#341  
Old 11-06-2016, 10:30 AM
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codemonkey (Lee)
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Here's a couple of dodgy flats (pointed at my ceiling with no OTA connected) demonstrating the vignetting with 1.25" filters with the camera connected directly to the Orion Nautlius 7x1.25" EFW.

The vignetting itself isn't so bad. The filters are clearly not centered, but the main issue is that it's inconsistent. Between the two frames I rotated the filter wheel to another filter, then back to the original. This will make taking flats annoying.

Previously with the 674 and 1.25" filters I was able to take flats maybe every two weeks or so and then use them across all the filters. Now, for proper correction, I'd need to take them every time I change filters, even if I change it back to the one the flats were taken with.
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  #342  
Old 11-06-2016, 10:35 AM
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Originally Posted by glend View Post
Hm, i am still using Ascom driver V 1.0.2.5 , i did not realise ZWO had a new one. Do you know what prompted that Lee? 2.5 is only a couple of weeks old.

Anyway it probably does not impact SGP frame and focus. Here is what i have found and how i use frame and focus.
I only use 'Take One', and this works just fine, based on advice from CN beta testers, as i am usually moving the scope slightly between takes anyway, i also use it to focus with my mask. I stay away from the continuous take mode because thst's all it does, take continuiously and not download. I suspect, given the amount of time it takes for one take to download and be displayed, that the downloads are over-run by the next frame and the necessary handshake can not take place.
I like to be able to alter the frame duration as i find say a 20 sec frame is good for small framing changes on nebulas, take one is good for this sort of thing. Make sure you are not saving those frames, there is a box to tick to save, i don't think its a good idea, these files are big and the less disc space used the better.
Check your camera setting box, you maybe surprised to see that even if your running usb3 it defaults to usb2 operation. I see this all the time, it doesn't interfere with my imaging but it does lengthen downloads from the camera slightly. This may also be the reason for the Continuous frame and focus not working.
So in a nutshell: Use Take One, it works and what's the hurry anyway. I woukd still do it that way even if continuous worked. Your alternative might be to frame and focus using Sharpcap as it can be a video stream if you want, however it coukd be messy switching apps for that, especially if your checking focus on filter swaps. The beauty of parafocal filter sets, focus once - this has worked really well on my Baader filters which are parafocal.

Hope that is of some use. Ray is using SGP, lets see what he says.
Cheers Glen. I'm not sure what prompted the new driver version, I just grabbed the newest ones of everything in the hope it would work.

I've actually got the opposite problem. Continuous download on frame & focus works fine, I can do it all day with the shortest exposures the camera can do. It's the main sequencing part that doesn't work.

I've checked the camera settings thing and it's using USB3, and was by default.
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  #343  
Old 11-06-2016, 10:38 AM
glend (Glen)
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Lee give me a call to discuss, this is probably better sorted out on the phone. I will pm my mobile #.
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  #344  
Old 11-06-2016, 12:53 PM
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Shiraz (Ray)
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Quote:
Originally Posted by codemonkey View Post
Here's a couple of dodgy flats (pointed at my ceiling with no OTA connected) demonstrating the vignetting with 1.25" filters with the camera connected directly to the Orion Nautlius 7x1.25" EFW.

The vignetting itself isn't so bad. The filters are clearly not centered, but the main issue is that it's inconsistent. Between the two frames I rotated the filter wheel to another filter, then back to the original. This will make taking flats annoying.

Previously with the 674 and 1.25" filters I was able to take flats maybe every two weeks or so and then use them across all the filters. Now, for proper correction, I'd need to take them every time I change filters, even if I change it back to the one the flats were taken with.
Good point, but it might not be as bad if you test in a converging beam. I have an ancient Atik FW (probably worse than yours) and just did a few flats with my f4 system (which is really on the edge when it comes to filter alignment sensitivity). I moved off-filter and back on between the subs. At the same point in the darkest corner, the levels were:
26426
26318
26440
26063
25925
26504
26222
26758
26598
The levels in the centre of the field were much more consistent. Clearly not perfect, but I think that I can live with minor positioning errors causing a few percent error in brightness in the far corners of my images and will be sticking with the 1.25 filters for now. Not sure how much of a problem that will cause with colour, but will see.

Edit, just took the two widest apart flats and flat calibrated one with the other. The result was very flat, so should be OK.

Last edited by Shiraz; 11-06-2016 at 02:14 PM.
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  #345  
Old 11-06-2016, 02:14 PM
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Cheers Ray. What sort of light source did you use when testing that? My dodgy flat panel will have a divergent beam and I'm not sure of the impact of that on the vignetting.

I did a spot check on those two frames I posted, one in the top right corner, one in the top left. The top right varied 12.9% between the two frames, and the top left varied by 7.4%. I think the difference between the two most divergent of yours is about 3.5%

I could take multiple sets and then average them, I suppose.

