zwo asi 174

[sooot]

599 oh my god. ROB DOGS. last days for ordering off zwo for their cheaper price

[Amra]

Exposure is obviously tied to fps, so the maximum exposure you can use at 125 fps is 1000/125 = 8ms. Even less at higher fps as is easy to calculate. This means that if you want to keep very high fps for planets you'll have to tinker with gain & gamma if the planet isn't appearing bright enough.

[Astroboffin]

It's best to replace the HDD with the SSD and then reinstall the operating system & drivers (or clone the old disk onto the ssd, if you know how.) because your particular laptop only has 1 usb3 port, just like mine. I suppose it's possible to use an SSD externally, but then you need 2 or more USB3 ports and you lose the benefit of having a fast system running the OS of the SSD.

I find great offers on SSDs on ebay from time to time, Samsung EVO 840 are a nice brand that you sometimes find cheaply, I would get a 250GB sized one as a mininum.

You don't need to put the OS on the external drive, just set a folder on the external drive as the capture location, this should then bypass the interan drive and save all your data to the external USB 3.0 SSD drive.

AB

[rwg]

Exposure is obviously tied to fps, so the maximum exposure you can use at 125 fps is 1000/125 = 8ms. Even less at higher fps as is easy to calculate. This means that if you want to keep very high fps for planets you'll have to tinker with gain & gamma if the planet isn't appearing bright enough.

Agreed, you need to turn the gain up to bring the exposure down. The testing I've done with the camera indicated that it had a *lot* of scope to turn up the gain, much more than the ASI120MC I think. Sam has confirmed on Facebook today that the camera has 0-40db of analogue gain, which is apparently higher than most other cameras with the same sensor.

cheers,

Robin

[michael.h.f.wilkinson]

Interesting stuff. I would almost always prefer boosting exposure time over gain, but having more gain to play with is definitely nice.

Mine might arrive today, it seems

[michael.h.f.wilkinson]

Forecast for tonight is clear. Sunday afternoon should be clear too

Hard to believe some kit might be arriving

[Amra]

You don't need to put the OS on the external drive, just set a folder on the external drive as the capture location, this should then bypass the interan drive and save all your data to the external USB 3.0 SSD drive.

AB

This is true, and of course you wouldn't put the OS on the external drive.

The problem is that his laptop only has a single USB3 port (according to what I could check on google) and that has to be reserved for the camera itself, so there is no USB3 port left for the external SSD, thus you are forced to use the SSD as an internal drive with OS etc. on it.

Maybe as another solution the CD-ROM can be replaced with with an SSD in a CD-tray, however I don't know if the interface on the CD-ROM will run at SATA3 speeds.

[JamesF]

It doesn't come with a suitable lens (presumably because of the larger sensor) so I have only been able to see a dark frame   (The CS lens that comes with the ASI120's won't focus).

If the CS lens doesn't focus I'd guess it's probably because thanks to the deeper body the focal plane of the lens is too far in front of the sensor.  A C-mount lens might work though.  I'll see if I can find one and try it.

James

[JamesF]

Yup, a C-mount lens works fine.  A quick test with my desktop (without saving the files) is giving me about 110fps flat out at full resolution but with quite a few frames dropped, and around 310fps at 640x480.  (This is using oaCapture on Linux with today's release of the SDK.)

James

[Astroboffin]

Whenever I use my camera, I always adjust the frame rate so there are zero dropped frames, I can get higher rates but with loads of dropped frames, so which is best, low fps and no dropped or high fps with loads dropped, I would have thought the first one.

Or am I missing something here....

I see people are getting good rates with this new camera, on USB 3.0, but are those results with dropped frames or not??

AB

[JamesF]

I see people are getting good rates with this new camera, on USB 3.0, but are those results with dropped frames or not??

These cameras have no direct control over the frame rate.  You get them as fast as they'll come given the exposure time.  The machine I'm testing on at the moment is my normal work desktop without any attempt to optimise it for image capture, but I can get 310 fps at 640x480 with very few frames dropped and whilst there are a fair few at 110fps at full resolution, if I increase the exposure time to give 100fps I get no significant number of dropped frames at all.

James

[michael.h.f.wilkinson]

Sounds really good.

[Radders]

I see on Amra's photo there is a box for a 174MC version. I take it that is the OSC?? Will that be good for Planetary?

[JamesF]

I see on Amra's photo there is a box for a 174MC version. I take it that is the OSC?? Will that be good for Planetary?

I assume it must be the OSC model, yes.  Certainly it looks that way from the website.  I'd be disinclined to order one specifically for planetary use until a few people are posting images to be honest.  It should be well-suited to solar and lunar imaging, but the pixel size makes it a bit of a challenge for planetary compared with, say, your QHY5L-IIc.  It should be easier with the C8 than with many large newts though.

I'm not saying it won't work well.  I honestly just don't know.  It may be that the smaller pixel cameras are just so much easier to use.

James

[Radders]

Cheers James, just thought I'd put it out there. I'm not really up how image sensors and pixel sizes really work. Something I must read up on more and get my head round.

I wonder how long it will be before the colour version comes out for testing.

[riklaunim]

but the pixel size makes it a bit of a challenge for planetary compared with, say, your QHY5L-IIc.

Thats odd how pixel size becomes a problem. When 5.6 um ICX618 was dominant the smaller pixels of QHY5L-II and ASI120MM were a concern. Now, when smaller pixel cameras are popular - bigger pixels are a "problem".

