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2023-08-17

Books of my childhood

As a child, I really loved to read. But fiction was in short supply, and good books at the local library were only available in the reading room. So I read whatever I could find.

These two books really amazed me and had a big impact on me.



"Алгоритмический язык Фортран" ("Fortran Algorithmic Language") и "Программирование для всех" ("Programming for Everyone").



Both books were about the Fortran programming language.



Not everything was clear, but it was very interesting. It was all theory, I didn't have any access to computers at that time.

It's funny that I never programmed in Fortran after that, although I used many different programming languages.



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Posted by malykh в 00:02 0 comments

2023-08-16

Risespray 11/2.8 Fisheye: repair and first impressions

So I decided to repair the new Risespray 11/2.8 lens that had a lot of play in the focusing mechanism.

The construction of the lens is simple and easy to disassemble. The main problem was the loose screws (marked in the picture):



I completely disassembled, cleaned and reassembled the focusing mechanism.

The aperture ring with the Molykote 33 Light grease became very easy to turn, which made using the lens very uncomfortable (because the ring is clickless). So instead I used the Ford XG-3-A like a damping grease. This made the ring even stiffer than the original.

There is still some play in the focusing mechanism (by design), although it is quite small, but it is noticeable at such a short focal length. Therefore, it is impossible to adjust the hard stop of the focus ring to infinity precisely (at f/2.8). If a part of the lens moves due to the play, the focus will go before or beyond infinity. Anyway, this is my high expectations.

But the optics are good, I liked it. It is definitely better than the Зенитар (Zenitar) 16/2.8 Fisheye.





I will shoot some more, it is interesting to compare different fisheye projections of the Risespray and the Zenitar, and then I will sell the Zenitar (by the way, I bought it in 2006).



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Posted by malykh в 00:05 0 comments

2023-08-15

M42x1-M39x1 adapter (4.5mm)

This is a rare M42x1-M39x1 adapter:



It is for a M42x1 lens and for a M39x1 camera:



Reverse (M39x1-M42x1) adapters are known, they look like a ring, whereas this adapter looks like a step-up adapter for photographic filters. But it is not, because filters of this size usually have the 0.75mm thread pitch (or even less). This adapter has the 1mm thread pitch (for lenses, not for filters).

Warning: Some sellers misrepresent this adapter as a filter step-up adapter, so clarify the information.

It is possible to mount a M42x1 lens:



And it can be mounted on a M39x1 camera (in this case the M39x1-Sony FE adapter):



But you have to take into account that the adapter is thin (about 4.5mm). It does not correspond to the difference in flange focal distances of M42x1/45.5mm and M39x1/28.8mm (rangefinder), i.e. 45.5-28.8=16.7mm. Therefore, focusing will be far beyond infinity. For real use you have to use extension tubes (16.7-4.5=~12.2mm) or the like.

And of course there is no rangefinder coupling if you want to use the adapter with a M39x1/28.8 rangefinder camera.

Also note that not all lenses can be screwed in completely because the M42x1 thread length of the adapter is quite short (4mm). For example, the Takumar 105/2.8 (Pre-Set II):



You can see the gap between the lens flange and the adapter. You can use it this way, but keep in mind that it increases the flange focal distance of the lens.


Such an adapter (like the M42x1-Sony FE/E thin adapter) is usually used for experiments with non-standard [adapted] lenses.

Posted by malykh в 00:03 0 comments

2023-08-14

Risespray 11/2.8 Fisheye (for full-frame mirrorless cameras)

The very little known the Risespray 11mm f/2.8 (11 F2.8) Fisheye lens.



It is a fisheye lens made in China. It is available for full-frame mirrorless cameras with Sony FE/Canon RF/Nikon Z mounts.

I have the Sony FE version, it's a manual focus non-electronic lens. I bought it as the cheapest fisheye for the [full-frame] Sony FE mount, it cost me about $140. The TTArtisan 11/2.8, the 7Artisans 10/2.8, the Samyang/Rokinon 12/2.8 are more expensive.

This lens has a clickless aperture change from f/2.8 to f/16:



I don't like this kind of control, it's very uncomfortable for photography. The aperture ring is a bit stiff, but it's easy to accidentally move the setting off, and it's almost impossible to blindly set the desired aperture value.

The best option for non-electronic lenses is an aperture preset mechanism like on older lenses. Unfortunately, I have not seen this on modern lenses.

The aperture consists of 10 blades:



Optical design: 11 elements in 7 groups



An unusual push-on metal cap:



I think the cap does a pretty good job of protecting the convex front optical element. If the cap doesn't come off by itself, of course.



The lens isn't that small. A little bigger than the Зенитар (Zenitar) 16/2.8 Fisheye with the Pentax K-Sony FE/E adapter.



What is the origin of the lens, since Risespray is not a manufacturer? This lens is very similar to the TTArtisan 11mm f/2.8 Fisheye:

(TTArtisan 11/2.8 Fisheye, mirrorless versions)

The optical design is also very similar (to the mirrorless version of the TTArtisan):

(TTArtisan 11/2.8 Fisheye)

Both lenses (the Risespray and the mirrorless TTArtisan) have the same distance scale (m): 0.17-0.2-0.25-0.3-0.5-1-∞.

