Let us discuss the possibilities of imaging under bortle 8/9.
What are the techniques to be used to collect data from the Reflection nebulae and the other broad band targets?
I wish all experienced will give suggestion and tips for people who share urban sky like me.
Regards,
Ajith Everester
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
I think the only really useful thing you can do is increase your integration time, if you really are determined to go after broadband targets
I wouldn't use broadband light pollution filters, even if I was desperate and in B9
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Yes, as above stated, youll need more imaging time with shorter exposures but even after that you cant get the result you ll be satisfied of.
Im living in B8/9 zone, so I'd need x10 times more exposure time for my latest image as I did in B4 zone but even though the results wouldnt be good for my taste.
So maybe its worth to pack the luggage and drive to the darker sky,
becouse otherwirse the stacking programm have no chance to differentiate backgroud with eg 150 DU and the intensity of broadband object with the same value of its dimmer regions.
NB would be ok but: light pollution will cause very strong gradients in your images so prepare for the fight ))
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Usually I can get a reasonable result, but I find the process quite frustrating when computer processing time exceeds imaging time. Still, after doing a lot of narrowband imaging of emission nebula, which is easy even in Bortle 8/9, I find most broadband target much more interesting. To improve my broadband images: - choose a target high in the sky
- I block off streetlights, by putting up a screen in the garden, to decrease direct light onto the telescope.
- I use Siril for processing the data, and usually get better results doing background extraction per frame, instead of doing it once after stacking
- I use ASTAP beforehand to automatically select and discard the images with too much background noise
- and more imaging time, more is always better
- reduce exposure time of the individual frames helps, I started out with 30 seconds, went up to 120s when I got a better mount and camera, but should try to reduce this next time.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
I live in Chicago under Bortle 8/9 skies and do wide-field OSC imaging using dual narrow band filters. This can work reasonably well but you need to mind individual exposure and overall integration time depending on the filter used. In general, I find that I need to collect at least 10-15 hr of data for most emission nebulae to get reasonable images. I have an Ha/Oiii filter (Optolong L-extreme) and acquiring a companion Oiii/Sii filter as well. Ultimately, I plan to move to using a mono camera (e.g. ASI2600MM Pro) with narrowband filters. Others have been quite successful using this approach to mange light pollution. Another option is to due remote imaging under dark skies. This can get expensive and I would miss the experience of imaging myself which I very much enjoy. Check out my OSC images thus far: https://www.astrobin.com/users/jarvimf12020/. Hope this helps.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Ajith Everester:
Let us discuss the possibilities of imaging under bortle 8/9.
What are the techniques to be used to collect data from the Reflection nebulae and the other broad band targets?
I wish all experienced will give suggestion and tips for people who share urban sky like me.
Regards,
Ajith Everester Are you sure you want to get into this hobby? 😅 Unless you‘re investing in good narrowband don‘t expect anything major. And even with narrowband its gonna be limiting.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Stefan Pfleger:
Ajith Everester:
Let us discuss the possibilities of imaging under bortle 8/9.
What are the techniques to be used to collect data from the Reflection nebulae and the other broad band targets?
I wish all experienced will give suggestion and tips for people who share urban sky like me.
Regards,
Ajith Everester
Are you sure you want to get into this hobby? 😅
Unless you‘re investing in good narrowband don‘t expect anything major. And even with narrowband its gonna be limiting. Already in the hobby for past 8 years. Own a small observatory at my rooftop. 😃
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
I live in B6 - a suburb north of Milwaukee. I’ll tell you that quality broadband will be a frustrating exercise. Aside from needing long integration times, you will also need perfect flats and good processing skills to manage complex gradients. Even so, your results are likely to be disappointing because there is so much working against you - though of course that depends on your expectations. I and those I know that image here generally restrict ourselves to narrowband, usually with mono, and travel to dark sky sites to the north when we want to do broadband.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
It's a challenge, but in a sense it can be extremely rewarding to be able to get good images from a terrible, terrible observation spot! A couple of thoughts: Obviously you'll have a much easier time imaging with narrowband filters, the narrower the better (3nm might be worthwhile). This has the advantage of making a lot more of your subs usable, as it reduces considerably the issues described below. If you want to stick to visible spectrum, filters can be nice but they only help so far (the difference, at the end of the day, is not that dramatic). The real challenges are going to be: - Integration time :
- You're probably looking at 20-30 hours of light to get something good. I've done some project with 40-60 hours, that don't look anything as good as what other people get with less than 10 hours of integration.
- Even with a ton of integration time, the results are not going to look great without some good processing
- You'll realise you're throwing out a large part of all the subs you're shooting (see below)
- Light Pollution Gradients :
- Imaging for a lot of nights to get enough hours of light means that you'll be shooting at the same target from a lot of different angles (high in the sky, closer to the horizon).
- You'll want to take care of the gradients individually rather than putting together all of your subs in one big integration. This can be easier or harder depending on the software you're using to stack.
