traveler_101
American abroad
Hi Everyone,
Just today I received a Jupiter 8 I bought over the internet. Made in 1963: lens looks clean, except for one very small blemish on the front element. The only real issue is that the focus helicoid is stiff. There is also some play in the focusing ring when you began to turn it causing a slight rattle or clicking noise when the helicoid begins to turn. Also you can make the lens rattle by taking it between your fingers and rocking them back and forth.
Good news is that it screws onto my Bessa R and seems to focus without problems. Looks excellent on the camera: proportions are right.
I don't think the looseness in the lens matters in regard to performance, and I would assume very little can be done about that on a lens that is made of aluminium and is over 50 years old. I only paid $50 for it.
Bottom line: the lens seems usable as is, but I am wondering what, if anything, I might do to improve performance of the focusing ring?
Just today I received a Jupiter 8 I bought over the internet. Made in 1963: lens looks clean, except for one very small blemish on the front element. The only real issue is that the focus helicoid is stiff. There is also some play in the focusing ring when you began to turn it causing a slight rattle or clicking noise when the helicoid begins to turn. Also you can make the lens rattle by taking it between your fingers and rocking them back and forth.
Good news is that it screws onto my Bessa R and seems to focus without problems. Looks excellent on the camera: proportions are right.
I don't think the looseness in the lens matters in regard to performance, and I would assume very little can be done about that on a lens that is made of aluminium and is over 50 years old. I only paid $50 for it.
Bottom line: the lens seems usable as is, but I am wondering what, if anything, I might do to improve performance of the focusing ring?
Ko.Fe.
Lenses 35/21 Gears 46/20
J-8 on Bessa R is nothing new to me. I have this combo for couple of years. Didn't even need to shim any of two I used (B&W).
Your copy needs CLA as any old RF lens. I just gave my Avenon 28 2.5 LTM for CLA, makes difference. Good document for DIY J-8 CLA procedure was available online.
Your copy needs CLA as any old RF lens. I just gave my Avenon 28 2.5 LTM for CLA, makes difference. Good document for DIY J-8 CLA procedure was available online.
wolves3012
Veteran
Download the PDF you can find here; http://www.pentax-manuals.com/repairs.htm It'll show you how to re-lube your lens if you want to attempt it.
ray*j*gun
Veteran
FSU (J8) lenses can be a roll of the dice. They can be marvelous lenses and in fact my fav 35mm is the J12 i picked up years ago. However they were not consistently well made. Your lens sounds like it needs service and if you film test it and it does well that's what I would recommend.
grouchos_tash
Well-known
I relubed my J8 myself no problem. Mine has a bubble in the rear element but it doesn't cause any problems as far as I can tell!
traveler_101
American abroad
Thanks, wolves, for the link and grouches for the encouragement. Raymond I just bought a J-12 and it is in excellent condition, but it was made in the 1980s while the Jupiter 8 is at least twenty years older. I used the lens yesterday on my Olympus E-P5: I like the images; it seems to be a quite sharp (centre sharp anyway), medium contrast lens. Will shoot a roll of film to confirm.
I am a willing mechanic, but I am not mechanically competent so it probably would be best to have a repairman re-do the lens. I have already failed to properly reassemble my Canon 100/3.5!
Edit: OK, I just sat down and managed this time to get the Canon lens back together. It gives me the courage to perhaps try CLAing the Jupiter 8. No need to touch the lens unit, so perhaps I can manage the rest of it.
I should use some sort of solvent - acetone? - for cleaning. What about the lubricant? What would you recommend?
Thanks for helping! Much appreciated.
I am a willing mechanic, but I am not mechanically competent so it probably would be best to have a repairman re-do the lens. I have already failed to properly reassemble my Canon 100/3.5!
Edit: OK, I just sat down and managed this time to get the Canon lens back together. It gives me the courage to perhaps try CLAing the Jupiter 8. No need to touch the lens unit, so perhaps I can manage the rest of it.
I should use some sort of solvent - acetone? - for cleaning. What about the lubricant? What would you recommend?
Thanks for helping! Much appreciated.
wolves3012
Veteran
Most versions of the J-8 are easy to disassemble, especially if you don't need to strip the optical blocks and the instructions in that PDF are very good. Just make sure you have the right tools (they can be bought pretty cheaply). Work in a tray of some sort, so if you drop a tiny screw it won't get lost. The best solvent for the old grease is something such as lighter-petrol (naphtha) and for re-greasing use a white lithium cycle grease, sparingly applied. Obviously, be aware that most solvents are volatile, flammable and not good for your health, so make sure you work in a well-ventilated area and avoid breathing the fumes!
traveler_101
American abroad
Thanks much for your help!
I've got it apart - except for actually removing the helicoid. The grub screws are so small I am left to wonder whether I can get them back on the lens; there were no problems. I had the tools and I have mineral spirits*, but I don't have lithium cycle grease. I will purchase at a cycle shop this week.
