Imaging with the Samyang 135mm f2

[geordie85]

2 minutes ago, nephilim said:

@geeklee That makes sense. Ive just bought the Astro Essentials M48 adapter to make life easier although its on back order. Thanks again mate, this is my first foray into AP with a dedicated camera so i'd like to get everything right as best I can although i'm sure i'll have a fair few questions for this thread at a later date.

I'd like to add that when attaching the adapter make sure the screws are tight. When I first attached mine 1 screw was slightly looser than the rest (still tight, but not as tight) and this caused tilt. I had to dismantle whilst the camera was connected to my laptop and cooled and tighten it. 

All was well after this.

[nephilim]

5 minutes ago, geordie85 said:

I'd like to add that when attaching the adapter make sure the screws are tight. When I first attached mine 1 screw was slightly looser than the rest (still tight, but not as tight) and this caused tilt. I had to dismantle whilst the camera was connected to my laptop and cooled and tighten it. 

All was well after this.

@geordie85 Thanks for the info mate.

 

[Space Oddities]

On 10/01/2021 at 10:36, nephilim said:

I'm looking at getting the ZWOasi 533MC-Pro to go with my Samyang lens. Can anyone tell me if the M42-48 adapter that comes with the ZWO the correct one for the lens?

I posted a pic of my setup earlier, that might give you some ideas  

https://stargazerslounge.com/topic/333381-imaging-with-the-samyang-135mm-f2/page/17/?tab=comments#comment-3996625

I used the 44mm of back focus as follows (starting from the lens):

• M48 to T2 adapter TS Optics - 5mm
• TS 360° rotator (T2-T2), that also acts as a 2" filter holder - 19mm
• Spacer - 2mm
• ZWO T2 female to T2 female ring (sold with camera) - 11mm
• Camera - 6.5mm

That makes 43.5mm of back focus, with some room left to account for the filter inside the rotator  

I think adding a rotator in the imaging train can be useful, because of all the ways of mounting the lens I have seen so far, none of them made rotation very convenient...

A filter drawer could be very useful too, if you plan to use a dual narrowband or light pollution filter for instance. Alternatively, you can also screw a 1.25" filter directly on top of the sensor, with the right adapter from ZWO (I'm not sure it's included with the camera though). Less convenient if you need to switch filters often, but if you don't, it's by far the cheapest option  

Hope that helps! Welcome to the club  

Edited January 11, 2021 by Space Oddities

[nephilim]

6 hours ago, Space Oddities said:

I posted a pic of my setup earlier, that might give you some ideas  

https://stargazerslounge.com/topic/333381-imaging-with-the-samyang-135mm-f2/page/17/?tab=comments#comment-3996625

I used the 44mm of back focus as follows (starting from the lens):

• M48 to T2 adapter TS Optics - 5mm
• TS 360° rotator (T2-T2), that also acts as a 2" filter holder - 19mm
• Spacer - 2mm
• ZWO T2 female to T2 female ring (sold with camera) - 11mm
• Camera - 6.5mm

That makes 43.5mm of back focus, with some room left to account for the filter inside the rotator  

I think adding a rotator in the imaging train can be useful, because of all the ways of mounting the lens I have seen so far, none of them made rotation very convenient...

A filter drawer could be very useful too, if you plan to use a dual narrowband or light pollution filter for instance. Alternatively, you can also screw a 1.25" filter directly on top of the sensor, with the right adapter from ZWO (I'm not sure it's included with the camera though). Less convenient if you need to switch filters often, but if you don't, it's by far the cheapest option  

Hope that helps! Welcome to the club  

@Space Oddities Hi, thank you for that info, its a big help.

At the moment i'm looking at the easiest/ cheapest (although i've spent a small fortune so far getting my gear together) way of just being able to get up & running. A rotator is a good idea that i'll add at a later date.
Am I correct in thinking that the M48 ive just ordered is all I need just to get started ? https://www.firstlightoptics.com/adapters/astro-essentials-samyang-lens-to-m48-adapter.html   
I will be using 1.25" filters at some point but they can wait for now as I live in a Bortle 3 area. The following is what comes in the box when the camera arrives. 
 