- I've had situations where integrating each night separately was good, but others where splitting images by where the object was in the sky (e.g. High vs lower down) and stacking multiple nights at the same angles together actually had better results
- Unfortunately, the gradients are not constant in the city, and they might change quite a bit depending on the activity of the city (e.g. on friday/saturday nights vs rest of the week)
- You'll have a lot of bad images among your subs, make sure you check some quality measure to identify "really bad" images that will hamper your stack more than help.
- When you shoot lower on the horizon, the type of street-lights (and building lights) in your city will start to have importance, especially if they're different in different areas in the city. That might mean getting images that are unusable as soon as the object starts dipping below a certain level.
- Processing time and space :
- With big light pollution, you'll end up having to do relatively short integrations (max 1-2 minutes), which means A LOT of images to integrate. This means a lot of processing time, and when you make an error it costs a lot of time
- Any project will destroy your HDD space very quickly
- Splitting your stacking into multiple sessions can help a lot (see comment above about grouping by gradient vs grouping by day)
- As a rule of thumb, if you're stacking at least 20-30 images per session, it's better to make multiple stacks than a single big one. It makes almost no difference in quality stacking 20x sub-stacks of 20 images vs stacking a single stack with 400x images, but it is much much faster to do 20x sub-stacks than a single uber-stack.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
I live and shoot from bortle 6 - Boston area. I have been in this hobby for less than one year; but something I had to quickly understand is that shooting dark nebulae and, in most cases, reflection nebulae is going to lead to frustrations and poor results (even for my low standards). Bright galaxies, star clusters and narrowband targets (yes, especially the latter), will be much better.
But in the end, it is all a matter of what your goal is, isn't it?
Personally, my goal is not to create images which are better, or more easily acquired, or more easily processed than others… That just won't happen. My goal is to feel over and over again the satisfaction of "seeing" things which I didn't believe it was possible to even glimpse at from my backyard.
So, I am just learning to focus on targets where the pain of acquisition and processing is less than the pleasure of looking at the result - and to stay away from those ones which I know it's just too painful to deal with (similarly to how I don't shoot subjects which are behind the trees…). I myself learn something new each time I go through processing of a new target; and learning is probably the best reward I can look for, in the end.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
I'm living in a B6-7 countryside, usually more 7 than 6, and I have the same philosophy then [url=astrobin-username astrobin-premium-member=https://www.astrobin.com/users/Rostokko/]Rostokko[/url]. I'm not resigning myself to only photography the moon. Getting a (bad) A39 with such this sky asks more time on the computer than outside with the telescope, but it's a really satsfying challenge when you see it on your screen !
Something like L-Enhance filter or so can also make things a lot better.
Good luck, and all my best regards
Eric
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
hi
welcome to bad skies
im in SQM 16.84 bad bad , my recommendations
narrowband filter ( 3nm) , imaging over 40 degree , good camera and OTA , and more more data a least 60db SNR
and the most important thing WEATHER , with bad skies that is ok ,but bad skies and bad weather ,game over
because with need more data , that mean more imaging time
and hight skills processing imaging
CS, Brian
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Also, shoot a narrow window higher in the sky. Don’t try to get a whole night on the target. The less atmosphere the better  Usually split the night into 2 or even 3 targets. Leave the lower areas of the sky for shooting stars only.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Full Moon Crescent - ReduxIts not impossible to make decent images in the middle of the city. However, I think broadband is simply off the table unless it is a bright object. Monochrome cameras and narrowband filters are the way to go. Never say never though! https://app.astrobin.com/i/230ligYou can still crank out banger broadband images of brighter targets if you are dedicated enough. Please not the lack of faint details in the background, in addition to the almost 80hrs of exposure time.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Never say never though!
https://app.astrobin.com/i/230lig
You can still crank out banger broadband images of brighter targets if you are dedicated enough. Please not the lack of faint details in the background, in addition to the almost 80hrs of exposure time. And the massive 305mm aperture. You need a lot of photons for this to get to good enough SNR, and you can do that through aperture, imaging time or (ideally) both.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Arun H:
Never say never though!
https://app.astrobin.com/i/230lig
You can still crank out banger broadband images of brighter targets if you are dedicated enough. Please not the lack of faint details in the background, in addition to the almost 80hrs of exposure time.
And the massive 305mm aperture. You need a lot of photons for this to get to good enough SNR, and you can do that through aperture, imaging time or (ideally) both. 80hrs for that…coulda been done in a single night b3 or better.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
“My goal is to feel over and over again the satisfaction of "seeing" things which I didn't believe it was possible to even glimpse at from my backyard.“
From a Bortle 7 suburban backyard location over the past 4 years I must agree with @Rostokko that this is what motivates me to keep imaging and exploring this hobby. I have been happy to shoot mostly narrowband OSC with dual narrowband filters and capture some broadband targets that are bright, well positioned, and occasionally surprise me in the acceptable quality of the result. Even when the result might be frustrating it still opens the door to further understand an amazing target, reinforce my excitement, and add to my humility. For me this is a great return on my investment of time and $ .
