Author Topic: I just made/fixed ...  (Read 108105 times)

Francois

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Re: I just made/fixed ...
« Reply #200 on: November 17, 2017, 08:31:31 PM »
Last night I worked on James' Kodak 35 I got through Share the love.
The camera works fine but the 1938 grease that was in the focusing mechanism made things difficult to say the least.
Took it apart, used a dab of Lithium grease, re-calibrated the focus and now it's ready for another 80 years of picture taking :)
Francois

Film is the vinyl record of photography.

cs1

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Re: I just made/fixed ...
« Reply #201 on: November 17, 2017, 08:37:21 PM »
Nicely done, François. I'm wondering: how did you recalibrate the focus? I've tried it once on a Voigtländer and failed miserably (though before shooting a roll of film I was pretty confident that it went well).

Francois

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Re: I just made/fixed ...
« Reply #202 on: November 17, 2017, 09:55:46 PM »
The trick is super simple. I do what is called reverse-collimation.
I have a piece of film on which I made some pretty big scratches on the emulsion side.
I tape it inside the camera and leave the camera back open. I put my desk lamp so it light through the scratched X.
You open up the shutter and leave it open using a cable release if the lens doesn't have a T setting.
Now, using a big telephoto on another camera, you just focus through the lens of the camera that needs fixing.
Rotate the focus until you get perfect focus on the film. Lock the infinity at that point.

That's all there is to it.

You do need a lens of at least 210mm for it to work. More the better.

Eventually, I might make myself some sort of jig to hold everything, but just setting things on the desk works just fine.
Francois

Film is the vinyl record of photography.

cs1

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Re: I just made/fixed ...
« Reply #203 on: November 18, 2017, 09:07:43 PM »
To be absolutely sure I understood you correctly (sorry for ascii-arting this):

Code: [Select]
#===           =#  ?
|               |  |
|               |  +---- Light source
Camera          Camera (to be adjusted)
w/              w/
>210mm          scratched Film

When you focus the tele lens, how do you know if the film is in focus if the camera that needs adjustement hasn't focused to infinity? It's very likely that I'm just too stupid to understand this method properly so thanks in advance for your patience. :)

Francois

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Re: I just made/fixed ...
« Reply #204 on: November 18, 2017, 10:59:14 PM »
OK, lets try it with a drawing.
I redid it and found it works better with a multi-LED flashlight as it gives better light with less flare.
So, you have a setup like below.
I used a 500mm lens on my second re-focusing and found it much easier to do than with a 210mm.
Now when you look through the lens of the camera that needs focusing, the scratches will be soft and out of focus. As you move the focus on that camera, you will be able to get the scratches in sharp focus. You can see the emulsion slightly peeling on the side of each scratch. It's that much magnification.
All you have to do is lock the focus on infinity when the scratches are in focus.
Francois

Film is the vinyl record of photography.

cs1

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Re: I just made/fixed ...
« Reply #205 on: November 19, 2017, 01:51:21 PM »
Thanks so much for the instructive sketch. Now I understand how it works. Great writeup, François, it's highly appreciated.

Bryan

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Re: I just made/fixed ...
« Reply #206 on: December 27, 2017, 11:23:26 PM »
I'm not great when it comes to lens repairs but I just completed one of the more difficult ones.  I recently got a great deal on a Leica IIIa with a Summar lens that was in desperate need of cleaning.  To get to the inner lens element I accidentally set the iris blades free.  Looking for clues how to put them back together it was clear that even the repair technicians hate putting these back together.  I spent several hours today fiddling with it before I finally got it back together.  I don't ever want to do that again.  The lens had a lot of gunk on the inner elements that I was able to clean.  There's still a little haze on the rear element but a few tests with it mounted on my digital camera shows that it will do just fine. 


Francois

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Re: I just made/fixed ...
« Reply #207 on: December 28, 2017, 03:35:31 PM »
Fixing aperture blades is definitely a pain. I've done it more than once and it's never fun. But when you manage to get it right, boy is it a thrill!

Sometimes haze is caused by a thin layer of grease. One of the best lens cleaners is liquid dish detergent. It's safe on the lenses and coatings. Rub it with your fingers and dry with an old piece of t-shirt very softly.
Francois

Film is the vinyl record of photography.

