Imaging with the Samyang 135mm f2

[Mark1489]

A couple that I’ve captured using the samyang lately - both from my garden so not ideal when it comes to light pollution and challenging gradients to remove! About half hour on Triangulum and an hour on NGC 7000 (modified d5600 on that one!) 

Mark

 

[Chefgage]

North American nebula taken with a hydrogen alpha filter.

 6 x 300" lights and 40 bias.

Taken with a Canon 200D with Ha clip in filter, Samyang 135mm f2 lens on a star adventurer. Guided using a ASIAIR pro.

Stacked in DSS and processed in GIMP. Originally took 34 lights but had to delete all but 6 due to cloud and dew.

[nephilim]

I've just pushed the button on this lens after seeing what it's capable of. I'm re starting AP after a long break & rather than buying a scope I've decided to use this as it seems to be a lot less faff than a scope/dedicated camera.

[Chefgage]

3 minutes ago, nephilim said:

I've just pushed the button on this lens after seeing what it's capable of. I'm re starting AP after a long break & rather than buying a scope I've decided to use this as it seems to be a lot less faff than a scope/dedicated camera.

Hopefully yours will be delivered quicker than mine. I had to wait 8 weeks. 

[nephilim]

3 minutes ago, Chefgage said:

Hopefully yours will be delivered quicker than mine. I had to wait 8 weeks. 

Urgh, that's a lifetime mate. I found it cheapest on Amazon (£449) & received a msg about an hour ago saying it'll be delivered tomorrow. I only paid for it late last night.

[Phillyo]

I found mine on ebay for £290 which was a steal. Perfect condition too, hardly used and beautiful clean optics!

[nicoscy]

Just ran into this topic - nice images people! - and if of any use to anyone, Teleskop Service put this up on their site a couple of weeks back: Wega Tube Rings with Finder Shoe and Dovetail Bar for Samyang 135mm f/2 Lens

Edited December 4, 2020 by nicoscy

[nephilim]

3 minutes ago, nicoscy said:

Just ran into this topic - nice images people! - and if of any use to anyone, Teleskop Service put this up on their site a couple of weeks back: Wega Tube Rings with Finder Shoe and Dovetail Bar for Samyang 135mm f/2 Lens

Thanks for the link mate. I was just thinking how I was going to mount this lens as a I don't think a 1/4" photo thread on a dovetail will quite cut it.

[Phillyo]

I went with this guy http://www.astrokraken.fr/samyang-135mm-f-2-c30078976 I have the 3 ring version with 3 holders, 2 for the lens and 1 for the camera plus the micro focuser which is amazing for nailing focus!

Image of set up below.

Edited December 4, 2020 by Phillyo
Image added.

[Craney]

4 minutes ago, Phillyo said:

I went with this guy http://www.astrokraken.fr/samyang-135mm-f-2-c30078976 I have the 3 ring version with 3 holders, 2 for the lens and 1 for the camera plus the micro focuser which is amazing for nailing focus!

Image of set up below.

 

Yes, I totally agree. That third ring is such a useful addition. 

You just cannot get similar and consistent  levels of precision with fingers, gloves etc.....

[Space Oddities]

Looks like a nice 3D printed solution! I found it on the supplier's website, it's a bit cheaper (but in German): https://www.wega-telescopes.de/shop/Rohrschellen-passend-für-Samyang-135mm-F2-Objektiv-inkl-Sucherbasis-3D-Druck-p258368766

Another cheaper option is this one: https://shop.astrojolo.com/product/rings-for-samyang-135-f-2-lens/

I tried a few mounting options, but eventually settled with the William Optics mounting ring, that FLO sells separately for users who want to upgrade theirs (the V1 was different). It happens to perfectly fit the Samyang 135mm, I really like mine! It's also cheaper than the 3D printed ones. I added a 3D printed focus aid, the M48 mod sold by FLO -much better than the Canon connection!), and found a 360° rotator from TS-Optics that can host a 2" filter inside. Rotating the camera is much easier now, without touching the lens.

Sadly the ring and the M48 mod are out of stock now  

https://www.firstlightoptics.com/william-optics/william-optics-redcat-spacecat-single-mounting-ring-black.html

[nephilim]

14 minutes ago, Phillyo said:

I went with this guy http://www.astrokraken.fr/samyang-135mm-f-2-c30078976 I have the 3 ring version with 3 holders, 2 for the lens and 1 for the camera plus the micro focuser which is amazing for nailing focus!

Image of set up below.

Very nice set up. I'm going to use a DSLR to start with then looking at the ZWO ASI 533MC Pro. Although If my calculations are right (questionable) using the 135mm with the 533 will result in a resolution of 5.74 which I 'think' will lead to oversampling, may have to have a rethink on that. 
Do you have a price for this? Unless im blind I cant seem to find it on the website. Also, do you know the average turnaround time from purchase to delivery

[nicoscy]

Math is correct: Pixel size of camera  x 206 / Focal length = 3.76 x 206  / 135 = Resolution of 5.737

Edited December 4, 2020 by nicoscy

[Phillyo]

6 minutes ago, nephilim said:

Very nice set up. I'm going to use a DSLR to start with then looking at the ZWO ASI 533MC Pro. Although If my calculations are right (questionable) using the 135mm with the 533 will result in a resolution of 5.74 which I 'think' will lead to oversampling, may have to have a rethink on that. 
Do you have a price for this? Unless im blind I cant seem to find it on the website. Also, do you know the average turnaround time from purchase to delivery

That is the 533 that you see attached there and it works perfectly. The lens has a very high resolution so sampling at 5.74 is perfectly fine. I have a number of images up in the DSO area of the site if you want to have a look.

