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INDI Library v1.8.4 Released

Minor bugfix release with some highlights:

Re:Re:QHY5iii-224C settings please

1 week 5 days ago
khobar
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Re:Re:QHY5iii-224C settings please #51016
Hello!

Does anyone have any suggestions for settings to use an uncooled planetary camera (QHY5iii-224C) for DSO just so I can put a check-mark in my experiment book? It uses the IMX224 chip, small, I know, but M97 image scale is perfect with this cam and my 80mm APO (similar to my much larger and heavier C8 DSLR combo). The cam can go to 1200seconds, but that's nuts. I experimented last night with 30s unguided, and while I got the target, it looks like crap. Since I forgot to remove the imaging LP filter, I'm thinking that likely partly explains the poor result. Not changing anything from default in Ekos might explain some more.

I get another chance Monday night according to the weather report. So, any suggestions on settings?

Thanks!

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1 week 4 days ago
TallFurryMan
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Re:Re:QHY5iii-224C settings please #51023
Would you care to elaborate on the "look like crap" part? With this camera, and focal length around 480mm, you get 1.6"/pixel. This requires a good guiding setup. The LP filter should only require you to increase by 150% or so your exposure duration. Also don't forget that CMOS cameras will push your histogram far off the left because of the low noise, and that you need to stack frames to get results. To get an overview of what numbers are for this type of hardware, look for the presentation from Dr. Glover on YouTube (
).

-Eric

HEQ5-Pro - Atik 314E - Orion ED80T - DMK21 on Orion 50mm
DIY 3D-printed Moonlite and FWheel RGB/LPR
KStars and indiserver on two Atom 1.6GHz 1GB RAM Linux, VPN remote access

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1 week 4 days ago 1 week 4 days ago by khobar.
khobar
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Re:Re:QHY5iii-224C settings please #51044
Hi Eric!

What I mean by crappy - see attached. That is a single frame and a DSS stack with adjustments applied for clarity. Noisy, lack of detail, and amp glow upper right and middle left? I shot 135 frames, 30s unguided, along with darks, flats, and bias, and stacked them both in DSS and Astro Pixel Processor. DSS actually gave the better result but it's still crappy. Now, it could be the debayering went awry or my DSS settings are just wrong - I've not processed images from this type of cam before and this was my first go.

Also, thank you for the most excellent presentation video - I've watched it before. Excellent and meaningful answer to the popular question of how long should the exposures be and why.

It's supposed to be clear here tonight so with luck I'll be able to guide.
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1 week 3 days ago
khobar
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Re:Re:QHY5iii-224C settings please #51112
Last night I was able to get 2minute subs, guided. The end result is no improvement, though. Resulting image still effectively gray scale even though I see color pixels.

I also noticed something that seemed really strange. Normally, when shooting with my DSLR, it takes an image, Ekos then delays the next image until dithering is complete. Last night with the QHY, it just started the next image immediately. This resulted in many, many bad frames. The obvious "solution" is to put in a delay larger than the total dithering and settling time, but doesn't seem right. Is it, do you know?

I'm going to keep mucking about with these images. Maybe something will come to light.

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1 week 3 days ago
TallFurryMan
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Re:Re:QHY5iii-224C settings please #51125
I'm curious about the gain level you used. Also, the subtle stripes oriented diagonally remind me of a reflection in the tube, but I'm certainly wrong. In any case, amp glow is not surprising with this camerav you need to choose your exposure, and stack til death :) Are you using the internal guider?

-Eric

HEQ5-Pro - Atik 314E - Orion ED80T - DMK21 on Orion 50mm
DIY 3D-printed Moonlite and FWheel RGB/LPR
KStars and indiserver on two Atom 1.6GHz 1GB RAM Linux, VPN remote access

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1 week 2 days ago
khobar
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Re:Re:QHY5iii-224C settings please #51135
Yes, internal guider. Tonight I lowered the settling time to 15 seconds and added a delay of 30 seconds between shots. We'll see if that does better than before.

I found where I can set the Bayer matrix in the driver.

I removed the LP filter to help with light.

The gain was purely a guess. Tonight I'm using "10" and see the histogram being very roughly 1/3 from the left. Promising.

The FITS preview that comes up after each sub looks good with little amp glow tonight. Promising, too.

Autostakkert 3 shows the FITS subs looking pretty good.

When I bring in/look at individual subs in DSS they look pretty smooth. Once stacked, however, ugh....

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1 week 1 day ago
khobar
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Re:Re:QHY5iii-224C settings please #51191
I tried M97 again last night without much success. I then turned attention to M51 and got a different result:

Initial (no flats/bias/darks):


I then changed the Bayer matrix to GBRG and got this from the same data though with flats/bias/darks added):


Someone suggested this was walking noise (though dither was enabled) or USB noise. Any thoughts?

Thanks.
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1 week 1 day ago
khobar
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Re:Re:QHY5iii-224C settings please #51196
Reshot the darks and bias files and got this:
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6 days 6 hours ago
TallFurryMan
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Re:Re:QHY5iii-224C settings please #51324
I assume you looked at www.qhyccd.com/index.php?m=content&c=ind...show&catid=30&id=133 too? The advice here is to raise the gain as much as possible, and decrease the exposure under 5 seconds. And stack thousands of frames.

There should be less amp-glow than what you found, maybe there is a setting to enable? It seems offset is also important.

I only ever used ccd chips. It's been a few months I've looked for a new camera, and deciding whether to remain with ccd or move to cmos is challenging...

-Eric

HEQ5-Pro - Atik 314E - Orion ED80T - DMK21 on Orion 50mm
DIY 3D-printed Moonlite and FWheel RGB/LPR
KStars and indiserver on two Atom 1.6GHz 1GB RAM Linux, VPN remote access

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5 days 8 hours ago
TallFurryMan
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Re:Re:QHY5iii-224C settings please #51351
I saw @jmfdiver on Twitter finding out there was light infiltration in the optical tube at the focuser level with her 183mc. That's a very good point I think.

-Eric

HEQ5-Pro - Atik 314E - Orion ED80T - DMK21 on Orion 50mm
DIY 3D-printed Moonlite and FWheel RGB/LPR
KStars and indiserver on two Atom 1.6GHz 1GB RAM Linux, VPN remote access

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