The mirrorless TTArtisan has 7 aperture blades, but the later SLR version has 10 blades.

(TTArtisan 11/2.8 Fisheye)

Unfortunately, the Risespray lens has a clickless aperture ring like the mirrorless TTArtisan, while the SLR TTArtisan has a click ring.

I think the Risespray 11/2.8 Fisheye is a clone of the TTArtisan 11/2.8 Fisheye lens (I don't know the original manufacturer), but it is cheaper since the lens has just started being sold under the Risespray brand.


My copy of the Risespray 11/2.8 Fisheye was new in a sealed box. When I started using it, I was confused by how far beyond infinity it focused. Then I noticed a strange slipping of the focus ring. I even tightened the screws of this ring (hex 0.9mm). But that didn't help.

It turns out that there is massive play in the focus mechanism:



This is quite unpleasant, there seems to be no quality control at all here. By the way, the seller's reviews also contain complaints about the quality of the lens.

My hope is that I can get the lens repaired and have a chance to use it.

Posted by malykh в 00:01 0 comments

2023-08-13

Samsung NX300: dead pixels on the LCD AMOLED screen

The story of the Samsung NX300 LCD AMOLED screen continues. In addition to the decrease in brightness and visible "ghosts", there are now "smudges" and even dead (always black) pixels:



The screen is getting worse. It is quite possible that sooner or later it will stop working altogether.

I still don't know the reason for this screen degradation.

p.s. I no longer use this NX300. I have the NX2000 instead.



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Posted by malykh в 00:01 0 comments

2023-08-12

Zenitar 16/2.8 Fisheye and distortion correction

I have already shown an example of correcting Зенитар (Zenitar) 16/2.8 Fisheye distortion for video (using Gyroflow). For photos, I am more used to using panorama software (Hugin now).

But if we consider Zenitar images as "Normal (rectilinear)", then the a, b, c parameters are not enough to correct the distortion completely. If you change the lens type to "Full frame fisheye", you still need to optimize a, b, c for good enough distortion correction. But it is possible.

Examples of distortion correction: before and after. I left partially visible edges of the result to illustrate the angle of view.



















And lens distortion should not be confused with perspective when the camera is tilted (for example, "falling buildings" in the corrected images).

Posted by malykh в 00:13 0 comments

2023-08-11

Вега-22УЦ (Vega-22UTs) 103/5.6 user manual (1979)

The Вега-22УЦ (Vega-22UTs) lens is designed for a photographic enlarger, but I used it as a macro lens with bellows (M42x1). Only the user manual 0640.00.00.000 ПС (1979) was left.






Then I switched to the Вега-5У (Vega-5U) 105/4 (also M42x1).

Now I have no more enlarging lenses, instead I use Pentax M 100/4 Macro (without bellows).



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Posted by malykh в 00:00 0 comments

2023-08-10

Mosler Photoguard 35/2.8: Samples [1] - FF + close focus (helicoid) adapter

The Mosler Photoguard (Tokina) 35/2.8 lens has a long minimum focusing distance. So it made sense to test it with a combination of adapters: the Pentax K-Leica M adapter and the Leica M-Sony FE close focus (helicoid) adapter.

(at the shortest focusing distance)

The lens without any extension tubes: minimum focusing distance 570-575mm, maximum magnification 1:13.2, x0.076. Too bad.

The lens with the close focus adapter: minimum focusing distance 270-275mm, maximum magnification 1:4.9, x0.20.  That's nice.

Using the close focus adapter in real life is quite easy. Much more practical than using an extension tube or bellows.

Examples of close-up shots (the Sony a7c, 24MP FF) at f/2.8:










There are interesting results, but it is still better to use this lens for landscapes, I think.

Posted by malykh в 00:00 0 comments

2023-08-09

242x175x190 (mm) battery and Suzuki SX4 Classic (Magyar/Hungarian)

A standard 278x175x175 (mm) battery of the Suzuki SX4 Classic (Magyar/Hungarian) can be replaced with a larger 278x175x190 (mm) battery. There is enough space and cable length.

It is also possible to install a 242x175x190 (mm) battery, but it has to be moved towards the negative cable, which is otherwise not long enough.



In this position the battery is well secured by the stock carrier.

By the way, a battery of this size but with a different terminal layout is installed on my Jeep Cherokee KJ (V6 3.7).

Posted by malykh в 00:00 0 comments

2023-08-08

Noname Pentax K-Leica M adapter

An adapter for Pentax K mount lenses.



To be installed on Leica M mount cameras.



There is even a blank template for 6-bit code.



I don't have a Leica M mount camera. I use this adapter together with a second adapter: Leica M-Sony FE/E close focus (helicoid) adapter.

It works fine, but there is a rather noticeable focusing beyond infinity. This is mostly the fault of the Pentax K-Leica M adapter (too thin).

There is also some play, I've already written about that.

But it allows to focus a Pentax K lens to infinity, and then to reduce the focusing distance as when using an almost 5mm extension tube. And this is not so small for short focal lengths (up to 50 mm).

Posted by malykh в 00:00 0 comments
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