Jump to content

Banner.jpg.b89429c566825f6ab32bcafbada449c9.jpg

New: ASI533mc-pro


Adam J

Recommended Posts

4 minutes ago, smr said:

Ah thanks for that I should have worded it different... I meant how do just the 2600 and 268 compare to eachother, as I'm interested in an APS-C OSC and may be willing to stretch to 1.5-2k for one... 

I hear ZWO have frosting issues with some of their cameras but QHY don't ?

 

And how does hte 294MC Pro compare to these two apart from the obvious sensor size difference? Half the price I'd imagine if those two are coming in around £2k. I think you can pre-order the 268C for £1,800 at the moment.

In all honestly I think that I would go with QHY in this instance just because of the issues ZWO have had with the cooling on their larger sensors. But I know ZWO have re-designed their camera mechanics from the 071 so this time they may have gotten it right. On the other hand QHY sometimes have issues with their drivers on first release that are then fixed at a later stage. But while you can fix drivers you cant easily fix a sensor chamber that ices up. Looking historically very few issues reported with the QHY168c and lots with the ASI071mc and even the later pro models seem to require desiccant replacement on a more frequent basis than most cameras, I have read a few people saying that they have had to renew the desiccant right out of the box. Not that I own either, I just read lots of forums and have a good memory for facts and figures. 

£1800 for a 268c seems like a good deal to me, QHY often do this as they like to get products out into the market early to drive word of mouth etc, it will go up in price after that. Not sure what ZWO are asking for the 2600 but historically it will be more than the QHY version. 

Adam

 

  • Thanks 2
Link to comment
Share on other sites

1 minute ago, Star101 said:

Having used my ZWO 183mm pro for some time now, I can categorically say the camera does NOT have frost issues. :)

I hear a few people on Cloudynights saying they have problems with their ASI071MC Pro's frosting, can't remember if I've seen anything about the 294 having the same thing but I don't think so... although I have heard about the 294 having calibration issues. 

 

  • Like 1
Link to comment
Share on other sites

1 minute ago, Adam J said:

In all honestly I think that I would go with QHY in this instance just because of the issues ZWO have had with the cooling on their larger sensors. But I know ZWO have re-designed their camera mechanics from the 071 so this time they may have gotten it right. On the other hand QHY sometimes have issues with their drivers on first release that are then fixed at a later stage. But while you can fix drivers you cant easily fix a sensor chamber that ices up. Looking historically very few issues reported with the QHY168c and lots with the ASI071mc and even the later pro models seem to require desiccant replacement on a more frequent basis than most cameras, I have read a few people saying that they have had to renew the desiccant right out of the box. Not that I own either, I just read lots of forums and have a good memory for facts and figures. 

£1800 for a 268c seems like a good deal to me, QHY often do this as they like to get products out into the market early to drive word of mouth etc, it will go up in price after that. Not sure what ZWO are asking for the 2600 but historically it will be more than the QHY version. 

Adam

 

Thanks for that, so basically they are the same apart from perhaps build quality? Same sensor and quality of performance etc?

How about the 294MC Pro, aside from a bigger sensor how does that compare and what are the disadvantages of the smaller sensor? Smaller images and print sizes I guess?

My scope is 430mm.

Link to comment
Share on other sites

7 minutes ago, Star101 said:

Having used my ZWO 183mm pro for some time now, I can categorically say the camera does NOT have frost issues. :)

The ASI183mm pro never have an issue, its a problem for their larger sensors ASI071mc pro and ASI091mc pro due to the sensor being so close to the cover glass and the increased cooling power needed for a larger sensor. I think that in response they have increased the back focus on the new ASI2600mc pro and ASi6200mm pro to more than their normal 6.5mm to combat this issue. So they may have fixed it in doing that. 

Adam

Edited by Adam J
  • Like 1
Link to comment
Share on other sites

20 minutes ago, smr said:

Thanks for that, so basically they are the same apart from perhaps build quality? Same sensor and quality of performance etc?

How about the 294MC Pro, aside from a bigger sensor how does that compare and what are the disadvantages of the smaller sensor? Smaller images and print sizes I guess?

My scope is 430mm.

Its not that simple, I guess that all in all the build quality / finish of ZWO products might be considered better than QHY its just in this instance for their larger sensors the design of the sensor chamber on the QHY seemed more effective than the ZWO equivalent going by comments and reviews.  

In theory if you believe WO then the Z73 should cover a APS-C sensor without issue so the 2600 / 268 are workable for you. Looking at the pixel size then I would say that for you the 3.76um pixels of the 533 and 2600 are a great match to your focal length and more desirable than the 4.63um pixels of the 294. 

