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Forum: Photographic Equipment for Sale
03-31-2024, 04:04 PM
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You have a fantastic price on the Tower 26, I might add it is almost GIFT at that price. That is clearly a collectors Item , someone ought to wake up and snap it up.
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Forum: Film SLRs and Compact Film Cameras
01-28-2024, 06:46 AM
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Just got done remanufacturing an opening shutter and getting ready to re attach it here is a picture. This is not for the feign of heart. By the way if you do this and mess up your camera don't blame me. But you can ask me for advice any time.
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Forum: Pentax K-S1 & K-S2
11-11-2023, 01:25 PM
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This article gives lens chronology view
Lens glossary - knowing more about Pentax lenses ? PENTAX - Official Store
And this the camera mount view
The Evolution of the Pentax K-mount - Articles and Tips | PentaxForums.com
in essence the k mount started quite naked and gradually contacts etc were added to automate aperture/exposure and focus...
A camera with the 7 lens mount contacts and the 2 inside electronic ones is quite universal, but might need camera to be on the latest firmware for some recent lenses.
On digital cameras there are 2 major steps:
- electronic focus motors supported from K10D (almost all digital cameras, except earliest)
- electronic aperture control (latest 50% or so digital cameras , K-3 , K-50 KS-1 or later)
Hence the KS-1 supports even the most modern lenses with electronic aperture control, like Pentax K-S1 and HD Pentax-DA 55-300mm F4.5-6.3 ED PLM WR RE - Compatibility | PentaxForums.com so you are on safe side...but note the firmware notice.
If you need Software Downloads here
Older lenses will work also, but might be restricted as older lenses with manual focus or manual aperture control, as typical for their generation.
M or K lenses are manual
With an A in the name, auto exposure aperture is ok.
Autofocus came later... with F lenses or anything newer
Note also:
FA is for fullframe K1 or film camera sensor sizes , will work also on aps-c
DA is for smaller aps-c format only.
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Forum: Vintage Cameras and Equipment
10-29-2023, 04:43 PM
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Hello,
As some of you know, I also restore and collect airbrushes. Airbrushes are used today for a huge variety of purposes. From illustration artists, to scale modelers like me, automotive customization, make up industry, even scientific research and specialty medical fields.
But did you know that initially, one of the most common uses of the airbrush was to retouch and colorize photographs? That was the photoshop of the late 19th century and most of the 20th Century.
I am very active in another online forum dedicated to airbrushes. Over there we discuss in details the use, help and support, history of these tools plus my restoration adventures.
But this one is very special and I want to share with my Pentax family. Here is a X-post from that other forum. There is some "airbrush jargon" so please let me know if anything needs clarification.
Century old Thayer & Chandler Model A
I'm very excited to present this. I've been restoring vintage cameras (and other stuff) for years and for me there is always a magic threshold when you are holding any artifact that is around 100 years old or more. As a historian buff I can't help but to think in all the major world events that have happened since "this was built" and also personal family stuff like "Grandpa was a teenager when this or that happened", or "my mother was 1 1/2 years old when Pearl Harbor..." stuff like that.
As you know, I've been restoring and working with airbrushes for a while now. Many times it is just a cleanup of a not so old but neglected unit, other times it may be something a bit more special. But there is always a satisfaction of bringing something back to life.
This is one of those very special cases.
Brief history:
In the mid 19th Century, the Thayer & Chandler Company was established primarily as an arts and crafts supplier. When Charles Burdick patented what we call now the Internal Mix airbrush in 1891, Thayer & Chandler quickly licensed it and started production. Many improvements were quickly patented, most if not all from the mind of Olaus Wold who worked for Thayer & Chandler before creating his own airbrush company. At the turn of the 20th Century, as early as 1904-05, the airbrush was pretty much recognizable as what we know today. Thayer and Chandler named it the "Model A". Their airbrush business grew and was so successful that by the second half of the 20th Century they had dropped from other businesses.
