APS variable Auto Teleplus 2X-3X

[skida]

A while ago a friend gave me some old stuff he was finished with, including Praktica Nova with Tessar lens, Halina 35X and a small camera bag. I was having a rummage yesterday and came across a "lens pouch" with this M42 tele-converter in it. It looks clean and fungus-free and I am tempted to give it a go. It unscrews in the middle and the section that the lens would screw into has glass elements, whereas the other section is a hollow tube. It has the aperture pusher for auto lenses.

How much does a converter affect the image quality? I am not worried about pixel-peeping sharpness and I quite like the idea of extending my Optomax 400 to 1200 to experiment. Is it worthwhile or just worth binning?

[calvin83]

Never try this tele-converter but you can use it as a lens hood by remove the glasses.

[Lloydy]

Is it one of these ? ( Crappy pics, hand held at my desk with a Helios 44-2 on the NEX, no flash, too much wine, ISO 1600, all pic's colour corrected )


Dear me, this is bad....but you get the idea, this is the part with no glass.


This part has glass


This taken with the no glass part


and this with the glass lens part


I've used it on my K10 in the past and it's OK. There's a scale thing on the glassed part but all that tells you is the increased f stop when each part is used. It looks fancier than it is, but it is a well made bit of kit.
I only paid a couple of pounds for it, I don't use it much, but it works.

Screw them both together and you get this

On a tripod, lower ISO and decent light, that wouldn't be bad.

[skida]

That's really helpful Lloydy. It is definitely worth trying out, I reckon. Incidentally, I have seen various versions doing searches on the internet, but yours is the same version and the serial number on mine starts "419.....".


I just looked again at mine and it was screwed together the opposite way to yours, ie. the glassed section was at the lens end and the hollow section at the camera end. I wonder what difference it would make swapping them around - something else to experiment with. Happy days!

[Lloydy]

The two parts can go on each way, if the non glass part is at the back the actual glass elements are pushed forward on a spring when they screw together by the loose shroud in the non glass part. It's a strange little thing, I'll investigate a bit more today if I can

[skida]

I found that with a Helios 44M, only they have to be put together with the glass section attached to the lens. The hollow tube will not allow the lens to be screwed on, due to the moveable inner section pushing against the lens surround. I was surprised to find that the minimum focus distance is unchanged by the adapter, so 3X gives good magnification for close ups at 0.5 metres with the Helios.

I am hoping for a clear sky this weekend as it is a full, supermoon.

http://www.dailymail.co.uk/sciencetech/article-2137774/Supermoon-Biggest-moon-weekend-tides-rise-planet.html?ito=feeds-newsxml

[adonuff]

I have just checked my one out, & I think they are designed to work as follows.

1. With the extension tube removed & the bit with the glass fitted to the back of a lens you get 2X Teleconverter.

2. With the extension tube added to the rear of the bit with the glass fitted to the back of a lens you get 3X Teleconverter.

3. Swap the extension tube to the front of the bit with the glass & fit to the rear of a lens you get a macro shot at roughly 1.5X.

The results that I have been getting are pretty good, it is better than all the other Teleconverters I have tried!