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Long story short, I tried to image the Heart & Soul nebulae the other night and completely failed. I know I was on target due to the ASIAir annotations but after stacking 15x 5 min exposures (Lights only), there is just nothing there. Can anyone advise as to what might have gone wrong?

Canon 5D Mk IV, 200mm, f6.3, ISO 500, 300 sec

IMG_2800.PNG

22-01-13-IC180 No calib.tif

Edited by CraigD1986
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9 minutes ago, CraigD1986 said:

Long story short, I tried to image the Heart & Soul nebulae the other night and completely failed. I know I was on target due to the ASIAir annotations but after stacking 15x 5 min exposures (Lights only), there is just nothing there. Can anyone advise as to what might have gone wrong?

Canon 5D Mk IV, 200mm, f6.3, ISO 500, 300 sec

IMG_2800.PNG

22-01-13-IC180 No calib.tif 243.86 MB · 2 downloads

Is this a stretched image? Is your camera modified?

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It was the other night so the moon was quite bright.

 

Screenshot is from ASIAir Plus live so it had stacked 6 images at that point. Camera is stock.

 

I didn't expect anything amazing but after trying to stretch the tiff file (Attached above straight from DSS), I was surprised to find nothing there at all

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18 minutes ago, CraigD1986 said:

It was the other night so the moon was quite bright.

 

Screenshot is from ASIAir Plus live so it had stacked 6 images at that point. Camera is stock.

 

I didn't expect anything amazing but after trying to stretch the tiff file (Attached above straight from DSS), I was surprised to find nothing there at all

Sorry if I misunderstood this, but don't try and stretch in DSS, as they state themselves, its not a good processing tool, only good for stacking. Use other free tools such as GIMP or Siril (I've found stacking in siril is much better also, just takes a little longer), or download free trials on other software such as StarTools, APP or Pixinsight. :)

But the camera being stock is also something that will hold you back on emission nebulae such as these. Should stick to your broadband targets with stock cameras, reflection nebulae, star clusters, galaxys.

Hope this helps!

Grant

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I had the same target on Friday night, was a lovely clear night but a very bright moon. With nearly 3 hours of data i have much the same result. With much stretching and changing the colour balance aggressively i can make out the general shapes and  bright areas of the nebula. I was using a stock dslr  @ 200mm F5.6, 90second exposures. I'm pretty sure it was just because the moon was so bright. I will give it another go when the moon is in a better phase.

Edited by sebn
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As people have said moon could have washed out any signal. I haven't tried OSC but when shooting mono narrowband on the heart even 5 minute exp in S2 and o3 didn't reveal much of anything. Ha however seemed to make it appear quite drastically. So local lighting will affect when doing OSC.

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3 hours ago, Grant93 said:

Sorry if I misunderstood this, but don't try and stretch in DSS, as they state themselves, its not a good processing tool, only good for stacking. Use other free tools such as GIMP or Siril (I've found stacking in siril is much better also, just takes a little longer), or download free trials on other software such as StarTools, APP or Pixinsight. :)

But the camera being stock is also something that will hold you back on emission nebulae such as these. Should stick to your broadband targets with stock cameras, reflection nebulae, star clusters, galaxys.

Hope this helps!

Grant

Apologies, I wasn’t clear. I tried a quick stretch in Photoshop after stacking in DSS.

A appreciate all the replies and you have all put my mind at ease. I’m finding many reasons to purchase a ZWO ASI533MC Pro at the moment and this is just another.

I read that IC1831 and IC1805 were beginner friendly targets so didn’t realise. Not to worry. I’ll try again on an easier target when I get the chance.

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26 minutes ago, CraigD1986 said:

Apologies, I wasn’t clear. I tried a quick stretch in Photoshop after stacking in DSS.

A appreciate all the replies and you have all put my mind at ease. I’m finding many reasons to purchase a ZWO ASI533MC Pro at the moment and this is just another.

I read that IC1831 and IC1805 were beginner friendly targets so didn’t realise. Not to worry. I’ll try again on an easier target when I get the chance.

Just going to pass on a little advice I myself has recieved on this forum before. The only difference between an Astro dedicated camera and a modified DSLR - is cooling, which reduces noise not sensitivity to emission nebula such as the heart and soul. So why not consider modifiying your DSLR?

Edit: Especially considering your current DSLRs 30MP and massive full frame sensor, compared to the ASI533mcs 9MP and smaller-than-APS-C sized sensor

Edited by Grant93
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This image is a prime example of why flats are NOT optional if you want to be able to process an image to its full extent, you really do need to take them! There is a lot of signal in the image that just needs to be stretched out. But without flats this is unnecessarily difficult and requires some bruteforce background removal, which by itself has a tendency to wipe out faint detail (at least with my processing skills). I am sure someone could do better than this but here is my try with Siril and Photoshop:

856334064_22-01-13-IC180Nocalib-siril-PS.thumb.jpg.68e451ac4d895f57d1fb45a64b565550.jpg

i think youll agree its far from wasted and there is a lot to look at here. I tried to shield the 2 biggest/most obvious patches of nebulosity when running GradientXterminator but the process could have very well wiped other parts that would be visible with a calibrated stack.

15 minutes ago, Grant93 said:

Just going to pass on a little advice I myself has recieved on this forum before. The only difference between an Astro dedicated camera and a modified DSLR - is cooling, which reduces noise not sensitivity to emission nebula such as the heart and soul. So why not consider modifiying your DSLR?