In other news, SGP are looking into the issue that I described above. SharpCap has been working fine so I've been able to start capturing calibration frames. Hopefully SGP can sort it out quickly, although the forecast for the foreseeable future is cloudy anyway.
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  #346  
Old 11-06-2016, 03:04 PM
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Quote:
Originally Posted by codemonkey View Post
Cheers Ray. What sort of light source did you use when testing that? My dodgy flat panel will have a divergent beam and I'm not sure of the impact of that on the vignetting.

I did a spot check on those two frames I posted, one in the top right corner, one in the top left. The top right varied 12.9% between the two frames, and the top left varied by 7.4%. I think the difference between the two most divergent of yours is about 3.5%

I could take multiple sets and then average them, I suppose.

In other news, SGP are looking into the issue that I described above. SharpCap has been working fine so I've been able to start capturing calibration frames. Hopefully SGP can sort it out quickly, although the forecast for the foreseeable future is cloudy anyway.
Used a diffuser in front of the scope - same as your panel will give. Testing in the open under the diffuse light in a room will allow light from a very wide range of angles to affect the result - the scope will limit the range of angles that the light can come from. Suspect that will make a significance difference (of course it might not as well)

I am still using Nebulosity - I am getting only occasional bursts of clear sky and cannot bear the thought that the software will let me down.
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  #347  
Old 12-06-2016, 05:02 AM
glend (Glen)
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Jon Rista, writing in the CN beta test thread, has put up some graphic data on stacking effectiveness (SNR) with this camera.

Link here:
http://www.cloudynights.com/topic/53...9#entry7269131

And he has also suggested a Gain 75 "Sweet Spot" giving almost exactly 12 stops of dynamic range, with 2.05e-/ADU gain and 2.05e- RN, with a 8402e- FWC.

Link here, with data:

http://www.cloudynights.com/topic/53...0#entry7269537

Last edited by glend; 12-06-2016 at 08:51 AM.
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  #348  
Old 12-06-2016, 03:33 PM
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codemonkey (Lee)
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Quote:
Originally Posted by Shiraz View Post
Used a diffuser in front of the scope - same as your panel will give. Testing in the open under the diffuse light in a room will allow light from a very wide range of angles to affect the result - the scope will limit the range of angles that the light can come from. Suspect that will make a significance difference (of course it might not as well)

I am still using Nebulosity - I am getting only occasional bursts of clear sky and cannot bear the thought that the software will let me down.
Cheers Ray, that's a good point. I'll see how I go when it's actually on the scope (which is allllll the way "up there" in the paddock). I was briefly trying to confirm e-/adu for a given gain and noticed that it appears to vignette even with nothing on the camera than the black adapter that is screwed on by default (male to female M48 maybe?) and it was then that your comment fully made sense to me.

Quote:
Originally Posted by glend View Post
Jon Rista, writing in the CN beta test thread, has put up some graphic data on stacking effectiveness (SNR) with this camera.

Link here:
http://www.cloudynights.com/topic/53...9#entry7269131

And he has also suggested a Gain 75 "Sweet Spot" giving almost exactly 12 stops of dynamic range, with 2.05e-/ADU gain and 2.05e- RN, with a 8402e- FWC.

Link here, with data:

http://www.cloudynights.com/topic/53...0#entry7269537
Seems reasonable and maps pretty well to the graphs ZWO have provided.

I've captured bias (200) & darks (100 ea @ 300s and 120s) for a gain of 99 and offset 40. I'm now doing the same for gain of 74 & offset 35, although I'll probably only bother grabbing 50 darks this time, after seeing the diminishing returns from the previous set.

How annoying are those sliders in the ASCOM driver interface? I can never get gain to be exactly what I want.
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  #349  
Old 12-06-2016, 03:50 PM
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Originally Posted by codemonkey View Post
.....
How annoying are those sliders in the ASCOM driver interface? I can never get gain to be exactly what I want.
You can just type in the number you want in the box - can't you?
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  #350  
Old 12-06-2016, 04:01 PM
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You can just type in the number you want in the box - can't you?
There's no box in the ASCOM driver interface that I have...?
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  #351  
Old 12-06-2016, 05:06 PM
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Quote:
Originally Posted by glend View Post
Jon Rista, writing in the CN beta test thread, has put up some graphic data on stacking effectiveness (SNR) with this camera.

Link here:
http://www.cloudynights.com/topic/53...9#entry7269131

And he has also suggested a Gain 75 "Sweet Spot" giving almost exactly 12 stops of dynamic range, with 2.05e-/ADU gain and 2.05e- RN, with a 8402e- FWC.

