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Chronos => Chronos User Discussion => Topic started by: Taofledermaus on July 13, 2017, 10:08:41 PM

Title: Let's talk LENSES!
Post by: Taofledermaus on July 13, 2017, 10:08:41 PM
I admit I know very little about lenses.  When people have suggested certain lenses and adaptors,   it has just confused me even more!   It would be interesting to know
what people have used,  what has worked,   and what lenses work best for different applications like macro to zoom.   Trying to find the perfect lens can get very expensive,  so I hope
we can all learn from each other.   
Title: Re: Let's talk LENSES!
Post by: Johnny on July 14, 2017, 09:55:25 AM
My lenses so far:

Angenieux 10mm f1,8 Retrofocus
Kern Paillard Switar 25mm f1.4 (needs some modification)
Angenieux 15-150mm 1.9

All three of them have a native c-mount.

The 25mm Switar is the only one that needs some sawing of the outer frame to fit. It is because of the c to cs-mount adapter that has to be used. I think that if the camera would have a native c-mount it would not need the modification.
It is fairly easy modification to do, if you know how to use a saw or file.

All of them work fine after adjusting the back focus.
Title: Re: Let's talk LENSES!
Post by: ExaltedDuck on July 15, 2017, 10:46:53 AM
Hi TFM, I've been enjoying your content for years. 

I'm in kind of the same boat, never owned a camera before that didn't come with its only lens attached.  Well technically, I still don't (and probably wouldn't for stills unless/until my trusty WB850F dies).  I was likely the very last kickstarter and am still a few weeks away from receiving my Chronos, from the sound of things.  That hasn't stopped me from researching and shopping though.  I've taken the plunge on a Schneider Variogon 18-90mm f/2 from ebay and have already received a Belle & Howe Angenieux 25mm f/0.95 from Victoria Camera Traders (great guys and fast service there, btw).  Neither broke the bank, with both priced about the same as a new sample of the computar 12.5-75mm.  I'll hope the CS-C adapter I plan to get with my Chronos backsaces them properly, but we'll have to wait and see.

I was aiming to find lenses meant for 16mm and super-16.  The frame size of 16mm film is almost a match to the 2/3" sensor on the Chronos so there should be no vignetting and only a minimal cropping factor (a 50mm focal length lens for 16mm film frame should produce an image like a 58mm focal length lens on a 2/3" sensor).  Super-16 is pretty reasonable as well (a 50mm would behave like a 66mm).  Some good info is here (http://neilvn.com/tangents/full-frame-vs-crop-sensor-cameras-comparison-depth-of-field) and here (https://en.wikipedia.org/wiki/Image_sensor_format).  I've been trying to think about the physics of it and while I think I kind of understand how the mismatch alters the field depth to behave like a different f-stop, I am inclined to believe this wouldn't have much impact on the light gathering performance. (if a 4/3" 50 mm f/2 lens is on a 2/3" sensor, we can expect it produce an image framed like 100 mm lens with the field depth of an f/4 aperture but I *think* it would provide the same contrast and brightness as though it were still on a 4/3" sensor at f/2. If anyone knows better, please, by all means, correct me. :) )  I've also noticed there's quite a bit of interest for vintage lenses in the Blackmagic Pocket Cinema Camera communities... its sensor is between 16mm and super-16 so their findings are quite valuable to us, as well.

Anyway, thanks for all the entertainment over the years.  That headspinning Chakotay still has my mind reeling like a block of clay after a silly putty slug. Once my camera is in, if you ever want a second angle, I'd be willing to make the drive from OC up your neck of the woods. Might give me the impetus to finally get my BFR45-70 fixed (or just say screw it and haul up the 460 instead)
Title: Re: Let's talk LENSES!
Post by: nik282000 on July 15, 2017, 04:55:06 PM
C and CS mount lenses are an easy way to go but I have found that unless you pay "real" lens prices you are going to get quality somewhere between security camera and VHS, you get what you pay for.

