY5L2 and DMK21618/Flea3 are also effective. Lumenera have a bit lower quantum efficiency, but have relatively low read noise and would still be OK for a larger scope. Used to be that you had to spend a lot for a good planetary camera, but the ZWO and QHY CMOS cameras changed all that.

work out the required FNo for the scope/camera combo and adjust with an appropriate Barlow. A simple calculation will find the optimum for any scope and camera http://www.iceinspace.com.au/forum/showthread.php?t=105057 If you get an f10 scope, use a 2x Barlow with the QHY and ZWO cameras or a 2.5-3x with the 618.

[Merlin66]

The ZWO ASI120MM also seems popular for the solar imagers....
I keep hearing about the "dust problem" on these cameras....has this finally been solved?

[JB80]

Thank you Ray, that is a very useful write up and post. It helps me understand a couple of things I had read but never saw the explanation for.
Cheers for that. :)

Ken, they do seem popular all round at the moment. If it doubles as a good solar cam then all the better but I gather most good planetary cams would suffice. I'm just finally coming to terms with my DMK41but it lacks the frame rate for planets.

What was/is the dust issue?

[Merlin66]

http://www.iceinspace.com.au/forum/showthread.php?t=113215&highlight=ZWO+ASI120MM

They seemed to be plagued with dust bunnies......

[traveller]

Thanks for the write up Ray,
You mentioned Powermates are not the same as Barlows due to their lens construction. How would this play into the scenario you just described above? I have a C8 f10 and 2.5X Powermate, does that I mean I should aim for the 21-618?
Also, the old QHY5 and the Orion Starshoot Autoguider use the same chip, would that work with my above set up?
Thanks
Bo :help::question::thanx:

[Merlin66]

Bo,
The Powermate amplification is the same. i.e.x2.5
The Powermate gives excellent imaging and more freedom with the backfocus distances. (The amplification doesn't vary much with distance - it does with conventional Barlows)

[traveller]

Thanks Ken,
Just confirming, the Orion SSAG has pixels of 5.2x5.2, using Ray's formula, I will need f25, so I can use my f10 SCT with 2.5 powermate and my existing Orion autoguider.
Any particular image capture program you'd recommend?
I have RegiStax, but heard Sharpcap is worth trying.
Bo

[Merlin66]

Bo,
I use AstroArtV5 for acquisition with all my cameras - DSLR/ ATik/ QHY5 etc.
It also does all my stacking and pre-processing.
For the DMK's I use the TIS ic Capture and Registax.

[traveller]

Thanks Ken :thumbsup:

[Shiraz]

yep, that's the ideal FNo for 5.6micron pixels. Powermates and Barlows are both fine for this task as Ken says.
The only downside is that the SSAG is pretty noisy compared to more modern cameras - you will need to use darks and flats with it (no major penalty) to remove fixed pattern noise and it will also lack a bit of sensitivity on dim targets like Saturn - should be good on Mars and the moon though.
Firecapture is the capture program I prefer - not sure if it supports the SSAG though.

[rustigsmed]

If you have a cheapie laptop, i'm guessing some camera's may be worse off than others unless you upgrade?

[Camelopardalis]

I bought the QHY, I'm sure I read somewhere that the sensor was the same as the ZWO but I can't find that now :sadeyes: it worked out cheaper than the ZWO too.

Can't say I've had more than a couple of quick sessions with it, the weather has been craptastic here in Sydney since :mad2:

The QHY comes with EZ Planetary and it's easy to use and I find I get the best frame rates with it, but I haven't attempted ROI with Firecapture yet.

[traveller]

I have been looking at asi130, which has 5.2 pixels (asi120 has 3.75) and claimes higher QE http://www.zwoptical.com/Eng/Cameras/ASI130MM/index.asp
Has anyone got any experience with this camera? I can't seem to find too many reviews for it.
Thanks,
Bo

[Shiraz]

the QHY5L2 and ZWO 120 both use the same high performance Aptina MT9M034 CMOS sensor. The ASI130 uses the older MT9M001, which is also used in the Orion SSAG and the venerable QHY5 - it has lower QE than the 034 (55% vs 75%) and seems to be significantly noisier. I have a QHY5, a QHY5L2 and a DMK21-618 and could do a quick comparison of performance in the next few days if that would help anyone - and to make sure that the spec advantages of the MT9M034 carry over to reality.

Dust is a problem for all cameras at f20, where any crud will form very well defined dark shadows and even the tiniest spec of dust will easily cover a few 3.75 micron pixels (eg a human hair will cast a shadow about 50 pixels across). Expect to spend a lot of time meticulously cleaning the chip (or the window) - I use dry cotton buds after breathing on the surface to slightly mist it. ZWO now have a window in front of the ASI120 chip, presumably to help keep everything cleaner.

