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3 hours ago, Knight of Clear Skies said:

Amazing vista, but is the background a touch green?

oh yeah it is  never saw it

54 minutes ago, Pankaj said:

Also if you could tell about the imaging camera you used.

It’s a canon dslr, but modified so the sensor is quite a bit more sensitive.

43 minutes ago, Pankaj said:

Thanks. You sure have loads of equipment. Going by your experience, do you think shooting this object is possible with a Skywatcher 130 PDS on guided NEQ6 from Bortle 3 sky?

I am a novice and your image has really inspired me. 

It’s possible but it may be tough. The 130pds is great I love mine, but this target is full of tiny faint galaxies. 130pds will struggle on these faint objects, also the wider field of view of the 130pds means these small galaxies in my pic will appear even smaller

If you are a novice, as you mentioned, I would use the 130pds on brighter bigger subjects and play around. Try the M51 or M101

have fun!

3 minutes ago, Pankaj said:

Awesome picture. Please do share equipment and capture details. I

ah yes of course.  60 x 5min lights, darks/bias/lights calibrated.  Canon 550d with Skywatcher 250 Quattro CF, Mounted on Neq6 Pro, ZWO ASIAIR did all controlling.

Getting fixated with the Coma cluster. It is just magical, just how much space and time are we looking at here with this photo 

added another 2 hrs to it now totalled 5hrs, and drizzled x2 to get more room to play when processing, my Stone Age laptop was little slow on the 700mb original TIF.  I think this is as far as I will go. I got more faint tiny galaxies’ data to play with after the additional 2hrs

13 hours ago, Philip R said:

Can they be used with catadioptics as well?

It says on TS-Optics "...for Newtonian telescopes..."

I won’t recommend it, same way I have never heard a Cheshire eyepiece used on a catadioptric 

13 hours ago, alacant said:

Hi and thanks for the report.

Is the acrylic with the rings transparent? Is there a 45° cutout a la Cheshire sight tube?

TIA

The acrylic is transparent. There isn’t a 45* cutout , the concept of the concenter tool bypasses the need of one.  But, there is a glow-in-the-dark version of concenter now

26 minutes ago, MarkAR said:

Good calibration frames and careful processing will go a long way.

Couldn’t agree more.  The pain of shooting with dslr is that I cant control the temperature and shoot darks at a later time.  

after 3 hrs on the lights, it’s tough to stay up another hr and half to shoot the darks.  

but it really is worth the effort.  I brew a cuppa, and watch an episode of something to keep me awake

Want to expose this tool called “concenter” that was introduced to me by @Captain Magenta.   It’s not talked about too much surprisingly, and I cannot find much info on this tool on the net.

Costs £70-ish posted from Germany’s TS-optics.  It is a transformative collimation tool that will get your mirrors about perfectly aligned, if you don’t want to spend £00+ on Howie Glatter or Catseye

Little under 2 years ago I was thrilled to get a 10” F4 Quattro CF reflector from a SGL member, I was very much into imaging already with my 130pds.

Then I hated my 10” Quattro ! I heard it is hard to collimating, but I had plenty of mirror fiddling experience with the 130pds and a big visual dob.   If it wasn’t for its dazzling good looks and girth, I would have sold it by now

Then I was lent the “concenter collimating 2’ eyepiece” to try out.  And immediately realised how bad my collimation was, the concenter revealed every fine-margin errors. That was exciting, with the errors visible, I can correct them.

Concenter is like a Cheshire, but with an acrylic plate at the bottom with concentric circle patterns.  

1st with the primary mirror covered up, i could accurately line up the secondary mirror to the focuser.  Uncovering the primary mirror,  the concentric circle patterns helped lining the primary to the secondary with ease.  And finally tweaking the primary, the centre mark of the primary mirror Is reflected back correctly to the secondary.    If you have seen how a Howie works, basically this tool attempts the same but instead of the convenience of having concentric circles projected onto the mirrors, you look through this tool to see the circles. 

i now love my light bucket photon eating 10” F4 Newtonian. 

think £70+ for this tool is a little expensive for what it is, but with so many DIY astronomers here with a 3D printer, you can fabricate this tool cheap and sell them 

1 hour ago, vineyard said:

As I suspected. This is nominally the same object 😂 but from Bortle 8/7, 72ED. To borrow a line from Jaws, I'm going to need a bigger scope for this one!

Stay safe,

Vin

Am thrilled my little photo still receiving attentions 😁.  I have plenty of noisy pictures that I hide from the world.

9 hours ago, jiberjaber said:

That's great, I've got about 16 hours of data from my D7500 and sliming that down to the better frames (13hrs) I'm struggling to get near that, would love to know more details.... scope/software/crop etc?