* Mineral spirits (USA) seems to be called "naphtha" or "white spirit" in Britain; translated directly into Norwegian as "hvit sprit." I have it around the house then.
thawkins
Well-known
If you need professional help try Yuri at Fedka. He CLAed a Zorki and it's Industar lens for me a few years ago turning it into a good camera. I just purchased a J8 lens from him last week. It should arrive anytime.
traveler_101
American abroad
Thanks for your post, thawkins. Apparently Yuri is a good guy; he gets lots of kudos. I was wondering about who I might send it to and hadn't thought of Yuri, so good to know. Hopefully I won't need his help this time.
traveler_101
American abroad
Progress report
Progress report
Got the lens back together tonight for the second time after some mis-steps on the first go. Now the helicoid is moving back and forth properly; it stops at its fully extend position at the infinity mark on the lens, but something is wrong because when it screws onto the camera the lens faces the wrong way and the focus ring doesn't turn.
Obviously I will have to take it apart again. Tomorrow night for another go at it.
Progress report
Got the lens back together tonight for the second time after some mis-steps on the first go. Now the helicoid is moving back and forth properly; it stops at its fully extend position at the infinity mark on the lens, but something is wrong because when it screws onto the camera the lens faces the wrong way and the focus ring doesn't turn.
Obviously I will have to take it apart again. Tomorrow night for another go at it.
traveler_101
American abroad
All that was wrong was that the keeper ring was reassembled upside down, and that meant that the screws were not flush. Works fine now, must check to see if it focuses at infinity.
Thanks again.
Does anyone have a recommendation for a hood for this lens?
Thanks again.
Does anyone have a recommendation for a hood for this lens?
Scrambler
Well-known
I use a generic vented 40.5mm thread lens hood. Chose an angled version if you have a camera with combined VF/RF or a straight version if you have a screwmount Leica or copy. The venting is to limit the intrusion of the hood into your framing.
LukeBanks
Established
I've just CLA'd a new ebay Jupiter-8 using the Kim Coxon instructions. It's surprisingly easy and I'm so glad I didn't pay somebody to do it for me now. My first try yesterday seemed to have worked ok until it seized up this morning! Luckily I got the helicoid apart again and have given it a much deeper clean and lube this time. Buttery smooth now!
For UK based people: I used methylated spirits for the cleaning which you can get from Homebase etc. For the lubricant I used white lithium cycle grease as mentioned above. Evans Cycles do a tub of their own brand FWE Lithium Grease for about £5, it has a very nice weight to it so the focus is smooth but won't slip.
Just waiting for the negs back now to make sure everything is working as it should. The lens is in great condition and the glass looks spotless so fingers crossed!
For UK based people: I used methylated spirits for the cleaning which you can get from Homebase etc. For the lubricant I used white lithium cycle grease as mentioned above. Evans Cycles do a tub of their own brand FWE Lithium Grease for about £5, it has a very nice weight to it so the focus is smooth but won't slip.
Just waiting for the negs back now to make sure everything is working as it should. The lens is in great condition and the glass looks spotless so fingers crossed!
tbhv55
Well-known
I did the same on a J-8, a few years ago, and it's very satisfying to bring a lens back to good condition. I, too, used Lithium grease for lubricating the focus, but used (IIRC) isopropyl alcohol for cleaning. As you say, the Lithium grease gives a very light and 'buttery' focus action.
Hope you're enjoying the J-8. It's great lens.
nukecoke
⚛Yashica
I just lubricated a newly bought J-8 today, with "HELIMAX XP"™ helicoid grease.
I've used it to lubricate like 10 lenses. It's one of the cheaper products I saw on the bay, but turned out good enough.
I've used it to lubricate like 10 lenses. It's one of the cheaper products I saw on the bay, but turned out good enough.
LukeBanks
Established
Hope you're enjoying the J-8. It's great lens.
So satisfying, I'd be lying if I said I wasn't like a chesire cat all afternoon! Took my first test shots today, can't wait to see those negs. Hadn't tested it before hand so I hope the effort was worth it.
I couldn't find any helicoid grease locally so went with alternatives. Yesterday I used a Silicon based grease.. bad idea. It was way too heavy for the helicoid to turn properly and I missed a couple of spots which I think made it seize up. Won't be making that mistake again!
tbhv55
Well-known
Presuming that you haven't been unlucky enough to land a 'duffer', then you should be very pleased. Image quality from a decent J-8 is pretty good. My experience that it's very nice from f/4 onwards, still acceptable at f/2.8, and a little 'dreamy' at f/2.0!
Since it's a click-less aperture ring, obviously it is very easy to nudge the aperture away from your selected setting. It will happen...
I'll be interested to hear how it turns out, when you've got some results.
LukeBanks
Established
Presuming that you haven't been unlucky enough to land a 'duffer', then you should be very pleased. Image quality from a decent J-8 is pretty good. My experience that it's very nice from f/4 onwards, still acceptable at f/2.8, and a little 'dreamy' at f/2.0!
I had about 15 shots left on a roll, just hammered off a range of apertures and focal distances in some nice daylight. I'll be interested to see how it looks at f2. The floating aperture ring is going to take some getting used to but I like the feel of it. Already guilty of knocking it out on a couple of shots! It should be ok as my R3A has the shutter speed display in the view so it was more noticeable.
Took it to my normal developer but they're busy hanging a show so won't see any results until Tuesday. Fingers crossed!