Pixel size is irrelevant for usage. You just pick the correct Barlow and that's all. Also there are already planetary photographers that use IMX174 based cameras and the difference/advantage over MT9M034 is clean uniform background noise - no fixed pattern noise - which can be annoying on some imaging setups.

[sooot]

Cheers James, just thought I'd put it out there. I'm not really up how image sensors and pixel sizes really work. Something I must read up on more and get my head round.

I wonder how long it will be before the colour version comes out for testing.

Its already out tester price with zwo finished today

[JamesF]

Thats odd how pixel size becomes a problem. When 5.6 um ICX618 was dominant the smaller pixels of QHY5L-II and ASI120MM were a concern. Now, when smaller pixel cameras are popular - bigger pixels are a "problem".

I said it was a challenge, not a problem. I've certainly found it far less fuss and much quicker using an ASI120 and 2x barlow than it was with the SPC900 trying to work at the high focal ratios desirable for that pixel size. I wonder how those people working with the large f/4 to f/5 dobs might compare the difficulties of using the two different cameras?

Pixel size is irrelevant for usage. You just pick the correct Barlow and that's all.

It's not really all though, is it? For a start there may not be a barlow (or other combination of optics) that does what you need for your scope, or changes/compromises may need to be made elsewhere to make everything work. And the process of re-centering the image after you've put a 2x barlow might well be far easier than if you've just added a 5x barlow because the error is multiplied so much more, though larger overall chip sizes are certainly helpful there.

I suspect that some people will find the ASI174 works nicely for them as a planetary camera and I'm certainly going to give it a try myself, but there may well be others for whom it doesn't work so well because it doesn't suit the kit they have and they may prefer to stick with a camera with smaller pixels as a result.

James

[Astroboffin]

I just get the impression sometimes that when a company that is producing camera fit for a purpose. Ring out a new model for more than twice the price, people automatically assume that it is going to be twice as good as the one before, but this is not always the case.

But then one person decides to buy, and then another and so on.....

I personally have not got the money to be able to do that, just on a chance it may be better than what I already have.

I think I will wait for a few months and see the results you guys are producing, and see how much better they are, than what people are currently getting, then decide whether to part with the £599 or not........and my guess is a resounding not, or my bank manager, AKA the wife will probably kill me...

Look forward to seeing the results from you guys who have taken the plunge.

AB

[JamesF]

And of course there is the consideration that if the ASI174 should turn out to be an excellent planetary camera for lots of people, there may be a load of used ASI120s on the market.  And even if they turn out not to be as good as the 174, they're still a long way from rubbish

James

[Astroboffin]

And of course there is the consideration that if the ASI174 should turn out to be an excellent planetary camera for lots of people, there may be a load of used ASI120s on the market.  And even if they turn out not to be as good as the 174, they're still a long way from rubbish

James

Now that's a thought, I wouldn't mind one of the 120s cameras, I would consider one of those if any of you who have got the new 174 have one and want to part with it now....

Let me know....

Regards

AB

[Luke]

Well a camera is more than just comparing the best pictures taken with two different cameras. I am not expecting this camera to thrash the pants off of my Grasshopper 3 camera.

One of the advantages of the 174 is the fast frame rate, this is likely to help get a better image in poorer seeing conditions. Those times when I only have a few white light frames that I can stack, hopefully I'll have four times as many next time. All those captures I dumped because clouds came over before I got enough frames, many are keepers now. Those images of course are not going to be better than an image taken with a slower camera in great seeing for your full capture time. Slower frame rate cameras will carry on taking great pics.

Also a faster camera could mean getting more tiles done of a mosaic, again you are not going to see this comparing best versus best pics.

Or with my untracked imaging, I should now get larger tiles because I can get my usual 1700 frames in less time with less drift, and the chip is bigger to boot, and the aspect ratio is kinder to drift than my current camera. Again, this won't show up in a best versus best image. Maybe I will start using an 80mm instead of 60mm scope for untracked imaging.

I was in early with the Quark too. But I had already evaluated h-alpha options and I knew a good enough image when I saw one taken with the Quark, and the price was taken into account. I have seen good enough solar images taken with the 174 chip. This chip has already been on the radar having been used in other brands. ZWO has a proven track record. I imagine anyone who has got the ZWO at a bargain price will be able to sell it on with little or no loss if they decide not to keep it.

I am just saying, these things are not always as unconsidered as they may look     If the camera was £899 I am sure there would not have been as much interest so soon...

[Astroboffin]

I totally agree, but to get the best out of this new camera, as I have said before, will require a damn good PC with SSD hard drive, which is not something that everyone considers when purchasing the camera, as a ex computer technician, I understand what is required to get the best possible from these cameras, and not every body does, and people can buy them expecting great thinks only to be a little disappointed, not by the camera, but the lack of computing hardware needed, to reproduce the what the spec says.

I just think sometimes this should be explained a bit more by the manufacturers when advertising these cameras, so some of the less computer minded people understand what they need, I am not knocking anybody, good luck to all of you and clear skies for your first tests with these cameras.

Like I say if anybody has an 120mc-s they want to part with then let me know.

AB

[JamesF]

Looks like those who haven't bought yet will now have to wait a couple of weeks as they appears to have stopped taking orders for the next couple of weeks whilst they're on holiday for Chinese New Year.

James

[michael.h.f.wilkinson]

Somehow DHL has transferred mine from Amsterdam to Brussels. Given that Groningen is about as far from Belgium as you can get, this is puzzling (apart from annoying). The status hasn't changed since 2:00 AM