SolaresLarrave
My M5s need red dots!
First... what do the words EP mean?
These words, enclosed by a diamond shape, are engraved in the rewind crank of my Nikon S2. I recall having seen someone asking about a Nikon RF camera in eBay, whether these letters were in a camera body that was being auctioned.
Also... why and what brought about the infinity lock?
Was it to copy Leica and Contax? Why didn't they do away with it? What purpose does it have, other than setting the lens for removal?
Thanks a lot!
These words, enclosed by a diamond shape, are engraved in the rewind crank of my Nikon S2. I recall having seen someone asking about a Nikon RF camera in eBay, whether these letters were in a camera body that was being auctioned.
Also... why and what brought about the infinity lock?
Was it to copy Leica and Contax? Why didn't they do away with it? What purpose does it have, other than setting the lens for removal?Thanks a lot!
SolaresLarrave
My M5s need red dots!
Thanks for your replies! I didn't have the slightest clue about the letters... but must admit that I had a feeling that the infinity lock responded to some weird notion of practicality. I don't have a problem with its existence, and it doesn't bother me that three of my lenses have it, but it makes me wonder about its usefulness.
Again, very thankful!
Again, very thankful!
Dwig
Well-known
Its probably impossible to ever know exactly why the designers of various cameras included an infinity lock in the feature set.
On the other hand, its easy to see some distinct advantages to it. The big one, and likely at least part of the reason it exists, is that mounting and unmounting a lens is often easier when the focusing mechanism doesn't move. One the Nikon/Contax mount, the helicoid is in the body and there is no way to easily hold it still while twisting a 50mm lens to mount and unmount. The infinity lock, for these lenses, is quite handy. The same is true with many of the smaller LTM and M mount lenses were there is little to hold that doesn't turn. In fact, some of the early Leitz lenses had nothing gripable that didn't turn as the lens was focused. Without an infinity lock you have to put load on the stop at the end of the focusing travel when mounting and unmounting the lens. You also have to twist the lens an extra amount, ofter 1/2-2/3rds of a revolution, to mount or unmount as a result of the focusing mechanism turning.
When Nikon developed the F-mount for their reflex line they incorporated a dedicated grip ring around the waist of the lens to provide a rigid non-rotating surface for mounting and unmounting, thus bypassing the need for an infinity lock.
ZeissFan
Mentor
Infinity locks aid in the removal of the lens. Try removing a Nikon RF 50mm lens (or Contax RF, which is where Nikon got it) without the lens locked at infinity, and you'll see what I mean.
Sometimes, the simplest explanation is the easiest.
Sometimes, the simplest explanation is the easiest.
Tom A
RFF Sponsor
On the Nikon/Contax - removing or putting a lens on without having the helicoil at infinity can spell disaster. You can jam the whole thing and literally have to saw the lens into two parts to get to the locking spring!!!! Know all about it - have had to do it once (old, external mount 85 which was thankfully in really crappy shape before I hacksawed the rear of it!!!!!). The flat spring on the mount can grab the mount and get stuck!
david.elliott
Well-known
Eek! That sounds awful.
back alley
IMAGES
i love your stories tom!
Tom A
RFF Sponsor
Using cameras - stuff happens. The hacksawed 85 was thankfully the only time I had to do that! However, last year a Nikkor 35f1.8 decided to jam on to my black paint S3 Millennium!!! This was a set I was not going to hacksaw. I managed to bend a dentists "scaler" that my dentist had given me (they make really good small screwdrivers!) and. putting the camera on B - could hook it on to the release spring and pull it back sufficiently to release the lens (with the help of a largish wrench on the lens barrel. No damage to the camera and only some additional scratches to the knurled part of the lens barrel! Turns out that the locking spring on the S3 Millennium is very soft, chromed brass and it had simply bent and jammed the lens. I replaced it with a steel spring from an old, defunct, Nikon S - but I still am leery about putting external mount lenses on that body.
Good to know that about the S3-2000! I usually keep the Millenium Nikkor on it, and use the vintage SP for external mount lenses.
Except for the very early S3 2000 bodies where Nikon didn't get the mount quite right (see this thread), I've never had a problem with external mount lenses on reissue Nikon RFs. I use my 2 x SP 2005 bodies with external mount lenses all the time.
eia41
Established
<EP> literary means Export Permit - and stamping it on the camera body saved the owner the hussle of proving that he was the legitimate purchaser/owner of a photo product the exportation of which from Japan was, for a period of time, controlled by the allied occupying forces (ie the US)
aoresteen
Well-known
Humm. I have always thought that EP stood for "Exchange Program" meaning they were for sale through the military Exchanges (Army, Air Force, & Navy) and could be leaglly imported to the USA by military persons and the trademarks could remain intact.
Canon cameras had this engraving as well.
Canon cameras had this engraving as well.
DanOnRoute66
I now live in Des Moines
...Except on eBay, where it means Extra Pricey.
SolaresLarrave
My M5s need red dots!
Mike, that was the thing I noticed, but I simply wanted an additional reason for the lock. Apparently, there's none other than aiding the process of mounting and unmounting a lens.
BTW, I really like my Nikon S2!