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.
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.
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.
Really good resolution, seeing appears like it was reasonable stable. What exposure time are you working with?
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.
Quote:
Originally Posted by gregbradley
Impressive Marc. Orion trap double star splits are impossibly difficult.
Greg.
Thanks Greg. I'll get those damn doubles. I can see them now. Still not separate but I'm working on it.
Quote:
Originally Posted by RB
Nicely captured Marc.
Thanks Andrew. Cheers.
Quote:
Originally Posted by 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
Thanks Mike. Makes sense. This video stuff is still a little foreign to me so baby steps.
Quote:
Originally Posted by 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.
Thanks Ray. 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.
>snip
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.
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!
Hey Dennis, thanks heaps for that. 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.
Hey Dennis, thanks heaps for that. 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.
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.
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
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.
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?
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
You can look for them if you want I'm more interested in fixing my fps with Dennis, that seems more productive atm.
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?
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?
Quote:
Originally Posted by Atmos
The difference appears to be that you had Highspeed on with the Moon but not the Sun. Seems counterintuitive but you never know.
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.
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.
I think the frame rate is set “automatically” by FC.
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.