Bryan

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Re: I just made/fixed ...
« Reply #208 on: December 28, 2017, 05:24:29 PM »
The dome shape of the iris blades on the Summar make it even more difficult.  The trick was to hold them in place while inserting the last few.  I used small pieces of cardboard taped to the outside of the lens barrel to push down and hold them in place.  I was constantly moving the pieces of cardboard to allow another to go into place. 

The haze on the inner element was a layer of grease so that was easy to clean.  The rear element haze is between the glued elements so that can't be cleaned.  It's not bad enough to have much effect on the image. 

Francois

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Re: I just made/fixed ...
« Reply #209 on: December 28, 2017, 08:52:30 PM »
The only way to get there would be to de-cement the glass and re-cement it back... I don't know how to do the first part except with a hammer and chisel  ;D
Francois

Film is the vinyl record of photography.

Bryan

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Re: I just made/fixed ...
« Reply #210 on: December 28, 2017, 10:19:49 PM »
There are a few repair shops out there that do it but I'm afraid to ask how much it will cost.

Francois

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Re: I just made/fixed ...
« Reply #211 on: December 28, 2017, 10:27:44 PM »
I know you can get the required materials at Edmund Scientific's Optics division.
The glue used cures using a high powered UV light.
Francois

Film is the vinyl record of photography.

Bryan

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Re: I just made/fixed ...
« Reply #212 on: December 28, 2017, 11:53:50 PM »
They use heat to separate the elements.  If it’s not done correctly you can easily crack the glass.  It has to be cooled down slowly.  I’m sure there are a lot more tricks to it that we don’t know about.

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Re: I just made/fixed ...
« Reply #213 on: December 31, 2017, 05:30:30 AM »
I took the plunge and took the Leica IIIa apart today, the one that came with the Summar lens mentioned above.  I couldn’t believe how much crap came out of that little camera, dirt, dead bugs, rocks, leaves, cigarette butts...  I cleaned the slow speed escapement, cleaned the pressure plate, inspected the shutter curtains, re-glued the leatherette and got it all back together without any leftover parts.  The slow speeds all work properly now, it’s ready to shoot film.  I’ve been hesitant about doing this but it wasn’t as hard as I thought.  I found these great instructions that were really helpful:

http://tunnel13.com/blog/tag/leica-iiia/

http://tunnel13.com/blog/leica-iiia-cla-clean-the-slow-speed-escapement/

http://rick_oleson.tripod.com/index-155.html

Leica IIIa by Bryan Chernick, on Flickr

02Pilot

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Re: I just made/fixed ...
« Reply #214 on: December 31, 2017, 01:07:06 PM »
There's nothing particularly difficult about the Leica mechanics; as you found, they come apart and go back together relatively easily, as long as you pay attention to all the little parts and how they fit. There are, however, a few points to note. One is that there are adjustments that can be very fiddly to get exactly right (slow speed lever, shutter brake on the later models, curtain tension, to name a few). The second is the question of lubrication; Leica used a ridiculous number of different lubricants in these cameras, and while I've never tried to determine the properties of each, let alone replicate them (whale oil is hard to find these days), careful lubrication is important to maximize the life of the components. I've found that Breakfree CLP (a firearms lubricant) is a good general purpose oil, while molybdenum grease, clear synthetic all-purpose grease (Superlube), and synthetic automotive wheel bearing grease are useful in different areas.
Any man who can see what he wants to get on film will usually find some way to get it;
and a man who thinks his equipment is going to see for him is not going to get much of anything.


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Bryan

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Re: I just made/fixed ...
« Reply #215 on: December 31, 2017, 02:12:20 PM »
There's nothing particularly difficult about the Leica mechanics; as you found, they come apart and go back together relatively easily, as long as you pay attention to all the little parts and how they fit. There are, however, a few points to note. One is that there are adjustments that can be very fiddly to get exactly right (slow speed lever, shutter brake on the later models, curtain tension, to name a few). The second is the question of lubrication; Leica used a ridiculous number of different lubricants in these cameras, and while I've never tried to determine the properties of each, let alone replicate them (whale oil is hard to find these days), careful lubrication is important to maximize the life of the components. I've found that Breakfree CLP (a firearms lubricant) is a good general purpose oil, while molybdenum grease, clear synthetic all-purpose grease (Superlube), and synthetic automotive wheel bearing grease are useful in different areas.

