Trap close up

[multiweb]

Another night of great seeing in Sydney yesterday. Been playing with the Mewlon 210 and a new small video cam. ZWO ASO 120MM. Bit of stuffing around the moon at first trying to figure out drivers, spacing, the best software capture to use, video or still frames, calibration, etc... So a bit of trial and error. Lots of potential once I iron out all the "bugs".

Very small pixels at 3.75um. The field at 2.4m is about 6 arc min square.
I did try both videos in Firecapture then as an ASCOM camera in Nebulosity 3 and also tried as Video CAM with various levels of success. Haven't settled down on the best way to do this yet, although I do like the firecapture real time stacking like the old SBIG STV cameras.

I ended up having to guide with the lodestar on an OAG. Next will be the AO and try to do videos only. I had issues flat fielding and calibrating. Haven't got that one right yet. Because of the lack of vignetting my best bet will be to clean the sensor and camera window and keep it simple.

Looking forward to play with it again when weather allows. If anyone has had some success in firecapture or doing longer exposures with these type of cams please chip in and let us know. :thumbsup:

[Atmos]

Really good resolution, seeing appears like it was reasonable stable. What exposure time are you working with?

[gregbradley]

Impressive Marc. Orion trap double star splits are impossibly difficult.

Greg.

[RB]

Nicely captured Marc.

:cheers:

[Placidus]

Ripper resolution.

Especially with that scope, I'd love to see you using a planetary imaging approach - going to a high frame rate underexposed video and then using RegiStax or the like to select and stack the best 10% of frames. Result should be even more awesome.

Best,
Mike

[Shiraz]

nice work Marc. Agree with Mike, worth trying AS!2 stacking software and short exposures in Firecapture (eg 20+ fps) - you will not need to guide at all then.

[multiweb]

Thanks Colin. I did 5s exposures in Nebulosity. 103 subs. Seeing was good, quite a warm dewy night, no wind at all. Clouds backwash on and off from the east. Mozzies were fierce. Got hammered, even through the aeroguard. :sadeyes:


Thanks Greg. :thumbsup: I'll get those damn doubles. I can see them now. Still not separate but I'm working on it. ;)

Thanks Andrew. Cheers. :thumbsup:


Thanks Mike. :thumbsup: Makes sense. This video stuff is still a little foreign to me so baby steps.

Thanks Ray. :thumbsup: I did two videos and indeed it seemed a little sharper.
I have to read up on firecapture and the others and work a few things out. Might even barlow with the FFC and put the AO in the imaging train.

[Dennis]

Hi Marc

These are very nice, almost Hubblesque in terms of image quality and resolution.:thumbsup:

If you get the AO working I reckon you’ll knock the Hubble off its perch with the Mewlon 210.;)

Cheers

Dennis

[Dennis]

Hi Marc

Here is an inverted image with the Mewlon 180, ASI174MM and TeleVue x2 Powermate at an effective focal length of 4320mm at F24 unguided

I used Firecapture (FC) and this image is a blend of two AVI’s as follows:

200 frames at 300ms exposure, Gain=300, Gamma=50
50 frames at 5 secs exposure, Gain=275, Gamma=50

I think that the Default Gain setting in FC is 200, so I increased it for these images. I generally leave the Gamma at the default=50.

The final image has been heavily processed to blend the two images from the AVI’s to reveal the Trap and components A through I1 and I2.

The ASI174MM has 5.86um pixels so you should get wider separation with the ASI120MM 3.75um pixel pitch. More pixels in the gaps as it were!

Looking forward to more from the Mewlon 210!:)

Cheers

Dennis

[multiweb]

Hey Dennis, thanks heaps for that. :thumbsup: I'll have to read it again when I'm on my PC. I saw your shots in the solar section. Gee, you guys are getting a decent frame rate. I have to check my USB hub and extensions. I'm not even close to that. The DMK was heaps faster but it was firewire.

[RickS]

Very cool high res shots, Marc & Dennis!

[Dennis]

Hi Marc

I’m still exploring the frame rate with native USB3 ports throughput, as I’ve only used the ASI174MM 2 or 3 times (my ASI120MM is USB2 only).

