SharpCap Forums

Altair Astro 183M V2 and 80mm EDT Huion Flat Screen, Dell Latitude 6110.

The sensor analysis seems to be in three phases. Light, Dark and then Light again. This last process was running for nearly four hours. My previous run indicated that the light source was maybe too bright and it was reaching the lowest exposure setting of 1.9ms. This was after around 2,400 frames and an hour. By adding a T Shirt to the end of the scope reduced the list output and I restarted the process. Again on the third phase and four thousand frames later the minimum of 5.7ms was being assessed and it seemed to be hung just taking more and more frames. I did notice it was only using one memory buffer out of twenty seven and I'm wondering if yesterdays release would fix this?

I'm not actually on my PC at the moment but I will take a look at the logs.

Regards

Chris

I had the same here, right down to the t-shirt.

I got through the first two parts, then it said it was too bright, and refused to go further. I started over with a 2nd layer of tshirt, and it never finished.

This was 3.1.5186. zwo asi-1600mc-cooled.

Thank you for the log file - that's most helpful.

What is strange about it is that it gets to the end of the dark measurement and tries to turn up the exposure to get a brighter image and for some reason gets stuck with an exposure of 250ms. I will have to try to work out what is going on there as it looks like the core of the problem.

Robin

Ah, OK, the 250ms repeated over and over is the code waiting for you to uncover the sensor so it can continue with the final set of measurements. It looks like at one point the sensor was uncovered as the brightness went up and the exposure dropped, but then it went back up to 250ms again. I think you may then have pressed 'proceed' with the sensor still covered, which led to SharpCap trying very high exposure values to get a decent brightness level and it all takes forever.

In digging into this I have found one case where the code could really get stuck in a loop trying the wrong exposure and that will be fixed in the next version. I will also make it impossible to proceed when asked to uncover the sensor if the exposure is at the 250ms maximum (ie it will not let you proceed if you haven't uncovered the sensor). Finally, some sort of bail out if the exposure goes above 10s is probably in order too.

cheers,

Robin

Hi Robin

I downloaded the latest build and one other thing I chose a smaller area at the beginning of the process and guess what it worked, all done in about
forty five minutes. I have a question : Is it worth doing this for each of my NarrowBand filters?


Regards

Chris

www.digitalastroimager.com

No, the analysis measures the characteristics of the sensor on the camera which are independent of the filter (or telescope/barlow/reducer for that matter) that you connect it to.

Using a narrowband filter will change the apparent brightness of the sky background (make it much darker) - the smart histogram feature will automatically take this into account as it measures the sky background brightness in order to perform its calculations. You should redo that sky background brightness measurement for each filter - at least until you get a good idea of the typical brightnesses you see for each one, anyway.

cheers,

Robin

RE the area size, I keep looking from somewhere in the UI where it tells you the size (X&Y) you have selected.

Is it there and I just don't see it?

If not, asking the user to "pick at least 100 pixels per side" isn't very clear (well it's clear, it's just not super obvious and easy to execute on),

dts350z wrote: Wed May 23, 2018 12:07 am RE the area size, I keep looking from somewhere in the UI where it tells you the size (X&Y) you have selected.

Is it there and I just don't see it?

If not, asking the user to "pick at least 100 pixels per side" isn't very clear (well it's clear, it's just not super obvious and easy to execute on),

Good point! Perhaps that should be somewhere!

Robin

Yeah or you could have the boundary turn green when it's a good size.

Red = too small
Yellow = too big

I guess might be less than helpful through a red filter or night mode though.