I have been using a pair of C-mounts, an 8mm f1.3 and a 16mm f1.4 which are both good for a normal field of view, catching what you might expect to see when looking an an object within a few meters of the camera, the 8mm allowing you to fit an ~1m object in view at a distance of 1m.

For close cropped shots I have been using manual focus SLR lenses with a C-mount adapter, lenses like a 50mm f1.4 are great for catching outdoor subjects (birds or squirrels in a park). With the 50mm an object ~1m wide will fill the screen at a distance of 6m.

If the 50mm lens lets you focus at distances of 1m or less you can use it for macro shots of large insects, with an 80mm+ lens you can capture fairly small insects. If your lens wont let you focus at very short distances you have a couple of options, first is to buy a macro filter, these fit on most SLR lenses and make it so you can focus very close (almost touching the lens). If you don't want to use a macro filter you can use macro-rings/extension rings, these move the lens slightly farther away from the camera which makes the lens focus closer, they are made specifically for each lens mount BUT if you want to just hack it you might be able to get away with stacking 1 or 2 CS to C mount adapters. This will have the same effect as macro rings but may cut off the corners of your image.

For insanely high magnification I have used a 400mm f8 lens on the Chronos, it let me see a golfer teeing off from nearly 1km away and still have the ball visible. An ~1m object would have to be 50m away in order to fit on the screen at that point.

Finally, all of the "will fit on your screen" numbers only apply when you shoot at 1280px image width, when you increase the frame rate and shrink the resolution you will need to use lenses with shorter focal lengths to get a wider field of view. For example if I can see my whole shot with the 16mm lens at 1280x720 I will have to switch to the 8mm lens if I want to film at 640x360.

Hope this was helpful.
Title: Re: Let's talk LENSES!
Post by: Simon on July 15, 2017, 07:40:36 PM
I'm hoping to get away with my Canon lenses - a 17-35/2.8L, 70-200/2.8L. 

Bought a Fotodiox C to EF adapter - nice quality. All I need now is the camera.

Also have a 17-85 Macro that was chucked in for free with a 2nd hand body I once bought because its electronics would fail and lock the body - glad I kept it.

I will be mainly analysing the strike of a golf ball and prelim calcs showed me the 17-35 will be good. The minimum focusing distance of 0.42m shouldn't change because of the crop, but the crop factor magnification is a godsend in making that golf ball occupy more pixels, so more accurate measurements can be taken.

Like ExaltedDuck, I believe the light gathering performance won't be affected by the crop - sure less total light will hit the sensor but each sensor pixel will still get the same exposure as it would have if the sensor was full frame.

I have done macro work before taping the 17-35 backwards to the 70-200, but depth of field is just too small for anything moving. I had the center of a fly's eye in focus, the outer parts way out of focus it is that small.
Title: Re: Let's talk LENSES!
Post by: Electra on July 17, 2017, 02:49:42 AM
My collection is the 2/3"  12mm, F/1,6 Prime that David offered with the kickstarter. (This will be the lens that will stay on the camera when it's packed away.)
* A Secondhand Cosmicar 22-66mm, F/1.8 Zoom 'TV Lens' that should be at least full 2/3" or better frame.
* AU$75 8-50mm F1.4  1/2"  Lens from Aliexpress that is our 'cheap lens' test.
* And currently at a friend's place but promised to me, a "Zenit Photosniper" with a Tair-3AS 300mm f/4.5 lens that I have no idea what it'll be like to use but at least in full sunlight looks like it might work up to about 4000fps.

