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OVNI-B With More Camera Lenses in the City

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#1 Mort H

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Posted 29 September 2021 - 10:05 PM

I have to confess, when I decided to take the plunge into NV I knew you could attach a camera lens, but I sort of shrugged that feature off as "oh that's nice but I probably won't actually do that much".  Well...last night was my second night now using camera lenses...and man I LIKE this way of observing.  Time will tell, but going forward I might actually end up logging more observing time with camera lenses than with my telescope!

 

Last week, I tried out several Canon camera lenses that I already owned for regular photography...35mm, 50mm, 105mm, 135mm, 200mm, nice views in them all.  I have accumulated quite a few Canon lenses over the years, due to a variety of subject matter, and last night (the first clear night in a week) I decided it was time to play around with a few more of them!

 

I was observing from home, 3 miles from the Grand Rapids (Michigan) city center, Bortle 6 skies according to Clear Outside app.  I didn't get started until after midnight due to obligations earlier in the evening, and a pretty bright moon rose shortly after I started, I would have to deal with that all night.

 

Last week my 200mm f/2 lens was giving great views at 7.4x, 5.4 degree FOV.  This week I wanted to go higher in power.  I have both the 1.4x and 2x Canon teleconverters (TC's).  The 1.4x turns my 200mm f/2L lens into a 280mm f/2.8 (10x, 3.8 degree FOV).  I also have the Canon 400mm f/4 DO, and I wanted to try that out with no TC (15x, 2.7 degree FOV), with the 1.4x which makes it a 560mm f/5.6 (21x, 1.9 degree FOV), and with the 2x which makes it an 800mm f/8 (30x, 1.35 degree FOV).  Both the 200mm f/2L and 400mm f/4 DO take the TC's very well, and I've used the 400mm with 1.4x and 2x with great results for birds and wildlife.  How about astronomy now!

 

10-30x are high enough powers -- and these lenses are heavy enough lenses -- where it's nice to support the lens instead of handholding it, so I grabbed my good solid tripod with fluid head.  Only problem of course is trying to look towards the zenith!  I could just choose to look at stuff that's not so high in the sky, but there was a lot of cool stuff pretty much overhead!  Well it turns out my trusty adjustable-height observing chair works pretty well with the tripod...in addition to allowing you to be seated, it allows you to lean back somewhat, which greatly helps in looking closer to the zenith.  Here's a photo of the rig, showing the 400mm f/4 with 2x TC:

 

CN-026.JPG

 

Very busy background in this cell phone pic (not much of a photographer am I)!  Here's a closer up photo, you can sort of see my Kendrick heaters wrapped around the OVNI-B eyepieces, with the white heater controller at left velcro'd to the tripod.  Eyepiece fogging is a HUGE problem in Michigan, dew heaters have been a life-saver for many years for me, I don't (can't) observe without heaters in Michigan.  The camera lens hood also helps a lot in keeping dew off the front of the lens (and I try not to leave the lens pointing straight up if I take a break).  I envy those of you in dry and warmer climates!

 

CN-027.JPG

 

The tripod rig above with observing chair works pretty good, all things considered!  But let me also run through my other rigs for last night's session, after which I'll list all the cool stuff I was able to see during the course of the night!

 

So after quite a while of using the tripod rig to look quite high in the sky, I did start developing a mild case of what birders call "warbler neck"!  As an alternative, I have this totally awesome binocular mount that I've used and loved for a good many years.  It's an Oberwerk binocular mirror mount (long since out of production, a shame), and it's just the cat's meow for my 25x100 binoculars.  It also works great with smaller binoculars (and I own several), the mount is adjustable.  (Did I mention I LOVE binoculars!)  Years ago I enclosed the mirror mount in a home-made combination light shroud / dew shield (total hack job but hey it's held up well)!  As luck would have it, removing the binocular attachment post and replacing it with the tripod mount ring for my Canon 200mm f/2.8L lens fits the mirror mount to a "T", it's just incredibly lucky/awesome!  The 200mm f/2.8L is one of Canon's most unsung lenses, it doesn't get much love, but it's small and light (and sharp), and wouldn't you know it fits perfectly on my mirror mount where a bigger lens would not.  Here's a few photos (in this first one there's a black TV in the background, that's not part of it!):