• ASI533MC-Pro Camera
• Soft Padded Case
• T2-1.25" Nosepiece Adapter
• 1.25" Cap
• 2-metre USB 3.0 Cable
• USB 2.0 Short Cable x2
• T2-1.25" Adapter
• T2 Extender 21mm
• T2-M48 16.5mm Extender
• M42-M48 Adapter
• Spacers x3

[Space Oddities]

What's in the box is adapted to a scope with 55-56mm of back focus, so you won't be able to reach the 44mm required by the Canon lens. I think you have 2 options to get started:

Option 1

Provided you have the Astro Essentials adapter installed, you mount from the back of the lens:

1. ZWO's T2-M48 16.5mm Extender
2. ZWO's T2 female-T2 female adapter (the black ring attached to the camera) - 11mm
3. ASI533 - 6.5mm

That makes a total of 34mm, so you'll be missing 10mm in your imaging train. Perhaps you have a spacer already, otherwise you need to purchase one. Either T2-T2 or M48-M48, female to male.

I can recommend spacers from TS Optics. They have a lot of choice with all kinds of spacers and adapters, in a well organized section: https://www.teleskop-express.de/shop/index.php/cat/c10_adaptors.html

Option 2

While you're waiting for the Astro Essentials adapter (I'm not sure when they'll be in stock again!), you'll have to use a Canon bayonet adapter, like this one or this one. They work out of the box, you just need to connect the lens on one side and the camera with ZWO's 11mm ring on the other, and you're good to go  

There are other adapters out there, not by ZWO, like this one. But they have a different thickness. Although they work fine, you'll need to add spacers to get to 44mm... So not as out-of-the-box as ZWO's.

HTH!

Edited January 11, 2021 by Space Oddities

[geeklee]

4 minutes ago, Space Oddities said:

Option 1

Provided you have the Astro Essentials adapter installed, you mount from the back of the lens:

1. ZWO's T2-M48 16.5mm Extender
2. ZWO's T2 female-T2 female adapter (the black ring attached to the camera) - 11mm
3. ASI533 - 6.5mm

That makes a total of 34mm, so you'll be missing 10mm in your imaging train. Perhaps you have a spacer already, otherwise you need to purchase one. Either T2-T2 or M48-M48, female to male.

Good to see another person coming to the same conclusion.  I was concerned I'd missed some way to make it work out the box yesterday  

 

Edited January 11, 2021 by geeklee

[nephilim]

3 minutes ago, Space Oddities said:

What's in the box is adapted to a scope with 55-56mm of back focus, so you won't be able to reach the 44mm required by the Canon lens. I think you have 2 options to get started:

Option 1

Provided you have the Astro Essentials adapter installed, you mount from the back of the lens:

1. ZWO's T2-M48 16.5mm Extender
2. ZWO's T2 female-T2 female adapter (the black ring attached to the camera) - 11mm
3. ASI533 - 6.5mm

That makes a total of 34mm, so you'll be missing 10mm in your imaging train. Perhaps you have a spacer already, otherwise you need to purchase one. Either T2-T2 or M48-M48, female to male.

I can recommend spacers from TS Optics. They have a lot of choice with all kinds of spacers and adapters, in a well organized section: https://www.teleskop-express.de/shop/index.php/cat/c10_adaptors.html

Option 2

While you're waiting for the Astro Essentials adapter (I'm not sure when they'll be in stock again!), you'll have to use a Canon bayonet adapter, like this one or this one. They work out of the box, you just need to connect the lens on one side and the camera with ZWO's 11mm ring on the other, and you're good to go  

There are other adapters out there, not by ZWO, like this one. But they have a different thickness. So that might work, but you'll need to add spacers to get to 44mm... 

HTH!

@Space Oddities Thats great thankyou. 
 

I'm used to just a DSLR on a scope so all this is pretty new to me. I've basically built my AP rig from the ground up over the last 4 months & now just have the camera & lens mounting options left to buy although thats still a couple of months away yet. I'm using my time to gain as much info as I can.