Edit: Especially considering your current DSLRs 30MP and massive full frame sensor, compared to the ASI533mcs 9MP and smaller-than-APS-C sized sensor

The cooling part is only a part of the deal, and not the "main" reason dedicated astro cams are better than modified DSLRs. The cooler acts as a set point temperature device and allows calibration to be done properly regardless of temperature outside, which is something that is impossible with DSLRs. I dont know about the 5D MKIV but many Canon DSLRs do some weird stuff in the background to dark frames, which makes calibration difficult. My 550D always has a median ADU of 2048 in dark frames, regardless of exposure length and temperature, which means that dark frames do not work as intended. Dedicated astro cameras dont have these "hidden tricks" in them and you really do get the pixel value in raw format straight out the sensor. If you buy one of the newer backlit Sony sensor cameras you will also find that QE is a lot higher than really any DSLRs on the market. Higher QE just means that you get more out of the same time spent imaging with no drawbacks, it is just better. For example the 5D MK IV apparently has a QE of 56%, whereas the new backlit Sony sensor cameras have somewhere around 80% (for color sensors, for mono it is closer to 90%).

The full frame format of your camera could actually be called a drawback for many situations. If you want to use a telescope one day you will find that scopes that can produce a good image all the way to the edges of a full frame sensor are quite a lot more expensive than scopes that work to say APS-C size sensors. The small IMX533 sensor is an issue for some targets, true but you could work around this by just shooting smaller targets.

There is a lot more to it than just cooling, and dedicated astronomy cameras are just flat out better than similarly priced DSLRs. But they are very expensive (like everything related to cameras, so not a surprise really).

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If it's any consolation, I imaged the same targets on 3rd January. I managed to get 22 x 4min exposures at ISO800 before it got cloudy. This is with a modified EOS 1300D attached to the Samyang 135mm F2 lens, set to F2.8.

So, even from my Bortle 2 location, it needs more integration time without the Moon. ;)

1512653395_NGC1027-HeartSoulNebulas-03012022-1h45m.png.f55d02098d643d7cb2792031f4663219.png

 

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@Grant93 I wouldn’t dream of modding my 5D. It’s an expensive camera and would be useless for anything but Astro if I did.

@ONIKKINEN Is that from the TIFF file I posted at the start of this thread? If so, that’s amazing. I couldn’t get anything at all out of it so I think I need to work through some more processing tutorials. I skipped the calibration files as I dithered the lights and was previously having problems with bias and flat frames, as discussed here (Another reason for me wanting an Astro camera):

The results I get from DSS seems to be generally very odd as well. It’s as though calibration files are a hindrance a lot of the time. I’m going to reinstall and then go back through some tutorials here too

 

 

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4 minutes ago, CraigD1986 said:

@Grant93 I wouldn’t dream of modding my 5D. It’s an expensive camera and would be useless for anything but Astro if I did.

@ONIKKINEN Is that from the TIFF file I posted at the start of this thread? If so, that’s amazing. I couldn’t get anything at all out of it so I think I need to work through some more processing tutorials. I skipped the calibration files as I dithered the lights and was previously having problems with bias and flat frames, as discussed here (Another reason for me wanting an Astro camera):

The results I get from DSS seems to be generally very odd as well. It’s as though calibration files are a hindrance a lot of the time. I’m going to reinstall and then go back through some tutorials here too

 

 

Yes, from your posted TIFF! It did take a lot of stretching and saturation boosting (selectively on red in the end) to bring out anything. Without trying to fix the vignetting with flats or in my case background extraction tools you would not see anything really, since the image breaks down soon in the edges.

Its difficult to process because of the lack of flats, IMO and you would easily get a nice result if the image just had flats. Cant stretch the image very far when there is severe vignetting everywhere except the very center of the image. Quick fix you can try now, even later after the images have been taken would be to try and get every setting as they were during imaging and take flats now. Aperture and focus must be the same. Focus will be difficult but maybe focus to infinity on a terrestial target and then take the flats? They probably wont be a perfect match to the conditions you shot the lights in but much better than nothing. You can take flats by just pointing the camera to a computer monitor/TV/tablet or whatever device showing a white screen with minimum brightness. Use AV mode with the same ISO as the lights and there you go, flats taken (take maybe 30 or more, move the camera a bit between a few shots to even out dead pixels/lighting differences in your monitor).

You would be surprised how easy the image is to process once you stack it with flats and bias! And by the way, flat frames are necessary with the dedicated astro cam as well, cant really skip this calibration step if you want processable images.

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4 minutes ago, ONIKKINEN said:

Yes, from your posted TIFF! It did take a lot of stretching and saturation boosting (selectively on red in the end) to bring out anything. Without trying to fix the vignetting with flats or in my case background extraction tools you would not see anything really, since the image breaks down soon in the edges.

Its difficult to process because of the lack of flats, IMO and you would easily get a nice result if the image just had flats. Cant stretch the image very far when there is severe vignetting everywhere except the very center of the image. Quick fix you can try now, even later after the images have been taken would be to try and get every setting as they were during imaging and take flats now. Aperture and focus must be the same. Focus will be difficult but maybe focus to infinity on a terrestial target and then take the flats? They probably wont be a perfect match to the conditions you shot the lights in but much better than nothing. You can take flats by just pointing the camera to a computer monitor/TV/tablet or whatever device showing a white screen with minimum brightness. Use AV mode with the same ISO as the lights and there you go, flats taken (take maybe 30 or more, move the camera a bit between a few shots to even out dead pixels/lighting differences in your monitor).

You would be surprised how easy the image is to process once you stack it with flats and bias! And by the way, flat frames are necessary with the dedicated astro cam as well, cant really skip this calibration step if you want processable images.

Thanks. I’ll have a look when I get a minute tomorrow. My gear is still all set up so I should be able to easily take flats. Will update this thread after a second go. It’s encouraging to see that there is some data there though so thanks for having a look!

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