I was careful to put the slow speed mechanism back together exactly how it came apart adding a small amount of grease to the knob.  I didn’t touch the curtains, they seem to be in good working order.  The curtains are something that I’m not comfortable messing with.  I started reading some of the article below and quickly decided not to touch them.  I used lithium grease and sewing machine oil (mineral oil), that’s what I have always used in my movie cameras and projectors. 

http://rick_oleson.tripod.com/leicashutter.pdf

02Pilot

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Re: I just made/fixed ...
« Reply #216 on: December 31, 2017, 02:30:58 PM »
I don't care for lithium grease, at least the ones I've tried, as they tend to separate. Mineral oil is OK as long as you're not using the camera in very cold temps. Everyone has their own preferences at this point, as the original options are long gone for the most part.
Any man who can see what he wants to get on film will usually find some way to get it;
and a man who thinks his equipment is going to see for him is not going to get much of anything.


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Bryan

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Re: I just made/fixed ...
« Reply #217 on: December 31, 2017, 06:23:38 PM »
I don't care for lithium grease, at least the ones I've tried, as they tend to separate. Mineral oil is OK as long as you're not using the camera in very cold temps. Everyone has their own preferences at this point, as the original options are long gone for the most part.

I have noticed that with the Lithium grease, I'll look into getting some of the lubricants you mentioned.  One thing I started thinking about after I got everything back together was lubricating the slow speed shaft where the brass speed adjuster comes in contact with it.  I assume that shaft rotates against the brass adjuster when using the slow speeds.  I didn't see anything about it in the instructions but it seems that would be a spot that could use some lubrication. 

Francois

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Re: I just made/fixed ...
« Reply #218 on: December 31, 2017, 10:28:13 PM »
I wonder if electronics grade white lithium grease is any better than the run of the mill car stuff?
I got some from a local electronics store and they claim it stays greasy and doesn't separate until fairly high temperatures.
I've used it to lube a focusing mechanism and it feels pretty good so far.
Francois

Film is the vinyl record of photography.

Bryan

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Re: I just made/fixed ...
« Reply #219 on: December 31, 2017, 11:44:35 PM »
I have noticed some separation in a tube that I have had for several years, one tube lasts a long time for what I use it for.  I have never noticed any problems in my projectors and they produce a lot of heat. 

02Pilot

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Re: I just made/fixed ...
« Reply #220 on: January 01, 2018, 12:57:23 AM »
I don't care for lithium grease, at least the ones I've tried, as they tend to separate. Mineral oil is OK as long as you're not using the camera in very cold temps. Everyone has their own preferences at this point, as the original options are long gone for the most part.

I have noticed that with the Lithium grease, I'll look into getting some of the lubricants you mentioned.  One thing I started thinking about after I got everything back together was lubricating the slow speed shaft where the brass speed adjuster comes in contact with it.  I assume that shaft rotates against the brass adjuster when using the slow speeds.  I didn't see anything about it in the instructions but it seems that would be a spot that could use some lubrication.

You're talking about where the shaft runs on the cam on the back of the slow speed dial, yes? If so, then yes, I think lubrication is called for (I'm not home right now or I'd check the Leica manual to confirm). IIRC, I applied a thin film of moly grease.
Any man who can see what he wants to get on film will usually find some way to get it;
and a man who thinks his equipment is going to see for him is not going to get much of anything.


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Pete_R

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Re: I just made/fixed ...
« Reply #221 on: January 01, 2018, 03:02:03 PM »
Ever since Bryan posted his negative copying setup (http://www.filmwasters.com/forum/index.php?topic=8655.msg121179#msg121179), I've been meaning to do something similar. I bought some bits ages ago but have only just got around to making what I had in mind. Here's the, more or less, finished item.