The Astro Essentials adapter should arrive by the end of the month along with my ASIair Pro that ive ordered from FLO.
My initial set up was just going to be Asi 533 & the Skywatcher 80ED but after reading the Samyang thread I decided I loved the images that set up was producing.
I'm looking at mounting the lens on this https://www.wega-telescopes.de/shop/Rohrschellen-passend-für-Samyang-135mm-F2-Objektiv-inkl-Sucherbasis-3D-Druck-p258368766 My main concern is that I bought the Evoguide 50ED ( with the Asi 120MM-S as guide camera) to use as my guide scope on my original set up & now i'm thinking it may not be suitable going on top of the lens using the above  bracket but I cant think of another option really.
 

ATB

Steve

[fireballxl5]

A shot of M45, the Pleiades open star cluster, captured from the back garden on 16th Oct last year using my mobile rig.

135mm Samyang lens at f/2 with ASI071MC Pro camera and IDAS D2 LPF on SW AZ-GTi mount, all powered using ASIair Pro.

42x180s, so just over 2 hours total exposure.

[geeklee]

A first try with the L-eNhance filter on the ASI533 and Samyang 135, wide open at F2.  I wanted to test the signal at F2 and F2.8 but this was a bit of a fire and forget mosaic that I set off on Saturday evening so I didn't get a chance.  The L-eNhance has quite a wide band pass, but I'm not sure if I was still being impacted by loss of signal due to shifting at this speed.

Anyone else using this filter at F2?  I see a variety of filter combinations on the mono cameras - from a typical Baader/ZWO Ha to wider Astronmiks and even the high speed Baaders.  I'd be interested in any opinions on this - especially at F2.

Anyway... this is a 2 panel mosaic with a wide overlap.  Around 1h 45min per panel (180s subs).

[geeklee]

The image above was a mixed bag with intermittent clouds, but the worst subs were removed.  I just found 14 subs (each 180s, also with ASI533 and L-eNhance) I took in another part of the sky - Heart and Soul in Cassiopeia - before I gave up for the evening.  Hopefully this gives some hope that even with a cloud dodging effort of 42 minutes, this lens can still produce... something.  I know, it's not great, nor any sort of finished project but it's fun in between the bigger stuff.

Most of the subs had cloud of some sort if I remember right and a few might even include a telephone wire!  Examples:

Very quick run through PixInsight after being pre-processed in APP.

Clear skies.

Edited January 20, 2021 by geeklee
Added nebula info

[Space Oddities]

That's a great result Lee! This lens and this camera seem to be the perfect companions for quick grab & go imaging  

I'm super jealous, as I haven't been able to image since October. Nothing but clouds here in Bavaria, and a curfew is in place since mid-December, which means I can't go out anyway at night...  

My Samyang is looking at me and I can feel the despair in his big, bulbous front element!  

[geeklee]

3 hours ago, Space Oddities said:

This lens and this camera seem to be the perfect companions for quick grab & go imaging  

It really is.  I'm mulling over options for always having it running while doing other projects (maximise that clear sky!).  As always, most options = varying £  

3 hours ago, Space Oddities said:

I'm super jealous, as I haven't been able to image since October. Nothing but clouds here in Bavaria

 It's definitely been bad here but there's been the occasional glimmer here and there.  Clear outside had me falling off my seat yesterday as it predicted Sat, Sun and Mon evening as clear!  That's returned to normal now of course and mainly red  

3 hours ago, Space Oddities said:

I can feel the despair in his big, bulbous front element!

What a great description   Just convince him he'll get his day and to hang in there!

[Space Oddities]

A lot of people use a little mount on the side, like a Star Adventurer or AZ-GTi. A cheap way to maximize the cloud-free time indeed!  

[geeklee]

A last batch of scruffy data from the early morning at the start of the week.  Targets for a 135mm lens after midnight are getting challenging with the view from my back garden so I'll need to spend some time investigating further if I'm running this rig during the early hours.

