Imaging with the Samyang 135mm f2

[Space Oddities]

The Samyang is a keeper! I think it's worth the extra cost versus cheaper/older lenses. Being able to shoot wide open and still get a decent result is a great advantage.

I've had zero time for astro in the last year, due to moving back to France, starting a new job, moving between different temporary homes, etc. But I couldn't resist to bring the Samyang with me, "just in case". My current temporary home happens to be in a suburban area with a fair amount of stars visible. Probably a Bortle 4.

The other day, I didn't have much motivation for a long AP session, plus it was first light for my new RST-135, so you never know what can go wrong. So I thought, why not keep it simple and try some EAA. Turns out, it was really nice! The RST-135 performed flawlessly, and the Samyang also worked well, even though I noticed some back spacing issue I need to solve. I used the ZWO ASI178MM-Cool and Baader filters. Didn't have a luminance filter in the wheel, only room for Ha, OIII and RGB. But that didn't stop me from enjoying the night sky from the comfort of my car, a good TV show on my iPad and an occasional look on what the ASIAIR is capturing.

Here are some of my observations that night, all are single exposures at f/2, mainly with the Ha filter and one of the RGB filters   No processing, just the autostretch from the ASIAIR.

 

 

 

[Uranium235]

Bubble, Cave, Lobster, Wizard

16x450 (Ha)

[Uranium235]

Flaming Star and Tadpoles:

16x900 (Ha)

[Adreneline]

Not posted in this thread for quite a while.

This is three sessions using the Samyang+ASI183MM with Astronomik 6nm Ha 2" filter.

So often it seems we only get a clear night when the Moon is up and lighting up the whole sky making OIII and SII difficult if not impossible. I might get lucky one day and get some decent OIII and SII to add to this which results in some synergy and a better overall image rather than a compromised colour rendition.

This is the current rig. I have put a lot of time and effort coming up with this arrangement trying to optimise the spacing and ensure there is no misalignment in the imaging train. I really don't think I can improve on the star shapes any more. The ASI183 is a great partner to the Samyang 135mm especially when used with a 49mm step down ring which slows the system to f2.63 and improves the peripheral stars whilst not adding spikes and unwanted facets.

Thanks to @geeklee for help with the design for the 3D printed parts - and to the brother-in-law for printing them!

Adrian

 

[geeklee]

On 21/01/2022 at 14:17, Adreneline said:

This is the current rig. I have put a lot of time and effort coming up with this arrangement trying to optimise the spacing and ensure there is no misalignment in the imaging train. I really don't think I can improve on the star shapes any more.

Recent subs suggest you've hit a sweet spot with the latest setup.  Nice shot with the "under the L" focus clear 😉

Adding one more to the thread, here's a six pane mosaic of a small piece of Orion.  Around 5 hours of data captured across a few nights - not all of which were very good quality - with a few patchy areas where I didn't get as much data on 1 or 2 panes.  The Samyang had the 183MM camera stopped down to ~F2.6.

[Space Oddities]

Superb capture! Any plan to add some color?

[Adreneline]

11 minutes ago, geeklee said:

with a few patchy areas where I didn't get as much data on 1 or 2 panes. 

Your processing skills are clearly spot on because there is no evidence of any "patchy areas". I love the way Barnard's Loop is included in the f.o.v. - excellent framing.

The pixels might be small but the aperture is large and it is a winning combination and well worth sharing.

[Phillyo]

Another M42 image with the Samyang 135, this is at f3.6 (using stop down rings) with the ASI533 and the Antlia 5nm filter. Love this combo!!

[geeklee]

11 hours ago, Space Oddities said:

Superb capture! Any plan to add some color?

Thanks Pierre.  No plans at the moment but it would be awesome to get an HaRGB image - it's the constant battle against clear skies really 😐 

11 hours ago, Adreneline said:

I love the way Barnard's Loop is included in the f.o.v. - excellent framing.

Thanks Adrian.  Me too, I really like where a bit of this is shown in an image of Orion - close in on something or far out framing things.

Here's one more wider shot that includes the Jellyfish nebula (IC443). M35, NGC2158, Monkey Head nebula (NGC 2174) and Lower's nebula (Sh2-261).  This is 3 panes with the Samyang and 183MM - between 15 and 30 minutes per pane so not much.

