Whats the furthest away thing you've imaged?

[John]

3 minutes ago, Macavity said:

Aside from not too difficult (DOT-like!) 3C273, the "Hubble Deep Field".
- Or rather the "faintest" and (in this case) not too attractive an image? 🥳
Most of effort was in finding (multi-step EEVA star hopping) the thing...

I observed 3C 273 a couple of nights back:

https://stargazerslounge.com/topic/374487-from-near-to-very-far-quasar-3c-273/

I did also managed to observe the outburst of the blazar CTA-102 that @Owmuchonomy mentions here:

https://stargazerslounge.com/topic/374482-whats-the-furthest-away-thing-youve-imaged/?do=findComment&comment=4061446

That latter one is the most distant object that I've observed.

 

[Clarkey]

4 hours ago, Astro Waves said:

I think there's a total of 2:20 of integration time maybe. I might keep going on it as well. Let me know what you think.

I think that is a pretty good effort - well done. A little more integration time will always help, but for 2.5 hours that is pretty good. Nice star colours too.

What scope are you using?

[Clarkey]

Duplicate post

Edited March 26, 2021 by Clarkey
Duplicate

[wimvb]

4 hours ago, Astro Waves said:

So the Whale Galaxy is now my furthest away object I've intentionally imaged at 30 Mly.

But unintentionally, you cast a much wider eye on the sky.

To the left side in your image, is an area with a very nice distant galaxy cluster [SPD2011] 9429

I have indicated its brightest members, two galaxies with a redshift of 0.132. This puts them at (don't start swearing now) 1.7 billion light years distant.

To show them better, I took a crop from your image, inverted and superstretched it.

[wimvb]

9 hours ago, Astro Waves said:

Do the imaging settings need to be the same when imaging on multiple nights?

They don't, but life is easier if you leave them the same. You can alter exposure time, but you may need to take new darks. You can rotate or shift the camera, but you will need new flats and will lose area in the final image, because you need to crop the stacking edges. Once you manage plate solving in the field, your pointing accuracy will be much better and you can keep more of the subs in the final image.

One way to get repeatable framing is to align your camera with RA and DEC. To do so, take a 30 s exposure. While the exposure is running, move the mount at sidereal rate in RA only. This will create star trails in the RA direction. Rotate your camera "into" the trails, ie until the trails are parallell with either the long side or the short side of your camera sensor. If you do this, any misalignment is only a shift in RA or DEC, which is much easier to correct.

[Astro Waves]

1 hour ago, Clarkey said:

I think that is a pretty good effort - well done. A little more integration time will always help, but for 2.5 hours that is pretty good. Nice star colours too.

What scope are you using?

Thanks very much. I'm using a redact with an astro mod Canon 750D, I have to do some cropping but not too bad. How much worse is things such a heavy moon lit nights for galaxies? Would it be worth getting a some kind of filter to help out? That is the next thing I'm looking int really as for now the setup I've got is running pretty nicely.

 

50 minutes ago, wimvb said:

But unintentionally, you cast a much wider eye on the sky.

To the left side in your image, is an area with a very nice distant galaxy cluster [SPD2011] 9429

I have indicated its brightest members, two galaxies with a redshift of 0.132. This puts them at (don't start swearing now) 1.7 billion light years distant.

To show them better, I took a crop from your image, inverted and superstretched it.

I'm sorry....you what? one.......point......seven......billion? WWWWOOOOOOWEEEEEE! well I'm pretty darn happy with that! I did try using Astrometry earlier but didn't come up with anything that coooool! Also how do you find out info like that?

 

22 minutes ago, wimvb said:

They don't, but life is easier if you leave them the same. You can alter exposure time, but you may need to take new darks. You can rotate or shift the camera, but you will need new flats and will lose area in the final image, because you need to crop the stacking edges. Once you manage plate solving in the field, your pointing accuracy will be much better and you can keep more of the subs in the final image.

One way to get repeatable framing is to align your camera with RA and DEC. To do so, take a 30 s exposure. While the exposure is running, move the mount at sidereal rate in RA only. This will create star trails in the RA direction. Rotate your camera "into" the trails, ie until the trails are parallell with either the long side or the short side of your camera sensor. If you do this, any misalignment is only a shift in RA or DEC, which is much easier to correct.

I think I understand most of that, might have to read it again a couple times though.

Edited March 26, 2021 by Astro Waves

[wimvb]

3 minutes ago, Astro Waves said:

I think I understand most of that, might have to read it again a couple times though

Time to get the "bible" of astrophotography:

https://www.firstlightoptics.com/books/making-every-photon-count-steve-richards.html

[Clarkey]

3 minutes ago, Astro Waves said:

How much worse is things such a heavy moon lit nights for galaxies? Would it be worth getting a some kind of filter to help out? That is the next thing I'm looking int really as for now the setup I've got is running pretty nicely.

