Geco brand - Stumped Need help badly

guardian · Joined: 18 Mar 2009 Posts: 1746

Customarily, in matters of this nature, Google is my friend. This time, though, I found no love whatsoever on Google. So I've come to the experts. Here is the story:

Bought camera with lens in order to obtain a Konica Hexanon 50mm f1.4, my first. The lens is beautiful. Even the camera is like new. I'm delighted with the purchase.

However:

The kit came with an item that's a real mystery for me. It's a "Geco Auto Tele Converter 2X". It is made in Japan. The converter is also just like new, in pristine condition. The glass is gorgeous and unmarked. Still, this converter could nevertheless be a piece of junk optically. I am completely unfamiliar with the brand, Geco. There is no other writing on the item, save for the settings, "M" and "EE".

I don't know what I have here with this Geco tele converter. Does anyone know this brand??? Is is good, is it junk, or is it somewhere in between?

luisalegria · Expire: 2018-01-18

Probably one of a thousand temporary brand names for generic items like teleconverters. Distributors and retailers dealing in cheap photo accessories used all sorts of names.
The best way to see if its any good is to try it.
Nearly all TC's are disappointments, if one wants to judge them by pixel-peeping.
Almost any longer lens, even the cheapest, would be better. A generic 100-135mm will always give better results than a 50mm with a TC.

At the time they were an option if you didn't want to spend the cash for a longer lens, and they do have some value for close-up work, though there were better ways of doing that.

These days there are much better (and much more expensive) TC's that are used on a regular basis with high quality tele lenses. Back in those days these things didn't exist.

elliott · Joined: 16 May 2011 Posts: 170

Best use of a cheap teleconverter is to remove the glass and make it into an extension tube.

visualopsins · Expire: 2025-04-11

danfromm · Joined: 04 Sep 2011 Posts: 595

Guardian, you have the TC. Why do you ask us how good your example of it when you can ask it how good it is?

sonyrokkor · Posted: Wed Nov 14, 2012 1:34 pm Post subject:

Sometimes can help know how much elements do the converters have.

If have 4 elements, so them are near average, 7 elements should be better. The last could rivalize with some average IQ zooms.

Perhaps with not FF size, a good converter can let you have a good image, and almost nobody will know that you did use one of them.

guardian · Joined: 18 Mar 2009 Posts: 1746

luisalegria · Expire: 2018-01-18

It really doesnt take any sort of formal test in our digital world. Formal tests are necessary if one is making fine distinctions between lenses, but this isnt such a case. Such things are basically either too awful to use orthey are acceptable.
A few pictures should tell if the results are acceptable.
The moment you zoom in with Photoshop should give the answer.

guardian · Joined: 18 Mar 2009 Posts: 1746

luisalegria · Expire: 2018-01-18

There were better quality TC's available at the time.
Komura and Kiron made some 7-element types. The Kiron ones are usually seen in the Vivitar brand, but apparently they were also sold in Kiron, Panagor(another Kiron house brand) and Tokina RMC (yes, them) brands. I have one of these, and it does seem better than most, but overall its better to use a 100-135mm lens. There are great MF lenses in most longer focal lengths available very cheap these days, so old TC's as a compromise solution aren't very attractive.
Best thing to do is try it. Digital will give you your answer in a few minutes.

hifisapi · Joined: 25 Sep 2012 Posts: 941 Location: USA

To me, it always make sense to change to a longer prime than use a TC on a shorter one. The only time using a TC
makes any sense is to use it only on your longest prime because then you have nothing to lose.