 

CN-025.JPG

 

Different angle, you can see Kendrick heaters on the OVNI-B eyepieces (there is also a heater on the back of the mirror itself, though it's hard to see in the photos):

 

CN-022.JPG

 

You can see the mirror hiding back in there on this photo:

 

CN-021.JPG

 

Closer view of the mirror and 200mm f/2.8L lens (with 2x TC installed, I can use it with 1.4x TC as well, or with no TC):

 

CN-023.JPG

 

Looking down the top dew sheild:

 

CN-024.JPG

 

Probably one of the weirdest-looking binocular mount setups the world has ever seen!  (Somehow that fits me.)  BUT...the beauty of it is...it's an absolute joy to use, extremely comfortable (with my beloved adjustable-height observing chair) to view pretty much anywhere in the sky, especially high in the sky, even at the zenith!

 

I'm almost to the list of cool stuff I saw this night!  But there was one more setup I used this night, it was also a lens I had not tried out before, and for this one I just went handheld, it's a cute little lightweight (and sharp!) Canon 85mm f/1.8, also a great lens that used to be a staple of many photographers kits, but is now older and not very sexy and consequently gets little love these days.  But it's a great lens.  It was really fun handholding this, I actually had this little rig in operation both early and late in the night, I had to come back to it, it was so cool.  Here's a photo, isn't it cute:

 

CN-020.JPG

 

So WHAT could I see with all this crazy gear?  Here's my list from this session:

 

1)  California Nebula!!!  I kept coming back to this ALL NIGHT LONG with EVERY lens, it was so good.  Just insane that I had never seen it (except in pictures) prior to NV, and now I can't believe how bright and easy this thing is with NV, it's like one of the easiest things in the sky!  It looks great at low power, and at higher power you just feel like you've been transported into space and are INSIDE it!

 

2)  The Pleiades.  What, who needs NV to see the Pleiades?  Nobody I guess, but I have to say it looks pretty darn good with NV!

 

3)  Andromeda Galaxy.  Again, bright naked-eye object, who needs NV?  Well, first of all, I never really thought M-31 was all that uber bright, due to its size.  But with NV, it's REALLY bright.  AND I can see some structure (with higher power) that I never saw without NV.  So once again I'm learning that NV can still benefit "ordinary" objects that don't "require" NV.  NV isn't just reserved for the impossible targets.

 

4)  I had to head over to Cygnus while there was still time, my view of the western sky is largely blocked here at my house, and Cygnus was slipping away from me.  The Veil was already too far west, but Holy Smokes the Gamma Cygni region...it's just sick!  Mind-blowing.  I already gushed over it in a previous post, I'm repeating myself, but man it's good.  North American and Pelican, along with Sh2-119 (the Clamshell I guess they call it?) were all looking very good as well.

 

5)  Another sick region of the sky for nebulae is Cassiopeia and Cepheus.  I got a taste of it before, but last night I was coming back for more!  The Pacman is a good jumping-off point, then to Ced 214, NGC 7822, NGC 896, the Heart and Embryo.  Fantastic!

 

6)  Slide a very short ways over to Cepheus, this is where I followed -- several times during the night with different powers -- a large string of 6 objects in a large arcing line, in order they were:

- IC 1396 (contains Elephant Trunk) just S of Hershel's Garnet Star, this was my starting point for the string (arc) of objects.

- Lion Nebula (Sh2-132).

- Wizard Nebula (Sh2-142).

- Lobster Claw a.k.a. Californietto Nebula (Sh2-157).

- Bubble Nebula (NGC 7635).

- NGC 7538.

This was a really cool line/arc of objects, and low power helped to establish the sequence, but once you know how it goes, it can be followed pretty easily in higher power camera lenses too.