I started out with one of these



and joined the two racks together to make one longer one which I attached to the frame. The base, which would normally be screwed to a tripod head, has now become the movable carrier and I screwed the camera mount directly to it. Illumination is a simple LED light panel.

Results?

Same 35mm neg scanned on my Epson 4990 (left) and with the new setup (right) at 100%.



Whole image.



The lens I'm using is a Tamron 90mm. On its own it will do 1:2. With a x2 converter it will do 1:1. The above was shot with the converter. The lens can suffer from a strange flare. I've seen it before but only when used on my A7 as here. Initially it was very bad but by masking the light source all around the neg I can eliminate it. But I might try some alternative lenses.
"I've been loading films into spirals for so many years I can almost do it with my eyes shut."

Bryan

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Re: I just made/fixed ...
« Reply #222 on: January 01, 2018, 04:50:53 PM »
That’s a nice looking setup Peter, I like the rack setup for centering on the negative.  I found in addition to masking the negatives that you either need to scan in the dark or use bellows like my newest setup (link below).  Otherwise you can get reflections on the negative.  I use the macro zoom lens that came with my Olympus OM-D E-M5.  I use the macro setting for everything up to 6x6 negatives. 

http://www.filmwasters.com/forum/index.php?topic=8655.msg123458#msg123458
« Last Edit: January 01, 2018, 04:54:34 PM by Bryan »

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Re: I just made/fixed ...
« Reply #223 on: January 01, 2018, 06:18:37 PM »
That’s a nice looking setup Peter, I like the rack setup for centering on the negative.  I found in addition to masking the negatives that you either need to scan in the dark or use bellows like my newest setup (link below).  Otherwise you can get reflections on the negative.  I use the macro zoom lens that came with my Olympus OM-D E-M5.  I use the macro setting for everything up to 6x6 negatives. 

http://www.filmwasters.com/forum/index.php?topic=8655.msg123458#msg123458

I need to experiment a bit more. I'll try it with the room lights off to see if that helps.

Another issue I've found is I was getting banding across the image. It's something to do with the LED panel and the camera interacting. So I've switched to a small neg viewer as a light source. Not sure what sort of lamp is in it but it's got rid of the banding.

Have you scanned any colour neg with your setup Bryan? I've tried with no success so far. Can't get the colours correct. I setup a custom colour balance in the camera using some blank film and that very effectively removes the orange mask but I still get colour casts I've not been clever enough to remove. I tried importing a scan into Vuescan to use its custom settings for different film but that doesn't work for imported images. I'll have to do some Googling. I'm sure others have done this before.
"I've been loading films into spirals for so many years I can almost do it with my eyes shut."

Bryan

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Re: I just made/fixed ...
« Reply #224 on: January 01, 2018, 07:22:24 PM »
I also use a Circular Polarizing filter, that seemed to help with newton rings when I was using a glass plate to hold the negative flat.  That may help with the banding as well.  I use an iPad for the light source, If I was to use a led array I would make more separation from the light source and the negative to allow for better diffusion of the led lights.  Maybe add another piece of  translucent white plastic as well. 

I have not scanned color film with my setup, my lab does very nice scans. 

Francois

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Re: I just made/fixed ...
« Reply #225 on: January 01, 2018, 08:53:38 PM »
I had made a somewhat similar contraption a long time ago and was getting pretty good results with it.
On mine, the light source was far away from the negative which was held by a film holder from my enlarger. The light source was an incandescent bulb that went through a diffuser.
I found that for good results I needed surprisingly to underexpose my images by some margin, but I suspect that doing an HDR treatment would give the best results.
To remove the color cast on negatives, I would take the photo with the white balance set for the light source, import into photoshop, go to the levels menu and select a part of the clear negative using the proper eyedropper. That works pretty good. Then I invert the image.
Francois

Film is the vinyl record of photography.

Pete_R

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Re: I just made/fixed ...
« Reply #226 on: January 01, 2018, 09:20:14 PM »
Reading around what other people do, it seems manually adjusting the curves is the preferred method - I was trying to get the auto colour balance to fix things. So I've tried again. I think adjusting the colour balance of the camera to eliminate the mask is what I'll stick to as I only use one colour film (Ektar) so I only need to do that once. Twiddling the curves got me pretty close but I was surprised how much I needed to adjust the individual colours. This image is one I've always had problems getting right and this is the best I've ever done with it so I must be getting somewhere. Still needs a tweak though.



