ISCO Iscovitar 50/2.8: Samples [1] - FF - f/2.8

Photos taken with the Sony a7c (FF, 24MP) and the ISCO Iscovitar 50/2.8 at f/2.8.

Because the lens focuses by rotating and moving only the front optical element, it doesn't produce a "classic" triplet image with "soap bubbles" and so on. And some soft focus effect is visible.

See also related notes:

• ISCO Iscovitar 50/2.8 (M42x1/45.5): Triplet with simple focusing mechanism (2024-05-21)

Image albums:

• ISCO-Göttingen Iscovitar 50/2.8

Panasonic Lumix S9: Full-frame camera + 26/8 lens

The Lumix S9 is Panasonic's all-new full-frame mirrorless camera.

It is quite small (for the digital full-frame world), but there is no EVF and no mechanical shutter.

But there is IBIS. And a fully articulating screen.

The new Panasonic S 26/8 lens is strange for today.

It has manual focus and no aperture control. But I think it is a lens for fun. And its focal length is obviously a "tribute" to a [main] camera of mobile phones.

Is the f/8 too slow? For example, the modern mid-range Google Pixel 8a has a main camera with an equivalent focal length of 26mm (yes!) and f/1.89. Its sensor size is 1/1.73, 4.7x crop factor. So the equivalent aperture is about f/8.9 (1.89 * 4.7).

Or, f/8 of FF is equivalent to f/4 of M4/3.

By the way, I would buy a similar lens for the Sony FE mount for a reasonable price. I tried the Brightin Star 23/5.6, but it is a junk lens with poor build quality. I also had the Holga [NX] 29/8, it was a very fun lens almost for free. But it is about f/20 instead of (stated) f/8 because of the two apertures. And the Holga is for APS-C, so it is a normal focal length (not a wide angle) lens.

See also related notes:

• Holga HL(W)-SSN 29/8: On the full-frame camera (2023-02-19)
• Brightin Star 23/5.6: странный китайский объектив для Sony FE/E (2022-03-19)
• Holga HL(W)-SSN 29/8: объектив-спецэффект за $16 (2014-05-04)

Image albums:

• Photo

Suzuki N32 (Grand Vitara JB632W) ECM pinout

The ECM pinout for the the Suzuki N32A (V6 3.2 liter) engine. I found it in a service manual for the Suzuki Grand Vitara JB632W. I hope to use this pinout to start the 33910-79K00 control module.

Version 1:

Version 2:

See also related notes:

• Old service manual and VirtualBox (again) (2024-05-31)

Image albums:

• Suzuki

Holga HL(W)-SSN 29/8: Samples [1] - APS-C

Photos taken with the Samsung NX10 (1.5x crop factor, 14.6MP) and the Holga HL(W)-SSN 29/8 (there is no aperture control).

See also related notes:

• Holga HL(W)-SSN 29/8: объектив-спецэффект за $16 (2014-05-04)

Image albums:

• Holga

ISCO Iscovitar 50/2.8 (M42x1/45.5): Triplet with simple focusing mechanism

I already have two triplets: the Anastigmat Victar 50/2.9 (M40x1) and the Staeble-Werk Choro R 35/4.5 (M39x1/44). I wanted a triplet for the M42x1 mount. I thought about a later Domiplan 50/2.8 (one of the cheapest options), but by chance I found an alternative.

It is an Isco-Göttingen Iscovitar 1:2.8/50, also known as Isco-Göttingen Edixa-Iscotar.

Yes, it is a triplet (i.e. it contains 3 elements in 3 groups). Something like a Cooke triplet:

This is a cheap (for its time) lens with plastic body parts, it feels cheaply built. It reminds me of the Revue 24/4 lens.

The aperture has only 5 blades.

As you can see, my copy obviously needed service or even repair. But so far I only use it at f/2.8. For more stopped down apertures I have other lenses.

There is an "automatic" aperture pin.

But you can switch from the A to M mode to control the aperture directly.

The aperture ring has click stops at f/2.8, f/4, f/5.6, f/8, f/11, f/16.

There is a screw thread near the aperture mechanism.

 

As far as I know, this is for a threaded cable release.

(source unknown)

Maybe for macro photography with bellows (with double cable release)?

The filter thread is 49mm. The front part of the lens (with the filter thread) rotates during focusing. And this simple focusing mechanism is the most interesting part of the lens.

