[Douglas_of_Sweden]

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Note that acetone is sometimes sold with oil in it (for cleaning fingernails?). Don't use that on your lenses. You need the pure stuff.

[aurele]

i checked very carfully, it was pure acetone in my case, made to clean deeply "oily" object like mechanics

[Damian]

Hello, dear impossible member

I have some Fungus problem on my very first lens (sentimental attachment ... ahhhh !) a A50/1.7.
Right now, fungus are doing a circle on the extreme border of the back element, so, there is no consequences for the moment.

My question is what do some of you used to clean fungus, without destroying the coating (Damian ?) ?

Thanks to all of you !

Another and last question : where do you get some K mount you put on "impossible lenses" ?

Sorry so late to the discussion. I've been chasing my tail for the last several weeks. Between cub scouts with my son, my baby girl, my wife out of town for a week, work, relatives, and preparing for my annual Halloween party, I haven't had time to sleep much, let alone check my subscribed threads. I know Aliasant already answered the question, but I figured since you seemed to be asking me, I might as well be polite enough to answer. Personally I use Ronsonol, which in reality is nothing more then Naphtha. It worked well enough, but next time I might give acetone a try since most seem to agree that it works well. Normally, I just soak a flat cotton swab in Naphtha and place it on the side of the lens element needing cleaning and then put a piece of cellophane over it to lock in the vapors. Leave it like so for a while then check to see if it's doing the job. Anyway, I'm glad your cleaning met with success. Don't forget to bathe the lens in UV light for a few hours a few days in a row to kill any fungus you can't see. Oh, and welcome to the thread, I'm a relative new comer myself.

Update on other projects: I finally, after three separate orders to china, got the 62mm reverse macro adapter I need to complete the Topcor 5.8cm f1.4 conversion. I was sent 58mm adapters with step up rings twice instead of the "pictured" 62mm one piece adapter. I'm glad the sellers were reasonable enough to refund my purchase and let me keep the extra adapters. Apparently 62mm reverse macro adapters in k mount are becoming scarce. In hind sights I probably should have done what Ripit suggested and just used parts I had on hand to make a shim, but hey, I have what I need now. I'll try to get to this in the next few weeks, but things are getting more and more hectic by the week as we approach the holidays. I'll get to it eventually. I'm probably going to have to shelve the Canon FL bellows conversion till after Christmas though. If only I could buy time in a can.....

[aliasant]

I have been thinking about making something like this for years but never really got any bright ideas.
Couple of days ago i suddenly realised how I could do it so here it is.

I used a rubber ring ( for plumming perhaps? ) and a metalring + a pentax mount.
The metal ring is from some lens in my own little lens scrap-yard
It has the same outer diameter as the mount and would give a little extra space for the rubber ring to flex in.
I attached the ring with screws from the mount but those screws ended up inside the ring but with some tension. Some good glue and its not going anywere.

To preserve the flex I thought I could sew the rubber onto the ring so I drilled a lof of small 1.5mm holes in the ring and then sewed on the rubber thing.

Now my Bronica lens fits perfectly into that ring and flexes quite a bit.
I can reach infinity by pulling the lens towards me. Releaseing it will give a focusing distance of about 2 meter and pulling it further away gets me closer.
I can also adjust the lens in the rubber since its not glewed and get a close focusing of about 30cm.
Not ideal but for now im pleased. Infinity is the important part and I got that

I really would like to have something like a Bronica mount instead so that I could use other Bronica lenses or maybe some other Medium format lens?
Ideas would be much appreciated. My knowledge of medium formats is almost zero.

Here are some of the testshots I took yesterday and some of the lens and adapter.
All Tilt shots taken at f4. The shots of the lens are taken with my PK converted Topcor 35/2.8.
No PP except some levels in LR and a little bit sharpness. Bigger images if you click on one of them.

[ovim]

Very nice results! Especially the park bench shot is great.

[aurele]

DYI tilt adapter niiice !

Shots looks great ! You will have some nice time with it, i hope so !

@ Douglas, i just saw an ebay auction for a Konica Hexanon 40mm f1.8 i would love to have one, but short registration + pancake lense = Ultimate impossible lense

Here is the link if you want KONICA TC-X DX + 2 OBJECTIFS voir detail | eBay

[aliasant]

Very nice results! Especially the park bench shot is great.

DYI tilt adapter niiice !

Shots looks great ! You will have some nice time with it, i hope so !

@ Douglas, i just saw an ebay auction for a Konica Hexanon 40mm f1.8 i would love to have one, but short registration + pancake lense = Ultimate impossible lense

Here is the link if you want KONICA TC-X DX + 2 OBJECTIFS voir detail | eBay

Thanx guys. It sure is a fun lens to use. Very addictive. Even more so then Acetone....... or was it ... never mind.

[aurele]

Even more so then Acetone....... or was it ... never mind.

i don't feel that this is for me, not at all


let's be serious again.

