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2023-07-29

Pentacon 30/3.5: My experience [1/5]

I liked the Pentacon 30/3.5 (M42x1) lens, although it has some weaknesses. I use this lens on the Sony a7c (24MP, FF).

The resolution in the center is good even at f/3.5 at infinity.



The edges, and especially the corners, don't have very good resolution even with the aperture closed.

Here and follow the f/9.5 aperture:



Of course, the simple optical design (5 elements in 5 groups) of a retrofocus wide-angle lens is no miracle. The Pentacon 30/3.5 also has a design flaw: decentering is often present. My copy is good, but it too has some decentering.




Overall, I like the image and the color rendition (for an old lens, especially compared to Soviet lenses).




10 blades make 10 sunstar rays.




The point of this lens is close-up photography (down to 30-35cm) at f/3.5. I will demonstrate this further. See part 2, part 3, part 4, part 5.

2023-07-28

120cm sand ladders for Jimny

I bought aluminum sand ladders (aka sand tracks, aka recovery tracks/boards) for my Suzuki Jimny in 2010.



Two pieces, made by Автощит (AutoShield), part number 9112, length 120 cm.



Not very long, but uncomfortable to carry in the Jimny, so I carried them on the roof.

I didn't use them much on trips, but they helped a lot at competitions where you're not allowed to use a winch. Basic use: lifting the car (with the Hi-Lift jack), putting ladders under the wheels.

But I stopped competing a long time ago, and ladders take up a lot of storage space. That's why I sold them this year.

2023-07-27

Cannondale Cujo 1 (2018): 27.5x3.0" and 27.5x2.8" tires simultaneously

After the chain came off my bike, the rear rim was damaged. Now the wheel is not centered (out of dish), the distance to the frame on one side of the wheel is too small. The 27.5x3.0" tire sometimes rubs against the frame.

I can't change the wheel/rim now (and I'd like to put 29" wheels), so I made a compromise solution to save the frame. I left the 27.5x3.0" tire on the front, and went back to the 27.5x2.8" tire on the rear, which is a little narrower, and that's enough.

The difference in diameter is almost imperceptible.



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2023-07-26

Angarsk: 10 photo card set from 1969 (and 2023)

A rare set of Angarsk photos from 1969: 10 photos and 2 covers. This set is related to the set of panoramic photos from the same time period.


And also my photos of the same places from the ground (July 2023).

Disclaimer: My photographs are nothing more than a documentation of reality.


Cover-1: Ангарск (Angarsk)




Cover-2.




1. Улица Горького (Gorky Street)



The photo was taken at about the same time as the panoramic version.




2. Дом пионеров (A Young Pioneer House)




3. Железнодорожный вокзал (The railway station)



The original monument was lost in the 2000s. A modern made replica was installed in 2019.



4.Стадион "Ангара" (Stadium "Angara")




5. Площадь Ленина (Lenin Square)




6. Ул. Ленина (Lenin Street)



The photo was taken simultaneously with the panorama, or this is a cropped version of the panorama.





7. Улица Карла Маркса (Karl Marx Street)




8. Ул. Чайковского (Tchaikovsky Street)




9. Проспект Ворошилова (Voroshilov Prospect)



The photo was taken at about the same time as the panoramic version.




10. Дворец культуры "Современник" (Place of Culture "Sovremennik"/"Contemporary")




2023-07-25

Toopre TL-311: Tool for Shimano PD-M530 pedals

The cheap Toopre TL-311 tool (wrench) for disassembling Shimano PD-M530 pedals, alternative to Shimano TL-PD40:



Looks like an adapter that allows a regular 24mm wrench to unscrew the pedal nut:



Tested it on my pedals, it all fit:



With the help of this tool I was able to disassemble the pedals, clean them and grease them.



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2023-07-24

Anastigmat Victar 50/2.9 (M40x1): Uncoated triplet from 1940s

My oldest and most unusual lens.



This German lens was made (by Optisches Werk Ernst Ludwig) for Exakta and Praktiflex SLRs as a low-cost standard lens. It had different names: 
  • Victar 1:2,9 F=5cm Ludwig-Dresden
  • Anastigmat Victar 1:2,9 F=5cm
  • Victar 1:2,9 F=5cm
  • Praktiflex Anastigmat 1:2,9 F=5cm (OEM for Praktiflex)
  • Practicar 1:2,9 f=50mm (Export)

I have the Anastigmat Victar 1:2,9 F=5cm version for Praktiflex with the M40x1 mount from the 1940s. And there is no serial number at all.

There is a claim that the lens has 4 elements in 3 groups, but I don't think so. The 1939 price catalog lists 3 elements for the Praktiflex Anastigmat 50/2.9. The 50/2.9 successors of this lens, called Meritar and Peronar, also have only 3 elements. However, the f/2.9 is quite fast for the a triplet.

(the optical design is similar to this one)

This lens also had no optical coating, which makes it something special today.

The lens is tiny. It (on the right) is smaller than the Индустар-50 (Industar-50) 50/3.5 (on the left) and the Индустар 50-2 (Industar 50-2) 50/3.5 (in the middle):



There is a cutout for mirror movement.




The aperture has 13 blades. Almost an even circle, but you have to consider the age.



