Rokinon 135mm F/2 Astrophotography Lens: Review And First Build

[@hdguppies]

@5:36 I tried same thing. The nifty fifty needs power from the camera to focus. You can pull on the optical tube and force it to focus but that is hit or miss. I bought a 50mm 1.7 manual lens from Aiexpress to use on the astro-cam. I'll say it is ALMOST as good as the real nifty fifty.

[@AstroDanno]

I wasted a night trying to get it to work. I think I am going to do the same thing, and buy a manual 50mm lens for the dedicated cameras. What brand lens did you get?

[@danielslatford7795]

Rokinon for some strange reason rebranded their lenses to Samyang for the European market. So absolutely no difference between the two lenses

[@AstroDanno]

They look identical except for the branding, but the Samyang lenses can be found for a bit cheaper.

[@KevinRudd-w8s]

Samyang and Rokinon are the same, for some reason different brand names are used in different areas of the world, here in the UK they use the Samyang brand name, in North America they go with Rokinon. I've heard that it can bea bit hit and miss with the quality control but I was lucky I guess because mine has been great. I usually shoot at f2.8 ,~ 3 which seems to give good results. I used to set mine up similar to you but ended up buying the Astro Dynion kit which I find superior, I use it with an EAF, ASI mini guider and an ASIair mini and a Star Adventurer GTi. When I first bought this lens I used it with the original Star Adventurer tracking mount and a Canon 600D ( think that's a Rebel 3ti or similar in the States) and that also gave good results. I agree that this is a good lens to get started in wide field astrophotography.

[@AstroDanno]

@@KevinRudd-w8s I’ve got mine ready for first light with the Astrodymium cradle, just waiting on a clear night so I can get the guide cam focused, and the Focuser all set up. I’m ready for Fall, cooler and longer nights!

[@thinkable3D]

Have you ever seen the HyperPod 135 mounting system for this lens?

[@AstroDanno]

I think I saw that on Etsy. It looks pretty good as well.

[@michaelclancy7874]

No back focus issues? I have a ASI 183MC pro I am attaching to a Rokinon 135mm. Just pop it on? Thanks for taking the time to make this video

[@AstroDanno]

@@michaelclancy7874 I’ve used the 533 and the 2600mc pro with this lens, and I’ve had no issues with back focus. I use the ZWO canon EF lens adapter, because my Rokinon fits Canon camera bodies.

[@jeromeThailande]

Back or front focus is only about autofocus ,not manual focus lenses, as far as I know

[@AstroDanno]

@@jeromeThailande you have to have the right adapter for correct back focus if using a dedicated camera. I put a filter wheel on this rig and couldn’t reach focus because I forgot to take the housing ring off. I took that off and was able to reach focus.

[@jeromeThailande]

@@AstroDanno a camera for sale without lens or adapter is a joke

[@AstroDanno]

@@jeromeThailande welcome to this hobby! 😂

[@ridearocket]

Did you have to adjust the infinite focus point? I know some users of the Rokinon / samyang 135 had to adjust the hard stop to achieve infinite focus.

[@AstroDanno]

I didn’t have to adjust mine. Infinity is close to the very end of travel on the focus ring, but I can still focus with it.

[@alejandrohenriquez7316]

Hello. I also have a Rokinon 135 mm with the two 2600 MC, with a filter I get the focus easily, but aye I wanted to use it without filters and I couldn't get the focus. Could you tell me or rather help me how I can solve this situation. I'm waiting. Thank you and best regards,

[@AstroDanno]

@@alejandrohenriquez7316 are you using a filter wheel or filter drawer? I don’t think I’ve used mine without a filter, but I can usually reach focus. You may have the “infinity focus” issue. I think @NebulaPhotos has a video on adjusting the infinity focus on the Rokinon/Samyang 135.

[@alejandrohenriquez7316]

@AstroDanno Thanks!

[@alejandrohenriquez7316]

@AstroDanno filter drawer

[@AstroDanno]

@@alejandrohenriquez7316 your lens may not be able to reach focus. Mine is very close to the end. It can be adjusted but I didn’t have to do it.

[@arjundhannyify]

I see the az gti to your left... do you love it or hate it? 😅

[@AstroDanno]

@@arjundhannyify I’m having mixed feelings about it lately. After the last ASIair update, the guiding has been doing some odd things. Guiding going off the charts, numbers not consistent. I don’t think it’s the mount backlash or anything like that. I think it’s the ASIair mostly, because other users are reporting issues as well.

[@AstroDanno]

@@arjundhannyify I was still able to get 5 minute subs on my last image, so I don’t hate it. It does well with small rigs most of the time.

[@captaincook6666]

Hi mate. Im using this lens with ha filter to map the sky. Getting amazing results in bortle 7. I have a vid out on wknd if youd like to see.

[@AstroDanno]

Cool, I’ll check it out!

[@captaincook6666]

@@AstroDanno it's out now (short and full video)

[@seriousbassface]

I wonder what the odds are of getting a good or even decent copy of this lens. I'm personally 0/2. Is it like 2 out of 10? 4 out of 10? I kind of want to try again or buy a used one that I know is good but definitely don't want to keep getting crap versions.

[@AstroDanno]

@@seriousbassface were you able to return them? Maybe try a lens rental place and then purchase once you get a good copy. I just tried my Rokinon 24mm, and the stars are pretty bad wide open. I’ll have to do some more tests with it, but I’m sure I’m past the return window.

[@seriousbassface]

@@AstroDanno That's a great idea! I'll have to look into some rental places that let you purchase after. Yes, luckily I was able to return them, stars were bad until I stopped it down to about F8 or 9 or something lol. It's a shame because in the center I see the hype, it did look great/super sharp there. Corners on even a M4/3 were very very bad though, which blurX surprisingly fixed but I didn't want to settle for terrible. So my search continues, I'll try your advice!

[@AstroDanno]

@ I’ve had a couple of friends rent and then buy. I shoot at f/4 with my 135, and that helps. This is my second one, I shot wide open with my first one, and I think it was better. I unfortunately dropped it one night when a screw wasn’t tightened down on my Skyguider pro. 😖

[@seriousbassface]

@@AstroDanno ooooooof that's rough, well at least it wasn't a Takahashi! lol Only downside with rental though is then I'm paying the rental price if it's still not a good copy as opposed to buying and returning/exchanging. B&H was nice and let me exchange one and ultimately return the replacement. I just didn't want to keep playing the lottery and sending them back and forth.

[@AstroDanno]

@ it is a game of chance. My Rokinon 14mm is good, the 24mm… not so much. I’ll have to shoot with it again to see if there is a sweet spot.

[@AmatureAstronomer]

Interesting.

[@AstroDanno]

It’s a great wide-field lens if you don’t have one!

[@mikehardy8247]

Love my Rokinon 135mm. Originally paired it with Rebel T7i, on Original SA, or MSM. Once I bought an ASI533MC Pro, I bought the ZWO filter drawer as you use. Paired with the THINKABLE CREATIONS Hyperpod is awsome. This allows EAF, ASIAIR to pair perfectly. Do you think Rho OPHIUCHI will image well, or is this too tight?

[@AstroDanno]

@@mikehardy8247 it just barely fits in the FOV with the 533, hoping I can try it with the 2600 this summer.

[@mikehardy8247]

In Wisconsin it's pretty low in southern sky. Missed it last summer. Maybe this year. When zwo has there Dec sale, a 2600 is on my Xmas list.

[@AstroDanno]

@@mikehardy8247 they had dropped the price $500 from when I bought mine. Not sure if it’s still there, but that’s a pretty good deal.