The Model A had an impressive production run of essentially all the 20th century.
Not surprisingly, improvements and changes were constantly been introduced. Some were small, some were major, but all trying to keep the product ahead of the competition.
At a very High Level, we can identify 3 major changes in the body of the Model A:
1. Start to ~1925. Early body design: What we know today as the nozzle head was part of the body.
2. ~1925 to the mid 1960's. The head where the nozzle goes is a separate part from the body.
3. ~Mid 1960's to the end of production (late 90s?). The original cylindrical body was changed to a more stylized tapered towards the front body.
Countless of other changes made their way into production thru the years like materials, handles, cosmetic changes, etc.
My Specimen:
A few months ago I was able to score an early body Model A. Took me a long time to finally be able to work on it.
The case has a seal type sticker that says "Thayer and Chandler Chicago 50 YEARS OF SERVICE" I am still researching on that but I've seen others online. Maybe a gift for an employee?
Consulting with Dave (our spiritual Leader and airbrush history Authority), this type of case was used until the early to mid 1930s.
The airbrush is a fixed head model A, indicating it was made no later than 1925 or the mid 1920s. So it is at least 98 years old at the time of this writing (Oct. '23).
It put quite a fight to be disassembled. Parts were really stuck and seized. Had to use some PB Blaster penetrating oil and considerable (but careful) force to get it to cooperate.
The all important nozzle shows some wear, but seems to be in good shape.
Among other things, the needle needed some help. Picture from my cheap desk microscope.
Except from removing the nozzle, every other part was disassembled including the air valve. Each and every part then became its own individual restoration project thru the course of many weeks with the constant thought of "This is 100 years old. Take it VERY easy, don't overdo it". i.e. "DON'T DO ANYTHING STUPID!" You stupid! :)
Which I almost did. A tiny part went flying off the workbench and took many tense minutes to locate. ��
A few weeks later it was looking like this:
The case and the included color cup will eventually be addressed as well.
At this point, it would be a matter of simply put it together, test it and live happily ever after, Right?
Well, there was an issue here. While it works, the needle did not protrude from the nozzle as expected.
Took it apart and rechecked everything several times. At the end (again with Dave's guidance), the needle happened to be the wrong one. It looks suspiciously similar to a Model AA needle. It has no markings like Badger needles so I suspect it is a T&C needle, just the wrong type. I found in my spares a proper Model A needle, that by coincidence had a similar bent at the tip but a bit worse. Repaired it to the best of my abilities. Not perfect but almost there.
The handle is most likely not original to the brush. Not only the style is later than this timeframe, but it fits too tight to the needle tube and the threads are smaller than the body. But it kind of works.
The end result:
May I humbly present the oldest airbrush in my collection, pushing a Century.
If you still doubt it works... :)
https://youtu.be/x5VWi6rvrNk?si=9lYlU6ScPa7SjnuI
Now it can live happily ever after...
I'm impressed! Did I mention this is about 100 years old?
Special thanks to Dave for his guidance.
As usual, I hope you like and approve.
As always, your comments and questions are appreciated.
Thanks,
Ismael
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Forum: Film SLRs and Compact Film Cameras
07-28-2023, 06:14 AM
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Good question but hard to answer. It depends on lots of circumstances, e.g. experience of the technician, whether professional gear like a calibrated shutter speed tester is available, whether circuit boards for eventually needed replacements of log compression/expansion have already been prepared, whether the board revision is an already familiar one, etc.
