Bessa R and Jupiter 8, inner reflections?

[sbitter]

Hello everyone,
I would like to ask your advice on a problem that affects my pictures taken with a Bessa R and a Jupiter 8.

First of all here are some samples (I've made a private album on flickr):
https://www.flickr.com/gp/di_luce_riflessa/09Lg8i

as you can see there is a white-ish spot at the center of the frame.
Since it doesn't happen all the time I always thought it was some sort of flare that affects the Jupiter 8.
However I recently noticed that this "flare" does not occur when I use the Jupiter 8 on its original Zorki 4, nor when I use the Bessa R with a CS 35mm F/2.5.

So I inspected the inside of the camera and noticed a part where the black matte finish was gone, I suspect for the use of a lens with a big rear element like the J12, and maybe the "flare" was just a reflection on this lucid surface that goes right into the center of the image.
Is it possible, according to your experience?

To try to solve the problem I used some black permanent marker to paint the lucid part, but it is not nearly as matte as the rest.
I tried to paint it and then scratch it a bit with (very thin) sandpaper, but I'm not very satisfied with the result.
Can you give me some advices?
Here it is a picture:
https://goo.gl/photos/WzisDMnsx4Npvatf7

Thank you
Marco

 

[Mablo]

I think you've found a plausible cause for the flare seen in your photos. Do you see the flare only when using a J8 or both J8 and J12?

If a marker pen black is not thick enough you might try with black matte nail polish.

 

[newspaperguy]

Are you shooting with a lens shade (hood)?

I regularly use a J8 on my R and found I need the shade.

 

[sbitter]

Thanks Mablo and newspaperguy for your reply!
I see the flare only when using the J8. I have a Voigtlander 35mm, but I never had a flare with that, maybe because it is less prone to flare or maybe because it protrudes more than the J8 into the body, I'm not sure.

I don't have a lens shade for the J8, but when I used it with the zorki I didn't have any flare, that's why I thought the problem is in the camera.
I wanted to buy a hood, but I like to have the camera in a ever ready case I adapted from a zorki one

 

[nukecoke]

Thanks Mablo and newspaperguy for your reply!
I see the flare only when using the J8. I have a Voigtlander 35mm, but I never had a flare with that, maybe because it is less prone to flare or maybe because it protrudes more than the J8 into the body, I'm not sure.

I don't have a lens shade for the J8, but when I used it with the zorki I didn't have any flare, that's why I thought the problem is in the camera.
I wanted to buy a hood, but I like to have the camera in a ever ready case I adapted from a zorki one

None of my J8s have flare like this, but both my collapsible I-22 and I-50 have it, exactly the same. I think it's caused by paint loss on the inside surface of the lens barrel. You might want to check if it happened on yours. If it happened at reachable places, paint some non-shining paint to see if it improves.

 

[sbitter]

Thanks nukecoke
I actually have found some scratches in the painting of the J8, but they are in some unreachable positions, so I just hope it is the paint loss inside the camera.

I'm shooting the last frames of the film in these days, so I will know soon

 

[sbitter]

I've finally developed the film and the problem is still there.
I think that it is due to the black paint that I used which is not matte enough: looking trough the open shutter and the lens I can still see the reflection on the smooth surface.

Next move is to try to stick on the spot some black fabric or velvet.

Meanwhile I've managed to recover a few picture affected by the flare with GIMP though

 

[Ko.Fe.]

Toy models, or how do they call it, session at hobby, craft stores has black paint.
Two or three different types. One I'm using is non-reflecting.
But, this problem you have appears to be not so uncommon. I have seen it reported on different forums. But I haven't seen exact solution, yet.

 

[sbitter]

At last, a new update: finally I've solved the issue by putting on the scratched part some paper/cotton band-aid and then painting it black with a permanent marker. The irregularities of the band-aid act more as a light trap than just flat black paint.
I've shot a roll and on 36+ pictures not even one had the annoying flare!

Here is the result on the camera, hope it can help someone else too.