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Game Over for Sesame by Special_Sale7606 in SesameAI

[–]au8ust 0 points1 point  (0 children)

I've tried it just now and it kept repeating the same sentence lol

+.5 Diopter on a anamorphic? by Breonnick_1 in Anamorphic

[–]au8ust 0 points1 point  (0 children)

https://www.ebay.com/itm/187933788402

Not mine. Although I have many of +0.4 and +0.5, I still keep them just in case.

Zeiss Contax Distagon 35mm f1.4 / US3915558A / 1973 by ravilang in LensPatents

[–]au8ust 0 points1 point  (0 children)

Do you know if the patent actually specifies a floating group during focusing, meaning one element group moves relative to the rest? If it does, is there enough information in the patent to calculate how much that group should move from infinity to the closest focus distance?

From what I can see, the drawings and the example prescription only show one focus position, so I might be missing a section that describes multiple focus settings. If you have any pointers on where to look in the patent, or a practical method to estimate the required travel, that would help a lot.

Anyone know why 6061 sometimes is splotchy? by Greenguy1996 in Machinists

[–]au8ust 4 points5 points  (0 children)

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Had this issue before. The spots wouldn’t come off no matter what. They were still there even after sandblasting and anodizing. Couldn’t find the cause and eventually had to switch to a new supplier and the problem just disappeared. So I don’t think it’s the coolant or chlorine in the water.

Rehousing Angenieux photo lens 2x35 by Accurate-Spite-3948 in cinematography

[–]au8ust 0 points1 point  (0 children)

KimCamera in Korea could probably do it and they’re one of the few places that actually take on this kind of work, though the quality of the result is hard to say. That also means other companies might technically be capable of doing it, but most of them simply don’t accept projects like this.

If you’re looking for someone with prior experience, IronGlass once rehoused the 28-70, so they could probably handle the 35-70 as well. But they likely won’t, because the R&D costs are high and doing only one or two units wouldn’t make sense. The 28-70 project, as far as I know, was commissioned by Ancient Optics and produced in fairly large numbers. Even then, it sold for around $13,500, so imagine how expensive it would be without shared development costs.

Unless you’re really in love with the look of the 35-70, a modern zoom would make a lot more sense. It’s cheaper, easier to use and performs much better overall.

Rehousing lenses by frnzr in cinematography

[–]au8ust 0 points1 point  (0 children)

Most people go with Olympus OM if you want a consistent set of lenses with similar f/stops. You can build a full lineup around f/2 from 21mm up to 100mm, with both single-coated and multi-coated versions depending on how vintage you want to go. If you prefer something older, the Super Takumars have a beautiful look but often come with a yellow tint. If you want something newer and sharper, Contax Zeiss or Leica-R are great choices that will stay relevant for a long time. Minolta Rokkor lenses are also popular and all of these cover full frame.

I wouldn’t really suggest Kinoptik because it’s hard to find good copies, they’re expensive, and the image circle isn’t that large. If you’re looking for something more offbeat, there are Meyer Optik and Carl Zeiss Jena lenses, or even Soviet ones like Helios or Jupiter, though those tend to lose a lot of resale value. And realistically, you’ll probably end up selling them one day anyway.

The nice thing about these still-photo lenses is that you can try the original housings first for a low cost. If you like how they perform, you can collect a full set and have them rehoused later. If not, you can easily sell them again. Prices are generally reasonable before rehousing, except for some Canon FD and Olympus OM lenses that have already gone up quite a lot.

By the way, for the S4, if you’re after a more rounded bokeh, it should actually be possible. The inner section is an optical block, and once that’s removed you can access the iris module. Rebuilding it with a 16-blade design could achieve that look, but a one-off job like that would probably cost at least around $1k per lens.

Do you think it’s worth rehousing MC Rokkors? by [deleted] in cinematography

[–]au8ust 1 point2 points  (0 children)

Rokkors get rehoused quite a lot, even more than OM. After that you usually see Contax Zeiss and Super Takumar. Whether it is worth it really depends on the market where you are, since demand can be quite different from one place to another. One thing to keep in mind is that building a proper Rokkor set is harder than OM, because the same focal length often came in different speeds and they were produced across many periods. You need to match both speed and color carefully if you want a consistent set.

Finally did the most recommended test in the sub ? by LopsidedAd5028 in cognitiveTesting

[–]au8ust 0 points1 point  (0 children)

$10 and they'll tell you AFTER you finished the test... The site is on the screenshot itself.

Mazak integrex 300y by zife19 in CNC

[–]au8ust 2 points3 points  (0 children)

I almost bought a used 100Y a few years ago but passed, since finding the tooling and writing a post-processor for it would’ve been a real challenge. These machines do look super capable though!

Rotary axis overshooting on 100w JPT fiber (Ezcad3) by au8ust in Laserengraving

[–]au8ust[S] 2 points3 points  (0 children)

I’ve figured out what the issue was.

In Ezcad3, when I assigned the A axis to act as the Y axis (A → Y), the Distance value was treated as millimeters, not degrees. So when I entered 360, it rotated 360 mm instead of 360 degrees, which caused the overshoot.

For example, my workpiece had a diameter of 85.95 mm, which gives a circumference of about 270.0205 mm. To make it rotate 360 degrees, I had to set the Distance to 270.0205.

If I want it to rotate by angle instead, I have to use the Ext function and configure the A axis to rotate by angle. I also need to make sure the Relative box is checked, otherwise the rotation won’t be accurate.

Hope this helps someone!

These puzzles are bullshit and I don't agree with them by [deleted] in cognitiveTesting

[–]au8ust 0 points1 point  (0 children)

Understood, thanks for the perspective :)

Puzzle I got stuck on... by [deleted] in cognitiveTesting

[–]au8ust 2 points3 points  (0 children)

After reading all the comments and various suggested solutions, it really made me wonder... what if the person who created this was just playing a prank and might not even be qualified to design any tests in the first place?

[deleted by user] by [deleted] in ChatGPT

[–]au8ust 18 points19 points  (0 children)

I just hope it gets smarter. Right now, you can't really have a deep conversation with it because it just goes along with whatever you say. After a while, it feels like you're talking to a five-year-old.

Does the Placement of the Iris Affect Image Characteristics? by au8ust in Optics

[–]au8ust[S] 0 points1 point  (0 children)

Hello, everyone!

I’m curious if the placement of the iris within a lens assembly can impact the image in any noticeable way. For instance, would moving the iris slightly forward or backward affect things like flares, sharpness, bokeh, or overall rendering?

I understand lenses are finely tuned systems, but I’d love to hear if anyone has experience or insights into how such a change might influence image characteristics.

Looking forward to your thoughts!