Thanks am surprised too with the clean data, largely luck to be honest, it was a absolutely perfect seeing night when I shot it, and I dithered every two frames

it was shot with SW250 quattro, processed in Pixinsight. I followed a few YouTube tutorials as I don’t have a set work flow yet

13 hours ago, CloudMagnet said:

Wow, what bortle sky was this shot from?

Bortle 4, I use the astronomik cls filter which I think it’s pretty good 

26 x 5 min exposure. Still loving my little 550d DSLR

Don’t know how I did it still, but straight out of the DSLR the stacked image was with minimal noise.

Modded Canon 550d, CLS filter, SW250 Quattro with dedicated CC. 36 x 5min subs, flat/dark/bias calibrated

After having some fun with the Markarian’s Chain, the next night I turned my scope towards the Coma Galaxy Cluster.  I stumbled across this area when randomly surfing on SkySafari  and was mesmerised by how many visible-to-DSLR galaxies can exist in a single framable space 

I found it very hard to tease any colours out of my data, do you think I need few more hours of exposures for colours? 
 

Modded Canon 550d with CLS filter, SW250 Quattro CF with aplanatic CC.  36 x 5m exposures
 

Would love any comments, especially how do you think I could get some colours in (more data?shorter exposure? ....)

Lovely, this is my plan target when the clouds clear 

bravo mate

On 17/04/2020 at 11:25, jimjam11 said:

After 3 months of acquisition on M51 I think I have reach the point of diminishing returns @ 15hr of integration. In truth I only got a couple of hours in Jan, 0 hours in feb, a few more hours in March and the rest in April. Clear weather kept falling around the full moon so this has taken way longer than it should have! Seeing was generally average until my last run a few nights ago; The luminance stack has a FWHM of 2.68" but for most of the 14/04 night subs were < 2.2" with some dipping below 2". 

Just over 10h of Lum, and 90m per channel for RGB. 

Annotated version:

so good, I am a little bit of a Newtonian Die hard fan, I think in good hands these cost effective scopes are every bit as good as £1k+ refractors

what camera did you use?

On 15/04/2020 at 20:28, Stub Mandrel said:

Hope you don't mind but I took a screen grab of your image, made a selection around the galaxies, inverted it and ran Gradient Exterminator on coarse/strong. There's a similar tool in pxinsight, if you run it on the full image the end result should be pretty impressive!

Wow you got rid of the vignette sooooo good.  I need to learn more on how to get rid of gradient. I just got myself photoshop so need to experiment a lot more

Markarian’s Chain, taken early March when a few clear nights presented themselves 

SW130pds, modded canon 550d with SW aplanatic CC, astronmik CLS filter, 2.5hrs worth of 5min subs, DSS stacked and PI processed with final touches in Lightroom.  I recently started to use dithering and now I know what “dither or die” means

I am planning on capturing more data on a target I had done before last year 

do I stack old raw files with the new ones captured?

 Or can I actually stack the new raw files,  with the single “stacked” output from the past raw files?

4 minutes ago, Stu said:

Have another look, there is a nice sunspot group in white light showing currently.

Oh yeah, and actually another prom at 3 o’clock, small needle (probably bigger than earth)

only have a PST so playing around keeps finding new features

Quite a tall triangular prom at 8 o’clock region. Some surface details no sun spot

Beautiful, nice capture 

Phewww least you saved the secondary!

2 hours ago, Captain Magenta said:

I decided to re-test the primary-mirror axis and Baffle/focus-tube collimation with the external focuser attached, as the external focuser likely has its own axis. Sure enough, it was slightly off (the laser in the focuser pointed at a point 2-3mm different from my artificial star and its coincident reflection from the primary). I shimmed the meeting-face of the Revelation focuser on its rotatable dovetail-ring, and established that there is one position where all three dots coincide. I set it there, and locked it down.

To do that, though, I had to remove again the secondary-mirror boss to create a hole for the laser to get through. In the process of doing that, THE SECONDARY MIRROR FELL OFF!!! Wow. As the picture shows, the glue was very old with almost no "stick" left. I'm glad it did, as it would otherwise likely have happened at night in the cold while the scope was pointed up. And would therefore have landed on the primary.

I also removed the not-especially useful central pin the the middle of the secondary front-plate, and will keep it removed to allow a permanent hole for a laser to be able to shine through. I'll keep it covered with some sort of plug or tape though.

I re-glued the secondary to its plate, and it's now curing:

I had planned to start fine-collimating the scope today with an artificial star at the bottom of my garden, but this episode put paid to that.