Xplode

5 hours ago, MartinB said:

A stunning image and interesting to compare with the IKI observatory image in the current SGL processing competition

Thank you!
IKI Observatory is actually at the same remote site as SkyEyE Observatory

With lots of bad weather this winter finished images has been few and far between, this isn't especially new, but "fell between the cracks" and didn't get fully processed till february even if it was imaged last year.

This was imaged at SkyEyE observatory hosted at IC Astronomy, Orio, Spain.
Processing done by Ola Skarpen and Ole Alexander Ødegård

97x60s R
120x60s B
97x60s G
415x60s Ha

In total 13.1 hours HaRGB

ASI6200MM Pro through a AG Optical Convergent 14.5"

Make sure to click on the image to open the full version!

On 06/10/2020 at 18:23, WJDrijfhout said:

Awesome combination and great early results! Could you share the adapters you've used? I am looking to connect the ASI6200 to the TOA-130 but with the same 67-FL flattener, so I guess it would be the same.

Also, what is the use for the OAG in your setup, if it is not for guiding? My setup is typically used unguided, so an OAG would probably not be something I'd get. 

Sorry for late reply, didn't see your post till now.
The OAG is there just as a M68 adapter, it was the only available solution to connect M68 adapters at the time the camera was bought. Today the M68 Tilt plate is an option, but in my opinion the ZWO tilt plate isn't very good, it's hard to adjust it very accurately
Adapters used were a Baader M72-M68 and of course some M68 extensions. There's also a stepdown adapter from the 67-FL flattener to M72, you most likely have this already since it's an original Tak adapter..

I'd advice you to use Sharpcap instead, it's a much better software and you will find more info about how to use it.
In Sharpcap you should use the .ser format for planetary videos, .avi is very outdated while .ser is made just for planetary imaging.
For stacking Autostakkert is the best choice, but for editing Registax is still a good choice.

1 minute ago, vlaiv said:

There is absolutely no difference.

This is old question asked by computer enthusiasts that over clocked their computers, many tests were done and results are the same - it does not matter.

Consensus is that push / pull configuration is the best   - as it uses two fans - one to push ambient air into radiator and another one to remove - thus creating steady flow.

There is a difference, but how much depends on the situation.
Remember pushing air directs it pretty well, but pulling air through a heatsink it will just pull where it's least resistance.
You can see a test done on a graphics card there
https://youtu.be/IJmE13sG9PI?t=719

In general it's best to have the fan push onto the heatsink rather than pull.

I'd rather say blowing air onto the heatsink

It's usually best to blow the cold air at the object that needs to be cooled, this is how, this is how 99% of all computers are setup

For visual there might not be that much of a difference, but for imaging it's a different story.
Remember the old focal reducer is also a coma corrector, the EdgeHD design doesn't have coma so it will correct for something that's not there so most likely it will introduce coma or some other abberation.

I wouldn't trust the numbers given by any manufaturere to be 100% correct, FL varies a little, flattener-sensor spacing changes a little etc.
FL often seems to be just a nice "round" number, due to manufacturing differences it will of course vary a little, especially for mirrors.
For spacing i found it's best to always plan for having to adjust at least +/- 1mm from the manufacturers given specs.

Adapters/spacers should ALWAYS be measured without the male threads.

The correct spacing should not be judged by focal length or anything else than how the stars look.

Olly has suggested 28-30 before so maybe his vision has changed 😂

In my opinion 20 is certainly too dark on a calibrated monitor. 

I might also mention that high gain is ok for luminance too, ive taken 60-300s exposureswith both slow and medium fast scopes. I haven't found a reason to use low gain on the asi6200 

19 hours ago, RobertI said:

Wonderful image, spent an enjoyable 20 minutes looking at the detail in that one. Some interesting galaxies too. There's an interesting looking object in the spiral arms, don't think it's a globular cluster, could be a galaxy seen through the spiral arms?

Might be a face on spiral?

I think so, there's also other galaxies that can be seen through the outer areas of M31.

 

3 hours ago, ollypenrice said:

Lovely image, very deep and yet totally unforced and natural. The colour, too, is unforced. Spot on.

Olly

Thank you! We will try to keep the colors for the next version after i gather new GB + Ha data for the next version (R is already done)

Great resolution as always with this camera!
When in your processing do you scale it down? I've found it's best to do after all other processing.
In my opinion your backgound is a little too dark, the value is around 20 for your image, a value of around 30 would look a lot better!

Background value in your image


After changing the background value

Before and after changing the background value, looks a lot better! (

On 26/09/2020 at 11:24, Allinthehead said:

Great M31 and a massive improvement on the older version.

Thanks!

Thanks for all the comments!