Edited January 25, 2022 by geeklee

[Adreneline]

3 hours ago, geeklee said:

Here's one more wider shot that includes the Jellyfish nebula (IC443). M35, NGC2158, Monkey Head nebula (NGC 2174) and Lower's nebula (Sh2-261).  This is 3 panes with the Samyang and 183MM - between 15 and 30 minutes per pane so not much.

Another great panoramic image that reveals so much about these objects in context, and not just their position but their relative size.

Whilst we're at it I just can't resist joining in.

This is a hastily processed 6 pane mosaic but pretty heavily cropped (as can be seen from the annotated version - which is not as pretty as yours so I need to look at my PI settings!). This image includes the Christmas Tree Cluster, Hubble's Variable Nebula, The Rosette Nebula and Sh2-284.

 

15 hours ago, geeklee said:

Adding one more to the thread, here's a six pane mosaic of a small piece of Orion.

Maybe we should join forces to fill the gap (not sure there is much in there though ) and join your Orion wide field image to my Cone, Rosette, Sh2-284 image and produce a mega-wide-field image!

I would like to add OIII to the whole lot but clear moonless nights are fewer in number than Dodo birds these days.

Adrian

Edited January 25, 2022 by Adreneline
Typo - resized image

[geeklee]

1 hour ago, Adreneline said:

This image includes the Christmas Tree Cluster, Hubble's Variable Nebula, The Rosette Nebula and Sh2-284.

That's a cracker and just stuffed with different areas to enjoy!  A great example of the extended nebulosity from the Rosette and it's interactions.

1 hour ago, Adreneline said:

Maybe we should join forces to fill the gap (not sure there is much in there though ) and join your Orion wide field image to my Cone, Rosette, Sh2-284 image and produce a mega-wide-field image!

APP just got it stitched!  A smidgen of black to fill in around the periphery 😅

[Adreneline]

2 minutes ago, geeklee said:

APP just got it stitched!

Amazing - just shows how good APP is at creating mosaics.

2 minutes ago, geeklee said:

A smidgen of black to fill in around the periphery 😅

A couple of nice clear nights and the jobs a good 'un! I'll do bottom left and you can do top right  

[Space Oddities]

On 24/01/2022 at 22:11, Phillyo said:

Another M42 image with the Samyang 135, this is at f3.6 (using stop down rings) with the ASI533 and the Antlia 5nm filter. Love this combo!!

Superb! I just received this filter, but my new apartment is still full of boxes and I haven't had a chance yet to set my equipment up.

This filter looks like an excellent companion for the 135, and seems to be dealing with halos pretty well too, compared to similar filters! 

[malftobe]

There are some absolutely stunning images on this thread.  A question for the mono camera users -  with the lens being f2, are you using regular (for want of a better word) filters or do you use filters for high speed systems?   

https://www.firstlightoptics.com/baader-filters/baader-high-speed-65nm-narrow-band-filter-cmos-optimised.html

 

[Adreneline]

1 hour ago, malftobe said:

A question for the mono camera users -  with the lens being f2, are you using regular (for want of a better word) filters or do you use filters for high speed systems?

In my case I use regular filters, in particular the Astronomik 6nm Ha and SII (both 2") and the Baader 8.5nm OIII (2"). I intend to replace the Baader with another Astronomik not because I am unhappy with the results but because being a different thickness the focus point ends up well before the 'L' on the lens. The Astronomik Ha and SII are very nearly parafocal and although I don't expect the Astronomik OIII to be "as parafocal" I hope it will certainly be better than the Baader. [Tip: Stick with one brand/type of filter and don't mix types or brands as you will make finding the optimal spacing really difficult if not impossible].

I am sure you already know this so apologies if you do but the spacing is incredibly sensitive. I currently have a 0.1mm spacer between the camera body and the 11mm spacer provided by ZWO. With the spacer in position the lens focuses almost exactly on the 'L'. If I remove the 0.1mm spacer the lens focuses about 2-3mm before the 'L' - if I add an additional 0.1mm spacer I cannot achieve focus at all. The Astronomik filters are 1mm thick - the Baader filters are 2mm thick. If I introduce spacers to achieve optimum focus with the Baader I cannot focus the Astronomik filters. In my current configuration (photo above) the OIII focuses about 3mm before the 'L' but at least the Ha and SII both focus "within the 'L'".

