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On 23/09/2016 at 20:13, Allinthehead said:

Results from last night.

76 30 second subs Gain at 450 

No calibration and problems with temp control

stacked in dss, stretched, and noise reduction

sw ed80 with .85 ff

Do the stars look overexposed? 

Good results. I think the stars do look a little overexposed, perhaps through using a gain of 450. But then again, I find I am using my ASI1600 in a similar fashion to my 1100D - 3-5min subs. I've not yet ventured too far into taking many far shorter subs so you may be fine. 

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Here is an unguided image made possible by the ASI1600. M31. 229 x 30 seconds at unity and 90 x 10 second binned 2x2 each RGB for under 3 hours total. TS60ED on a StarAdventurer. Amazing what can be d

Here is my latest. Narrowband 5 mins subs for all the Ha, Oiii, Sii channels. The weak signal Oiii caused problems as the amp glow at 5 mins is proving a little tricky to be honest. End result is hard

Great image - lots of data in that Here are my stacked and post-processed subs from Friday night into Saturday morning.  All subs were 30s exposure with 135mm f2.5 Asahi Super Takumar lens at ful

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I ditched Apt for camera control because it disconnects the camera when changing settings. The cooling stops and temps rise rapidly. I downloaded SG pro and i find that great. Figured it out in minutes. 

Got 60*60 second subs on saturday night.

Gain at 380 offset at 50

Temp at -25

No Calibration frames

No filters yet

wallfinal.png

Edited by Allinthehead
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Relating to this camera - I have just received the ZWO EFW mini filter wheel to use with this camera and have tried fitting 1.25" mounted Astrodon NB filters and they fit fine, in spite of them exceeding the height limit stated in the EFW mini data.  This is very good news :)  I have notified FLO so that they can add this information to the filter wheel data.

Edited by Gina
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23 hours ago, Allinthehead said:

I ditched Apt for camera control because it disconnects the camera when changing settings. The cooling stops and temps rise rapidly. I downloaded SG pro and i find that great. Figured it out in minutes. 

Got 60*60 second subs on saturday night.
Gain at 380 offset at 50
Temp at -25
No Calibration frames
No filters yet

When I have a bit more time I will take a closer look at SG Pro. Looks pretty comprehensive in features.:smile:

Now, challenged by your short subs image above, I decided to have a go at IC405 in Ha last night:

148 x 2mins at -25C and using the 'Lowest read noise' preset for the camera (so gain only 300).

IC405_300mins_Neb (Custom2).jpg

People have said the amp glow is not such an issue on short subs but this stack (from DSS Live, stretched hastily in Nebulosity3) shows nasty artefacts on the right-hand side. Individual frames looked fine. Somehow feel longer subs would have made the artefacts easier to remove and actually given better SNR. Admittedly IC405 started very low. When I next have an opportunity I'll try and do a comparison under better conditions.

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I thought one of the advantages of using a camera that was cooled was that I would not have to do any darks ... I suppose, at least, that I will not have to take them at the time, because I will be able to reproduce the temperature correctly, but it still comes as a bit of a blow ...

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Yes, a disadvantage over a CCD (or at least some of them) but yes, just takes sets of darks for the different exposures etc. and after the first calibration use a master dark as appropriate.  I think the bigger sensor at lower price plus the very low read noise well makes up for having to take a set of master darks.

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I've also downloaded SGPro to use with the 1600. Looks very good so far.

I purchased the Mosaic and Framing wizard toowhich is only an extra £30. This looks excellent.

Also just wondering if people are dithering when doing higher gain narrowband imaging. I read a couple of CN posts that recommended this.

I'm still amazed such short exposures are possible for narrowband with the camera :icon_biggrin:

Andy.

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19 hours ago, Demonperformer said:

I thought one of the advantages of using a camera that was cooled was that I would not have to do any darks ...

Even cooled need darks as cooling doesn't cancel dark current or presence of warm/hot pixles, uneven columns/rows and so on depending on sensor vendor and design. Cooled cameras use set-point cooling so you can take darks easily as the temperature is set to a fixed value.

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35 minutes ago, Allinthehead said:

Do you know if SGP supports dithering without guiding?

Looking at the below statements from the help text SGP uses the auto guider for dithering.

"Dither between frames with your choice of three auto guiders (PHD, Astroart and MetaGuide)"

"As of now, SGPro does not have its own auto guider so when we say “supports” we mean that we are able to request that the external autoguider perform a dither operation between frames"

Andy.

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Hi

My ASI1600MM-C arrived and I got a clear night on Thursday so managed to use it in anger. I lost most of the evening to non-camera related issues so only managed to take usable images of M45. With 30s subs, I captured 15 mins of L and 5 mins each of RGB at a 300 gain. This was my first attempt at LRGB imaging and I have a few questions - not all camera related.

