Possible alternative to barlows/teleconverters (1 Viewer)

[JGobeil]

Jules,
I just received the Teleplus 2X macro TC, looking great.

Mine has OM fitting. I plan to test it with an OM 50mm 1.8 to get a feeling how it performs.

What I still miss is a 2" prime focusing adapter for OM. I already have OM-m4/3 adapter (or actually going through 4/3 i.e. OM -> 4/3 -> MMF3)

The mimum length adder would be the 1-piece 2" prime focusing adapter from e.g. CNC supplies and OM-m4/3 adapter. In your case, substitute OM with Canon FC.

Thanks Tord,

I don't think I want to go that route - too expensive. I already have a TN that works quite well and a 2X ED barlow so I don't really need it. I don't care for the macro part of the TC so I might just want to open the TC to get the element and install it inside a M43 extension tube. Does anybody know the diameter and thickness of the TC element inside ?

Regards
Jules

 

[Paul Corfield]

Thanks Paul, I shall keep my eyes open

What are some quality glass/built brands other then Teleplus/Vivitar and Panagor?

Within an affordable budget there's only really Teleplus/Kenko and they probably made the Vivitar one too. Vivitar is just a brand name and loads of different glass makers made lenses for them. There may be other surprises that turn up but I've tried nearly all the budget 2X MC7 TC's ever made.

Paul.

 

[Paul Corfield]

Does anybody know the diameter and thickness of the TC element inside ?

Regards
Jules

Rear diameter is quite large at around 1 3/8" (rear element is around 1 1/4") and length of the lens housing is about 1 1/2"

Paul.

 

[JGobeil]

Rear diameter is quite large at around 1 3/8" (rear element is around 1 1/4") and length of the lens housing is about 1 1/2"

Paul.

Thanks Paul. That is quite big...

 

[Tord]

I now have all the components needed and plan to test the device coming days. It's quite heavy though (it feels heavier than the 2.0x Zuiko 4/3 EC20 and with the two extra adapter rings that are needed it builds about 5cm length to the setup so setup balance is impacted. I guess I will use a shorter extension tube, sacrificing short focus distance.

I will keep you updated and hopefully have some pictures to share.

 

[Tord]

I tried the Teleplus 2X macro teleconverter the past weekend. The drawback is that it is a quite big and heavy lump that changes the setup balance substantially, more than my 150mm Arca-Swiss rail can compensate for. Near and far focus ability was also impacted quite a lot so I need to re-think.

Results? Will have to wait until I have resolved the issues.

 

[JGobeil]

I tried the Teleplus 2X macro teleconverter the past weekend. The drawback is that it is a quite big and heavy lump that changes the setup balance substantially, more than my 150mm Arca-Swiss rail can compensate for. Near and far focus ability was also impacted quite a lot so I need to re-think.

Results? Will have to wait until I have resolved the issues.

I took the TC element out of the Minolta I purchased. I'm now waiting for a M43 extension set.

The TC was difficult to take apart because some parts were glued... A Dremel tool was needed.

 

[kurakura]

just managed to get myself a vivitar macro 100-200mm: believe it says Sakar MC - Zoom C/Macro with a 2x teleconverter. So now I am going to kill it hehe...

It is for Olympus mount, So if anyone can use the housing or the 2x converter let me know

 

[kurakura]

ooo a quick question, I know I asked before, but now I cannot find it...: how does the TN effect the fstopo/aperture???

 

[Tord]

ooo a quick question, I know I asked before, but now I cannot find it...: how does the TN effect the fstopo/aperture???

For a magnification of square root of two (~1.4) you lose one F-stop.

The amount of magnification you will achieve depends on the TN element. A 100-200 lens I stripped down had a TN with magnification 1.45x, so a little more than 1 F-stop. A 80-210 lens had 1.62x / 1.3 F-stop and a 35-80 had 2.45x / 3 F-stops.

 

[JGobeil]

For a magnification of square root of two (~1.4) you lose one F-stop.

The amount of magnification you will achieve depends on the TN element. A 100-200 lens I stripped down had a TN with magnification 1.45x, so a little more than 1 F-stop. A 80-210 lens had 1.62x / 1.3 F-stop and a 35-80 had 2.45x / 3 F-stops.

Magnification also depends on where you place the TN element. Magnification will increase with the distance from the sensor.

I have one from a Canon 100-200mm that gives me from 1.45X to almost 2X, depending where I place it in the extension tube. I set it at 1.5X and it works just fine.

 

[Tord]

Magnification also depends on where you place the TN element. Magnification will increase with the distance from the sensor.

I have one from a Canon 100-200mm that gives me from 1.45X to almost 2X, depending where I place it in the extension tube. I set it at 1.5X and it works just fine.

Jules,

You are absolutely right. The magnification figures I shared were measured with the TN element mounted in a macro tube placed between the extension tube and the camera body.

I too think ~1.5x (~1.1 F-stop loss) is about right.

 

[kurakura]

just managed to get myself a vivitar macro 100-200mm: believe it says Sakar MC - Zoom C/Macro with a 2x teleconverter. So now I am going to kill it hehe...

It is for Olympus mount, So if anyone can use the housing or the 2x converter let me know

turns out to be a 80-200 f4.5... these can be from 3 different factories ( Kiron, Komine and Kobori) whereas the 100-200 only been made by komine... have to investigate further

From the camera end lens looks like this:

Lens-iris-lens-zoom mekanism with 1lens at the back and 2 lenses put together - front element...

Now which one is the TN???

When taking the thing apart I was using blutac like Paul have described here - this took off a locking ring holding the 2lens element in the zoom so they came right out, have put them back in... got a hunch they might be the TN

 

[Tord]

Now which one is the TN???

The TN is the biconcave element that moves back and forth when you operate the zoom. It's located "somewhere in between the front lenses and the rear lenses". It's usually in a metal housing that can be useful as support when mounting it inside a tube. I wrapped the housing in electrical tape for perfect fit.

 

[kurakura]

vivitar

here is a picture of the pieces... so I suspect it should be in the middle section.

closest to cam is 1glass and infront two elements...

to me it doesnot seem like any are biconcave

 

[kurakura]

actually the from one of the focussing part consist of 3 elements:

front lens is planoconcave, next seems to be two pieces stuck together forming a negative meniscus, so front piece fits right over it

 

[kurakura]

test

well i thought I would just test the 3 element (doublet+single) to see if it magnifies anything. pictures taken through window with alot of greasy fingers from the kids and without much attention to focus...

I placed the elements as close at I could get them in the t-adapter and get about 3x mag


What might be just as interesting is that I think I can modify the iris with housing to fit in between adapter and scope/extension

 

[DanC.Licks]

You might get a lot of vignetting if you do. I have found that to be the case when I have mounted an iris too close to the camera. It belongs further forward.
My TN gives me 1.6x magnification close to the camera body. 3x sounds extreme. The image above shows camera movement. Hard to manage with that kind of magnification.

 

[kurakura]

I have found a biconvex lens sitting right infront of the iris... that renders 1,5-1,6x when placed in the adapter.

So this must be the TN... but other thing gave 3xmag... have to play more with both of them hehe

 

[kurakura]

Here is the mountsection with Iris and TN inside, fits perfectly as a cameraadapter, now I just need an oly-canon adapter... and with a bit of luck it will work hehe. If it works I have apeture control and adapter and TN in one module...