The "Projector Lens" Club ...

Pedro Alanis · 02-26-2022, 11:57 AM

Originally posted by fiveseven

Some of my projector lenses.....It's pretty awesome the resolution from them vs regular camera lenses.
About your Kp35 1.8/100, the aluminum tube that supports the lens and has the m42 mount, what type of lens or projector does it originally belong to?

About your Kp35 1.8/100, the aluminum tube that supports the lens and has the m42 mount, what type of lens or projector does it originally belong to?

169 · 03-02-2022, 05:24 PM

These aren't very common, but Schneider fitted their stock 90/2.4 with a variable iris (Schneider Catalogue 62094.979.399 / Delta SKU #1812 - see here for details) that ran to f8. Wide open, it's typical of most good, fast 90s, but the ability to stop it down without a hacked aperture makes it friendly for those who want the projector lens look without projector lens inconvenience. Schneider's iris is excellent, too - but the clickless ring is stiff on both my samples.

169 · 03-02-2022, 05:26 PM

For giggles, here's the same leaf shot made with the mighty Cabin 100/3.2 (Delta SKU #0395): my favourite projector lens for people who don't want to adapt projector lenses. Those beautiful people at Cabin fitted it with an M39 thread.

lehoward · 07-14-2022, 06:16 AM

Dear sirs,I would like to share some photos taken with Isco Projar 1:2.8/85mm. Photos are JPEG, no PP.

Attached Images

View Picture EXIF

View Picture EXIF

junkbench · 07-26-2022, 02:08 AM

Has anyone adapted a bell & howell Trionar lens? Looked around and couldn't find much, I am still tinkering with a couple of them, I tried adapting one to F mount for CF/macro and no dice, going to chop its barrel down and adapt with a helicoid next before calling it quits, are the optics bad? idea input is much appreciated.

scratchpaddy · 07-26-2022, 05:47 PM

Originally posted by junkbench

Has anyone adapted a bell & howell Trionar lens? Looked around and couldn't find much, I am still tinkering with a couple of them, I tried adapting one to F mount for CF/macro and no dice, going to chop its barrel down and adapt with a helicoid next before calling it quits, are the optics bad? idea input is much appreciated.

I'm assuming yours is plastic, 4" f/3.5? Looks like a common slide projector lens, similar to Kodak Ektanar. They come in several focal lengths, but 4" looks like the most common. I haven't used one myself, but you can expect low contrast and sharpness, nervous bokeh at all but the closest distances, and characteristic triplet soap bubbles in the right circumstances.

Someone on Thingiverse did exactly what you're trying to do, here. They have some close-up sample pictures. They had to chop off at least one inch from the lens to get infinity focus. If your lens is a shorter focal length, you will need to get it even closer to the sensor.

junkbench · 07-26-2022, 07:06 PM

Yes, it is and thank you! I'm interested in doing exactly what this guy did, very helpful. Much appreciated!.

junkbench · 07-28-2022, 07:13 AM - **1 Like**

Decided not to mess with a helicoid and just use this lens with a crudely attached F mount adapter on the old D200

Definitely has the low-element "look" to the shots, what do you guys think?

Few tests.

scratchpaddy · 07-28-2022, 05:16 PM

Originally posted by junkbench

Decided not to mess with a helicoid and just use this lens with a crudely attached F mount adapter on the old D200

Definitely has the low-element "look" to the shots, what do you guys think?

Few tests.

That's definitely better contrast and sharpness than I was expecting! Hard to judge the overall character of a lens from extreme close-ups, though. I really like the skink capture!

junkbench · 07-28-2022, 06:50 PM

Unfortunately I cant really do better than these I don't think, after seeing the results someone else got converting it with a helicoid I decided to give up on it and move on to a Graflex that seems more promising for a real conversion, so with this guy I'm just going to keep it as a fixed macro lens. I'm pretty impressed with the results given I wasn't expecting much and I can see using it given it has a fairly long working distance. I think the reason it's sharpness and such came out decent also comes down to the CCD sensor and using an expodisc.

scratchpaddy · 08-12-2022, 04:21 PM - **4 Likes**

Info dump time! I want to talk about the ISCO Ultra Star Plus series, the most modern film projector lenses you're likely to be able to find and afford. They're all bright red, easy to identify.