I think with some moon at 90 degrees or so to the target is not too bad for brighter galaxies. Beyond about 50% you will find it harder. I tend to go for narrowband once the moon gets too full. However, I did manage an M51 around the full moon - but I did get 17 hours of data. Even then it was not brilliant. I don't use a lot of filters so I can't really help too much with the best for moonlit nights. You could possibly look at one of the dual band filters - they seem to give some nice results.

[wimvb]

The moon is just another bright light bulb in the sky. As with sunlight, moonlight will turn the sky blue, just less so than sunlight. And as with daytime b/w imaging, using a red filter will suppress that blue, giving more contrast. That's why Ha imaging works during a full moon. Using a red filter with a mono camera will also work to some extent. But if you plan to image blue nebulosity (reflection nebula or Oiii), you better wait for the moon to be out of the way.

[Astro Waves]

2 hours ago, wimvb said:

Time to get the "bible" of astrophotography:

https://www.firstlightoptics.com/books/making-every-photon-count-steve-richards.html

Oooohhh that looks good, might have pick myself up a copy.

2 hours ago, Clarkey said:

I think with some moon at 90 degrees or so to the target is not too bad for brighter galaxies. Beyond about 50% you will find it harder. I tend to go for narrowband once the moon gets too full. However, I did manage an M51 around the full moon - but I did get 17 hours of data. Even then it was not brilliant. I don't use a lot of filters so I can't really help too much with the best for moonlit nights. You could possibly look at one of the dual band filters - they seem to give some nice results.

17 hours? not messing around there, is there pic I can see? For galaxies or any deep sky object do you just generally go for the most amount of integration time you can do or do you find there are limits to certain things? I have been looking at dual narrow band filters, I'm just trying to figure out whats best to shoot once the moon starts kicking off but trying to go for informed decisions on buying kit mainly because upgrades on anything for me will be few and far between.

I just wanna say you lot seem so helpful on this forum its great. I don't know anyone else that does AP so I can't just constantly pester them with questions, I massively appreciate all the help.

 

 

[Clarkey]

7 hours ago, Astro Waves said:

17 hours? not messing around there, is there pic I can see? For galaxies or any deep sky object do you just generally go for the most amount of integration time you can do or do you find there are limits to certain things? I have been looking at dual narrow band filters, I'm just trying to figure out whats best to shoot once the moon starts kicking off but trying to go for informed decisions on buying kit mainly because upgrades on anything for me will be few and far between.

I'm not sure how to link to another post, but if you search 'M51 in a full moon' you will find my post. I did have a few technically issues which did not improve things. There is also a post of M106 taken with a first quarter moon which was more 'normal' integration time of 5 hours.

In terms of integration time it is a diminishing return as you increase. It's all about improving signal to noise ratio. I don't normally do 17 hours but I had 3 clear nights in a row so I thought I would try. Imaging during a full moon meant I needed more than normal due to the increased background brightness. I think you need to try your kit and see what works. I have only been imaging for less than a year so I am still learning myself. Also, it was a new scope so I was still experimenting. I think your Redcat will come into is own for widefield work.

You are right about choosing kit carefully. AP is expensive. I was in a lucky position to have some spare money last year which is why I have got so much kit so quickly. (My first scope/mount was January last year). However, with relatively modest kit it is possible to get some great results. Keep looking on this forum and asking questions - everyone will do their best to help.

 

[wimvb]

56 minutes ago, Clarkey said:

I'm not sure how to link to another post

Open that post in another tab in your browser. Copy the address and paste in a post here. That's it. It will link automatically.

[Starwiz]

I think I've found a quasar in one of my images from last year, that is near M101.  I only know this based on a post I saw on CN.

What is the best way to validate this if I don't know the name of the quasar?

John

[wimvb]

3 hours ago, Starwiz said:

I think I've found a quasar in one of my images from last year, that is near M101.  I only know this based on a post I saw on CN.

What is the best way to validate this if I don't know the name of the quasar?

John

simbad and aladin

https://aladin.u-strasbg.fr/AladinLite/

Enter M101 in the target field en hit enter. Then move the fov to the suspected quasar. Activate SIMBAD on the right hand side of the display.

Use the bulls eye (left hand side of the display) to get more information on any target. Or click the small boxes that are activated with SIMBAD. Other than that, just play with it.

[Starwiz]

2 hours ago, wimvb said:

simbad and aladin

https://aladin.u-strasbg.fr/AladinLite/

Enter M101 in the target field en hit enter. Then move the fov to the suspected quasar. Activate SIMBAD on the right hand side of the display.

Use the bulls eye (left hand side of the display) to get more information on any target. Or click the small boxes that are activated with SIMBAD. Other than that, just play with it.

Thanks, that's great.