In 2-3 weeks I should have test footage with the first three up. The last one, I have no idea when I'll actually get it.  I'll update when I have info.
I'm very interested in what other's experiences are too.
Title: Re: Let's talk LENSES!
Post by: akeeh on July 17, 2017, 03:23:14 AM
My collection of C-mount lenses is as follows, I will post some test results with these (normal use and macro use with extension tubes) after I finally receive my camera, hopefully in the next coming weeks:
- VT Lens 12.5mm f/1.3
- Canon TV Lens VF 25mm f/1.4
- Tamron 25mm f/1.6
- Canon TV Lens PHF 35mm f/1.2
- VT TV Lens 50mm f/1.3
- Canon TV Lens VF 50mm f/1.8
- Two somewhat identical lenses with different manufacturer engraving: VT TV Lens 75mm f/1.3 and eneo TV Lens 75mm f/1.3
- Collection of extensions tubes and a 2x extender for C-mount
- Different microscope lenses and a C-mount adapter for them

I also have a Nikon F to C-mount adapter and I'll do more tests at least with these Nikon lenses: 35mm f/2.0D, 50mm f/1.4D, 55mm f/2.8 macro and a 180mm f/2.8
Title: Re: Let's talk LENSES!
Post by: Dan Kanes on July 20, 2017, 04:44:23 PM
(a 50mm focal length lens for 16mm film frame should produce an image like a 58mm focal length lens on a 2/3" sensor).  Super-16 is pretty reasonable as well (a 50mm would behave like a 66mm).  Some good info is here (http://neilvn.com/tangents/full-frame-vs-crop-sensor-cameras-comparison-depth-of-field) and here (https://en.wikipedia.org/wiki/Image_sensor_format).  I've been trying to think about the physics of it and while I think I kind of understand how the mismatch alters the field depth to behave like a different f-stop, I am inclined to believe this wouldn't have much impact on the light gathering performance. (if a 4/3" 50 mm f/2 lens is on a 2/3" sensor, we can expect it produce an image framed like 100 mm lens with the field depth of an f/4 aperture but I *think* it would provide the same contrast and brightness as though it were still on a 4/3" sensor at f/2. If anyone knows better, please, by all means, correct me. :) )

A lens's focal length is a different way of describing its Magnification effect.

A 50mm lens made for a 35mm camera will offer the same field of view as a 50mm lens made for 2/3" or 16mm.l [FOR A GIVEN SENSOR SIZE]

The angle of view is sensor dependent.

There are other factors that affect usability / quality of image - such as vignetting if the elements or element holders are not appropriatelt sized for the format.

This should help you understand :

http://blog.abelcine.com/2010/05/14/a-lens-is-a-lens-is-a-lens/


https://youtu.be/ZF4GSMw1CeQ

Personally I'm interested in applying a Focal Reducer to the Chronos to see what we can get out of it.
Title: Re: Let's talk LENSES!
Post by: BiduleOhm on July 21, 2017, 04:04:43 AM
A 50mm lens made for a 35mm camera will offer the same field of view as a 50mm lens made for 2/3" or 16mm.

Actually, no, the "A lens is a lens is a lens, and it doesn’t know what size sensor or film gate is placed behind it." is exactly why we have the crop factor. Please see https://photographylife.com/what-is-crop-factor and https://www.bhphotovideo.com/explora/photography/tips-and-solutions/understanding-crop-factor and https://en.wikipedia.org/wiki/Crop_factor

This means that for our 2/3" sensor the crop factor is almost 4, so a 50 mm lens on 2/3" sensor will have the same effect as a 200 mm lens on a 35 mm sensor, and what ExaltedDuck said is spot on (except the reference sensor isn't 4/3" but 35 mm).
Title: Re: Let's talk LENSES!
Post by: John DeLonghi on July 21, 2017, 06:51:21 AM
A good focal reducer would make a lot of sense for the Chronos. Especially if, like me, you've got some decent 35mm glass and want to use it instead of investing in C mount lenses.

Has anyone tried one yet?
Title: Re: Let's talk LENSES!
Post by: BiduleOhm on July 21, 2017, 12:08:13 PM
Even without a reducer you can still use it without any problem, you just need to put the camera farther away and/or use lens with a smaller focal length ;)
Title: Re: Let's talk LENSES!
Post by: Dan Kanes on July 21, 2017, 07:35:11 PM
Sorry , no.