 

7)  By this time it was getting late, and Orion was rising!  So of course I had to feast on the Orion Nebula, who could ever get tired of it?  Normally that's all I get, but THIS time I had NV, so there was more:  the Flame and Orion's Dagger containing the Horsehead.  I wasn't really making out the Horsehead, I think my power was too low, but the Dagger was easy, as was the Flame.

 

8)  From Orion, I slid over to the Rosette, then the Monkey Head, Lower's Nebula, and Sh2-273 (Christmas Tree Cluster region).  When viewing the Monkey Head, I was super careful not to look at the Moon, which was JUST outside the FOV...I could see at the edge of the FOV this incredible brightness, the Moon must have been just a gnat's eyelash away, yikes!  I was actually worried that if I looked at the Moon then the OVNI-B might vaporize and/or my head might explode or something!  Just mind-numbing that I'm observing a nebulae under such conditions!  I also tried for the Jellyfish, but I couldn't get there, the Moon was like RIGHT there if I moved ANY farther over!

 

By the way, for most of the night my favorite filter seemed to be the 6.5nm, it got the most use by far.  Funny that just last week I was preferring the 3.5nm to the 6.5nm.  This week it was the opposite.  Temperature and humidity were definitely different, maybe sky conditions/transparency had something to do with it.  Last week I was using all very fast lenses (f/1.2, f/1.4, f/1.4, f/2, f/2), whereas this week I was using almost exclusively slow lenses due in part to the TC's (f/2.8, f/4, f/5.6, f/8).   Last night I spent a LOT of time observing at f/8 and also at f/5.6, way more than any others.  Maybe that explains my preference this night for the 6.5nm instead of the 3.5nm??

 

Observing this week and last with such a wide array of camera lens speeds (f/1.2, f/1.4, f/1.8, f/2, f/2.8, f/4, f/5.6, f/8), and with different filters, REALLY makes me appreciate more than ever having a continuous manual gain control.  If you are reading this and shopping for an NV device, I encourage you to make sure the device you buy checks that box!

 

Observing with the 800mm was very cool, I spent a lot of time with that and a 6.5nm filter.  Astronomy is maybe not your typical application an 800mm camera lens, but it works!  Actually there was also a time (this past spring) hiking with my wife and son in Talladega National Forest in Alabama where I carried that lens with 2x TC along for bird photography, and at a rest stop I told my wife & son let's do a quick portrait...I ran over to what seemed like the next zip code just to be able to get an upper-body portrait of them hugging, haha!  Photo turned out great...can there ever be too much compression for portraits.  So anyway who says 800mm has to be used a certain way...use it for whatever you want...even NV!

 

I finished off the night handheld with the 85mm f/1.8 lens, seeing for the first time in my life...Barnard's Loop.  How freaking cool is that!  That -- and one more look at the California Nebula -- was a pretty awesome way to cap off the night.


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#2 The Ardent

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Posted 29 September 2021 - 10:36 PM

Re: #3 Andromeda,
G1 is a good NV target. I haven’t attempted any of the others.

Big lens:
Compare with Jeff Morgan’s lens mount. Interesting solutions.

One issue I have with the vintage Nikon 180 and 135 lenses is the lack of tripod foot on the lens. No way to mount them on a tripod and they get heavy after a while handheld.

https://www.cloudyni...to-lens-for-nv/

https://www.cloudyni...8-at-dark-site/

https://www.cloudyni...-nv-and-lenses/
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#3 Mort H

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Posted 29 September 2021 - 10:49 PM

Thanks Ray for the G1 suggestion, I have never seen it but will definitely try!

 

Also thanks for the links.



#4 Mort H

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Posted 29 September 2021 - 10:58 PM

Interesting reading on those links!

 

I was fortunate in a sense to already own lenses, so no need to go buy them just for NV, just dual-purpose what I already have.



#5 Spartinix

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Posted 11 October 2021 - 03:46 PM

Thank you for having me drooling all over the place.
I used a bunch of those Canon lenses myself, like the 50 f1.2 and the 200 f1.8.