Pricing is tricky to find on that website, however if you click on the images, then click on "Do you need one?" it'll take you to this page for the prices of the various different parts. You can choose from a number of options to suit your needs http://www.astrokraken.fr/bracket-system-for-samyang-rokinon-135-f-2-telephoto-lens-a183920490

Phil

[nephilim]

20 minutes ago, Phillyo said:

That is the 533 that you see attached there and it works perfectly. The lens has a very high resolution so sampling at 5.74 is perfectly fine. I have a number of images up in the DSO area of the site if you want to have a look.

Pricing is tricky to find on that website, however if you click on the images, then click on "Do you need one?" it'll take you to this page for the prices of the various different parts. You can choose from a number of options to suit your needs http://www.astrokraken.fr/bracket-system-for-samyang-rokinon-135-f-2-telephoto-lens-a183920490

Phil

Thanks for that. Also great to hear that the 533 works well as its the camera I've had my eye on for a fairly long time. I'll check out your images. I'm highly excited about this lens.

[nicoscy]

I only do EAA, but considering a full moon and only 7 x 10 second frames stacked via ASIAir Pro and no calibration frames, the camera delivers. I used the ASKAR FMA180mm lens at f4.5 with the ZWO Duoband filter.

No post-processing, this is straight out of a screenshot at the 70 sec mark of a live stack view.

[nephilim]

6 minutes ago, nicoscy said:

I only do EAA, but considering a full moon and only 7 x 10 second frames stacked via ASIAir Pro and no calibration frames, the camera delivers. I used the ASKAR FMA180mm lens at f4.5 with the ZWO Duoband filter.

No post-processing, this is straight out of a screenshot at the 70 sec mark of a live stack view.

That's pretty impressive for such a short exposure time. The lack of amp glow & only having to take flats with this camera also appeals to me.

Edited December 4, 2020 by nephilim

[nicoscy]

I forgot to take a screenshot later in the stack, but noise dropped dramatically shortly thereafter. My point being, that while pixel size is a bit "largish" and pixel scale again, "largish", the camera can and does perform well under the constraints set by short focal length instruments, as evidenced by the lovely images in this thread (excluding my own as I do something different).

[Space Oddities]

At 135mm, it's anyway very difficult to find a camera with matching pixel size... Does it really matter anyway, at such short focal lengths? 

[geeklee]

On 04/12/2020 at 07:41, Phillyo said:

I went with this guy http://www.astrokraken.fr/samyang-135mm-f-2-c30078976 I have the 3 ring version with 3 holders, 2 for the lens and 1 for the camera plus the micro focuser which is amazing for nailing focus!

Image of set up below.

I think my setup (including camera and guide cam from another rig) will look very much like this when I get first light @Phillyo  Did you drill new holes in the Astrokraken rig to mount on to another dovetail?

This thread has been nagging away at me for ages and I finally succumbed recently and started building up the equipment.  The next 5-10 days look awful weather wise but we'll see if I can sneak at least an hour or two.

I have the ZWO Canon adapter from a previous project that unfortunately never went anywhere and it seems very solid when locked in.  I still have the FLO M48 adapter on order as I plan to try and use my Atik 460 as well - although this sounds more challenging from the information in this thread.

At some point I may be close to spending enough to have just bought a bigger camera to get the wider views 🤨

On 04/12/2020 at 08:03, nephilim said:

Although If my calculations are right (questionable) using the 135mm with the 533 will result in a resolution of 5.74 which I 'think' will lead to oversampling, may have to have a rethink on that. 

Maths correct, but that scale would typically be classed as undersampling rather than oversampling (@ 5.74"PP). As @Phillyo says, it can still look good with the ASI533 (and many other cameras), as his images show.

Edited December 5, 2020 by geeklee

[nicoscy]

27 minutes ago, Space Oddities said:

At 135mm, it's anyway very difficult to find a camera with matching pixel size... Does it really matter anyway, at such short focal lengths? 

Not that much I would guess, as you are not pixel peeping at that focal length and image scale...

[Phillyo]

2 hours ago, geeklee said:

I think my setup (including camera and guide cam from another rig) will look very much like this when I get first light @Phillyo  Did you drill new holes in the Astrokraken rig to mount on to another dovetail?

Yes I drilled a couple of extra holes to attach it to that dual mounting dovetail. Mostly because I ordered the wrong one by mistake!

[mAnKiNd]

Finished another one

https://www.astrobin.com/0z23pq/

[Chefgage]

9 hours ago, mAnKiNd said:

Finished another one

https://www.astrobin.com/0z23pq/

Very nice. I was wondering what to image next, you have given me a good idea.

[nephilim]

Its arrived & it's a lovely piece of glass