When I started using the lens, its image production at close focus reminded me of the Riconar/Rikenon 55/2.2 lens. Very similar soft focus effect. And the reason is the same! The simple focusing mechanism moves the front optical element only.

And again, the minimum focusing distance is about 0.8m (too far for a 50mm SLR lens). At the shortest distances, a soft focus effect would be too much. And of course, manual focusing is quite difficult.

See also related notes:

• NONS SL42 (II): MC7 x2 teleconverter (2025-09-07)
• NONS SL42 (II): NFE, Pentax K lenses (2025-08-25)
• My triplet lenses (2024-08) (2024-08-27)
• ISCO Iscovitar 50/2.8: Samples [1] - FF - f/2.8 (2024-05-25)

Image albums:

• ISCO-Göttingen Iscovitar 50/2.8
• Staeble-Werk Choro R 35/4.5
• Staeble-Kata E 45/2.8
• Victar 50/2.9

Thread mount SLR lenses for M39x1 rangefinder cameras

I have two adapters for thread mount SLR lenses. Both are serial products, both are for mounting on M39x1/28.8 cameras.

First (on the right) is the rare adapter for the popular M42x1/45.5 SLR mount. Its length is 16.7mm.

Second (on the left) is an adapter for the much less popular M39x1/45.2 SLR mount (lenses made in the USSR for early Zenit cameras). Its length is 16.4mm.

Theoretically, there could be an adapter for the M40x1/44 SLR lens (for the old Praktiflex cameras) with a length of 15.2mm. But I have never seen a serial product (without 3D printing etc.). I use a combination of different adapters to mount these lenses on the M39x1/28.8.

See also related notes:

• M42x1-M39x1 adapter (16.7mm) (2024-03-20)
• Praktiflex M40x1 lenses on modern cameras (2023-08-25)
• M39x1/45.2 (SLR) lens list (2023-08-05)
• Использование объективов M39x1 на цифровых камерах (2022-05-18)

Image albums:

• Lens accessories

Five Star 500/8: Samples [1] - FF - f/8

Photos taken with the Sony a7c (FF, 24MP) and the Five Star 500/8 at f/8.

See also related notes:

• Таир-3C и Five Star 500/8 (2022-05-26)

Image albums:

• Five Star 500/8

Takumar 105/2.8 series: 4/4 vs 5/4 designs [1]

There are two optical designs in the Takumar 105/2.8 series. The older one is 4 elements in 4 groups (Takumer Pre-set I, Auto-Takumar). The later one is 4 elements in 4 groups (Takumar Pre-set II, Super-Takumar, S-M-C Takumar, and Pentax K 105/2.8).

I have both types: the Auto-Takumar 105/2.8 (4/4 design) and the Takumar Pre-Set II (5/4 design).

I wanted to compare them to see if the older 4/4 design is better, as is sometimes said?

I expected to find a small difference between images taken with the lenses. But the difference is noticeable when you compare images side by side.

The 4/4 design lens has a slightly wider angle of view than the 5/4 design lens. And the 4/4 design lens has a barrel distortion, while the 5/4 design lens has a pincushion distortion.

1. 4/4 design:

5/4 design:

2. 4/4 design:

5/4 design:

3. 4/4 design:

5/4 design:

I usually prefer a wider angle for the same focal length. But the pincushion distortion of the 5/4 design may be better for real-world photography.

Also, when using a lens with an adapter, the preset aperture control is more convenient than the direct aperture control of Auto-Takumar. Especially when shooting movies.

See also related notes:

• Takumar 105/2.8 series: 4/4 vs 5/4 designs [2] (2024-07-24)

Image albums:

• Auto-Takumar 105/2.8
• Takumar 105/2.8 (II)

Defective tripod plate (Arca Swiss style mount)

A Chinese tripod plate with an Arca Swiss style mount. When I tried to mount the plate, I found out that it is defective:

As you can see, the angle of the bevels is not correct (wrong profile).

For comparison, another Arca Swiss style plate:

It is ok. So the problem is with the defective tripod plate, the clamps have the correct profile.

See also related notes:

• Штативная площадка с держателем (подобно "Arca Swiss") (2022-08-25)
• Штативная площадка (почти подошла) (2016-06-25)

Image albums:

• Tripod