Topic: A bit more on camera makers - from FeatureShoot

[Sandeha Lynch]

Don't know how FeatureShoot found me, but there are a few folks that I know in this collection. And interesting bits.

https://www.featureshoot.com/2020/12/15-diy-cameras-thatll-blow-your-mind/

[Kai-san]

Some wonderful stuff here, I love it when people re-use parts from broken cameras to create new working cameras. I've been wondering if it's possible to revive cameras from the 60's and 70's with electronic shutters, or maybe just re-use the shutter and lens. I assume many of these are dead due to electronics failure, and that the shutters may be OK. It should be possible to make an electronic circuit to control the shutter speeds. The problem might be to get reliable data on these old shutters.

[Francois]

I figure that they could probably be easily revived using an Arduino.
In the end, it's just two electromagnets with a timer...

[Kai-san]

I would make it as simple as possible with a CMOS timer, an RC network and a rotary switch. For a handheld camera, five shutter speeds between 1/30s and 1/500s should suffice. It could run on a 3V battery provided the shutter will open at 2V.

[Pete_R]

Depends on what shutters you're referring to. Many 'electronic' shutters are actually more mechanical than electronic with just a form of electronic timing which is usually an electro magnet to hold the shutter open for the required time. They still need mechanically cocking and triggering.

[Kai-san]

I assumed they would need to be cocked mechanically, but the goal must be to replace the dead circuitry that was originally built into the camera. In those days it would have been discreet components that should be possible to replace with ICs. Finding the schematics for these cameras will be difficult, so some practical prototyping would be required.

[Pete_R]

If you're thinking of just resurrecting old cameras then the electronics are probably the least likely cause of failures. Yes, they do happen, but 99% of the problems I see are mechanical. I thought you were thinking of using the shutters in other, custom built, cameras.

[Kai-san]

Using lenses and shutters in a custom built camera is definitely an option. I don't know if Konicas are especially prone to electronics failure, but I've got four of them that are completely dead even with battery adapters to obtain correct voltage. Problem is that they are so nice looking that it would be a shame to rip them apart to use the lenses.

[Francois]

I know Konicas are really picky when it comes to voltage.
I'm ready to bet that most of them have a corroded wire inside and not much else stopping them.
I have a T3 Autoreflex that needs a good CLA. With it I found that even the WeinCells give improper exposure values when compared to Mercury. The voltage difference is enough to sway the meter off by more than a couple of stops.

[Kai-san]

You could be right about wire connections and bad soldering, the problem is to find them. I've also heard that some battery adapters are too short to make proper connections, some have successfully put aluminium foil into the battery compartment to make contact. I'm retiring from working life on Monday, so in the new year I will have more time to experiment. 

[Francois]

I don't know if it's related in some way but I noticed on some old exposure meters that use Mercury cells that the corrosion seems to usually occur directly at the battery connection.

[John Robison]

Just wish someone would bring back a really basic 35mm SLR like a Ricoh KR-5, but without the meter. Don’t reinvent the wheel either, just copy the camera, part for part. No meter, then no problem with the battery. Include in the box a cardboard exposure calculator.
The one extra expense, premium item in the camera would be a glass penta prism and really good bright focusing screen and diopter adjustable eyepiece. For through the lens focusing you just GOT to have the best viewing available.
When I sold cameras in the 70,s and customers had problems with unsharp pictures 50% was blur from camera movement and the other 50% was because they couldn’t see the screen well enough to focus accurately.

[Kai-san]

I totally agree John, the simpler the better. There are quite a few old SLRs that can be used without a battery, but adjustable diopters came rather too late for mechanical cameras. My favourite meterless 135 SLR is the Exakta Varex IIa, it has a rectangular viewfinder big enough to use with glasses. In addition you can get a WLF for it. And the mechanics are of Leica quality according to those who repair them.
If there weren't so many different viewfinder sizes on older cameras, an add-on variable diopter could have been the solution.
The brand with the darkest viewfinder I've ever tried is Konica. I had a T4 for a while, but I sold it on pretty quick. I couldn't get a diopter for it either.

[Francois]

I had a Praktica and this was pretty dim...
I think the quality was pretty dim too as the shutter let go quite rapidly. But I don't know how the previous owner abused it.

[John Robison]

I should also note that screen brightness is not the only factor in focusing ease. I have a Olympus Pen F from about 1964 and the plain matte screen although dimmer than modern screens has the right ‘texture’ and especially good CONTRAST, so that I find focusing easy. To emphasize this point, modern autofocus SLR’s often had very bright screens that were just lousy for manual focus because they weren’t optimized for manual focus.
One of the best SLR focusing screens was the old Leicaflex Standard, the one with the external meter eye on the prism housing. It was fantastic (and breathtakingly expensive no doubt).

[Kai-san]

Very true, I've always liked cameras with a splitscreen viewfinder. Micro raster is also a good solution except when it's getting dark. That's where the Contax RX is very handy, it's got manual focus, but it's passive autofocus tells you when you're in focus.
As for seeing any new manual SLRs on the market, I guess that's not very likely to happen. Nikon is still making the FM10, but it will not work without batteries. Of the "newer" SLRs that I know of that will work without batteries is the Contax S2 and Nikon FM3A. They both cost a pretty penny. Perhaps the best thing is to support the people that still repair old cameras and keep them busy.

[jharr]

I know it's been a while and I hate to do it, but I feel that I must call a "flower foul" on this thread. For those not familiar, this is what happens when a thread turns into a strictly technical discussion and has no photos. Think of it as an 'urban beautification' project for Filmwasters!

F2-Eterna-039sm by James Harr, on Flickr

[Indofunk]

Well done James! I apologize that I haven't been policing the flower fouls well enough lately, but this one is well called!