Let's say you get an Electro Spotmatic with a broken CdS cell, like I had. If nothing else is wrong and all the mechanics are fine, diagnosis could be done in half an hour. But then there are a lot of steps even if the process has been streamlined:
- disassemble camera top and bottom
- remove CdS assembly and desolder CdS cells
- replace, glue, and solder new CdS cells and resistor(s)
- remove PCB, desolder log compression diode; optionally desolder discharge network
- if wires break (quite likely), rework the solder joints to the camera connector
- solder new log compression (and optionally discharge) networks on daughterboards and solder them into the PCB
- reinstall CdS assembly
- reinstall PCB
- go through calibration procedure
- fully assemble the camera
- final testing
Even if everything is perfectly prepared, nothing unexpected happens, and all the necessary tools are available, I'd say it is at least one to two full days of work, not counting time for setting of glue, etc. But more importantly, usually something unexpected *will* happen, and the effort can explode by multiple times. Working on such old and unknown stuff is risky.
No, I'm not seriously considering that. Also, I don't think the interest is significant. I have not yet gotten a single inquiry to this end.
A paid repair on component level would be very expensive even in the best case and due to all the unknowns involved it could quickly become a very bad deal for all involved parties.
It could not be justified by the resale value of these cameras, I think, especially since I don't think collectors are that interested in their cameras actually working (are they? I'm more a camera user than a collector myself, so I'm not sure). Repairing such a camera is really a labor of love.
That said, it would be great if people offering camera repair services would take on repairing these interesting cameras, understanding and communicating the risks involved. I'd be happy to offer any information I found and any design I came up with while reverse engineering the Electro Spotmatic.
---------- Post added 07-28-23 at 06:20 AM ----------
That sounds exciting. Don't hesitate to contact me for any info that might not be found in the videos!
---------- Post added 07-28-23 at 06:25 AM ----------
Thank you for the kind words. The preservation of knowledge about these fascinating cameras was my main motivation for investing all the time to make the videos.
The Electro Spotmatic is quite special. It marks the end of an era (that of analog, discrete component electronics) and at the same time the beginning of another era (that of automated, electronically controlled SLR cameras, and more broadly that of consumer devices with sophisticated, miniaturized electronics).
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Forum: Film SLRs and Compact Film Cameras
07-27-2023, 02:14 AM
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Dear Pentax fans,
my repair of the (second) Pentax Electro Spotmatic is finally finished. The full series of videos with all the explanations about how this camera works and how to test/repair/calibrate it is on YouTube:
Pentax Electro Spotmatic - YouTube
I hope this will some day be useful to someone working on an Electro Spotmatic!
best regards
Edwin
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Forum: Film SLRs and Compact Film Cameras
05-04-2023, 02:58 PM
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Dear Pentax enthusiasts!
Last year, my father bought two Pentax Electro Spotmatics. (The prototype model that was only sold in Japan for one year 1971 to 1972.)
Since neither of the cameras worked, and there is no maintenance information available, I spent a lot of time reverse-engineering the cameras and ultimately repairing the first of them. I am now creating a series of YouTube videos in which I publish what I have found out, including full schematics and how to repair and calibrate these cameras.
The first video is now out. In this first part, I discuss mostly disassembly and the (quite elaborate) power supply circuitry:
Youtu.be
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src="https://www.youtube.com/embed/GrQI07X9Zi0?controls=1" allowfullscreen>
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Please tell me, if you are interested in this kind of information. I have a lot of additional information, design files, etc. for people who want to work on their Electro Spotmatics themselves.
best regards
Edwin
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Forum: Vintage Cameras and Equipment
01-22-2022, 01:26 PM
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Hello,
I don't do commercial or customer's work. All my work is usually on my own equipment, but occasionally, friends or family may bring something to look at.
Fellow forum member Sam (Sam_I_am) accuses me of getting him back into vintage cameras. I'm guilty as charged! :)
The external clip on meter for his Minolta SR-1 was not working. We exchanged a few emails with some troubleshooting ideas but at the end, it landed on my bench.
There was corrosion from a leftover battery and the battery contact lost its connection. The problem is it is in a quite tricky position. Hard to reach and not much space.
It was cleaned the best I could and resoldered a short piece of wire to restore the connection.
Long story short, it now works :)
It will soon be reunited with its mothership.