I've imaged M31 every fall getting better and better images and i'm done quite done yet it seems!
This is a mix of older CCD data from 2018 and newer CMOS data which are much higher resolution and goes deeper so it's easier to see all the far away tiny galaxies and the more individual stars in M31

Data from 2018
Moravian G3-16200 through a Takahashi FSQ130-ED with a 645 0.7x focal reducer (f/3.5)

22x300s R
14x300s B
20x300s G
22x600s Ha

Data from 2020
ASI6200MM Pro through a Takahashi FSQ130-ED

427x60s L

In total 15.6 hours HaLRGB

Thanks to Tommy Linnerud for allowing me to use his remote observatory and Ola skarpen for the processing.

Please click to check the full version which is downsized to 66% of the original image.

Annotated version showing some of the faint background galaxies (there's many more if you look around)

Old version


Is this my last M31 image? Probably not 😆

2 minutes ago, wimvb said:

And how many stone is the load capacity of your mount?

Depends on the weight of the stones 🤣

On 07/06/2020 at 12:42, gorann said:

Just a small correction: Baader filters are 2 mm thick.

It depends on the filters, 50.4mm and larger unmounted filters are 3mm while all the mounted and smaller unmounted filters are 2mm thick.

@james_screech How about just adjusting the exposure length or get a software with automatic color balancing like Pixinsight?
Remember that a "balanced" filter set blocks light to achieve that balance so you get lower SNR.

Just now, msacco said:

I've spent around an hour working on collimation, and I really think I got it quite good this time(still not very epxerienced with collimating)

Did you verify good collimation with your camera?

Something else to avoud when creating images to check collimation/tilt/etc is low altitudes, especially for color cameras there will be an effect from atmospheric dispersion that could skew the measurements.

By looking at your images it's either tilt or collimation which is the main issue.

You might want to take a startest to check collimation, use Sharpcap with short exposures, defocus a bright star and see how the donut looks.

To get images to analyze you should take images of the same spot all the time, i suggest an area without a nebula/galaxy or star cluster, analyze the raw images, not the stacked one.

Use shortish images and make sure they have good guiding.
Don't trust your readings unless you get 5+ images with pretty much the same results, a variance of 5% isn't usual from an image to the next.

To check if it's collimation, if possible rotate the camera 180 degrees to see if the abberation rotates with the camera or not.
If it's sag/tilt because of weight check images before and after meridian flip, abberation will rotate 180 degrees.

If you want good input on what the problem is you should upload some of your fits images.

I have found that the numbers on spacing given by the manufaturer is rarely to be trusted, i try to always have spacers to adjust +/- 2mm available.

 

1 hour ago, tooth_dr said:

I would need the camera for 1) imaging with my 1200mm fl scope via the OAG, and 2) using with a 9x50 finderscope and approx 500mm fl.

If you want to use the guidecam on a guiderfinder the ASI174mm isn't a good fit, the pixels are too large, so are the Lodestars pixels.
In that case the ASI290mm mini is your best choice.

1 hour ago, tooth_dr said:

Thanks again.  I have sold off two astro items in the past two days, so on the look out for a used Lodestar X2.  I missed Rays, but hadnt the cash at the time.  My wife has rightly put a curtailment on any 'big' astro purchases, so I'm selling off some unused stuff instead. 

If you want a really great guidecam get a ASI174MM-mini, it's much better than the Lodestar, lower noise, larger sensor, more sensitive, faster download. In my opinion it's the best guidecam for OAG right now.
The drawback is that it's quite costly.

2 minutes ago, wimvb said:

I thought of that, but that would only result in intensity variations. The wiggle you see, would be miles of amplitude for the satellite. 

I agree, here's an example of a rotating satellite.

2 minutes ago, dan_adi said:

It makes sense obviously. But what is the percentage regarding light loss for each of those elements?  

Uncoated glass loses around 4% due to reflections per surface, an uncoated camera lens could loose 50% of the light through reflections!

It's hard to say for exact because of the different coating used by different manufacturers, but i don't think 1-2% per surface would be a bad number to use.

Even with an open roof there will most likely be stagnant air in the observatory, especially for smaller observatories
An open door in the observatory would help, but even better a fan, i suggest a fan sucking the air out of the observatory. A simple floor fan would be great for testing if you'd like to try.

Do you have heaters on any of your mirrors? I've seen heaters with too high wattage totally ruin guiding/imaging. I recently helped a guy that had a heater on his guider finder and he instantly got better guiding by turning it off.
The fan you have on the newtonian could in fact be the cause for the oscillations, might be a bad fan? Try turning it off.
I usually recommend very good quality fans like noctua, it's also best to mount them with some kind of rubber mounting

I believe the guiding assistant gives you exposure values based on the polar alignement/drift rate, i suggest you at least try longer exposure to see how it affects the guidegraph.