[traveller]

Thanks Ray that would be great.
Final question colour or mono? I like the convenience of colour but mono gives better resolution right?plus there is the added cost of filters later.
I am leaning towards colour at this stage.
Any words of advice?
Thanks,
Bo

[JB80]

Cheers for all the responses and info guys. Keep it coming. :D

I think the general rule is Mono is better, I agree about the convenience of colour though but I suppose if you are wanting to get the most from it then mono is the way to go. Whatever I go with will likely be mono.

Are the ZWOs and QHYs so good that there is no need to consider anything else anymore?
Again in the interest of pushing things to the limits do other cams perform better.

What about the Ptgrey, ximea and IDS offings which I have heard are pretty good too?

[Shiraz]

colour has lower inherent resolution than mono, but the difference can be minimised with efficient processing. http://www.stark-labs.com/craig/resources/Articles-&-Reviews/Debayering_API.pdf

Asimov was a regular contributor here and was able to produce very high quality images with a colour sensor. If you are intending to get heavily into planetary imaging, go mono for the extra few percent, but otherwise, it seems to me that colour is a viable alternative. The other way to look at it is that a colour camera is now cheap enough that it is no longer such a big deal to write off 30% by selling it used, if you later decide that you want to go mono.

Are the ZWOs and QHYs so good that there is no need to consider anything else anymore?.. on balance, probably yes at the moment. Looks to me like the MT9M034 (ASI120, QHY5L2) is right at the cutting edge with 75% QE and low noise - from limited reading I can't see anything (affordable) to beat it on the horizon. Remarkable that it is also really low cost. The MT9M034 has most of the camera on-chip, so it seems likely that any other makes of camera using this chip will have similar specs. It might also be worth a look at the PointGrey Grasshopper3 with the Sony imx174. It has similar QE to the ASI120 but uses USB3 to support very high framerates at full frame - but it costs 4x? as much and the large pixel count would not provide much advantage over the ASI120/QHY5 for planetary imaging (great for lunar or solar though).

[traveller]

Thanks Ray, I basically narrowed it down to QHY5L-II and ASI120, both in colour as I am just too lazy to do the filtering stuff :lol:
Once I get more time (and money) I will splash out on a mono CCD with filter wheel etc, but that would be a few years away.
At this stage, I plan to use my modded 40D for DSO work, an unmodded Fuji XE-1 for widefield using my Sky Tracker and QHY5 or 120 for planetary work.
Sounds like a plan.
Bo

[Paul Haese]

Been into planetary imaging so long it seems like forever to me. I have had so many cameras now I cannot say with any certainty which is better. I will say this though.

Speed (through put) is critical. Computing performance affects this ability, so ensure you have a fast computer.

I am currently using the ASI120MM, used if for the first time the other night. It worked a treat, relatively clean data. Image scale is very large though compared to the Flea3 I had last year. I had to use a powermate 2.5X which reduces the image scale the further away you move the sensor. Bear in mind though that the image will get dimmer too.

Notable cameras I would recommend are the Flea camera's by Point Grey Research, Imaging Source cameras or the ZWO cameras. I would not bother with Lumenera now. I had one of those 4 years ago and the company has not moved onward with sensors.

I found that cameras with pixel sizes of 5um or thereabouts worked best with an SCT. Using a camera with smaller pixels and in particular very small can provide problems for you.

Best of luck with your acquisition.

[Shiraz]

the rule of thumb shows that the optimum for the ZWO is f19 (= 3.75*5). Looks like you are using the 2.5 Powermate at about 2x to provide about f20 - so that's another validation for the rule :thumbsup:. Minor point, but surely the image will get brighter as you move away from the 2.5 Powermate?

Interested in your comments on small pixels - what problems have you found?

[JB80]

Thanks again Ray and Paul for your insights, very interesting. :)



That would be great if you could do that, I'm sure plenty of people will find it interesting, I would at the very least. Only if you get the time though.

[JB80]

I know it has been mentioned in the thread an I have seen a few things but nothing specific on the zwo forums but in regards to laptop power what would be comfortable laptop specs to run the asi120 with firecapture?

A lot of issues that come up seem to be usb based but that can be got around with a good hub but what in the way of RAM, processor power, harddrive etc.. would be likely to run things smooth?

There is some talk that an intel processor is more user friendly than an AMD or at the least was.

[rustigsmed]

This is something that I'm also interested in knowing. :question:

[John K]

I would be one that would vouch for the Skynix 2.0 Lumenera camera - it was way ahead of it's time and offers a very low noise CCD with really good after sales support. Lumenera has evolved their cameras to USB3 but they are very expensive. For solar work, I think the Skynix 2.0 still has some benefits.

I am finding that the ASI120mm camera offers a bigger chip, it's more sensitive and higher FPS but also depending on capture settings can also be noisy - but more frames can be stacked to overcome this.

So ASI vote from me or if you can get a second hand unit in terms of the other cameras people have recommended.

Go for mono with planetary - don't go colour if you want high resolution.

Good luck with your purchase and hope you get it in time for Mars.

John K.