The series was introduced around 1999 as a minor improvement on the Ultra Star series from a decade before. The optical formulas remained very similar, with 7 elements for 45mm and greater lenses, and a much bulkier 9-element design for the wider lenses. No cemented or aspherical elements were used.

This is specifically the 60mm lens formula, but the same basic design applied from 45mm to ~~100mm~~ (edit: 95mm was the longest available focal length):

Notice how big the rear element is, even bigger than the front! This was the main change from the original "Ultra Star" to "Ultra Star Plus." According to the patents, aperture was increased from f/2.4 to f/1.9, and vignetting at the extreme corners was reduced by 61 to 73%. What they really did was increase the image circle quite a bit - now even the shorter focal lengths can be used on full-frame without cropping.

This is a double-exposure composite of the same lens, front and back, to show how much bigger the glass is in the back vs. the front. The ring on the front can be unscrewed to bring the aperture up to f/1.9, but even then, the front opening is smaller than the back.

This is the same lens compared to the Ultra Cinelux 65mm f/2. The ISCO designs after their split with Schneider were much bulkier than comparable Schneider ones.

Now, on to the pictures it takes. I used it quite a lot late last year, and I have one word for it: smooth. It's hands-down the smoothest lens I've ever used. Sometimes it doesn't even look real, the background is so smooth. Whether this is a good thing or not depends on your personal tastes.

Colors are neutral and flexible. Sharpness is very good, but contrast and flare resistance are poor for such a modern lens. Definitely not as much contrast as the Ultra Cinelux I've written much about.

I happen to like red anodized finishes, so the appearance of the lens itself is a plus in my book.

While it's bigger than the Cinelux, it's not too big to fit in a saddle bag for bike rides.

Overall, I have to say I don't like it as much as the older Cinelux. The rendering is so smooth that you might even call it boring. I used to think there could be no such thing as too much smoothness, but now I see that maybe there is a line somewhere that this lens has crossed. I like sweet, but cotton candy is a bit much. In today's world, a phone can passably simulate the background blur of a larger sensor, and the kind of blur this lens gives you is very easy to simulate. It lacks that hectic-but-pleasing character many classic lenses have which would be very difficult to fake.

I don't mind having it in my collection, though. Super-smooth is fun once in a while.

junkbench · 08-12-2022, 08:25 PM

Gorgeous results, outstanding, really smooth! How did you adapt them?

I'm currently working on gutting old M42's I acquired as a part of some lens lots and recycling them as projector lens bodies for using them for macro use.

scratchpaddy · 08-13-2022, 12:38 PM - **2 Likes**

Originally posted by junkbench

Gorgeous results, outstanding, really smooth! How did you adapt them?

I'm currently working on gutting old M42's I acquired as a part of some lens lots and recycling them as projector lens bodies for using them for macro use.

Thank you very much! I've seen others re-using the mounts, helicoids, and sometimes even the apertures of old lenses to adapt projector lenses. Seems like a good solution as long as you have one that fits.

I don't have any lenses I'd like to sacrifice, so I design and 3D print my adapters. I have a standard design that works pretty well, just changing the dimensions according to the lens. I print two pieces. One press-fits over the lens and includes a grip area and a spiral running along the outside. The second piece has a matching spiral groove on the inside and an M42 thread on the end. The focusing isn't quite as smooth as a real brass helicoid, but it's functional. I buy an actual metal M42 adapter to thread my printed part into, since threads are easier to print than a bayonet, and I'm not confident a printed bayonet would be strong enough.

I'm adapting to mirrorless (Sony), which is the only option for most shorter projector lenses. Their back focal length is too short to work on DSLRs.