Crop factor is a bad idea that confuses people about how lenses work.

What he was saying is you need a 50mm lens made for a 2/3" sensor, and that a 50mm lens for a 2/3" sensor would have a different field of view than a 50mm lens made for a 35mm sensor.

Go get a 50mm 16mm format lens, a 50mm 35mm lens, and a 50mm 2/3" lens - they will all provide the same field of view on the Chronos - because they are ALL 50MM LENSES.

Now, your understanding of effective crop factor is sort of an okay way to translate concepts - but you get into a real shitstorm when you realize there are a lot of 35mm formats and you start making decisions about a shot size on incorrect understandings of how lenses function.

It's better to think in "wide, normal, and telephoto" terms if you're just starting out.

A wide on the Chronos could be anywhere from 6mm to 12mm pretty much.

A medium on the Chronos would be 16 , 25 or 35 (with 35 being pretty long actually)

Telephoto could be a 50 and above on Chronos.

On a 36x24 film format a 50mm is a "medium"

And on a super-35mm motion format a 35 is pretty much "medium"

You could try learning with this whole crop factor BS that photogs often lean heavily on, but if you want to learn the more scientific way that won't leave you with incorrect assumptions - watch the Abelcine video with mitch gross that I posted.

I hate crop factor because it always confuses people new to motion imaging and is akin to trying to translate every word in a foreign language before learning a native language.


A 50mm lens made for a 35mm camera will offer the same field of view as a 50mm lens made for 2/3" or 16mm.

Actually, no, the "A lens is a lens is a lens, and it doesn’t know what size sensor or film gate is placed behind it." is exactly why we have the crop factor. Please see https://photographylife.com/what-is-crop-factor and https://www.bhphotovideo.com/explora/photography/tips-and-solutions/understanding-crop-factor and https://en.wikipedia.org/wiki/Crop_factor

This means that for our 2/3" sensor the crop factor is almost 4, so a 50 mm lens on 2/3" sensor will have the same effect as a 200 mm lens on a 35 mm sensor, and what ExaltedDuck said is spot on (except the reference sensor isn't 4/3" but 35 mm).
Title: Re: Let's talk LENSES!
Post by: ExaltedDuck on July 22, 2017, 12:07:19 AM
FWIW, The way I think of it is in terms of the resolved image circle's diameter and whether that is relatively similar to the sensor's widest dimension (diagonal).  If the circle is smaller, there will be vignetting, if it's similar, the lens should work as expected, and if it's larger then the edges of the resolved image are not captured, reducing the field of view.  I tried to keep the language similar to how photographers describe things because that is what we will find if we look into photo/videography forums for ideas as to what might work on our cameras as well as being consistent with how the topics were approached in the links I offered. 

Anyhow, I don't want to jack the thread from its original intent: discussion of which lenses we've chosen for our cameras, and why.  I wanted to try a prime and a zoom, I wanted something native C-mount to (hopefully) minimize hassle, I wanted it to be intended for at least a 16mm film size to minimize likelihood of vignetting but no bigger than super-16 to ensure that as much as possible of the objective lens's light gather capability is focused on the sensor. I wanted to find something not much more expensive than the Computar 12.5-75 and I was willing to settle for maximum aperture around 1.8-2.0 as long as it was from a notable name in optics.  I looked at many possibilities on ebay, bhphotovideo, and a few other sites. I preferred to buy second-hand so that if I am unhappy with the results, I should be able to recoup my costs and redirect the money to something else. Those models I chose met all of my criteria.  I have high hopes for both and anxious to try them out when my camera gets here in a few weeks.
Title: Re: Let's talk LENSES!
Post by: BiduleOhm on July 22, 2017, 03:45:22 AM
@Dan Kanes I'll not argue more on the subject and I'll wait to have the camera and some F-mount lenses (already bought a F to C mount adapter) to compare to some real C-mount lenses (actually the Computar 12.5-75 mm and some other small lenses for CCTV) so I'll see by myself who is right.