At 430mm I think you will get a workable field of view from all of these cameras but larger is always better as you will get an object like the heart nebula into a single frame with a APS-C but not with the 294 and certainly not with the 533 or 183. If you want to make wall prints then the APS-C sensor will make your life much easier. 

Being designed for use in DSLR camera the sensor in the 2600 or 268 is unlikely to have any amp glow. Historically Sony chooses to manage this well for this type of sensor, being of the same technology in a smaller package its also possible that amp glow will be much better controlled in the 533 than the 294.  

Its a balance. 

Adam

Edited by Adam J
  • Thanks 1
Link to comment
Share on other sites

9 minutes ago, smr said:

It amazes me that people are willing to spend £1.5k on the 071MCPro then, unless they aren't aware of the cooling issues.

It is much better (tolerable) on the pro to be fair, the main problem was with the original version, so much so that they had an exchange program when the pro first came out. The pro still works it just seems that you cant cool to the max and you have to expect to change the desiccant on a more regular basis, I guess its annoying but does not totally kill the camera. It would make me favour the 168 over the 071 though. I say this as someone who owns a ASI1600mm pro, the V1 and V2 of that camera had similar issues they fixed it in the pro and I am very happy with mine. I just think in the case of the larger sensors they never quite fully fixed it. 

Adam

  • Like 1
Link to comment
Share on other sites

53 minutes ago, Ken82 said:

charts

So its got very low dark current (no need to cool lower than -10c) and still over 10 stops of dynamic range at 30dB gain, which in turn will give you about 1.2e read noise. Though I would most likely run it at gain 200 (20dB) and 1.3e read noise for a incredible 12 stops of dynamic range and ~8k full well.  

That is very very good. 

Adam 

Edited by Adam J
Link to comment
Share on other sites

3 minutes ago, Adam J said:

So its got very low dark current and still over 10 stops of dynamic range at 30dB gain, which in turn will give you about 1.2e read noise. Though I would most likely run it at gain 200 and 1.3e read noise for a incredible 12 stops of dynamic range and ~8k full well.  

That is very very good. 

Adam 

Not sure if your calcs are right. At 200 gain, e/ADU is about 0.25, right (maybe closer to 0.3). With 14bit ADC, you can get only about 5000e worth of signal, so not really 8K full well. Dynamic range is in fact about 12 (~5000/1.3 = 3780 log that with base two = 11.88) but not sure if that is meaningful in AP - since you get much larger dynamic range by stacking subs (and hence you can target your dynamic range).

Link to comment
Share on other sites

1 minute ago, vlaiv said:

Not sure if your calcs are right. At 200 gain, e/ADU is about 0.25, right (maybe closer to 0.3). With 14bit ADC, you can get only about 5000e worth of signal, so not really 8K full well. Dynamic range is in fact about 12 (~5000/1.3 = 3780 log that with base two = 11.88) but not sure if that is meaningful in AP - since you get much larger dynamic range by stacking subs (and hence you can target your dynamic range).

It matters for saturation on targets like m42 core and means you don't need multiple exposure lengths saturation is saturation irrespective of stacking. I did say 12 (ok 11.88) stops above so am confused by that comment. Also I did not mention e/ADU at any point just read noise at a given gain. You are right about the full well being 5k its a log chart so not the easiest to read at a glance. 

Link to comment
Share on other sites

46 minutes ago, Adam J said:

It matters for saturation on targets like m42 core and means you don't need multiple exposure lengths saturation is saturation irrespective of stacking. I did say 12 (ok 11.88) stops above so am confused by that comment. Also I did not mention e/ADU at any point just read noise at a given gain. You are right about the full well being 5k its a log chart so not the easiest to read at a glance. 

Just wanted to point out that dynamic range is not really something people should concern themselves with.

In fact, neither is read noise provided that it is in reasonable range. Of course, it is better to have camera with lower read noise, but that is much more important with planetary imaging for example where exposure lengths are very short.

With DSO imaging there will be small difference in camera with 1.3e read noise, and one with 2e read noise as total impact can be controlled with sub duration. Let's say that you want to image for total of 4h. If you use 2 minute exposures on 1.3e noise camera, what should be exposure length on 2e noise camera to have equal result (everything else being equal). That is rather easy to calculate. With 2 minute exposures you will have total of 120 exposures, so total read noise will be sqrt(120)*1.3 = ~14.24. If you want same total read noise from 2e noise camera, then you need to shoot (14.24 / 2)^2 = 50.7 exposures or let's round that up to 51 exposures - so your exposure length needs to be 240 / 51 = 4.7 minutes (this calculation is same as (2/1.3)^2 = or ratio of read noises squared).

