Hi,
I am trying, unsuccessfully, to get acceptable linear readings for this camera when running the Sensor Analysis. Firstly, it seems like it takes forever, if at all, to produce anything when running it for RAW12. 3+ hours? Is this normal? The results, when produced, give me something not very uniform.
Note: Trying to maintain a constant natural light level for this period of time is also proving difficult. I am not sure how critical this is. If natural light is a problem what alternatives do I have?
This is the best I got for RAW12 after 6 attempts:
Any ideas how I can get a better result?
Regards Jacques
Sensor Analysis: Altair Astro HyperCam 183C Pro: Frustration.
Forum rules
One tutorial per topic please.
Please only post content that you have created in this form.
Tutorials should be either in PDF format as an attachment or written in the first post of the topic. Links to video tutorials you created are also acceptable.
One tutorial per topic please.
Please only post content that you have created in this form.
Tutorials should be either in PDF format as an attachment or written in the first post of the topic. Links to video tutorials you created are also acceptable.
- admin
- Site Admin
- Posts: 13344
- Joined: Sat Feb 11, 2017 3:52 pm
- Location: Vale of the White Horse, UK
- Contact:
Re: Sensor Analysis: Altair Astro HyperCam 183C Pro: Frustration.
Hi,
No, it should take just a few minutes to run through. I find I get best results by adjusting the light level at the point that you are being asked to select an evenly illuminated area. I aim for an exposure of roughly 1 ms at this point and then find that the rest of the procedure runs through relatively quickly.
Cheers, Robin
No, it should take just a few minutes to run through. I find I get best results by adjusting the light level at the point that you are being asked to select an evenly illuminated area. I aim for an exposure of roughly 1 ms at this point and then find that the rest of the procedure runs through relatively quickly.
Cheers, Robin
Re: Sensor Analysis: Altair Astro HyperCam 183C Pro: Frustration.
Thanks for the reply Robin,admin wrote: ↑Tue Sep 03, 2019 7:30 pm Hi,
No, it should take just a few minutes to run through. I find I get best results by adjusting the light level at the point that you are being asked to select an evenly illuminated area. I aim for an exposure of roughly 1 ms at this point and then find that the rest of the procedure runs through relatively quickly.
Cheers, Robin
The Sensor Analysis for RAW12 was very slow. I am not to sure if my settings are wrong? Should I touch the USB slider??? On the other hand, scanning the RAW8 was quicker (30 mins?) and linear, as below:
I am not too sure what I am doing wrong when trying to get the RAW12 to produce something similar to the RAW8. It is very much all-over-the-place.
Any suggestions???
Regards Jacques
- admin
- Site Admin
- Posts: 13344
- Joined: Sat Feb 11, 2017 3:52 pm
- Location: Vale of the White Horse, UK
- Contact:
Re: Sensor Analysis: Altair Astro HyperCam 183C Pro: Frustration.
Hi,
Setting the USB speed to the maximum value would likely speed up the process a bit as it increases the frame rate when you are taking short exposures. It doesn't have any significant effect once the exposure length gets above about 1/10 of a second however.
How you illuminating the sensor when you are performing the analysis? I tend to use a cheap C-thread lens with a variable aperture which allows me to focus on indoor targets and adjust the light level very easily by changing the aperture. These cost about £10 when bought from China on eBay or about twice that (typically) if bought from a local vendor for quicker delivery.
Cheers, Robin
Setting the USB speed to the maximum value would likely speed up the process a bit as it increases the frame rate when you are taking short exposures. It doesn't have any significant effect once the exposure length gets above about 1/10 of a second however.
How you illuminating the sensor when you are performing the analysis? I tend to use a cheap C-thread lens with a variable aperture which allows me to focus on indoor targets and adjust the light level very easily by changing the aperture. These cost about £10 when bought from China on eBay or about twice that (typically) if bought from a local vendor for quicker delivery.
Cheers, Robin
Re: Sensor Analysis: Altair Astro HyperCam 183C Pro: Frustration.
I think I finally cracked a better reading and curve for RAW12.
I purchased an illuminated tracing board on eBay. Adjustable. Not expensive. It gave a consistent light output. I don't think it gave out a pure white light looking at the histogram. Not sure if that matters? The result I got was as follow:
Only other adjustment was to kick up the USB to the first notch. If I ramped it to the second notch the system froze. It was still, nevertheless, slow in doing the reading. Perhaps the camera is a bit more involved than most out there?
Regards
Jaq
I purchased an illuminated tracing board on eBay. Adjustable. Not expensive. It gave a consistent light output. I don't think it gave out a pure white light looking at the histogram. Not sure if that matters? The result I got was as follow:
Only other adjustment was to kick up the USB to the first notch. If I ramped it to the second notch the system froze. It was still, nevertheless, slow in doing the reading. Perhaps the camera is a bit more involved than most out there?
Regards
Jaq
Re: Sensor Analysis: Altair Astro HyperCam 183C Pro: Frustration.
Note: I thought it a bit weird how the 'Gain' curve differed when checking in RAW8 and RAW12. Is this normal?
Jaq
Jaq
- admin
- Site Admin
- Posts: 13344
- Joined: Sat Feb 11, 2017 3:52 pm
- Location: Vale of the White Horse, UK
- Contact:
Re: Sensor Analysis: Altair Astro HyperCam 183C Pro: Frustration.
Hi,
The results that you have above look very reasonable to me.
If you put results for RAW 8 and RAW 12 side-by-side I would expect that the e/ADU, read noise and dynamic range figures would be different but that the full well depth and relative gain would be broadly similar between the two.
Cheers, Robin
The results that you have above look very reasonable to me.
If you put results for RAW 8 and RAW 12 side-by-side I would expect that the e/ADU, read noise and dynamic range figures would be different but that the full well depth and relative gain would be broadly similar between the two.
Cheers, Robin