Here's what they look like in real life, with the 70mm lens I used for all the pictures in the last post on the left. The electrical tape is to block light; I discovered that the red plastic I was using was not completely opaque, so that was a quick fix. On the right is a 50mm version I found early this year. The blue filament I used there happens to be perfectly opaque, even though it's a lighter color.

I added another piece to the front that has standard 49mm filter threads, so I can use regular lens caps. I guess I could just print a cap instead, but I don't like slip-over caps.

No surprise, the 50mm renders pretty much the same as the 70mm, but with a wider field of view.

As I mentioned in the last post, the "Plus" series has a bigger image circle than the original Ultra Stars and Cinelux Ultras. In those other series, 65mm was about the shortest focal length you can use on full-frame without black corners. With the Plus, it looks like all of the lenses of the 7-element type can be used on full frame. On this 50mm, there is strong vignetting, but you can still use the whole frame. The same might be true of the 9-element lenses under 45mm, but I'm unwilling to buy one to find out. They are gigantic.

junkbench · 08-13-2022, 03:22 PM - **2 Likes**

Thanks for your reply, those results are sincerely outstanding. Awesome explanation and impressive to see you carried it from concept to such results, really inspirational. I find the Bokeh of those shots outstanding, kind of ideal. Have you thought of spray coating instead of tape? maybe something like duracoat or just multi-coating with a matte black paint to solve the light issue?, just a thought. Either way, I for one genuinely appreciate seeing that.

scratchpaddy · 08-14-2022, 10:28 AM - **2 Likes**

They are remarkable lenses, for sure. I really do like them, I just like the Cinelux-Ultra a little more, and that's not saying much when the Cinelux is my current Favorite Lens Ever. You can still find them once in a while for less than $100, sometimes a lot less. I expect the original Ultra Star (without Plus) series would also give very similar rendering.

Painting might solve the translucency issue, but the easiest solution for me would be to re-print that piece with a better filament, if I get tired of the electrical tape. It was the only red filament I had at the moment, and I wanted it to still match my bike.

07-28-2022, 07:13 AM - 1 Like	#503
junkbench Senior Member Join Date: Jul 2022 Location: Ocala, FL Posts: 115	B&H 4" Trionar F3.5 Astigmatic Decided not to mess with a helicoid and just use this lens with a crudely attached F mount adapter on the old D200 Definitely has the low-element "look" to the shots, what do you guys think? Few tests. Last edited by junkbench; 08-09-2022 at 07:57 PM.

08-12-2022, 04:21 PM - 4 Likes	#506
scratchpaddy Pentaxian Join Date: Feb 2013 Location: Phoenix Posts: 3,361	Info dump time! I want to talk about the ISCO Ultra Star Plus series, the most modern film projector lenses you're likely to be able to find and afford. They're all bright red, easy to identify. The series was introduced around 1999 as a minor improvement on the Ultra Star series from a decade before. The optical formulas remained very similar, with 7 elements for 45mm and greater lenses, and a much bulkier 9-element design for the wider lenses. No cemented or aspherical elements were used. This is specifically the 60mm lens formula, but the same basic design applied from 45mm to ~~100mm~~ (edit: 95mm was the longest available focal length): Notice how big the rear element is, even bigger than the front! This was the main change from the original "Ultra Star" to "Ultra Star Plus." According to the patents, aperture was increased from f/2.4 to f/1.9, and vignetting at the extreme corners was reduced by 61 to 73%. What they really did was increase the image circle quite a bit - now even the shorter focal lengths can be used on full-frame without cropping. This is a double-exposure composite of the same lens, front and back, to show how much bigger the glass is in the back vs. the front. The ring on the front can be unscrewed to bring the aperture up to f/1.9, but even then, the front opening is smaller than the back. This is the same lens compared to the Ultra Cinelux 65mm f/2. The ISCO designs after their split with Schneider were much bulkier than comparable Schneider ones. Now, on to the pictures it takes. I used it quite a lot late last year, and I have one word for it: smooth. It's hands-down the smoothest lens I've ever used. Sometimes it doesn't even look real, the background is so smooth. Whether this is a good thing or not depends on your personal tastes. Colors are neutral and flexible. Sharpness is very good, but contrast and flare resistance are poor for such a modern lens. Definitely not as much contrast as the Ultra Cinelux I've written much about. I happen to like red anodized finishes, so the appearance of the lens itself is a plus in my book. While it's bigger than the Cinelux, it's not too big to fit in a saddle bag for bike rides. Overall, I have to say I don't like it as much as the older Cinelux. The rendering is so smooth that you might even call it boring. I used to think there could be no such thing as too much smoothness, but now I see that maybe there is a line somewhere that this lens has crossed. I like sweet, but cotton candy is a bit much. In today's world, a phone can passably simulate the background blur of a larger sensor, and the kind of blur this lens gives you is very easy to simulate. It lacks that hectic-but-pleasing character many classic lenses have which would be very difficult to fake. I don't mind having it in my collection, though. Super-smooth is fun once in a while. Last edited by scratchpaddy; 08-13-2022 at 07:14 PM.