Edit: picture updated with better version.
« Last Edit: January 02, 2018, 05:23:14 PM by PeterR »
"I've been loading films into spirals for so many years I can almost do it with my eyes shut."

Francois

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Re: I just made/fixed ...
« Reply #227 on: January 01, 2018, 10:44:56 PM »
The fun thing with curves is that you can save them. You probably can apply the same one to most negatives that have the same film.
Francois

Film is the vinyl record of photography.

Francois

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Re: I just made/fixed ...
« Reply #228 on: January 23, 2018, 06:15:27 PM »
OK. We had a power failure this morning. So after reading and playing the uke for a while, I decided to tackle a job I've been meaning to do for so long I don't dare say it in public.
Thing is, I've got this run of the mill Nikkor 50mm f/1.8 that was desperately needing a lube job. When I say it was really needing it, you could feel the helices rub metal on metal.
I must say I was pretty impressed with the way the lens is made. You just loosen a grub screw on the side to remove the front of the lens. Then three screws and you're in.
But putting both helices in the right position was the usual nightmare. Took a couple of hours but now the lens is buttery smooth.
Francois

Film is the vinyl record of photography.

cs1

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Re: I just made/fixed ...
« Reply #229 on: February 23, 2018, 10:44:14 PM »
I made a Shutter Speed Tester from an Arduino Uno, a light sensor module, and an LCD. It's still WIP but the proof of concept seems to work. I'd like to put it into a smaller package (Arduino Nano + sensor + LCD + battery in a single case) at some point so that I can carry it anywhere (garage sales? used camera sales fair?). Also, I'd like to switch to IR instead of visible light but I couldn't get the necessary components in time. I still have plenty of space on the LCD so I'm currently thinking about what more information would be useful to have on there. I'd also like to add a button to reset the test.

P. S.: I know that this is neither a particularly new nor a particularly clever idea, more talented people have built better setups but I wanted to try it by myself and it was great fun. :)

Francois

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Re: I just made/fixed ...
« Reply #230 on: February 24, 2018, 02:19:26 PM »
Now that is sweet.
You could make it a two part system with a sensor pack and a display pack that would contain the batteries and the Arduino. That way if you need to change the sensors you don't need to take the whole thing apart.
Francois

Film is the vinyl record of photography.

cs1

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Re: I just made/fixed ...
« Reply #231 on: February 25, 2018, 10:38:22 AM »
Yes, good idea. All of the digital sensors behave the same, making them interchangable shouldn't be too difficult. I'll keep you posted.

ManuelL

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Re: I just made/fixed ...
« Reply #232 on: March 02, 2018, 06:10:33 PM »
Just (semi) fixed the broken focus dial of this little Contax I had inherited from my aunt some time ago. When I opened up the dial a tiny spring and some tiny, tiny parts jumped out at me (WHY, OH WHY !!!). After I finally found the parts (WHY do they have to use parts that are 1 mm or smaller?....) I glued the contact back into the dial know and put the spring and tiny ball back where I thought they belong. After re-attaching the dial, I turned it (scrchh!!!) and it was broken again. I think the little spring and ball did the same thing as the had done in the first place and pulled off the concact from the dial. Now I put everything back together without the spring and ball. Seems to work, except the dial is not clicking any more. I am just running some test rolls through the camera, hope they turn out ok. Will think of a solution to get the clickiness back.

The camera itself fees a bit stylish for me, but I guess I'll get used to it.  :)


Contax by Manuel Lion

Kai-san

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Re: I just made/fixed ...
« Reply #233 on: March 02, 2018, 06:28:27 PM »
You're a lucky guy if it works, the Contax T2 sells for silly prices at the moment. I've been looking at the first one, the T which is a "folder" like the Minox'es. It's manual focus, so I'm afraid it might be a bit fiddly given the tiny size.
Kai


If you want to change your photographs, you need to change cameras.

