Jump to content

Banner.jpg.b83b14cd4142fe10848741bb2a14c66b.jpg

Samyang 135mm f2 - First light and impressions...

Uranium235

By Uranium235
in Imaging - Deep Sky

Recommended Posts

Uranium235

Uranium235

Posted
Posted

I've been waiting a few days to test this little jobbie out, but last Friday night was a good one for testing out the new bit of glass.

Priced at £358 this particular lens has been making a few waves and I thought it was worth checking out to see what all the fuss is about. Tried it on the DSLR first, nice... a lot of weight to it - but not really a lens for action shots (manual focus only). But, eventually I cobbled together the adaptors from my bits box in order to mount the CCD on it.

What I did find, is that the EOS - M48 adaptor Im using had a little play between the lens base and the adaptor (not just rotational as you often get) - but no time to sort out a guidescope ring to support the lens... so I just chucked it all out there and hoped for the best (however, a supporting ring is now in place). 

Next thing I found to be different was focusing..... at f2 the focal plane is very narrow indeed, the adjustments were so small that it looks like youve hardly moved it.... just the lightest of touch required.I did have a worry about whether using normal Baader NB filters at f2 would damage the image... seems not, but im pretty certain that a dedicated highspeed filter would be far more efficient (and keep the stars down a little).

So.... how is its flatness? Well... when properly held in place, its nothing short of remarkable what has been achieved at this price - most lenses usually fall over when wide open... but not this one! It might be worth trying at f2.8 to see if it better suits the filter - but im loathed to add apeture blade diffraction spikes to an image.

For this image I have layered in the Rosette from the Star71 version to make it a little more snappy. Also, I had to throw a few subs because the lens dewed over - might be due to a faulty connetion on the dew strap (it was stone cold when I checked it).

Didnt want to clip the background either as there are a few background structures appearing.

 

14x900 (Ha)

Samyang 135mm f2, Atik 383L+, NEQ6

 

Thanks for looking :) 

31789847382_66db1ccfd1_k.jpg

Link to comment
Share on other sites
  • Replies 25
  • Created
  • Last Reply
JohnC64

JohnC64

Posted
Posted

yes it looks very good indeed.  You may want to have a look at these for making your focusing easier http://www.teleskop-express.de/shop/product_info.php/info/p3286_Microfocuser-and-focus-lock-fuer-camera-lenses-up-to-D-135mm.html

They connect to the outside of the lens and let you micro adjust your focus ring.  

The other trick to do instead of stepping down the lens is to cut some concentric rings and drop them over the front of the lens to allow you to step down without having the blade spikes

It does look an impressive lens if that image is anything to go by
Cheers John
 

Link to comment
Share on other sites
Uranium235

Uranium235

Posted
  • Author
Posted
5 minutes ago, Rudeviewer said:

Super nice widefield!  I have a 383l+ as well, how do you put a HA filter onto this?  I have been wanting so setup a super widefield rig for a bit now, but wasn't sure how to do it with the Atik 383l+.

Getting the Ha filter in there was a bit tricky. I had to mount a short filter holder inside the TS EOS - M48 adaptor. The trouble with the 383 is its ridiculous backspace requirement of 17.5mm, that makes it jolly hard to insert a filter wheel or drawer into the equasion. The only downside with the current arrangement is that filter changes are not easy.

Link to comment
Share on other sites
Rudeviewer

Rudeviewer

Posted
Posted
Just now, Uranium235 said:

Getting the Ha filter in there was a bit tricky. I had to mount a short filter holder inside the TS EOS - M48 adaptor. The trouble with the 383 is its ridiculous backspace requirement of 17.5mm, that makes it jolly hard to insert a filter wheel or drawer into the equasion. The only downside with the current arrangement is that filter changes are not easy.

Are you using the Geoptik canon adapter then?  Yeah the backspacing has given me problems from day one trying to match equipment with it.  

Link to comment
Share on other sites
Uranium235

Uranium235

Posted
  • Author
Posted
2 hours ago, ollypenrice said:

Stonk, that is sumptuous. Seriously impressive. I used a Samyang 85 for a while, also very good, but my CCD pixels were too big for it. You could do mind blowing NB super-mosaics with that. As I rather suspect you will!!

Olly

Yes, I do wish I had a camera with smaller pixels (3.6 would be nice), but it seems alright with the 383 - its never going to set the world alight with fine detail but its great for the "bigger picture" so we can see where popular objects sit in context with each other in the night sky.

I managed to get out for 90min earlier before the fog rolled in to see how it performs with a luminance filter. I generally dont go looking for dark nebs at my home location (just too darn hard!) - but I thought it worth a stab at f2.

Exposures are limited to 4min becuase of background levels (the histo was starting 9000 from the left... as high as I dare), but for such a limited run I made some decent headway into the dust.... oh if only I had this at a dark site! :)

 

A random patch of Taurus: LDN1532 (and a few other LDNs lurking in-shot)

24x240 (Lum)

31829602491_a81ee20ef1_k.jpg

Link to comment
Share on other sites
ollypenrice

ollypenrice

Posted
Posted
23 minutes ago, Uranium235 said:

Yes, I do wish I had a camera with smaller pixels (3.6 would be nice), but it seems alright with the 383 - its never going to set the world alight with fine detail but its great for the "bigger picture" so we can see where popular objects sit in context with each other in the night sky.