For my Sunspot session, I saw the frame rate start at around 120fps but now that I’ve had a couple of sessions with the Moon (where I hang around the computer screen), I noticed that the frame rate starts at approx. 120 fps as the frames are buffered in memory (my Notebook has 8 Gig RAM ) then it quickly drops to between 7 and 15 fps before bursting back up to 120 fps as the “Captured” number of frames reaches the set target (say 2,000) and then it writes them to disc at 120 fps from the RAM Buffer until the “Recorded” target also reaches 2,000.

This is at the full res 1920x1200.

Cheers

Dennis

[multiweb]

Thanks Rick :thumbsup:



Wow! 120fps. I must be doing something wrong. I'm not even close to 20fps. Gonna try tonight again on the bench and check the settings. You say you buffer to RAM. I have 16GB. Does Firecapture buffers automatically then writes to HD or is it a setting? Might have to rtfm again.:question:

[strongmanmike]

So just interested Marc, if you discovered a never before recognised proplid or a new star in this image, would you keep it to yourself?...or could we expect to read 100s of posts about how you discovered this? :)

Mike

[multiweb]

You can look for them if you want I'm more interested in fixing my fps with Dennis, that seems more productive atm. :)

[Dennis]

Hi Marc

My default installation of Firecapture generates a Text File for each capture.
Here is an excerpt from a Solar AVI at full resolution of 1936x1216.

FireCapture v2.4 Settings
------------------------------------
Camera=ZWO ASI174MM
Profile=Sun

Filename=Sun_21_11_2015_084921.avi
Duration=8.409s
Frames captured=1000
ROI=1936x1216
FPS (avg.)=118
Shutter=0.064ms
Gain=120
USBTraffic=80
Gamma=50
Brightness=1
HighSpeed=off
SoftwareGain=10 (off)
Limit=1000 Frames
Sensor temperature=49.0 °C


Here is an excerpt from a Lunar AVI at full resolution of 1936x1216.

FireCapture v2.4 Settings
------------------------------------
Camera=ZWO ASI174MM

Profile=Moon
Filename=Moon_201416.avi
Duration=105.704s
Frames captured=1353
File type=AVI
ROI=1936x1216
FPS (avg.)=12
Shutter=10.00ms
Gain=220
Gamma=50
USBTraffic=80
Brightness=1
HighSpeed=on
SoftwareGain=10 (off)
Limit=3000 Frames
Sensor temperature=40.5 °C


So, the Sun was recorded at 118 fps whereas the Moon was only 12 fps and I was using the same PC and native USB3 port. Not sure if it is because each lunar frame contains more detail/data compared to a typical solar image?

Cheers

Dennis

[Atmos]

The difference appears to be that you had Highspeed on with the Moon but not the Sun. Seems counterintuitive but you never know.

[multiweb]

Thanks Dennis. I'll do some testing tonight and look for these log files. I assume the 120MM has the same somewhere. Your shutter speed on the moon was 10ms vs. 0.064ms on the sun so that would affect the frame rate?



I tried Highspeed on and off and it didn't seem to make much difference. Not sure what that actually does. Maybe a faster download through the USB line, like other CCD cameras.

[strongmanmike]

He he no worries i will....buuuut if i find something im sending out 100's of posts :P

Allways like a good b&w trap btw :thumbsup:

Goodluck with the tinkering :)

Mike

[Dennis]

I think the frame rate is set “automatically” by FC.:question:

So, if your shutter/exposure is say, 100ms, then the frame rate would be 10 fps as each frame is exposed for 1/10 second so the max you can get in 1 sec = 10 frames or 10 exposures.

Cheers

Dennis

[Dennis]

Based on this assumption, with the Moon exposed for 10ms (= 1/100 sec) I would have expected a frame rate of around 100 frames per sec but my average was a miserable 12 fps in the example above.:shrug:

Cheers

Dennis

[multiweb]

Still doing some testing. Changing ports, will try another PC this arvo. FPS seems only related to specific resolutions from early testing. I found those log files too. :) and flat fielding. It was right under my nose. What a douche. :lol: Will post results this arvo. :thumbsup:

[multiweb]

Ok, moving a bit forward with all this. Figured out a few more things including flat fielding and dark subtraction.
Found the log files and the fps on the night was pathetic. ~1 to 3 fps. No surprise I couldn't even separate those stars. There's just barely a hint of them as a line at 11'oclok from the brighter one but that's about it.