Here's my contribution:

Quasar [VV2006] J140354.6+543246

Magnitude:  20.69

Redshift:  3.258

Lookback distance:  11.8 billion years

Indicated by the yellow markers in the image.

[iapa]

On 24/03/2021 at 23:38, Astro Waves said:

Just curious on this one as I've currently got my camera going on NGC 4631 - Whale Nebula.

And it literally blew my tiny mind that it was 30 Mly away from us. I actually took a quick video on me phone of the computer screen and sent it to a few friends even though it was just the first single image I captured of it that was badly edited and looked like a small smudge, but it still blew my mind! Because of the moon phase I've got some shorter exposures going (80 secs) but its been going for at leat an 2 hours and I'll stay up an wait as well to see what happens!

Are you asking the furthest that has been targeted or, the furthest in an image.

The latter will be very hard to determine.

[Astro Waves]

I was meaning the first one but either is pretty interesting to know really.

[Xilman]

On 26/03/2021 at 16:15, Macavity said:

Aside from not too difficult (DOT-like!) 3C273, the "Hubble Deep Field".
- Or rather the "faintest" and (in this case) not too attractive an image? 🥳
Most of effort was in finding (multi-step EEVA star hopping) the thing...

[removed word] attractiveness!

If you've got it, flaunt it.

[Marvin Jenkins]

My meager contribution is 126mlys NGC 4388 in Markarians Chain.

In fairness I had no idea it was there initially but it is a galaxy with shape not a fuzzy blob.

I have attached my very first MC attempt and biro doodle of all the galaxies I could identify with distances.

Marv

 

[Astro Waves]

Nicely done. I like the biro doodle, makes it feel more scientific!

[wimvb]

10 hours ago, Marvin Jenkins said:

My meager contribution is 126mlys NGC 4388 in Markarians Chain.

In fairness I had no idea it was there initially but it is a galaxy with shape not a fuzzy blob.

I have attached my very first MC attempt and biro doodle of all the galaxies I could identify with distances.

Marv

 

Ic 3355, 3363, and 3393 are all about 16-18 Mpc distant (multiply Mpc by 3.26 to get Mly). According to vizier.

[whitfieldp]

Since the post referencing Astrobin was posted on 13 April, the same day I posted my Astrobin image there's a better than average chance that the Owl Nebula image with the position of QSO J111504.4+55043 marked was mine. (label in image has a typo 🙄)

https://www.astrobin.com/sprrw0/B/?nc=user

I've since followed that up with two other QSO images...

QSO APM08279+5255 is supposely the most distant object that can easily be seen with amateur equipment (due to gravitational lensing) with a light travel time of just over 12 billion years (red shift of 3.9). It's magnitude +15.2 so it's not hard to catch as a tiny dot in amongst lots of other tiny dots, but the frame doesn't look very picturesque if that's what you're after.

https://www.astrobin.com/tbb34u/?nc=user

The twin quasar QSO 0957+561A and B on the last night of astro-dark a couple of days ago after seeing it on a Galactic Hunter video. This isn't is distant with a red-shift of 'only' 1.4 but was the first identified object showing gravitational lensing. It's magnitude +16.7 and I managed to split it with my 102mm APO with 300s subs. Theoretical separation is about 2 pixels for my image train so quite a challenge for the mount

https://www.astrobin.com/kr0dsn/D/?nc=user

Another good resource for identifying many quasars is the optional Hyperleda catalog for ASTAP that will identify objects after plate solving. Stellarium has a decent quasar plugin as well that has the brighter ones.

Pam

Edited May 13, 2021 by whitfieldp
add link to Owl

[whitfieldp]

On 26/03/2021 at 19:55, Clarkey said:

I think that is a pretty good effort - well done. A little more integration time will always help, but for 2.5 hours that is pretty good. Nice star colours too.

What scope are you using?

One thing to bear in mind is that all things being equal Poisson counting statistics go as square root of the counting time. Halving the noise to impact the signal-to-noise needs quadruple the counting time. That being said the variation in sky conditions means things aren't equal. Replacing data from nights with iffy conditions with data from good conditions can have a massive impact on the final image. Throwing out a full night of subs can be a bit painful but can pay dividends. It's always subjective figuring out when you've reached the point of diminishing returns but you do get to the point where another hour really doesn't do much

[Marvin Jenkins]

I was of the understanding via the post from the OP on April 24th that they meant the most distant object targeted.

I maybe wrong #whitfieldp and please correct me if I am, but your post said that your Astrobin image was of the ‘owl nebula‘.

Is your image targeting the QSO or is the QSO a background object? I wanted to know as the definition of targeted, and happens to be in the background is fundamental to the OPs question. 

I found the rest of your answer utterly fascinating although I have to confess a little above my pay grade. Although a lot of what you posted has me delving for more information.

Marvin

[Marvin Jenkins]

Super well done on the gravitationally lensed quasars though. Great job.

M