Note that the lenses are almost colorless (no coating).

The focusing mechanism is quite good. When focusing, the front part does not rotate, so you can change the aperture without fear of losing focus. The mentioned Industars are much worse in this aspect.

The M40x1 (that's right, not M39x1 or M42x1) mount with the 44mm flange focal length (smaller than the 45.5mm of M42x1) for the first Praktiflex SLRs is very rare, so it's not so easy to adapt it to modern cameras, although it's possible.

Of course, this lens is not suitable for general use now, but its own nature is interesting.

I've wanted a triplet lens for a long time. I already have the Riconar 55/2.2, but it's not a triplet. The Victar is now the first triplet I've ever owned. The copy is not perfect, but it is playable.



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2023-07-23

Near Lake Ilchir (August 2008)

Aircraft сontrails over one of the lakes near Lake Ilchir, August 2008.



Pentax K10D (10MP, 1.5x crop factor) + DA 18-55/3.5-5.6 AL (i.e. first version) @ 18mm (28mm equiv.)



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2023-07-22

Uvex Pheos One (9192370)

The Uvex i-3 safety glasses (spectacles) are good, but they do get scratched up a lot. So I replaced them with Uvex Pheos One (9192370).



Simpler but cheaper.

(a picture from somewhere on the internet)




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2023-07-21

Molykote 33 Light: application for lenses

I purchased Molykote 33 Light grease primarily for lens applications.

The 33 Light reminds me of GM Special Lubricant High Temperature grease, they have a similar consistency (NLGI 1). However, there are important differences:

1. GM provides better lubrication. Apparently because of the PTFE.

2. Molykote does not separate or bleed, unlike GM.

3. Molykote is almost odorless.

This is why I switched to using Molykote 33 Light. The first application was on the Pentacon 30/3.5 lens. It had never been disassembled, the original grease had dried up, so the focusing ring was too stiff.



The focusing mechanism of this lens is like the "inverted" mechanism of the Индустар-61Л/З (Industar-61L/Z) on which I tested the greases.

First impressions after using Molykote 33 Light are good. But I wish there was a PTFE additive for even lighter movement.

2023-07-20

SZ Viewer: "lacks permission android.permission.BLUETOOTH"

The updated version of SZ Viewer may display an error message: UID ... / PID ... lacks permission android.permission.BLUETOOTH 

This is a problem with some Chinese Android 12+ devices: mainly Xiaomi, but other brands are also affected (Oppo, etc.). It is caused by an incorrect implementation of the Bluetooth stack (permissions).

There is a workaround, but I don't plan to try it right now. SZ Viewer users can either manually roll back to an older version, or hope that the manufacturers will fix the Bluetooth bug of their devices.



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2023-07-19

A traveling cat (1980s)

A traveling cat.



This photo was taken in the 1980s. The tent in the background with its blurred logo looks like the old Polish Rymarzy Krakow tent.



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2023-07-18

My Mosler Photoguard 35/2.8 and infinity focus

My Mosler Photoguard (Tokina OEM) 35/2.8 focuses beyond infinity, which is inconvenient. I've tried different T[2]-mount adapters, but there's no difference. At the same time, I don't want to disassemble the lens to adjust it now.

So I chose the simplest way. I put some pieces of thin foil between the T[2]-mount adapter and the lens and corrected (returned back) the orientation of the lens with the screws of the adapter.



It looks not very good, but focusing became almost at infinity.

But in the future, of course, it would be nice to adjust the lens.

2023-07-17

34960-81A00 vs 34960-81A20: VSS for my Jimny

One Jimny owner offered to swap my 34960-81A00 vehicle speed sensor (VSS) for his 34960-81A20. Since I have several 34960-81A00 sensors, I of course agreed.

On the left is the 34960-81A00 (for 4.09 + 205/70R15 or 4.3 + 175/80R16), on the right is the 34960-81A20 (for 5.375 + 175/80R16).



Using the diagnostic software (speed value for ECM) and GPS, I made a comparison.

Stock: final drive ratio 4.09 + 205/70R15 (about 26") tires, now: 5.375 + 30".

With the 34960-81A00 (stock) VSS:

("Скорость" means "Speed" in km/h, I forgot to change the language)

VSS shows 60 km/h at 51 km/h. Quite an overestimate.


With the 34960-81A20 VSS:

("Скорость" means "Speed" in km/h, I forgot to change the language)

VSS shows 48 km/h at 50 km/h.

This way the readings are closer to the real speed. The only bad thing is that the indicated speed is lower than the real one. But this is on the diagnostic, whereas the speedometer readings are the same as the real speed.

Of course, with bigger wheels (32"/34") the indicated speed will be lower, but now I use only 30" for long distances.

So I left the 34960-81A20 installed on my Jimny. And I need to correct the speed coefficient for the RIF-500 trip computer.

By the way, the automatic transmission control module of my Jimny doesn't use VSS at all. Instead, it receives a fake signal from an NE555 pulse generator to enable 4th gear and lock up the torque converter even when the low range of the transfer case is engaged.

2023-07-15

Angarsk, Storm (2004, July 16)

Angarsk, storm (sometimes referred to as a hurricane), 2004, July 16.



Pentax Optio 450 (4MP, 1/1.8").



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