 

The thought of having an OVNI-B coupled to that is flabbergasting!

 

The box setup with the angled mirror is genius btw. I can imagine the comfort!



#6 bobhen

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Posted 12 October 2021 - 06:06 AM

Another “wonderful report” from a NV convert.

 

And yes, for the observer, NV offers a new vision of the Milky Way. One thing (of many) that impressed me was the size of some of these nebulas when, for example, compared to the Orion Nebula, which because it’s so bright gets all the press for those using just glass. But Nebulas like the California Nebula and “many others” are also huge! And of course Barnard’s loop is exceptionally long.

 

I have seen the brighter sections of Barnard’s Loop from my Bortle 8-9 location using just a 50mm guide scope. Shocking really.

 

You should also give high power a try on the core of the Orion Nebula. The view becomes almost 3-D-like and is better and more detailed and more immersive than many images.

 

Low power to high power and camera lenses to 20” Dobsonians and everything in-between it really doesn’t matter with NV. The Universe is so infinitely varied that with NV’s light boost any telescope or camera lens used at any power will offer the observer an interesting and thrilling “new perspective” of the Cosmos. 

 

Bob


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#7 Mort H

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Posted 12 October 2021 - 11:32 AM

I have yet to apply higher power with NV to the Orion Nebula, I will definitely try that out Bob!

Also thanks Spartinix for the mirror mount comment. I'm surpised these bino mirror mounts aren't more common, but perhaps the need to build your own dew shield inhibits folks.

As you were drooling, Spartinix, I was thinking the Canon 400mm f/2.8L would also be good with NV (with and without TC's). I never bought that lens for photography due to its size and weight, I have the 400mm f/4 DO and it works to carry that lens around but I wouldn't want bigger or heavier. But on a tripod for NV the big lens would be pretty good!

#8 Spartinix

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Posted 12 October 2021 - 03:33 PM

The 400/2.8... sure why not :p

I just saw the news about one of the 1200 f5.6's being auctioned for over half a mil.. that'd be 'nice' too!

 

The mirror mount is something I will consider for binoculars (where there's local light pollution) .. indeed why not more common.



#9 GeezerGazer

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Posted 13 October 2021 - 01:18 AM

Very nice systems Mort.  I have used older Nikon AiS lenses for the past 4 years with my Mod3C and micro.  Indeed, camera lenses are not optimized for NV, but they are very good, and while scopes have come and gone, the Nikons have been a staple for my NV phonetography.  

 

Jeff Morgan's version of a "sky window" using a first surface mirror serves the same purpose as your bino-mirror.  He worked it out specifically for his big Cannon lens.  

 

I made a vixen size mount for my Mod3C, so when using medium heavy lenses like the Nikon 105 (f:1.8) or the 135 (f:2), I mount the NVD rather than the lens.  For my 300mm (f:2.8) I drilled and tapped the foot and mounted a 6" vixen size dovetail.  It works great, but the "Warbler's Neck" issue becomes a problem after 45 minutes or so.  To take photos, I can't really use a mirror system 

 

Your observing report is as terrific as your NV enthusiasm.    Glad you are here.  NV would be hard to beat for H-a observing.  Many of the images in my gallery were taken with camera lenses.  



#10 Joko

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Posted 13 October 2021 - 05:37 AM

The 400/2.8... sure why not tongue2.gif

I just saw the news about one of the 1200 f5.6's being auctioned for over half a mil.. that'd be 'nice' too!

 

As you were drooling, Spartinix, I was thinking the Canon 400mm f/2.8L would also be good with NV (with and without TC's). I never bought that lens for photography due to its size and weight, I have the 400mm f/4 DO and it works to carry that lens around but I wouldn't want bigger or heavier. But on a tripod for NV the big lens would be pretty good!

This Canon 400mm f/2.8 is very impressive.

 

An other lens to consider is the AN/TVS-5.