@ExaltedDuck As said I have the Computar 12.5-75 mm f1.2 which should be perfect for most shots (excepted macro maybe) and I have some small CCTV lenses I was using for CCTV but maybe one of them will do good on the Chronos (or maybe they're all too crappy...) :)
Title: Re: Let's talk LENSES!
Post by: Electra on July 23, 2017, 03:15:33 AM
I'd have thought that the focal reducer/speed booster would have been more useful because it gives you another F/stop?  Are there such things for C mount or is this going to be Krontech's next custom made accessory? :)
That's why I was looking at them. If you take a lens for a 4/3 or full frame sensor and focus all that light on the 3/4" sensor the Chronos has, it'll give you much better light gathering capabilities, the one thing that your always fighting for with high speed cameras.
Getting second hand glass for much larger sensors is fairly easy due to the SLR market, but a lot of the light is lost using it with the smaller sensor size. It would be nice to get some of it back even if it means quite drastically changing the lens focus length.
Title: Re: Let's talk LENSES!
Post by: BiduleOhm on July 23, 2017, 04:50:49 AM
I searched for a bit and I can't find a F to C-mount focal reducer. I guess we need to ask on photography forums if this kind of focal reducer exists.
Title: Re: Let's talk LENSES!
Post by: Electra on July 23, 2017, 09:04:14 AM
Some info on how they work: http://rubenkremer.nl/2013/11/26/focal-reducers-speedbooster-lens-turbo-and-light-cannon/
https://beomagi.blogspot.com.au/2014/01/focal-reducers-on-dslrs-and-light-gain.html
And a bit about them on more conventional cameras:  http://nofilmschool.com/2014/07/cheaper-budget-metabones-speed-booster-excell-1-fotodiox-pro

I did find: http://agenaastro.com/agena-c-cs-mount-focal-reducer.html
There looks to be a whole range for telescopes. Might be worth looking down that path.

Because we'll be doing something non-standard, I'm expecting half research and half trial-and-error to get this working, but unless I've got something very wrong, it should possible.
Depending on the lens/adapters, we may have to find native reducers for our lenses and then something like that c mount one for the final to get past the adapters narrowest point. One thing that might help is that C mount is made for 1" sensors(or close to it) and we have a 2/3" sensor, so even if we loose some light, concentrating what we can use further might still help.

I know there'll be looses in the optics and I'm expecting most bother, but it's too interesting a path to not at least experiment a bit.
Title: Re: Let's talk LENSES!
Post by: BiduleOhm on July 23, 2017, 10:07:34 AM
Yeah I found this one too but it's for a 1.25" telescope mount, I don't think it'll be very useful here unfortunately.

Yes, if you can find the proper reducer then it'll work no problem. The main problem is to find one for a C or CS mount and where we can mount a Canon/Nikon lens (EF or F mount) on the other side even if we need another adapter. For now I only found 1.25" to C mount reducer or some DSLR to another DSLR reducer.
Title: Re: Let's talk LENSES!
Post by: nik282000 on July 23, 2017, 06:02:37 PM
Hmm, a speed booster is an element on the back of a lens compresses the image circle. So what do you call an element in front of the lens that compresses the image circle? A fisheye filter!

If you can find a strong enough fisheye filter it would give you both a wider FOV and more light per pixel on the sensor (provided that the aberrations from filter aren't too bad). Given that the Chronos sensor is 2/3" many of the aberrations from a filter may fall outside the sensor area anyway. Looks like there are a couple on ebay/amazon for <$100 but I have never personally tried one.

Any thoughts?
Title: Re: Let's talk LENSES!
Post by: John DeLonghi on July 24, 2017, 06:08:45 AM
My experience of fitting wide angle adapters to the front of lenses has never been particularly good. The optical performance is usually not very good and as they are often designed to be 'universal' they take no account of the construction of the lens they're being fitted to.
There are some good ones around but they are quite expensive and I don't think the end result will be as good as if we can find a focal reducer.