Here's a wide field look at the Leo triplet and a 1:1 view of just the triplet.  In the wide view, click through and look far left for NGC3596, top for NGC3593 and far right for NGC3666.  2 hours, 30s subs with the ASI533 and Samyang 135 @ F2.

 

Edited January 21, 2021 by geeklee

[festoon]

Managed to get 1 hour of data of M31 tonight between dusk and the rain. Imaged at f2 with an ASI224MC Cool OSC camera, and mounted on an AZ-Gti with no guiding. 352 x 10s exposures at unity gain.

Stacked in DSS, Colour correction and gradient removal in Siril, Curves adjusted in Gimp, and final touch ups in Startools.

 

[fireballxl5]

My latest Samyang 135mm f/2 process, M31 from last Nov/Dec 2020. Integration of 88x180s subs captured over two nights with an ASI071MC Pro and IDAS D2 LPF in the suburbs. Mounted on a guided AZ-GTi, all controlled by AAP.

Processed using MaxImDL (calibration, alignment & stacking), PixInsight (bulk of image processing), with final tweaks in Photoshop CS3.

[FenlandPaul]

I’ve been super-impressed with this lens. Here’s a couple of images with a modified Canon 450D (Orion) and Canon 6D (Pleiades) over the last few weeks. I’m not very experienced in deep sky (although long-time observer) but I found the Samyang a delight and very forgiving to use.

 

[Richie092]

I think the 135 is going to be my next purchase after what I have read and seen on this thread.

Does anyone know if this holder -

https://www.firstlightoptics.com/tube-rings/wo_zs61_cat_handle_kit_rd.html

 

Will fit and do the job? Then I can share my W/O guide scope.

 

TIA

 

Richie

[Richie092]

On 09/01/2021 at 18:52, Stardust said:

First light this week for the Samyang on a new ZWO533, misty night but had to get out there. 

 

Love this. Is it cropped at all? Did you use an IR/UV filter at all?

[carastro]

The purchase of the Samyang 135mm F2 lens has kept me sane over the last year of lockdowns and being unable to go to my darker Bortle 4  location (went once) over the last year, but I have now run out of suitable images I can do from home at Bortle 8, but there are a load of broadband targets I want to do once I can get back to camp. 

These are the ones I haven't posted before:

I even purchased myself a 2nd Atik460EX as I was constantly moving the camera from the Samyang to the Telescope, so now I have a dedicated one for the Samyang lens. 

Heart and Soul: 

1 1/2 hours Hubble Palette

 

California Nebula 4 1/2 hours

Spaghetti Nebula HaRGB (tough from Bortle 😎

4 hours

My latest one 

Barnard's Loop with the Bogeyman and M78

2h 50mins (a struggle with a tree in the way for several hours)

Edited February 7, 2021 by carastro

[carastro]

Here's one more I took back in the summer I have been sitting on.

This was done at my Astro camp Bortle 4 on the only occasion I managed to get there this year. 

M45 LRGB 3 hours.

Edited February 7, 2021 by carastro

[Stardust]

22 hours ago, Richie092 said:

Love this. Is it cropped at all? Did you use an IR/UV filter at all?

Yes it is quite a good crop and I used an Optolong L- enhance filter on loan from a friend

[AnonymousAnimosity]

Today I finally picked up the WO redcat ring, sadly it clashes with my camera so rotation is impossible. I am not sure whether I should try to file it or just return it and buy something else.

 

 

Edited February 11, 2021 by AnonymousAnimosity

[Richie092]

I suppose it depends on what is going on top of the ring. If you are mounting a guide camera on it then it probably won't be worth it. If it is staying as it is then it will only need a tiny bit taken off, personally I would file it.

[AnonymousAnimosity]

18 minutes ago, Richie092 said:

I suppose it depends on what is going on top of the ring. If you are mounting a guide camera on it then it probably won't be worth it. If it is staying as it is then it will only need a tiny bit taken off, personally I would file it.

I would like to mount on this 30mm guidescope, it looks like it should fit even if I file the rear of the base.

Edited February 11, 2021 by AnonymousAnimosity