It's a military catadioptric lens with an unbealivable 155mm f/1.2. So it's aperture is 130mm which is very close from the Canon 400mm but with a much lower f/D

Not easy to get one, also the focal plane is only a few millimeters behind the rear of the OTA.

One year ago i did a mod and it works very well with the NV binoviewer.

It gives a magnification of 5.7x and a FOV of 7°. And the views are amazing !

Here are some pics of the full system :

 

2.jpg

 

3.jpg

 

4.jpg

 

1.jpg


Edited by Joko, 13 October 2021 - 05:53 AM.


#11 chemisted

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Posted 13 October 2021 - 07:11 AM

I achieve a 7 degree FOV at f/1.2 when using my Nikkor 200mm f/2.0 lens in an afocal arrangement as described in post #19 in the following thread:

 

https://www.cloudyni...work-a-focally/

 

The views are really quite intoxicating!


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#12 Joko

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Posted 13 October 2021 - 03:42 PM

I achieve a 7 degree FOV at f/1.2 when using my Nikkor 200mm f/2.0 lens in an afocal arrangement as described in post #19 in the following thread:

 

https://www.cloudyni...work-a-focally/

 

The views are really quite intoxicating!

That sounds amazing !

Do you have any pics of this setup ?


Edited by Joko, 13 October 2021 - 03:43 PM.


#13 Mort H

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Posted 13 October 2021 - 04:08 PM

Very cool stuff, GeezerGazer, Joko and chemisted...more food for thought!

Also I like Jeff Morgan's mirror mount, it can handle larger lenses...my mirror mount is nice but is limited to the 200mm f/2.8 size, not big enough for the 200mm f/2 for example.

#14 Kstevens

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Posted 14 October 2021 - 10:47 AM

This Canon 400mm f/2.8 is very impressive.

 

An other lens to consider is the AN/TVS-5.

It's a military catadioptric lens with an unbealivable 155mm f/1.2. So it's aperture is 130mm which is very close from the Canon 400mm but with a much lower f/D

Not easy to get one, also the focal plane is only a few millimeters behind the rear of the OTA.

One year ago i did a mod and it works very well with the NV binoviewer.

It gives a magnification of 5.7x and a FOV of 7°. And the views are amazing !

Here are some pics of the full system :

 

attachicon.gif2.jpg

 

attachicon.gif3.jpg

 

attachicon.gif4.jpg

 

attachicon.gif1.jpg

Joko, what are the details of the mod to couple the ONVI to the TVS-5?
 



#15 maxmir

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Posted 14 October 2021 - 07:21 PM

This Canon 400mm f/2.8 is very impressive.

 

An other lens to consider is the AN/TVS-5.

It's a military catadioptric lens with an unbealivable 155mm f/1.2. So it's aperture is 130mm which is very close from the Canon 400mm but with a much lower f/D

Not easy to get one, also the focal plane is only a few millimeters behind the rear of the OTA.

One year ago i did a mod and it works very well with the NV binoviewer.

It gives a magnification of 5.7x and a FOV of 7°. And the views are amazing !

Here are some pics of the full system :

 

attachicon.gif2.jpg

 

attachicon.gif3.jpg

 

attachicon.gif4.jpg

 

attachicon.gif1.jpg

 

 

Is it an afocal lens or prime focus?

 

If the focal plane is so close how do you get it focus ?

 

What did you pay for it?

 

Thanks

Max



#16 Joko

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Posted 15 October 2021 - 01:28 AM

Joko, what are the details of the mod to couple the ONVI to the TVS-5?
 

 

Is it an afocal lens or prime focus?

 

If the focal plane is so close how do you get it focus ?

 

What did you pay for it?

 

Thanks

Max

Hi guys, i have a very busy day so i will explain this weekend.

Need to take some pics of the setup to show how it works.



#17 chemisted

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Posted 15 October 2021 - 01:12 PM

That sounds amazing !

Do you have any pics of this setup ?

This request by Joko has induced me to create a gallery that provides pictures of my short focal length lens setups.  I have included not only the 200mm but also the 300mm Nikkor and 400mm ST-80.