Monday, i'll get my Vivtar S1 70-200 f3.5 in olympus mount, that is will convert on K mount.

I was wondering if any of you know how the "A" seting in the KA mount work ?

I can see that in "A" setting a pin is contacting the mount, and not when aperture is set on any other value.

(yes, i would love to produce some KA mount from a simple K)

When i cleaned my A50/1.7 i saw no specific chip or contact of any kind that may help the body.

Sooooo : if there is that "A" pin, the other contact that tells the body the biggest and smallest aperture, will the lense work like a KA or there is something i'm missing ? Is the lever always working the same way for all K and A lense ?

edit: the lever doesn't not work the same way on K and A mount.
K mount use exponential relation between the movement of the lever and the closing of aperture. A mount is proportional.

damn !

[Douglas_of_Sweden]

i don't feel that this is for me, not at all


let's be serious again.

Monday, i'll get my Vivtar S1 70-200 f3.5 in olympus mount, that is will convert on K mount.

I was wondering if any of you know how the "A" seting in the KA mount work ?

I can see that in "A" setting a pin is contacting the mount, and not when aperture is set on any other value.

(yes, i would love to produce some KA mount from a simple K)

When i cleaned my A50/1.7 i saw no specific chip or contact of any kind that may help the body.

Sooooo : if there is that "A" pin, the other contact that tells the body the biggest and smallest aperture, will the lense work like a KA or there is something i'm missing ? Is the lever always working the same way for all K and A lense ?

edit: the lever doesn't not work the same way on K and A mount.
K mount use exponential relation between the movement of the lever and the closing of aperture. A mount is proportional.

damn !

Best explanation I know of for the A contacts are Features and Operation of the Ka Mount
They transfer no info, there is no chip in the A lenses, the 6 contacts is just a sort of binary code for the min and max apertures. So you can code your own non-A K lenses, but as you noticed, they also changed the aperture leveler from exponential to linear (what you call proportional). Note that there are a few exceptions. Some late copies of M lenses got linear aperture transfer as well. Most commonly is the last version of the M28/2.8. I think also late versions of the M80-200/4.5, perhaps a few more. These could be converted to true A lenses.

[aurele]

thanks for the link, i've read it just before writing my last post

This morning i tried to convert a Vivitar S1 70-200 f3.5 (1st version) OM to K mount. it's a fail so far

First, the lense had been "repaired" before. but it was more like a aesthetical repair, not a very efficient repair. I had to disassemble a big part of the aperture mecanisme, to repair it.

Then, i tried to hack the mount, using the K mount of a 70-200 f4.5 zoom i have, which is very bad btw. Sadly, the mount from the zoom as some metal parts under the mount (is that clear ?). So it didn't fit.

This afternoon i will look for a K mount, but i don't have a lot of hope...

DAMN IT ! i really want to use this huge lady, she can do so much !!! Aaaargh !

[hoanpham]

try to get som cheap cheap third party TC or tub and use the K mount from these to the lens. You may have to drill new holes to fit the lens, but it should be doable.
No auto aparture then, but it should work. You may also jam the aperture pin in one fixed position to force the lens to work like a takumar.

Dremel too, is a useful tool ;-)

[aurele]

You may also jam the aperture pin in one fixed position to force the lens to work like a takumar.

i never use a tak so far but i guess that you mean to force the lense to always be "open" on the aperture set ?

Dremel too, is a useful tool ;-)

Yeah ! i discovered lately that i really need one i'm a little short on money this month (5 films processed, 100 films prints, 2 film enlargement, cost arms and legs !) so i will see if the big bank called "Parents" can help me, and give me fifty bucks for free

[Damian]

Finally made a Tilt adapter for my Bronica S2 lens

I really need to check the forum more often. That's awesome aliasant! Great job. It's amazing how many great diy ideas pop up in here.

[Steinback]

One of these days I need to find some time to hack together simple k mount tilt and shift adapters for my 645 A 75mm f/2.8. It's small, light, and has about 25mm of space behind it to fit an adapter into, plus I shouldn't need to buy much in the way of parts.

[ripit]

i never use a tak so far but i guess that you mean to force the lense to always be "open" on the aperture set ?



Yeah ! i discovered lately that i really need one i'm a little short on money this month (5 films processed, 100 films prints, 2 film enlargement, cost arms and legs !) so i will see if the big bank called "Parents" can help me, and give me fifty bucks for free

It means that when you change the aperture ring to a smaller aperture it immediately closes down the blades. You can change the aperture with the ring but the camera has no connection or control over the lens or its aperture including no stopping down from the camera.

Fyi if I understand your problem with the donor mount correctly, there were parts on the mount that kept the mount from seating down. Your option is to remove parts and or grind down, file or whatever to remove what is not clearing. If you are expecting linkage to work etc, you are going to have to learn to make small parts and or do more complex modifications.