Link here, with data:

http://www.cloudynights.com/topic/53...0#entry7269537
I think that Jon's analysis applies to the individual subs and will do fine for stacks as well. However, I don't think that there is actually a single sweet spot. sorry for reposting, but the attached table shows that, by choosing appropriate sub length you can get almost identical broadband stacked SNR and stacked well depth for any gain up to at least 100. It is only at the highest gains that the stacked well depth begins to drop off, but even then, a choice could be made on the basis that a bit of performance could be given up in return for the advantages of very short subs. ie, choose whatever subs length you think appropriate (for resolution, tracking, data processing load or whatever) and then select right gain to get the best possible performance - it really is a very flexible camera.
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  #352  
Old 12-06-2016, 09:02 PM
glend (Glen)
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Sam has released an ASCOM driver update, V 1.0.2.8.

He posted a notice on the CN Beta Test thread. The link is now available on the ZWO ASCOM page.
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  #353  
Old 13-06-2016, 08:06 AM
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The CN Beta Test thread has now been locked, it was getting too big (with 1800 posts), and finding things was becoming difficult. There will likely be some Beta Test Summary results put together by the major inputers to the testing.
It is likely that should be considered for this IIS thread as well at some point, but this one is only 353 posts long, big by our standards, but we still have cameras just getting into the hands of early buyers so it might have further to run here. Shiraz has the right idea in putting images into separate threads and i will be doing the same from now on. My thanks to Russell for starting this thread, which brought the camera to my attention.
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  #354  
Old 13-06-2016, 10:13 AM
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I'm not a great herd follower, so this is just MO and not those of the management, but I don't see the point in locking a thread in a "discussion" board when folk are still getting useful information from it Personally I've found it very interesting watching this develop and still seems a bit early days from my point of view, if only 3 IISers have put their hand up to blaze the trail
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  #355  
Old 13-06-2016, 11:08 AM
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Originally Posted by Camelopardalis View Post
I'm not a great herd follower, so this is just MO and not those of the management, but I don't see the point in locking a thread in a "discussion" board when folk are still getting useful information from it Personally I've found it very interesting watching this develop and still seems a bit early days from my point of view, if only 3 IISers have put their hand up to blaze the trail
I don't think i was suggesting locking the IIS thread now, or in the near term. This is a much smaller pond but in some ways were ahead of what they are actually accomplishing over there because we can actually get cameras ex-stock and our weather and skies are better.

Clearing here now, so i am heading back to NGC6188 tonight, running 300" subs over the last few clear nights, and the histogram looks much better, no need to scrape data off the floor.

Last edited by glend; 13-06-2016 at 12:58 PM.
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  #356  
Old 14-06-2016, 09:28 PM
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After over three weeks running SGP to control the ASi1600, it has now stopped working. I have just wasted two hours trying everything I can think of and it will not work properly. I had down loaded the latest version of SGP V2.5.1.15 after my last imaging session,and the new ASCOM driver V1.0.2.8, and now my system is stuffed.
Basically, frame and focus does not work anymore, just downloads and never stops. I tried using short subs in a sequence and that doesn't work either. I am out of business. My cables are exactly as they were, I have changed nothing but this software. I have rebooted the laptop, tried difference connection secquences for the various devices, checked the device manager, reinstalled stuff, and nothing worked. Well the guide camera and Metaguide worked but that's not getting me anywhere.
Anyone using these software versions successfully? Any ideas?
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  #357  
Old 14-06-2016, 10:51 PM
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I am hearing (on other forums) that there is a problem with the ZWO ASCOM .8 driver and going back to .5 works fine with the latest release of SGP (15). I will try to go back to the ASCOM .5 driver, but testing will now have to wait. What a mess.
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  #358  
Old 15-06-2016, 12:15 AM
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yes, it is turning into a bit of a mess. However, the two outfits seem to be doing their level best to get the two softwares to play together.
Although nothing like as functional as SGpro, SharpCap does the job OK, so maybe go back to manual imaging until the problems are sorted?
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  #359  
Old 15-06-2016, 02:34 AM
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Thanks Ray. I have a thread running on CN now about it, and the SGP forum and emailed Sam. I am getting indications on CN that the new release of SGP is ok only if used with the ZWo .5 driver, people seem to be holding there. Had a message from Jared at SGP saying basically ' what problem?'; and an email from Sam saying pretty much the same thing. Very odd that i have had no issues until that combination of releases ,eh? I am taking the CN forum advice and going back to the ZWO .5 driver. I might have to get out before dawn and test.
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Old 15-06-2016, 04:24 AM
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Yes i got out of bed and went back out there to test the rollback to the .5 ASCOM driver. I am satisfied that it works again, at least Frame and Focus is back to normal. I have taken a few test images which i will look at after i've had some sleep. No real conclusion yet on the SGP .15 but Sam has to sort out his driver, it is clearly a problem for some users. The random nature of the problem is very confusing, some people say the .8 driver works for them and others like me are out of action and have to roll back. Stability please.
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