I managed to get a sustained 25fps today on the bench with res ranging from 960x960, 1024x960 and native 1280x960. I went from under 1ms exposures up to 10ms no problem, from 100ms onwards the fps quickly drops to 15 then 10fps. Also played with the RAM buffering settings. Didn't seem to make a big difference. CPU usage is 50% on the dual core, HD speed is fine, so I can only conclude the bottle neck is simply the USB2.0 connection. A faster lappy or more RAM would make jack squat difference. I did the test with a 1.5m cable straight to the notebook. Tried 3 various ports. Killed all the background processes to make sure FC was the only thing running. Same result.

So if I can get around 20fps on the night I should be ok. Just waiting for another clear night now. :)

[Dennis]

Did an indoors run today with my 3 to 4 year old Samsung Ultrabook (Intel Core i7-3517U dual-core CPU that runs at 1.9GHz, Graphics are also handled by the CPU (Intel HD 4000), 8GB of DDR3 SDRAM, 128GB solid state drive (SSD)) and a USB3 connected external WD 1TB My Passport Ultra HDD which runs at 5400rpm.

I managed to get bursts of 128fps with an average of 118fps over 3,000 frames.

The ASI174MM and WD HDD were connected to native USB3 ports on the Ultrabook.

I opened the ZWO camera app (no recording running) and it showed that it was connected to a USB3 port with a frame rate of 128fps.

Cheers

Dennis

[multiweb]

Very cool. USB 3.0 is a lot faster. Now the SSDs are much cheaper I'm considering getting one for my notebook. I checked a few gaming forums and I possibly could get a 25% gain in performance.

Found this interesting article (https://www.ptgrey.com/white-paper/id/10692)on the point grey website and also some good generic trouble shooting tips (http://support.userful.com/How_To/Setting_Up_USB_Devices)on USB.

Got out again last night. Didn't get much higher fps. Around 18fps max, 10fps full res.

Decided to use the AO later around 22:00 which was a bit of a challenge to set up between remembering which cable was which in the dark and what software to use. I ended up using PHD2 which I've never used before. The calibration and AO detection etc... was a walk in the park. You just press buttons and follow the prompt. Guiding results not so good though. Lots of latency.

Got a bright star around the trap and managed to have the lodestar lock at 0.1s on a good guide star. Corrections weren't even close to 2 per second though listening to the plate. I recall getting up to 5Hz with the native Starlight Xpress program. I captured 10s and 5s subs in 16Bit FITS on Nebulosity 3 using the ZWO-ASI ASCOM driver. That seems to work best I also tried the Microsoft WDM setup as well and that proved to hang all the time.

Then moved on to the cone nebula thinking I could try to do the tip of the xmas tree. Good luck with that. Moon glow was a bit of a nuisance. I got some stars that I think are in the field but no neb. I'll have to platesolve to see where I ended. The fov of the 120MM is so tiny it's hard to see where you land even with an "accurate" GOTO. Also tried to go to the HH. The top of the head should have fit the FOV. Couldn't find any guide star. Probably because of the sky glow.

So ordered two active USB extensions from Lindy and a SanDisk Extreme PRO 240 GB Internal Solid State Drive see if I can boost the transfer rate. It has the best reviews for write rate on Tom's hardware. The plan is to have the ASI on its own USB port. I suspect it clogs all USB traffic to the Mount Hub Pro from HitecAstro, including guiding corrections and AO, which goes through the GPUSB. So ideally it should works as follow:

Video Cam on USB2.0 port by itself.
Mount Hub Pro on another port.
If I have to use the AO I'll use ST4 from the lodestar rather than GPUSB as my new Gemini box allows for that. Never tried it as I'm still using the old way from my old box. Maybe time to move forward.

Will post new pics when I've processed them.