Thanks,
Ismael
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Forum: Film SLRs and Compact Film Cameras
12-28-2021, 09:53 AM
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Happy Holiday season to all :)
This happy Asahiflex I says hi.
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Forum: Monthly Photo Contests
12-08-2021, 11:06 AM
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In a time when we are very divided over many things, this shows a form of unity without specifying gender, race, etc.
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Forum: Sold Items
09-14-2021, 11:35 PM
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Forum: Weekly Photo Challenges
07-22-2021, 05:18 PM
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Hi Mom and Dad
how do I look on the first day of the new job ?
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Forum: Repairs and Warranty Service
07-13-2021, 05:37 PM
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I would have Zero issues soldering a lever extension on there. My question is how long must it be ?
I would also ignore the rest of the Dremel damage short of a Sharpe touch up , and a bit of smoothing out the damaged area.
If you can take the circular ring/part off and ship it to me I'm willing to help.
I won't charge a dime .....PM me if interested.
FWIW....I have access to a full machine and metal shop and have brazed / welded / soldered just about anything imaginable. And if I cannot do it satisfactory two shop members are also jewelers!
I can just imagine this lens ingloriously perched on the snout of some Canonistas Bastard Camera....:mad:
---------- Post added 07-13-21 at 18:10 ----------
I'm actually thinking three pieces. 2 pieces of shim stock sandwiching the lever extension !
Precise work but easily do-able.
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Forum: Photo Critique
05-10-2021, 08:46 AM
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yes, two shots combined in photoshop
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Forum: Post Your Photos!
05-01-2021, 08:59 AM
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My son is now studying in another country and I really miss him.
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Forum: General Talk
02-23-2020, 09:25 AM
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Quick and Dirty Beauty Shots. Our Thin Mints went to the Service Member donation box this year. I don't remember asking the Girl Scout to do that, but OK. This feels easier to handle than I remember the D FA* was.
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Forum: Sold Items
02-21-2020, 01:33 PM
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The holy grail of macro lenses and it's still here??? Don't people know what this lens is? Or that it's better to use Manual focus for macros?
Bumping it to the top.
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Forum: Sold Items
11-14-2019, 06:26 AM
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Forum: Sold Items
11-11-2019, 10:33 PM
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Great shots at VIR!
This is a fantastic lens. Whomever picks this up will not be disappointed. GLWS!
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Forum: Pentax SLR Lens Discussion
11-09-2019, 10:32 PM
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Ricoh has a series of talks at their Shinjuku Tokyo and Osaka locations in the month of November to commemorate the 100 year anniversary. You can see a list of them here.
PENTAX 100???? | RICOH IMAGING
I decided to go along to a talk about the FA Limiteds by Kazuo Ikenaga (池永一夫). Ikenaga-san is now retired but was working there at the time these lenses were developed and is an enthusiastic user of them now, with his K-1 II. He gave a very interesting inside story of their development, and also a lens-by-lens description of their unique characteristics.
I’m afraid I didn’t take any photos at the event, but here is an image from the Ricoh Imaging Square Twitter.
????????????? (@RicohImagingSQ) on Twitter
As a big fan of the FA 77mm, I found this a very interesting story and here is an account of what was said. There may be some points I forgot between listening and writing, but it should be pretty accurate. This is going to be a long post.
The concept of the FA limiteds
In the late 90s Pentax was introducing a range of smaller cameras like the MZ-3 and MZ-5, and some people in the company felt they didn’t have the quality small lenses to go with them. They conceived the principles behind the FA Limited series.
- The design should give a soft but precise rendering. For example, hair should look like it is soft, not like hard strands.
- The filter thread should be 49mm.
- The aperture should be faster than f2.
- The design is of high-quality aluminium.
- As soon as you pull the lens cap off, the lens should be ready to shoot, without needing a separate action to attach a hood.
Overcoming internal sceptism
The proposal to make these lenses met with significant scepticism and opposition in the company. The Sales department was not at all sure that they would sell. They believed that Pentax was known for more value-oriented lenses, and that customers would not see the value of such small yet expensive lenses.