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Bryan

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Re: I just made/fixed ...
« Reply #234 on: March 02, 2018, 07:12:05 PM »
You're a lucky guy if it works, the Contax T2 sells for silly prices at the moment. I've been looking at the first one, the T which is a "folder" like the Minox'es. It's manual focus, so I'm afraid it might be a bit fiddly given the tiny size.

I have the T, it's a nice rangefinder and the lens, the same one as Manuel's camera, is very nice.  It's also very small and fits nicely in your pocket.  The rangefinder is not great but my viewfinder is a bit scratched.  The one thing I don't like about it is that you have to reach awkwardly around the lens door from underneath to focus it.  Otherwise you block the viewfinder or rangefinder window.

Contax T by Bryan Chernick, on Flickr

cs1

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Re: I just made/fixed ...
« Reply #235 on: March 17, 2018, 11:08:28 AM »
I've finished building the Shutter Tester and I just put up the source code and schematics on github so that people can build it themselves. If you're interested, have a look here:

https://github.com/c-s-1/shutter-tester

Francois

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Re: I just made/fixed ...
« Reply #236 on: March 17, 2018, 01:04:56 PM »
I'm going to take a look. Could be an interesting build. :)
Francois

Film is the vinyl record of photography.

cs1

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Re: I just made/fixed ...
« Reply #237 on: March 17, 2018, 03:55:08 PM »
If you have questions or suggestions, please let me know, I'd be happy to help if I can. Patches are welcome, too. :)

Francois

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Re: I just made/fixed ...
« Reply #238 on: March 17, 2018, 07:52:17 PM »
To increase the high speed precision you could make a slit mask for the sensor. A narrow strip is more likely to record a shorter moment in time.
The thing with focal plane shutters is that it's the width of the slit that determines the exposure. At the point where the shutter gap is the same as the size of the sensor you won't be able to get a good measurement.

To know if this is right, check it against a regular in lens shutter.
Francois

Film is the vinyl record of photography.

cs1

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Re: I just made/fixed ...
« Reply #239 on: March 17, 2018, 08:13:18 PM »
I agree, there's a lot of room for improvement. It's probably even a good idea to work with several sensors in a row. I feel version 0.2 of this contraption taking shape in my mind. :) Thanks for the feedback.

Francois

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Re: I just made/fixed ...
« Reply #240 on: March 17, 2018, 09:13:41 PM »
I don't really see how a series of sensors would improve anything. You don't need more than one at the start and one at the end of the travel.
Having two sensors would indicate is the travel speed is constant.
Personally, I'd concentrate on making the single sensor version as reliable as possible first and then add a function for a second one (or just make the sensor block in a way that you can reverse it to check the other end of the curtain travel.
Francois

Film is the vinyl record of photography.

cs1

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Re: I just made/fixed ...
« Reply #241 on: March 17, 2018, 09:55:31 PM »
I need to give it some more thought. I'm not entirely sure that a slit mask would be necessary. I tested the shutter of a Canon F-1 which has a metal foil curtain shutter and I also tested several other cameras and they all give me plausible results. I don't know if I own a camera with a focal plane shutter (or maybe I hit the "non native speaker language barrier" and mistake the focal plane shutter for something else). Anyhow, I think that the software needs some more work. I work with interrupts which should give me a reasonably precise timing, assuming that the sensor module doesn't add any delays. Since I don't know if this is the case, I need to figure out if the delays for starting to detect IR and stopping to detect it are the same; if they aren't the same, this would have to be factored into the measurement. So I guess that some sort of calibration routine would be interesting. However, this is only feasible if the Arduino can actually turn on and off the IR emitter by itself. Then I could turn on the IR emitter, memorise the timestamp and subtract it from the timestamp when the IR sensor signals the detection. This should give me the delay of the sensor module. Then do the same when turning the IR emitter off. This would give me reference values that I could use to get a more precise measurement. Maybe this would help with measuring the faster times (less than 1/500s) for which I don't know if they are accurately measured at the moment.

I'm afraid that I'm going very much off topic so I'll open a separate thread as soon as I've got more news on this project. If you build this thing, François, please let me know, I'm very much interested in your thoughts.