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02-26-2022, 11:57 AM	#496
Pedro Alanis New Member Join Date: Feb 2022 Posts: 1	Originally posted by fiveseven Some of my projector lenses.....It's pretty awesome the resolution from them vs regular camera lenses. About your Kp35 1.8/100, the aluminum tube that supports the lens and has the m42 mount, what type of lens or projector does it originally belong to? About your Kp35 1.8/100, the aluminum tube that supports the lens and has the m42 mount, what type of lens or projector does it originally belong to?

07-26-2022, 02:08 AM	#500
junkbench Senior Member Join Date: Jul 2022 Location: Ocala, FL Posts: 115	Has anyone adapted a bell & howell Trionar lens? Looked around and couldn't find much, I am still tinkering with a couple of them, I tried adapting one to F mount for CF/macro and no dice, going to chop its barrel down and adapt with a helicoid next before calling it quits, are the optics bad? idea input is much appreciated.

07-26-2022, 05:47 PM	#501
scratchpaddy Pentaxian Join Date: Feb 2013 Location: Phoenix Posts: 3,361	Originally posted by junkbench Has anyone adapted a bell & howell Trionar lens? Looked around and couldn't find much, I am still tinkering with a couple of them, I tried adapting one to F mount for CF/macro and no dice, going to chop its barrel down and adapt with a helicoid next before calling it quits, are the optics bad? idea input is much appreciated. I'm assuming yours is plastic, 4" f/3.5? Looks like a common slide projector lens, similar to Kodak Ektanar. They come in several focal lengths, but 4" looks like the most common. I haven't used one myself, but you can expect low contrast and sharpness, nervous bokeh at all but the closest distances, and characteristic triplet soap bubbles in the right circumstances. Someone on Thingiverse did exactly what you're trying to do, here. They have some close-up sample pictures. They had to chop off at least one inch from the lens to get infinity focus. If your lens is a shorter focal length, you will need to get it even closer to the sensor.

07-26-2022, 07:06 PM	#502
junkbench Senior Member Join Date: Jul 2022 Location: Ocala, FL Posts: 115	Yes, it is and thank you! I'm interested in doing exactly what this guy did, very helpful. Much appreciated!.

07-28-2022, 05:16 PM	#504
scratchpaddy Pentaxian Join Date: Feb 2013 Location: Phoenix Posts: 3,361	Originally posted by junkbench Decided not to mess with a helicoid and just use this lens with a crudely attached F mount adapter on the old D200 Definitely has the low-element "look" to the shots, what do you guys think? Few tests. That's definitely better contrast and sharpness than I was expecting! Hard to judge the overall character of a lens from extreme close-ups, though. I really like the skink capture!

07-28-2022, 06:50 PM	#505
junkbench Senior Member Join Date: Jul 2022 Location: Ocala, FL Posts: 115	Unfortunately I cant really do better than these I don't think, after seeing the results someone else got converting it with a helicoid I decided to give up on it and move on to a Graflex that seems more promising for a real conversion, so with this guy I'm just going to keep it as a fixed macro lens. I'm pretty impressed with the results given I wasn't expecting much and I can see using it given it has a fairly long working distance. I think the reason it's sharpness and such came out decent also comes down to the CCD sensor and using an expodisc.