HTH

Adrian

 

[malftobe]

32 minutes ago, Adreneline said:

In my case I use regular filters, in particular the Astronomik 6nm Ha and SII (both 2") and the Baader 8.5nm OIII (2"). I intend to replace the Baader with another Astronomik not because I am unhappy with the results but because being a different thickness the focus point ends up well before the 'L' on the lens. The Astronomik Ha and SII are very nearly parafocal and although I don't expect the Astronomik OIII to be "as parafocal" I hope it will certainly be better than the Baader. [Tip: Stick with one brand/type of filter and don't mix types or brands as you will make finding the optimal spacing really difficult if not impossible].

I am sure you already know this so apologies if you do but the spacing is incredibly sensitive. I currently have a 0.1mm spacer between the camera body and the 11mm spacer provided by ZWO. With the spacer in position the lens focuses almost exactly on the 'L'. If I remove the 0.1mm spacer the lens focuses about 2-3mm before the 'L' - if I add an additional 0.1mm spacer I cannot achieve focus at all. The Astronomik filters are 1mm thick - the Baader filters are 2mm thick. If I introduce spacers to achieve optimum focus with the Baader I cannot focus the Astronomik filters. In my current configuration (photo above) the OIII focuses about 3mm before the 'L' but at least the Ha and SII both focus "within the 'L'".

HTH

Adrian

 

Very Helpful @Adreneline.  I've been window shopping filters for a while and noticed the  Astronomik filters are thinner than most.  Really interesting about the spacers for the different thickness for the filters and achieving focus.  May have to rethink using different brands for LRGB and narrowband.

 

This thread had led me down an interesting path this morning and I learnt a lot from @Phillyo's M42 widefield thread too.

[Adreneline]

21 hours ago, malftobe said:

May have to rethink using different brands for LRGB and narrowband.

The EFW on my RedCat contains both Astronomik NB and Baader LRGB filters. I very rarely do any LRGB imaging so I won't be changing any time soon - also spacing is not an issue in the same way with a RedCat. If I were starting afresh I would definitely stick to one brand of filter.

 

[PeterCPC]

Finally managed a go last night with the new rig from Canada that holds a guidescope and the Samyang. Only managed 21 exposures because I didn't feel very well. Anyway this was the result (centered on the Flame Nebula). No callabration subs, just lights run thro' APP. Each sub was 200 secs F2.8 with ASI533 uncooled.

[Uranium235]

On 26/01/2022 at 12:05, malftobe said:

There are some absolutely stunning images on this thread.  A question for the mono camera users -  with the lens being f2, are you using regular (for want of a better word) filters or do you use filters for high speed systems?   

https://www.firstlightoptics.com/baader-filters/baader-high-speed-65nm-narrow-band-filter-cmos-optimised.html

 

Regular filters will do. But as mentioned above, the thickness of the filter is a factor becuase it can have a massive effect of the amount of refocusing you have to do between filter changes.

Personally, I stick with 2mm as more manufacturers use that thickness.

[Uranium235]

Monkey Jelly @ f2   (15x450)

[AstroFin]

Fantastic images, everyone! This thread gave me the inspiration to get this lens and it has never let me down. 

Here's my recent shot of Orion and Barnard's Loop. Taken with the Samyang 135mm and a modified Canon 6D. 3hrs 25min of total exposure time. Further technical details on AstroBin.

[Uranium235]

One for the pixel peepers!

Extreme corner crops from the Jelly/Monkey image... not bad, can be better I think. Getting the focus nailed at f2 is a little tricky in Ha, at least I have the option to lock it now.

[Uranium235]

Orion - smash & grab

45min (6x450) x2 Ha

Bad LP, but a very good sky tonight. Could probably process it better, but not bad considering the time spent.

[powerlord]

very nice. is that with the asi ? I shot the same target/comp basically last night with my 6d +135. Not looked at subs yet but no way as good as that.

[Simon Pepper]

On 02/02/2022 at 17:29, Uranium235 said:

One for the pixel peepers!

Extreme corner crops from the Jelly/Monkey image... not bad, can be better I think. Getting the focus nailed at f2 is a little tricky in Ha, at least I have the option to lock it now.

Was this with a dslr or dedicated? Thanks