Due to nature of objects that we shoot and levels of light involved, we should not base our sub duration on saturation point of sensor, and yes for most targets in fact one might want to take a few short filler exposures - to avoid star cores clipping - that occurs almost always and not only on bright targets like M42 - don't see anything wrong with that (not shortcoming of the sensor but rather adoption of certain workflow).

Hence, dynamic range is not really significant in DSO imaging. It is important in daytime photography - where we deal with single shots, and more dynamic range means more options in post processing (exposure correction, displaying things hidden in shadows, etc ...).

In any case, I agree with you that this is interesting sensor, but I would not view it as a competitor to ASI183 - rather as a complement. It allows people to choose between sampling rates / resolutions for their particular setup without too much of a price difference for the same FOV.

 

Link to comment
Share on other sites

32 minutes ago, vlaiv said:

In any case, I agree with you that this is interesting sensor, but I would not view it as a competitor to ASI183 - rather as a complement. It allows people to choose between sampling rates / resolutions for their particular setup without too much of a price difference for the same FOV.

It allows them to make that choice now that they have it, but many will have been looking at the ASI183 as an inexpensive starter camera and choosing it based on price while accepting that it most likely over samples on their system. I see lots and lots of people posting ASI183 images and they are frequently binned 2x2. With this sensor you can now have a camera in the same price range but it will have more optimal sampling and hence be a better choice for most people. So in that way it replaces the 183 in one of its key market segments. In the majority of cases people who may have chosen a 183 will now be better off choosing this sensor. 

Its a good sensor I think its best to leave it at that. 

Edited by Adam J
  • Like 1
Link to comment
Share on other sites

And this is another advantage over ASI183 and ASI294.

image.png.0a236c9f66d125e00d12167f1d89be9c.png

Two dark frames from ZWO's web page. Top is ASI183mc pro and the bottom is the New ASI533mc Pro. No amp glow at all on the 533 and just look at how uniform the dark is. If there was a mono version of this sensor then I would be very tempted to trade in my ASI1600mm pro for one. Its not impossible they might do a mono run in the future just like the 183mono which came out some time after the OSC sensor.

Adam

  • Like 1
Link to comment
Share on other sites

I think a mono 533 would be very interesting, especially given the relatively "clean" dark compared with the 183.  Whilst I can't justify the expense right now I could use another DSO camera, but I'm not willing to splash out on something with such obviously nasty artefacts as the 183 has even if it can be corrected, because I feel it's just wrong for an astro camera in the first place.

James

  • Like 2
Link to comment
Share on other sites

52 minutes ago, smr said:

Is there any reason to consider the 2600 over the 268C? 

The 268C will be cheaper so unless there's a reason to pay more for the 2600.

As far as i can tell the only advantages of the Zwo version will be the integrated hub and more stable drivers. Zwo have struggled with frosting and dew issues on their larger sensors.

Qhy seems to be better on the hardware front but lacking when it comes to drivers. I see the early users of the Qhy 600 are reporting software problems.

I would expect the prices to be very close.

  • Like 1
Link to comment
Share on other sites

20 hours ago, Allinthehead said:

As far as i can tell the only advantages of the Zwo version will be the integrated hub and more stable drivers. Zwo have struggled with frosting and dew issues on their larger sensors.

Qhy seems to be better on the hardware front but lacking when it comes to drivers. I see the early users of the Qhy 600 are reporting software problems.

I would expect the prices to be very close.

Yes I've seen QHY have released at least one driver to fix a problem with the 600 so far. 

Is the reason for the unstable cameras on release due to the vast amount of differing equipment people have and that it's not really feasible to test the camera on all gear before launching it?

Link to comment
Share on other sites

Just read this from a ZWO employee on another forum in reply to Did zwo ever fix their frosting issues?

 

actually such issue only happen to 071 camera because its sensor's package is metal

so it cool too fast and dew will happen on it if the CMOS chamber is not dry enough

 

we already fixed this issue with new produced 071 cameras about half years ago

so if your 071 have such issue just tell us and we will help to fix

Edited by smr
Link to comment
Share on other sites

2 hours ago, smr said:

Yes I've seen QHY have released at least one driver to fix a problem with the 600 so far. 

Is the reason for the unstable cameras on release due to the vast amount of differing equipment people have and that it's not really feasible to test the camera on all gear before launching it?

They do get a bad press on drivers because they don't test sufficiently prior to release and they rely on users reporting issues in the early months in order to identify them and then release updates. The process tends to result in stable drivers after a couple of updates but it dosn't do their reputation much good. All in all though its all ok in the end.  

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.