I also spent some time over the last few days trying to find a decent reducer to fit the Chronos with no real success. There won't be any demand for such a thing at the moment, but if there was a way to adapt something like a Metabones Speed Booster, I'd go for it.

I think it should be technically possible to adapt a Speed Booster designed to take Nikon G/F mount lenses to fit the Chronos, but the missing link is converting one of their camera-side mounts to C/CS.
Title: Re: Let's talk LENSES!
Post by: BiduleOhm on July 24, 2017, 11:32:21 AM
What's their camera side mount?
Title: Re: Let's talk LENSES!
Post by: John DeLonghi on July 25, 2017, 03:54:21 AM
They do various versions, all for mirrorless cameras such as Leica M/S Sony E, Fuji X.

I reckon the best bet might be the versions they do for MFT or Blackmagic as those are small diameter mounts to begin with. It might be possible for someone to machine a mounting ring which would replace their one and convert directly to C mount.

There are lots of adapters out there for fitting C-mount lenses to MFT cameras, but not the other way around.
Title: Re: Let's talk LENSES!
Post by: nik282000 on July 25, 2017, 10:24:48 AM
It all has to do with the back focus distance, with mft and e-mount I believe the cmount adapters extend into the body of the camera. To make an mft or e-mount to c-mount I think that means there will be a couple mm of space in which to make an adapter.

Welp, looks like the flange to sensor distance for all 3 mounts are 17-19mm, not much room to work but not impossible.
Title: Re: Let's talk LENSES!
Post by: John DeLonghi on July 25, 2017, 10:55:02 AM
That's why I thought it might be possible with one designed for MFT in the first place. It's bound to be tight, but 17.5mm seemed enough to me looking at another C mount camera I have here.

It's the engineering of an adapter which is going to be tricky and it would be an expensive mistake if it didn't work.

I do feel the optics of the Metabones reducers are worth the money and could give excellent results if we could get one to fit. I've emailed them to ask if they think it's possible, so let's see if I get a response.

Looking at lens options generally, I'm also looking at Kowa C-mount lenses as there are a few Blackmagic camera owners using them and they have a good reputation for quality. There are plenty of old C-Mount lenses around on ebay but I suspect quite a few of them are not worth bothering with.
Title: Re: Let's talk LENSES!
Post by: Sorchey on November 08, 2017, 07:32:04 AM
Hey everyone!


First of all, I really don't know much about lenses.

I've purchased this lens (http://www.krontech.ca/store.html#!/Fujian-25mm-f-1-4-C-Mount-lens/p/77244591/category=21981409) in an online auction similar to ebay, since it was really cheap and had some good reviews. After arriving today I wanted to try it out, but I couldn't get the mounted lens to focus at all. I have the feeling that the lens is malfunctioning, but maybe one of you can give me some tips.

If I unscrew the lens and simply hold it in front in a distance of about 2-3mm, I get a sharp image. But even then, turning the focus ring doesn't seem to change much.

In general: Is a spacer ring needed for this lens?
Title: Re: Let's talk LENSES!
Post by: tesla500 on November 08, 2017, 11:39:11 AM
Hey everyone!


First of all, I really don't know much about lenses.

I've purchased this lens (http://www.krontech.ca/store.html#!/Fujian-25mm-f-1-4-C-Mount-lens/p/77244591/category=21981409) in an online auction similar to ebay, since it was really cheap and had some good reviews. After arriving today I wanted to try it out, but I couldn't get the mounted lens to focus at all. I have the feeling that the lens is malfunctioning, but maybe one of you can give me some tips.

If I unscrew the lens and simply hold it in front in a distance of about 2-3mm, I get a sharp image. But even then, turning the focus ring doesn't seem to change much.

