Imaging with the Samyang 135mm f2

[Space Oddities]

 

16 minutes ago, nephilim said:

Can anyone point me in the right direction for a good quality Bahtinov mask that will fit my 135. I bought a 3d printed one which cracked so I dont want to go down that road again (I wouldnt trust anything 3d printed really as my printed mounting system cracked as well a few weeks ago 🙄)

TIA
Steve

I'm using this one from William Optics. It's pricey, but it's solid and has the advantage to be transparent, which makes spikes more visible than opaque masks. It can also be used on your other scopes with a diameter up to 110mm, which is quite practical  

https://www.firstlightoptics.com/bahtinov-focus-masks/william-optics-bahtinov-mask-for-dew-shield-diameter-75mm-to-110mm.html

Edited August 16, 2021 by Space Oddities

[MARS1960]

17 minutes ago, nephilim said:

Can anyone point me in the right direction for a good quality Bahtinov mask that will fit my 135. I bought a 3d printed one which cracked so I dont want to go down that road again (I wouldnt trust anything 3d printed really as my printed mounting system cracked as well a few weeks ago 🙄)

TIA
Steve

You could try this If you want to keep it cheap Steve.

http://www.deepskywatch.com/Articles/make-bahtinov-mask.html

[nephilim]

3 hours ago, Space Oddities said:

 

I'm using this one from William Optics. It's pricey, but it's solid and has the advantage to be transparent, which makes spikes more visible than opaque masks. It can also be used on your other scopes with a diameter up to 110mm, which is quite practical  

https://www.firstlightoptics.com/bahtinov-focus-masks/william-optics-bahtinov-mask-for-dew-shield-diameter-75mm-to-110mm.html

I'd seen this one but forgotten where. Thanks for that 🙂

[nephilim]

3 hours ago, MARS1960 said:

You could try this If you want to keep it cheap Steve.

http://www.deepskywatch.com/Articles/make-bahtinov-mask.html

Cheers for the link mate but i'm useless at making things 😂 I think i'll go with @Space Oddities one.

[daemon]

40 minutes ago, nephilim said:

Cheers for the link mate but i'm useless at making things 😂 I think i'll go with @Space Oddities one.

I've been using one I bought from FLO for an ED80. I tthink it cost about £16. 

I know that masks should be optically matched in terms of focal length but I have found I can get perfect focus with the ED80 mask on the Samyang 135. 

Might save you a few pounds.

Cheers,

Steve

[nephilim]

22 hours ago, daemon said:

I've been using one I bought from FLO for an ED80. I tthink it cost about £16. 

I know that masks should be optically matched in terms of focal length but I have found I can get perfect focus with the ED80 mask on the Samyang 135. 

Might save you a few pounds.

Cheers,

Steve

@daemon Thanks Steve, I've only just seen your reply & have literally just pressed the button on the WO one (It must be made of unicorn tears for the price) I very nearly emailed FLO to cancel but then realised it'll also fit my upcoming Sharpstar 100QII so its not all bad 🙂

ATB
Steve

Edited August 17, 2021 by nephilim

[powerlord]

 

Edited August 17, 2021 by powerlord

[powerlord]

Yo - just printed up this uber-portable setup for travelling.

Print design is this one:

https://www.thingiverse.com/thing:4667525

There are parts for either manual focus (with a level/lock), and for support of several electronic focusers - I have used the zwo EAF one here (with eaf mounted and belt/gears, etc but I printed manual bits too - as unless I'm shooting mono with it, I don't see the need for an EAF tbh.

Very well designed, and fits it like a glove.

Lets you use with astro cameras or with DSLR - seen here on an asi224, and 135mm with my L-extreme on the end, guide mount above.

tripod screw on arm fits asiar pro, or whatever controller you are using, and all bottomed by a standard vixen mount.

Printed in PLA on a new printer I got this week (old one still ok, but not as clean and sharp prints as used to be).