I managed to get out for 90min earlier before the fog rolled in to see how it performs with a luminance filter. I generally dont go looking for dark nebs at my home location (just too darn hard!) - but I thought it worth a stab at f2.

Exposures are limited to 4min becuase of background levels (the histo was starting 9000 from the left... as high as I dare), but for such a limited run I made some decent headway into the dust.... oh if only I had this at a dark site! :)

 

A random patch of Taurus: LDN1532 (and a few other LDNs lurking in-shot)

24x240 (Lum)

31829602491_a81ee20ef1_k.jpg

That really is tight for luminance at short FL/F2. Amazing, in fact.

Olly

Link to comment
Share on other sites
PatrickGilliland

PatrickGilliland

Posted
Posted

Told you they where good :) Nice to see the proof though - nothing worse they it not happening after I have praised the lens!

Images look spot on - for me an autofocus is the next option.  As you point out you are down to tiny adjustments and if you are off by a similar amount you may find some bloat saving even on these images which look tight!

Nice work.

Paddy

Link to comment
Share on other sites
Uranium235

Uranium235

Posted
  • Author
Posted
4 hours ago, StuartJPP said:

Very nice write-up. I bought one of these a couple of months ago but I have yet to use it properly yet...looks like I need to get out with it!

You should mate, its alright @ f2 up to APS-C, but I reckon for full frame you need to drop it to f2.8... hardly a poke in the eye with a burnt stick cos thats still pretty rapid :)

Link to comment
Share on other sites
  • 10 months later...
Jkulin

Jkulin

Posted
Posted

That is a seriously sharp image, very nice.

I have been using a Samyang 14mm for my wide field and I am very impressed.

Geoptik do an adapter so that you can use either a Canon or Nikon lens, but I believe that you can use 2" filters with the Canon but only 1.25" with the Nikon, it would be interesting to see if you could get back focus with the Geoptik

Link to comment
Share on other sites
Uranium235

Uranium235

Posted
  • Author
Posted
16 hours ago, Jkulin said:

That is a seriously sharp image, very nice.

I have been using a Samyang 14mm for my wide field and I am very impressed.

Geoptik do an adapter so that you can use either a Canon or Nikon lens, but I believe that you can use 2" filters with the Canon but only 1.25" with the Nikon, it would be interesting to see if you could get back focus with the Geoptik

I tried the Geoptik, but I found it far too fiddly to get a 2" in there.

However, this thread is quite old and I have since sold my Samyang in order to fund a house move. But sure enough, once funds become available I'll be getting another ;)  (or two)

Link to comment
Share on other sites
geordie85

geordie85

Posted
Posted
17 hours ago, Uranium235 said:

I tried the Geoptik, but I found it far too fiddly to get a 2" in there.

However, this thread is quite old and I have since sold my Samyang in order to fund a house move. But sure enough, once funds become available I'll be getting another ;)  (or two)

Do you know if there's any way to use unmounted 36mm filters with this adapter?  

I've just recently got this lens and want to use it with my atik 383l but really don't fancy shelling out for a set of 2" filters. Also can't use my SX filter wheel due to too much back focus.

Also have you got any ideas for quick filter changes?

Link to comment
Share on other sites
Uranium235

Uranium235

Posted
  • Author
Posted
6 hours ago, geordie85 said:

Do you know if there's any way to use unmounted 36mm filters with this adapter?  

I've just recently got this lens and want to use it with my atik 383l but really don't fancy shelling out for a set of 2" filters. Also can't use my SX filter wheel due to too much back focus.

Also have you got any ideas for quick filter changes?

Unfortunately not for 36mm, its possible for 2" - but I cant think of a method for 36mm. Not unless there is some sort of adaptor to convert 36mm unmounted to 2" mounted.

But even for 2", I ended up making my own custom adaptor. However, I think ZWO make an EOS - to T2 adaptor:

https://www.firstlightoptics.com/zwo-accessories/zwo-eos-lens-adapter-for-efw-mini-asi1600.html

No ideas on its thickness though, you might have to research that.

Link to comment
Share on other sites
Uranium235

Uranium235

Posted
  • Author
Posted
14 minutes ago, Allinthehead said:

That's 17.5mm. Not sure I'd go with it as the one i have has a bit of movement causing tilt depending on where I'm pointing.

Thats where you might have to insert small metal shims under the springs in the adaptor - to force them out a bit more. I had to do it to my exisiting adaptor, but after doing it the fit was quite snug - but it still required some sort of support with a guidescope ring. Any sort of slop at f2 is quite severely punished.

Look at the spring @ 12 o'clock in this pic, see the bit of aluminium I inserted?

IMG_2238.JPG

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.