- I set cooling to take 2 mins. Is this too fast? Will the speed of cooling need to change depending on ambient temperature/humidity?

- I'm using SGPro on trial as previously I was using BackyardEOS. In its frame/focus module, is it possible to reduce exposure below 1 second? 1 second is fine for finding focus but I find it far too slow for aligning my mount (an alt/az goto). I know the camera can achieve fairly high fps and it's sensitive enough that short exposures on bright alignment stars are not a problem.

- I was taking subs in a ratio of 3/1/1/1 (all bin1). What ratio would you recommend between L and RGB? Should I be binning RGB?

So far (and this is from limited use) I have to say this camera is a real step up from my DSLR.

large.M45_20160929_v2.jpg

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On 28/09/2016 at 12:22, Gina said:

Relating to this camera - I have just received the ZWO EFW mini filter wheel to use with this camera and have tried fitting 1.25" mounted Astrodon NB filters and they fit fine, in spite of them exceeding the height limit stated in the EFW mini data.  This is very good news :)  I have notified FLO so that they can add this information to the filter wheel data.

Thanks Gina.
I'm close to buying and got some astrodons at a nice price so thats good news.

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Here is an unguided image made possible by the ASI1600. M31. 229 x 30 seconds at unity and 90 x 10 second binned 2x2 each RGB for under 3 hours total. TS60ED on a StarAdventurer. Amazing what can be done in quite a short time (ie 1 uk night) with this camera and a setup to take advantage of it.

 

 

Andromeda_LRGB.jpg

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2 minutes ago, MattJenko said:

Here is an unguided image made possible by the ASI1600. M31. 229 x 30 seconds at unity and 90 x 10 second binned 2x2 each RGB for under 3 hours total. TS60ED on a StarAdventurer. Amazing what can be done in quite a short time (ie 1 uk night) with this camera and a setup to take advantage of it.

 

 

Andromeda_LRGB.jpg

Wow, now thats nice...

Alan

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Great image, Matt.

Why did you bin the rgb? I know there's an advantage when using ccd, but afaik not with cmos.

Just wondering while admiring your image. 

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3 hours ago, wimvb said:

Why did you bin the rgb? I know there's an advantage when using ccd, but afaik not with cmos.

I thought it was standard practice with a mono camera rather than a CCD/CMOS thing. :icon_scratch:

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I'm doing a bit of initial testing with my 1600. I just did a test dark frame of 300s at -20c and unity gain.

I've done a basic stretch on the image in SGP. Below is a screenshot showing the top left of the image at 100%.

Is this about what would be expected in terms of the number of hot pixels?

Capture.JPG

Andy.

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First try in anger , trying to get to grips with new equipment , this is a dirty 10 X 60 sec subs unguided  and stretched in Gimp, may have to bite the bullet and purchase a decent image manipulation program , but I know now everything is working . 

ED80, zwo1600 AZ-EQ6

test1.JPG

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Thanks :)

The idea behind binning isn't sensor specific. The aim is to trade off resolution for sensitivity, so adding the 2x2 pixel values together. RGB doesn't need resolution at all, nor really even need to be very noise free as long as there is some signal there as I can be extremely aggressive in processing. This simply means I can reduce the exposure time by a lot and get plenty of subs quickly for this extreme processing, which gets a lovely detail Lum added once crunched together in a kind of modern photo-magical alchemy.

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Here's my second attempt at LRGB using the ASI1600MM-C on the Esprit 80ED, this time on M33 Pinwheel galaxy. Using 300 gain and at -20C, I captured 81 L, 34 R, 35 G and 33 B with 30s exposures (so about 91.5 minutes total imaging time).

The camera is definitely easy to use but I still need much more practice on processing, particularly masking.

large.M33_20161002_v1.jpg

Edited by Filroden
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Hi

What offset value is everyone using with this camera?

I've currently got mine set to 10 as I'd seen it suggested somewhere.

Also, are you leaving your camera attached to scope in the observatory? I've been advised it should be fine as I my observatory doesn't get damp - but I'm a bit wary :-)

David

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On 02/10/2016 at 13:38, MattJenko said:

Here is an unguided image made possible by the ASI1600. M31. 229 x 30 seconds at unity and 90 x 10 second binned 2x2 each RGB for under 3 hours total. TS60ED on a StarAdventurer. Amazing what can be done in quite a short time (ie 1 uk night) with this camera and a setup to take advantage of it.

Cracking image of M31 and good to know about the technique of binning RGB too.

Andy.

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