Simeis 147 (WIP)

[MartinFransson]

Well, I need a lot more data for this one! Anyway, here is a try at bicolour image of Simeis 147 - the Spaghetti Nebula.

67*5 minutes of 3nm Ha and 27*5 minutes of 3nm O3.
Samyang 135/2.0 lens @f/4.
ZWO ASI1600MM-Cool

[tooth_dr]

Data shortage or not, that’s pretty damn good! I’d be more than happy with that. 

[Craney]

May I ask why you shoot at F4 with the Samyang rather than the option for F2,  which would reduce the amount of exposure time (especially with narrow-narrow band filters) ??

(  BTW ....Spectacular image as it stands ).

 

Sean.

[MartinFransson]

26 minutes ago, Craney said:

May I ask why you shoot at F4 with the Samyang rather than the option for F2,  which would reduce the amount of exposure time (especially with narrow-narrow band filters) ??

(  BTW ....Spectacular image as it stands ).

 

Sean.

I just don´t get sharp stars in the corners at f/2. Even at f/2.8 I get some elongated stars in the corners.

[groberts]

Excellent image Martin, will look really great with some more subs!

I'm thinking of going the Samyang 135 route,just love the FOV and image quality - would be interested to know / see what your set-up looks like + any advice ?  

Given your comments regarding f2 v f4 - does that mean you always image at f4 or are there objects that work at the wider aperture?

Graham

[MartinFransson]

2 hours ago, groberts said:

Excellent image Martin, will look really great with some more subs!

I'm thinking of going the Samyang 135 route,just love the FOV and image quality - would be interested to know / see what your set-up looks like + any advice ?  

Given your comments regarding f2 v f4 - does that mean you always image at f4 or are there objects that work at the wider aperture?

Graham

It means I image at f/4, sometimes at f/2.8. I might have a less than perfect copy of the lens or something because I´ve seen people imaging at f/2.

Here are a few photos of how I set up. One with the Samyang and one with how I mount together with the guide scope. But in that picture it´s the Canon 300/4L lens I use

[groberts]

Thanks Martin, that's very helpful - think I'm sold on the Samyang 135 for astrophotography, love the big picture it achieves.

Any tips on focussing, I've always battled with this using a camera lens? 

Graham

[MartinFransson]

41 minutes ago, groberts said:

Thanks Martin, that's very helpful - think I'm sold on the Samyang 135 for astrophotography, love the big picture it achieves.

Any tips on focussing, I've always battled with this using a camera lens? 

Graham

These are the solution to that

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p3286_TS-Optics-Microfocuser-for-your-camera-lens-up-to-135-mm-Diameter.html

 

[groberts]

Thanks again, much appreciated.

Graham

 

Edited February 14, 2020 by groberts

[wornish]

Your image is superb. You make me want to try some wide field imaging.

I have the ASI1600MM and the EFW.

What version of the Samyang did you use ( Canon - Nikon ? ) and what adapter to connect to the filter wheel?

 

[MartinFransson]

2 hours ago, wornish said:

Your image is superb. You make me want to try some wide field imaging.

I have the ASI1600MM and the EFW.

What version of the Samyang did you use ( Canon - Nikon ? ) and what adapter to connect to the filter wheel?

 

I have the Canon version and I use the ZWO lens adapter for Canon lenses.

https://astronomy-imaging-camera.com/product/new-eos-lens-adapter-for-efw

[MartinB]

Excellent Martin, the OIII is popping out really nicely.  The 135mm lens frames this object perfectly.

[groberts]

Hi Martin,

I have just received my Samyang lens and like the idea of the TS-Microfocuser you mentioned.  

I make the relevant diameter of the lens barrel for this to be 73mm so the 80mm ring would work but the 105mm would provide more scope (no punintended) for other lenses.  Was wondering which of these you have / any thoughts?   

Graham

[Gina]

Fantastic image - wonderful   Must have been very clear sky.

What gain setting did you use?  I've been working on this but not achieved anything like your image!

Edited February 27, 2020 by Gina

[ollypenrice]

What a great result. This lens-camera combination gives an almighty FOV and tight stars in NB. Do you know how well the lens controls RGB stars?

Olly

[bob-c]

A lovely image.

Bob.

[gorann]

That is a truely great result Martin! Not sure why you talk about needing more data. It really makes me tempted to start imaging with my Samyang 135 again. My problem is too many scopes and too few (good) cameras (I got one more ZWO on order but who knows when the Chinese will start shipping cameras again). And of course too many clouds.

[MartinFransson]

On 27/02/2020 at 10:51, Gina said:

Fantastic image - wonderful   Must have been very clear sky.

What gain setting did you use?  I've been working on this but not achieved anything like your image!

Thanks Gina! Sorry for the late reply, been off the site for a while.

I always use unity gain for all my work.

[MartinFransson]

On 27/02/2020 at 12:35, ollypenrice said:

What a great result. This lens-camera combination gives an almighty FOV and tight stars in NB. Do you know how well the lens controls RGB stars?

Olly

Thank you Olly! Since I use the lens stopped down to f/4 it works very well.

[MartinFransson]

On 27/02/2020 at 19:09, gorann said:

That is a truely great result Martin! Not sure why you talk about needing more data. It really makes me tempted to start imaging with my Samyang 135 again. My problem is too many scopes and too few (good) cameras (I got one more ZWO on order but who knows when the Chinese will start shipping cameras again). And of course too many clouds.

Thanks Göran! Don´t you know that we ALWAYS need more data?

[MartinFransson]

On 27/02/2020 at 09:20, groberts said:

Hi Martin,

I have just received my Samyang lens and like the idea of the TS-Microfocuser you mentioned.  

I make the relevant diameter of the lens barrel for this to be 73mm so the 80mm ring would work but the 105mm would provide more scope (no punintended) for other lenses.  Was wondering which of these you have / any thoughts?   

Graham

Hi Graham! Sorry for the late reply! Weather has made me forget about astrophoto for a while...

I have the 105mm because I wanted to use it also for my 300 and 500mm tele lenses.

[tomato]

That’s a great image, reminds me of those high speed camera shots of the atom bomb tests in the 50’s, except the time scales are a bit different.