This resulted in the original plan of a trio of lenses to be scaled down (or rather slowed down) to one at a time. When the 43mm came out, they faced pressure to keep the cost under 70,000 yen, which was very tough. Fortunately, the 43mm sold better than expected. With their concept validated, they were able to release the 77mm and 31mm at two-year intervals and the price was allowed to go higher.
To reduce the initial costs and make the project feasible, a decision was made not to invest in the machinery to manufacture the lenses in a fully automatic way, but instead to machine the parts in a more manual way. This allowed them to release the lenses in the first place, but prevented them from reducing costs as they scaled up production subsequently.
The unconventional focal lengths
What has become the convention for focal lengths used by most companies was derived from what Leica made, but beyond that there was little justification for using those focal lengths. So the designers decided to free themselves from that constraint.
The first lens to be made was the FA 43mm. The intention was to make a classic normal lens to start with, and 43mm was chosen as the optimal focal length to achieve their design goals - faster than f2 and with a filter diameter of 49mm. There was a precedent for forty-something lenses from old rangefinders, and people had found that useful as their only lens. The fact that 43mm was the diagonal of 35mm film frame was not a principle that informed the design. However, they ended up using that coincidence as a marketing narrative when sales felt they needed to justify the unconventional choice.
A similar approach led to 77mm being chosen for the next lens. It sounds like the 77mm was a real technical feat at the time, especially the coating. For the 31mm they must have relaxed the filter diameter requirement.
Unique approach to design and evaluation
As they developed the lenses, they were advised by a famous photographer, the late Shoji Otake. The common practice at the time was to use to use computer aided design and evaluate using test charts. They rejected that methodology for the Limited lenses and instead used a painstaking method of human evaluation of prints. This is understandably a very slow way of developing lenses.
They invested in an expensive, state-of-the-art printing system from Fujifilm. Using the images produced, prototypes with different designs and coatings were evaluated. When they started this practice, the designers were not always able to see the differences, but Otake-sensei could immediately see the significant areas and told them where to look. Once they developed the ability to see the differences, they became skilled in the art of evaluating images themselves. Ikenaga-san commented how much they felt their own eyes improving by being part of this process.
For each lens they made a description of what it should be able to do. For example, with the FA 77mm, they wanted to create a lens that suppressed flare to to avoid washed out photographs. They defined this as being able to depict the glint of a white button on a white shirt. Then they went about the process until they achieved it, and this is why the ghostless coating was applied.
Differences in the concept of the DA Limiteds
Although the DA Limited series has some similarities, there were some different decisions made about the scope of that series. While the FA Limiteds were deliberately clustered close to normal focal length on 35mm film, the DA Limited series was supposed to go from true wide-angle to telephoto on APS-C. Also the DA Limiteds are slower than f2.
There was some talk about the DA Limited series in this presentation, but it didn’t go into as much detail about the design story as the FA Limiteds. He did talk about his personal favorites, which are the 15mm and 35mm macro. He also expressed his opinion that the DA 20-40 should be considered more like a prime - a normal with a bit of scope for adjustment. In fact, he seems to be a believer that primes instill better photographic practice.
Close focus ability
The designers took a lot more care about close focus ability than I had realized. The three lenses discussed here were the DA 15mm, the DA 35 macro and the FA 77.
The FA 77 has some kind special mechanism in the design that engages around f2.4 to allow better close focus performance when stopped down. Ikenaga-san mentioned you can feel a little click there if you use the aperture ring, but I can’t detect it on mine. In any case he strongly recommends stopping down to f2.5 for the best close focus performance with that lens.
When designing the DA 35mm, they did not start out with the intention of designing a macro. The original intention was to make a more general purpose normal lens for APS-C, but they ended up designating it as a macro eventually.