 

[powerlord]

20 hours ago, nephilim said:

@daemon Thanks Steve, I've only just seen your reply & have literally just pressed the button on the WO one (It must be made of unicorn tears for the price) I very nearly emailed FLO to cancel but then realised it'll also fit my upcoming Sharpstar 100QII so its not all bad 🙂

ATB
Steve

I got this one for 10 quid:

https://www.ebay.co.uk/itm/184573856712

very good quality printout, works a treat - nice clear pattern.

stu

[nephilim]

24 minutes ago, powerlord said:

I got this one for 10 quid:

https://www.ebay.co.uk/itm/184573856712

very good quality printout, works a treat - nice clear pattern.

stu

Cheers but I've gone for the WO one as it'll fit both my Samyang & my upcoming 100mm refractor. I've had bad luck recently with random 3d printed gear. I overtightened a nylon screw on a printed tube ring for my Samyang lens & it cracked (good job it broke then rather than when nearly 1.5k worth of AP gear was entrusted to it) then my 3d printed BM for my lens somehow bent out of shape & is useless. I'm sticking with strictly non 3d printed kit now as the 'Buy cheap, buy twice' adage is certainly ringing true for me with those 😂

Edited August 18, 2021 by nephilim

[Simon Pepper]

My 135 turned up yesterday but I have realised I do t have any rings or dove tails can anyone recommend any and save me sifting through this thread please? I have both a zwo and a dslr so ideally work with both. Thanks 

[geordie85]

1 hour ago, Simon Pepper said:

My 135 turned up yesterday but I have realised I do t have any rings or dove tails can anyone recommend any and save me sifting through this thread please? I have both a zwo and a dslr so ideally work with both. Thanks 

I use one of these with some extra felt on the inside to make it a snug fit 

 

https://www.amazon.co.uk/Tripod-Collar-Mount-SIGMA-70-200mm/dp/B07DVKZBXG/ref=mp_s_a_1_3?dchild=1&keywords=lens+collar&qid=1629309904&sprefix=lens+coll&sr=8-3

[nephilim]

I use these which fit both the Lens & my ASI533, as @geordie85 mentions with their option, a strip of felt/ velcro is added for a snug fit. All my set up is mounted using PrimaluceLab gear, its expensive but very good quality & you can mix & match all the parts. https://www.firstlightoptics.com/tube-rings/primaluce-lab-80mm-plus-tube-rings-for-airy-apo65f.html

[nephilim]

I'll just add that the top plate on the camera side is a WO DSD 245 Plate & not PrimaluceLab

[nephilim]

And yet one more thing. ZWO do their own dedicated ring if thats all you want, they have several options which fit their range of cameras. https://www.firstlightoptics.com/zwo-accessories/zwo-holder-ring-for-asi-cooled-cameras-78mm-diameters.html

[Simon Pepper]

Solid selection of ideas here thank you very much 👌

[geeklee]

2 hours ago, Simon Pepper said:

My 135 turned up yesterday but I have realised I do t have any rings or dove tails can anyone recommend any and save me sifting through this thread please?

I still use the Astrokrakken rings on mine.  There are similar (and cheaper) options from Astrojolo too.  They do a job but perhaps not the greatest - maybe because they're trying to be so precise rather then give you a bit of leeway to use some felt!  My manual focuser ring started to have a bit of an issue with one screw getting stuck - a problem when you have to fine focus so carefully - but that started happening just as I moved to an EAF.

I've also seen the William Optics RedCat Mounting ring recommended too in this thread (with a suitable dovetail etc)

I totally understand the reservations around 3D printed parts and @nephilim sounded like he had a bit of a nightmare with his so understandably took a different path.  He's definitely spot on when he previously talked about a lot of money being supported by these solutions - so you need to be sure.

Edited August 18, 2021 by geeklee

[AstroFin]

Hello everyone!

Very interesting to see people using 3D printed mounting rings for the Samyang. Also @powerlord very nice shots using the L-eXtreme! I like your way of thinking outside the box regarding mounting the filter  

The night skies are finally getting dark again after a long summer, here's my first image of the season. 

• Samyang 135mm @f/2
• Canon 6Da, Astronomik CLS
• iOptron GEM 45
• 131x60sec
• Pixinsight, Starnet++

[RobST]

9 hours ago, AstroFin said:

Hello everyone!

Very interesting to see people using 3D printed mounting rings for the Samyang. Also @powerlord very nice shots using the L-eXtreme! I like your way of thinking outside the box regarding mounting the filter  

The night skies are finally getting dark again after a long summer, here's my first image of the season. 