Francois

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Re: I just made/fixed ...
« Reply #242 on: March 18, 2018, 01:32:02 PM »
The sensor specs should give you the minimum exposure and reaction delay.
I was thinking last night and was wondering if there could be some additional precision possible by glueing two sensors together at a known width and using the change in luminosity to measure the speed.

Also, I know there are both two pronged and three pronged phototransistors. The three pronged ones are usually much faster to react than the two pronged ones.
Francois

Film is the vinyl record of photography.

cs1

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Re: I just made/fixed ...
« Reply #243 on: March 18, 2018, 04:54:48 PM »
Good point. I'll quickly move my answer to a new thread to keep this thread "clean".

Sandeha Lynch

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Re: I just made/fixed ...
« Reply #244 on: April 09, 2018, 03:46:56 PM »
Happy to see that this thread is staying alive with everybody's good works.

Just finished a little conversion to make a Pinorama.  The frame measures 28x60. 

The body arrived with an unfixable broken speed selector so it was ripe for conversion.  After two years on the shelf, and with a few parts stripped off for other projects, the remains of the body was almost queued up for recycling, but then I remembered that WPPD is coming up so ...

The camera to the right is an F.X2 in perfect condition and is shown for comparison.


IMGP8811a by Sandeha Lynch, on Flickr


IMGP8813a by Sandeha Lynch, on Flickr

Waiting on the weather and perhaps some Fuji Acros.  I have six rolls left, dated 2012.
« Last Edit: April 09, 2018, 10:32:46 PM by Sandeha Lynch »

Bryan

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Re: I just made/fixed ...
« Reply #245 on: April 09, 2018, 04:29:40 PM »
Nice job Sandeha!  Did you have to carve away at more than just the film mask to get that wide?  It looks like some of the internal stuff was cut away like the mirror mechanism.  Now you have me thinking about what camera I can cut away at. 

Sandeha Lynch

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Re: I just made/fixed ...
« Reply #246 on: April 09, 2018, 04:50:21 PM »
Brian, yes I had to cut away the sides of the chamber.  I cut as far as was practical with a hacksaw and then crosswise using a Dremel wheel - by the time I was done the line of sight was more than clear.  After peeling the curtains away from the rollers I ripped away much of the insides with pliers, and then stuffed the various holes with darkcloth and sealer.  There was little worth saving from the guts.  My guess is that the body form of the Praktica is particularly suitable as it's really a very wide camera.  I don't know that many would yield a negative length of 60mm.  At two wheel-turns per frame I'm hoping I'll get a decently spaced 15 shots.

EDIT:  Quick extra point.  I ran a roll through and then found there were considerable internal reflections.  I glued some darkcloth sections into the body to completely cover the internal area.  Problem solved.  Also found that it makes 16 clear frames on a 36 roll, with very even spacing - 3 shots in a standard neg storage sleeve.  The slight downside is that the body cap puts the focal length at 45mm, which is a bit long for a wide angled view (if that's what you like).  I have a 6x9 that is 45mm, so that is wide, but on this frame it's just a segment of that.  0.25mm pinhole in brass from www.vist.lt or his eBay shop.
« Last Edit: April 21, 2018, 11:37:32 AM by Sandeha Lynch »

Francois

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Re: I just made/fixed ...
« Reply #247 on: April 09, 2018, 09:19:59 PM »
Now that is interesting...
I wonder if my old Praktica L would be a good choice? Or my broken Chinon...
Francois

Film is the vinyl record of photography.

Sandeha Lynch

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Re: I just made/fixed ...
« Reply #248 on: April 09, 2018, 10:40:52 PM »
Have a look in the back Francois.  This Praktica has that metal plate for a film gate which is easy to remove and cut, yet still strong enough when it's back in place, and being a cloth shutter it's really only curtains and one roller that need to come out.  Then all you need is to ensure that the winder and rewind button still function OK, plus the rewind lever itself.

Francois

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Re: I just made/fixed ...
« Reply #249 on: April 10, 2018, 02:39:28 PM »
I checked my praktika last night and it has a vertical metal shutter that relies on a weird mechanical timer. I guess I'll have a bit of engineering to do.

Did you completely remove the screw mount on yours?
Francois

Film is the vinyl record of photography.