Left me with a strong desire for an FA 31mm
That basically all that I remember form the talk. It was pretty interesting overall. After doing a quick search to check some information, I found that Ricoh has an article by Ikenaga-san on their website (in Japanese). It contains a lot of the same things he said in the presentations, but in talk he said much more about the development story.
?2? ?????????? FA Limited??????????????/ Beautiful Photo-life | RICOH IMAGING
By the end, I was feeling a strong urge to buy an FA31 by the end of the talk. Perhaps I can justify it to myself one day.
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Forum: Pentax SLR Lens Discussion
10-05-2019, 10:47 AM
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I recently purchased a Takumar 35mm f2.3. So far it's lived up to its reputation - beautiful colors, fantastic rendering wide open, and very sharp closed down.
As with all of these early Tak's, they don't do well shooting into the sun since they lack the SMC coatings. This lens is particularly sensitive to flairing because of the rather exposed first element.
There is a lens hood for it, but it is very rare to find one. It screws onto the outside of the lens barrel. You can't use the filter threads to put on a substitute hood because it will cause vignetting.
My solution was to design a new hood and 3D print it. There is a split collar that attaches to the barrel with a small screw. The collar makes it difficult to get that lovely lens cap off, so I put some cut-outs in the sides of the collar. The hood is a bayonet mount that is reversible. Now that precious outer element is protected by the hood, and there are less issues with flare. The only downside is that the lens doesn't fit in its original case with the collar attached. Perhaps I'll design a quick-release collar to deal with that issue. Below are some photos of it on my K-70, and mounted on its contemporary, the Asahi Pentax S. The printed plastic was a shiny black so I've painted it to be more of a matte color.
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Forum: Film SLRs and Compact Film Cameras
03-22-2019, 06:26 AM
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Hey everyone, I thought there may be some interest in sharing this here.
After getting inspired by the Pentax KP custom with a wooden grip that was shown off recently, and then watching some viral videos about making things from colored pencils, I decided to give it a go but with a camera grip.
I realize not everyone is gonna jive with the style, but I think it looks pretty cool.
Here are some pics of a the process, and there's a video at the end with more details.
What do you think?
 colored pencil camera grip project by ThatA480Guy, on Flickr
 colored pencil camera grip project by ThatA480Guy, on Flickr
 colored pencil camera grip project by ThatA480Guy, on Flickr
 colored pencil camera grip project by ThatA480Guy, on Flickr
 colored pencil camera grip project by ThatA480Guy, on Flickr
You Tube
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src="https://www.youtube.com/embed/a25_GfwZdjw?controls=1" allowfullscreen>
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Forum: General Photography
12-05-2018, 05:49 PM
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I'll start this off with a like-new K/R mount Ricoh XR-X 3PF camera body.
It's a sophisticated electronic film SLR, probably Ricoh's final film SLR model.
Manual here: https://www.butkus.org/chinon/ricoh/xr-x3pf/xr-x3pf.pdf
I haven't processed any negatives and I don't have a Ricoh "P" lens to test it with
however shutter, transport, exposure system etc. all appear to be fully working.
Free, shipped free within USA only.
Send PM if interested.
Feel free to join in and post in this thread offering up your unneeded/unwanted film gear.
Happy holidays!
Chris
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Forum: Pentax Price Watch
11-24-2018, 02:24 AM
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So...... A wonderful thing happened here. A very generous PentaxForum's member contacted me, and said he had an offer I couldn't refuse. George is in NY , the opposite side of the planet from me, He said, he used to have that lens, but no longer does, BUT, he had the palm-rest still, and he would send it to me. And he did, no reward or payment, he posted it to me here in Australia.
Truly a wonderful gesture, that has made me want to say. Thank you George.
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Forum: Sold Items
08-12-2018, 04:36 PM
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Thank you :)
---------- Post added 08-13-18 at 12:37 AM ----------
Replied !
---------- Post added 08-13-18 at 12:37 AM ----------
Replied !
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