• Samyang 135mm @f/2
• Canon 6Da, Astronomik CLS
• iOptron GEM 45
• 131x60sec
• Pixinsight, Starnet++

Fantastic image, i love how alot of us have been imaging the same subject so we can compare our efforts with each other 😀

[Chefgage]

18 hours ago, Simon Pepper said:

My 135 turned up yesterday but I have realised I do t have any rings or dove tails can anyone recommend any and save me sifting through this thread please? I have both a zwo and a dslr so ideally work with both. Thanks 

Although I do intend on obtaining some sort of ring setup I have just been using the 135mm lens connect just to the DSLR. So the DSLR is fitted on a dovetail but the samyang lens is just connected like a normal lens. I have not noticed any issues regards tilt etc when using it like this. Not ideal but it does work.

[Space Oddities]

20 hours ago, Simon Pepper said:

My 135 turned up yesterday but I have realised I do t have any rings or dove tails can anyone recommend any and save me sifting through this thread please? I have both a zwo and a dslr so ideally work with both. Thanks 

There are many ways indeed, to sum up what's been shared:

• Classic photography lens collars:
  • Plus: cheap, widely available, easy to use
  • Minus: you usually need to tweak it to add a millimeter or two. Also you can't fix anything on top (e.g. autoguider)
• William Optics RedCat 51 ring:
  • Plus: affordable (£39) and great quality, works out of the box, and you can add something on top. Good balance, since it holds the lens near its center of gravity. 
  • Minus: you can't change the aperture while the ring is holding the lens. But that's not a problem if you leave it always at the same aperture
• 3D Printed brackets (Astrokraken, Astrojolo, Astrodymium)
  • Plus: very lightweight, multiple rings allow a good grip on the lens, you can also change the aperture
  • Minus: can be a bit pricey, and it's plastic, so more risky than metal rings, rotating the lens might not be easy with some models
• Other types of rings:
  • Plus: very good quality, very secure (as nephilim showed), lots of mounting options for autoguider, focuser, etc.
  • Minus: very pricey (for Primaluce Lab rings, at least)

I tried the rings from Astrokraken and Astrojolo, but it didn't work out for me. The ring of my ZenithStar 61 also works well, but you can't add an autoguider on top, so it needs to be on the side and makes things complicated.

I finally ended up with the ring from William Optics, which is affordable and yet the best compromise between ease of use and mounting options, IMO. I even found that the 3D printed autofocus for the RedCat is also compatible with the Samyang (since they use the same ring system). Which means that I can install this on both my RedCat and the Samyang, all I need is to change the gear.

 

[Tomatobro]

This might have been posted elsewhere but for reference a GT2 2mm pitch tooth belt engages with the focus ring and allows for a Skywatcher DC focus motor to be used. Brackets to support the motor are need to be made to suit the mounting rings used

[RobST]

On 17/08/2021 at 18:38, nephilim said:

@daemon Thanks Steve, I've only just seen your reply & have literally just pressed the button on the WO one (It must be made of unicorn tears for the price) I very nearly emailed FLO to cancel but then realised it'll also fit my upcoming Sharpstar 100QII so its not all bad 🙂

ATB
Steve

Looking forward to your images with the sharpstar 😀 i was torn between that and an esprit 100, i went for the esprit in the end 😀 might be here by Christmas 😂

[geeklee]

1 hour ago, Space Oddities said:

I even found that the 3D printed autofocus for the RedCat is also compatible with the Samyang (since they use the same ring system). Which means that I can install this on both my RedCat and the Samyang, all I need is to change the gear.

Any news on when the official Samyang lens version might be arriving Pierre (if it still is)?  Or, do you have more details on the changes you made to support the RedCat version?  Thanks.

38 minutes ago, Tomatobro said:

GT2 2mm pitch tooth belt engages

I wondered about this @Tomatobro and what the engagement would be like for AF precision.  Honestly, I didn't think it would be suitable so designed and 3D printed a matching ring.  It's cool it can work and seeing you with it setup 👍  Is that an extra pulley to tighten the belt (just below the focus ring)?

[Tomatobro]

The idler pulley does allow for the tensioning of the belt but It was incorporated into the setup due to the choice of belt length being dictated by what I had in stock. A slightly shorter belt would have brought the tensioning adjustment within the slots on the SW motor.

The samyang lens focus barrel is a perfect match to the belt pitch.  The idler does increase the "belt wrap around" on the small motor pulley which means that the tension on the belt is hardly there.

Update.....I am planning to upgrade the SW dc motor to a stepper motor (along with the controller) so that Sharpcap V4.0 can do focusing between filter changes during an automated imaging run

Edited August 19, 2021 by Tomatobro
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