08-12-2022, 08:25 PM	#507
junkbench Senior Member Join Date: Jul 2022 Location: Ocala, FL Posts: 115	Gorgeous results, outstanding, really smooth! How did you adapt them? I'm currently working on gutting old M42's I acquired as a part of some lens lots and recycling them as projector lens bodies for using them for macro use.

08-13-2022, 12:38 PM - 2 Likes	#508
scratchpaddy Pentaxian Join Date: Feb 2013 Location: Phoenix Posts: 3,361	Originally posted by junkbench Gorgeous results, outstanding, really smooth! How did you adapt them? I'm currently working on gutting old M42's I acquired as a part of some lens lots and recycling them as projector lens bodies for using them for macro use. Thank you very much! I've seen others re-using the mounts, helicoids, and sometimes even the apertures of old lenses to adapt projector lenses. Seems like a good solution as long as you have one that fits. I don't have any lenses I'd like to sacrifice, so I design and 3D print my adapters. I have a standard design that works pretty well, just changing the dimensions according to the lens. I print two pieces. One press-fits over the lens and includes a grip area and a spiral running along the outside. The second piece has a matching spiral groove on the inside and an M42 thread on the end. The focusing isn't quite as smooth as a real brass helicoid, but it's functional. I buy an actual metal M42 adapter to thread my printed part into, since threads are easier to print than a bayonet, and I'm not confident a printed bayonet would be strong enough. I'm adapting to mirrorless (Sony), which is the only option for most shorter projector lenses. Their back focal length is too short to work on DSLRs. Here's what they look like in real life, with the 70mm lens I used for all the pictures in the last post on the left. The electrical tape is to block light; I discovered that the red plastic I was using was not completely opaque, so that was a quick fix. On the right is a 50mm version I found early this year. The blue filament I used there happens to be perfectly opaque, even though it's a lighter color. I added another piece to the front that has standard 49mm filter threads, so I can use regular lens caps. I guess I could just print a cap instead, but I don't like slip-over caps. No surprise, the 50mm renders pretty much the same as the 70mm, but with a wider field of view. As I mentioned in the last post, the "Plus" series has a bigger image circle than the original Ultra Stars and Cinelux Ultras. In those other series, 65mm was about the shortest focal length you can use on full-frame without black corners. With the Plus, it looks like all of the lenses of the 7-element type can be used on full frame. On this 50mm, there is strong vignetting, but you can still use the whole frame. The same might be true of the 9-element lenses under 45mm, but I'm unwilling to buy one to find out. They are gigantic.

08-13-2022, 03:22 PM - 2 Likes	#509
junkbench Senior Member Join Date: Jul 2022 Location: Ocala, FL Posts: 115	Thanks for your reply, those results are sincerely outstanding. Awesome explanation and impressive to see you carried it from concept to such results, really inspirational. I find the Bokeh of those shots outstanding, kind of ideal. Have you thought of spray coating instead of tape? maybe something like duracoat or just multi-coating with a matte black paint to solve the light issue?, just a thought. Either way, I for one genuinely appreciate seeing that.

08-14-2022, 10:28 AM - 2 Likes	#510
scratchpaddy Pentaxian Join Date: Feb 2013 Location: Phoenix Posts: 3,361	They are remarkable lenses, for sure. I really do like them, I just like the Cinelux-Ultra a little more, and that's not saying much when the Cinelux is my current Favorite Lens Ever. You can still find them once in a while for less than $100, sometimes a lot less. I expect the original Ultra Star (without Plus) series would also give very similar rendering. Painting might solve the translucency issue, but the easiest solution for me would be to re-print that piece with a better filament, if I get tired of the electrical tape. It was the only red filament I had at the moment, and I wanted it to still match my bike.