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#18 Joko

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Posted 18 October 2021 - 10:06 AM

To answer Kstevens and Maxmir previous posts, here are the explanations to adapt the lens.
This mod is designed for OVNI-B users in prime use (for afocal it would require a relay lens).
It cost me a bit less than 200€ for the lens and parts.
I've also done an adapter to use filters, not tested yet, it will be probably this week.

What you need is :
- 58mm male to 48mm female ring AND 48 male to 48 male ring adapter. See pic 1.
- OVNI Multi adapter (1.25" & 2" barrels with thread for filters, c-mount, 42mm, T2). See pic 2.
- and of course AN/TVS-5 lens + OVNI-B. See pic 3

1/ Thread the 42male to 42male ring adapter in the 58mm male to 48mm female ring
2/ Position it to be well centered with the back glass of the AN/TVS-5 and glue it (not on the glass).
3/ Make sure it's well glued then when you want to use the lens, just thread the OVNI-B with the top part of the Multi Adapter.

1.jpg

2.jpg

3.jpg

Edited by Joko, 18 October 2021 - 03:02 PM.


#19 slavicek

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Posted 18 October 2021 - 08:37 PM

Great report and great contraption!

FYI, I and others here attacked the overhead viewing and neck pain problem with T-2 prism diagonal mounted behind the NV = between NV and your eyes (acting like eyepiece diagonal). It's more compact. My problem is that I am very shortsighted, so I cannot completely focus my eyes even just looking thru the T-2 diagonal. You may want to give this idea a thought.

Also, I have done some preliminary testing with short light path 1.25" diagonal placed between the Canon lens and the NV and it looks like I can still bring the image to focus! Now that would be the ultimate "neck pain" solution! I am working on that and on couple other things at rather slow pace (due to covid restriction of use of machine shop).

Anyway I do not want to take over your thread, however I think you may find the above interesting. I will start my thread when I am (finally) done with my Mods... probably by Spring.



#20 Mort H

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Posted 18 October 2021 - 09:12 PM

Interesting indeed, thanks slavicek for more great ideas!

#21 Mort H

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Posted 19 October 2021 - 11:15 AM

slavicek...you really got the wheels turning in my head! I'm traveling currently but am thinking of something to try when I get home...

#22 slavicek

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Posted 19 October 2021 - 05:28 PM

slavicek...you really got the wheels turning in my head! I'm traveling currently but am thinking of something to try when I get home...

I kind of figured that! That's why I wrote my reply lol.gif

The only news I have at this moment is that I just ordered FRONT mounted Ha filter for my Canon 200mm f/1.8 lens (110mm dia front lens). The back mounted filters just do not work well on this fast lens. So there is lot of issues when "improving" or "modding" camera lens for NV use. Challenge is to solve them. Sharing our ideas among ourselves will help all of us to do better.

 

I just hope that the machine shop in our club will open soon so that I can get going again with my astro contraptions and MODs.



#23 Mort H

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Posted 19 October 2021 - 08:48 PM

200mm f/1.8 with front filter sounds awesome!

#24 The Ardent

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Posted 20 October 2021 - 11:42 PM

With my Nikon AIS 135 and 180, the Astronomik 36mm H-alpha filter fits over the rear lens , and inside the pins and projections that surround the lens. A tiny bit of double sided tape (1-2mm) held it in place. It’s a 40 year old used lens, a little bit of tape won’t hurt it. It worked very well. The filter cell is thin just barely thicker than the filter itself. 

 

The drawback is inconvenience or removing the filter for normal use. 



#25 maxmir

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Posted 23 October 2021 - 10:59 AM

There are TVS-5 lenses in new condition on ebay now. He wants $1,300 for each lens. I think that's a little steep. I made him an offer of four hundred bucks. He countered with a offer of $900. I'm passing on it for now

There are smaller used PVS-4 objectives for around 200 dollars on ebay

They are about 105mm FL and about F1.2


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