While I have used light pollution filters such as the L-PRO, I have been pleasantly surprised on occasion to get more color and better definition with longer total integration and no filters, taking advantage of some of the light pollution reduction tools available in APP & PS. I am content to stay with OSC at this time, even though a good case can be made to embrace mono imaging. I find it satisfying to try to get the best result I can with my available equipment, and have been fortunate to be able to aquire several telescopes with a range of FOVs which also helps to keep things interesting.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Stefan Pfleger:
80hrs for that…coulda been done in a single night b3 or better. 100%. People who haven't attempted it underestimate the absolutely MASSIVE negative effect light pollution has on broad band imaging. As I said earlier, I gave up because I never could get a quality image. Now I do narrowband exclusively and I am in B6. B8/9 will be much worse.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Arun H:
Stefan Pfleger:
80hrs for that…coulda been done in a single night b3 or better.
100%.
People who haven't attempted it underestimate the absolutely MASSIVE negative effect light pollution has on broad band imaging. As I said earlier, I gave up because I never could get a quality image. Now I do narrowband exclusively and I am in B6. B8/9 will be much worse. I‘m also around B6…actually even B5 according to LP-map but high doubts about that lol! I also only shoot narrowband from home. Broadband isn‘t worth the time and effort. If I really want to shoot something in broadband i‘ll travel to a dark site. One or two nights is already better than anything i get from home.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Jim Case:
While I have used light pollution filters such as the L-PRO, I have been pleasantly surprised on occasion to get more color and better definition with longer total integration and no filters totally agree; this is why I was saying, I would never use light pollution filters they ruin the colors IMO
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Stefan Pfleger:
Arun H:
Stefan Pfleger:
80hrs for that…coulda been done in a single night b3 or better.
100%.
People who haven't attempted it underestimate the absolutely MASSIVE negative effect light pollution has on broad band imaging. As I said earlier, I gave up because I never could get a quality image. Now I do narrowband exclusively and I am in B6. B8/9 will be much worse.
I‘m also around B6…actually even B5 according to LP-map but high doubts about that lol!
I also only shoot narrowband from home. Broadband isn‘t worth the time and effort. If I really want to shoot something in broadband i‘ll travel to a dark site. One or two nights is already better than anything i get from home. So i will carry my EQ6R and C9.25/ ED102 with ASI 294MC camera.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Arun H:
Stefan Pfleger:
80hrs for that…coulda been done in a single night b3 or better.
100%.
People who haven't attempted it underestimate the absolutely MASSIVE negative effect light pollution has on broad band imaging. As I said earlier, I gave up because I never could get a quality image. Now I do narrowband exclusively and I am in B6. B8/9 will be much worse. I have tried upto 40 hrs and gave up. Wanted to know if someone has some better ideas to reignite the idea.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Stefan Pfleger:
Arun H:
Stefan Pfleger:
80hrs for that…coulda been done in a single night b3 or better.
100%.
People who haven't attempted it underestimate the absolutely MASSIVE negative effect light pollution has on broad band imaging. As I said earlier, I gave up because I never could get a quality image. Now I do narrowband exclusively and I am in B6. B8/9 will be much worse.
I‘m also around B6…actually even B5 according to LP-map but high doubts about that lol!
I also only shoot narrowband from home. Broadband isn‘t worth the time and effort. If I really want to shoot something in broadband i‘ll travel to a dark site. One or two nights is already better than anything i get from home. If I were close to that scale I could have tried a lot of targets. It is high time for you to start.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Jim Case:
While I have used light pollution filters such as the L-PRO, I have been pleasantly surprised on occasion to get more color and better definition with longer total integration and no filters
totally agree; this is why I was saying, I would never use light pollution filters
they ruin the colors IMO
I always get a weird looking reflection of dark ring in my broadband filter flats. All chroma and heavily suffering from the flats. Thinking of getting a Alnitak Flatman to if that works. Read few articles about the Reflection from the skywatchercoma corrector. So TS optics coma corrector is also in bucket list.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
Huib Wouters:
Usually I can get a reasonable result, but I find the process quite frustrating when computer processing time exceeds imaging time. Still, after doing a lot of narrowband imaging of emission nebula, which is easy even in Bortle 8/9, I find most broadband target much more interesting.
To improve my broadband images:
- choose a target high in the sky
- I block off streetlights, by putting up a screen in the garden, to decrease direct light onto the telescope.
- I use Siril for processing the data, and usually get better results doing background extraction per frame, instead of doing it once after stacking
- I use ASTAP beforehand to automatically select and discard the images with too much background noise
- and more imaging time, more is always better
- reduce exposure time of the individual frames helps, I started out with 30 seconds, went up to 120s when I got a better mount and camera, but should try to reduce this next time.
That's an interesting comment about applying background extraction to the subs rather than the stacked image. I too have found that to be a very effective approach and use it a lot. The Siril script makes it very easy to do. I just need to dive into the script at some point and make a version that does drizzle too.
|
You cannot like this item. Reason: "ANONYMOUS".
You cannot remove your like from this item.
Editing a post is only allowed within 24 hours after creating it.
You cannot Like this post because the topic is closed.
Copy the URL below to share a direct link to this post.
This post cannot be edited using the classic forums editor.
To edit this post, please enable the "New forums experience" in your settings.
