M8 images with Sweeney rebuilt J8 lens

ampguy

Veteran
Local time
11:37 AM
Joined
May 15, 2006
Messages
6,946
This set comprises mostly of test pics from my '80s black J8 rebuilt and focus adjusted (previously it back focused) by Brian Sweeney.

It's an impressive lens, very sharp (check out 100-200% crops of the telephone pole), has the Sonnar type Bokeh and now focuses correctly.

I purposely left in some images with flare and a few under and over exposed to show how the lens behaves with the M8.

I used a Heavystar conical vented 40.5 hood, no filters, and am wondering if some of the indoor flare shots may have benefited from a non vented hood.

A couple of the images could have used a UV/IR filter, and all the images had the Picasa "I'm Feeling Lucky" contrast adjustment.

Very amazing lens.

Flickr link here
 
Wow, had I known that the j8 had so much potential I might have not sold mine to Brian...just kidding, it needed to be Sweenyfied before it could be viable. Really though, great results!
 
This M8 is the best friend that a Jupiter-8 ever had. Great for adjusting the shims!

The J-8 that ampyguy sent had a weird problem with the aperture, it bent backwards hitting the surface behind it when stopped down, smearing oil on it. Never seen that one before! I had a spare otpics module from a Zeiss conversion, I think it was RFF member Franks' conversion. It's feeling much better now!

and Joe--- your J-8 got Sonnar-fied...

picture.php
 
Now interested in a J3

Now interested in a J3

I'm now very curious how a properly focusing J3 1.5 lens would work. Is it any larger than a J8?
 

Attachments

  • IMG_1425.jpg
    IMG_1425.jpg
    43.5 KB · Views: 0
How did you adust this lens?

How did you adust this lens?

Brian,

I have this same lens and I have noticed it does not focus on my M8. I know this is probably due to it being more in spec for the Contax standard than Leica, so I adjust my focus a bit to get close. How difficult is it to modify the lens? Do you have any pics of the procedure?

The most I have ever done to a FSU lens is take apart my Industar 61LD for a lube job (I found this lens easy to take apart and a pleasure to work on).

While we are at it, how do you adjust the Industar 61LD? I have 2 of these and would like to take one and adjust it for my M8 as well.

Thanks,

Ed
 
J-3 Lube Job:
http://ziforums.com/showthread.php?t=374

J-3 Adjustments:

http://ziforums.com/showthread.php?t=374

Kim Coxons site with J-3, J-8, and many more:
http://pentax-manuals.com/repairs.htm

It is a fairly easy job to adjust the J-8 and J-3.

The Industar 61L/D is a little easier. Take out the rear light baffle, I use some "stretch" type pliers used for Cotter Pins. Then, take out the retaining ring- you will need a Spanner. There is also one screw on the side that needs to come out, holds the module in. I made a ring, about 0.2mm, put in the focus mount under the optics module, put the optics back in and tightened up.
 
Last edited:
My 1953 KMZ Jupiter-3 on the M8, collimated using the M8.

Wide-Open at F1.5
picture.php


Distance, F4 ( I LOVE 1/8000th speed on the M8)
picture.php


What a mean Dad I am. Pink hats make such tempting Snowball Targets.
picture.php


Slightly larger than the J-8, uses 40.5mm filters.
picture.php
 
Last edited:
One more with a J-3, wide-open on the Canon P.

picture.php


I have to use THIS J-3 on the M8, it is modified to focus to 0.8m.
 
An Incredible lens!!!!!

An Incredible lens!!!!!

Boy, I am floored! After viewing through Smugmug I am speechless. For the price this lens is a hidden treasure. I noticed the better separation of shadow and highlight with a gentle transition, no doubt due to a lower contrast older design. These things really shine with a digital sensor. Much more so than the modern lenses that clip highlights that are too contrasty!!
 
Yup

Yup

And all of those images (same ones on flickr and smugmug) are reduced sizewise to 800 pixels, as well as quality/size reduced with Picasa's "Automatic" reduction setting.

So these images viewed in "Original" mode, are only about ~200kb file sizes each, while the images direct from the M8's SD card are ~3.5 - 5MB in file size.

Also, no sharpening was applied at all. A bit of sharpening, saving with Picasas "Maximum" setting, and going up to 1024 or 1200 on the long side, would all make them look even more incredible.

Boy, I am floored! After viewing through Smugmug I am speechless. For the price this lens is a hidden treasure. I noticed the better separation of shadow and highlight with a gentle transition, no doubt due to a lower contrast older design. These things really shine with a digital sensor. Much more so than the modern lenses that clip highlights that are too contrasty!!
 
Been meaning to contribute to this thread but couldn't get the time until today. I shot some pics around the house. This is a sixties chrome J8, not sure what Brian did to it--he sold it to me attached to a terrific Zorki-3M! It is superb on the M8...sharpness stopped down is excellent, and wide open it has quite a beautiful desaturated, pastel-ish quality. Really nice in color. Focus is spot on, thanks, Brian!

4405967927_73da2cf7fd_o.jpg


4405967841_33a0bf07cc_o.jpg


4406733646_03d5916ffc_o.jpg


4405967629_a0f3209299_o.jpg


4405967525_945ce4f911_o.jpg
 
That particular J-8 module was left over from a Zeiss conversion, and then put into a mount that I freed-up after getting Joe's J-8. It was a three-way head Transplant just like in the horror movies.
 
John, some of your shots seem to have less DOF than a usual 50/2, is it possible your aperture is opening wider like to 1.7 or so? Does it meter like a standard 50/2?
 
Back
Top Bottom