In general: Is a spacer ring needed for this lens?

A CS-C ring is required for this lens, yes.
Title: Re: Let's talk LENSES!
Post by: Martin on December 18, 2017, 04:11:58 PM
Greetings fellow time travelers,

I think this belongs here, came up again in a PM this evening.
I found this way back, when I was still waiting for the Chronos to arrive and researching native lenses:

http://www.ebay.de/itm/142138567245?orig_cvip=true

It's an f/0.7 C-Mount 50mm lens by Fujinon.

IIRC that's very close to the "practical" limit. It was too expensive to just "shop and test" it..
It "could" have been incompatible (I heard about some c-mount lenses lenses which won't work on the Chronos, don't remember the specifics. Protrusion issue into the camera body? See image 5 for example..).
AND notice the lovely "-TV" tag. Would've been too risky ;)
(It may have been vastly overprized as well.)

Here's some explanation why you won't find much faster lenses:
https://www.youtube.com/watch?v=84ZXfviMBFE

And this was just a marketing stunt without actually producing anything usable:
https://petapixel.com/2013/08/06/carl-zeiss-super-q-gigantar-40mm-f0-33-the-fastest-lens-ever-made/

;D

All the best
Martin
Title: Re: Let's talk LENSES!
Post by: Nikon1 on February 27, 2018, 05:23:43 AM
Greetings fellow time travelers,

I think this belongs here, came up again in a PM this evening.
I found this way back, when I was still waiting for the Chronos to arrive and researching native lenses:

http://www.ebay.de/itm/142138567245?orig_cvip=true

It's an f/0.7 C-Mount 50mm lens by Fujinon.

IIRC that's very close to the "practical" limit. It was too expensive to just "shop and test" it..
It "could" have been incompatible (I heard about some c-mount lenses lenses which won't work on the Chronos, don't remember the specifics. Protrusion issue into the camera body? See image 5 for example..).
AND notice the lovely "-TV" tag. Would've been too risky ;)
(It may have been vastly overprized as well.)

Here's some explanation why you won't find much faster lenses:
https://www.youtube.com/watch?v=84ZXfviMBFE

And this was just a marketing stunt without actually producing anything usable:
https://petapixel.com/2013/08/06/carl-zeiss-super-q-gigantar-40mm-f0-33-the-fastest-lens-ever-made/

;D

All the best
Martin

I own a Set of Schneider-Kreuznach Xenons, 17mm, 25mm and 50mm
All of them are quite fast and have a f/0.95 Aperture and are native C-Mount.
The 17mm is built for 2/3", but almost covers the Nikon1 Sensor. It also prodtrudes extremely far into the Camera Body, and i had to do some extreme Modifications to my Nikon J5 to make it fit.
The 25mm ist for 1" but mostly covers MFT.
The 50mm is not exactly known for what Format it is built, but covers FullFrame with some Modifications.
I would realy recommend, if anyone want to buy such a Lens, to do some proper Research about those old Lenses and the Images they produce and maybe try them on Location when buying if that is possible.
Because some (or even most) of those old, extreme fast Lenses can produce quite some funky Results you might not like.
I realy like the Look those Lenses make, but that is up to personal taste.
That said, i also keep a set of more modern, (not quite as) fast Lenses for every Focal Length, in case i need Images with a "Cleaner" Look or for realy difficult Light situations, if i dont want Flares and all that stuff.
.
Also keep in Mind:
f/0,7 is just one full Stop more Light than f/0,95. And f0,95 is again just one full Stop faster than f/1,4.
That means your 50mm 1.8 or 1.4 is plenty of a fast Lens for its commonly cheap price.
You can get something like a SMC-M PK 50mm f/1.7 for like 20€ or even less, if you spend some time searching the internet.
That is a realy sharp and reasonably fast Lens.
And compared to the Prices for your average f/0,95 (or faster) Lens that is just no Question what to get, unless you realy know what for and why you would need those Ultra-Fast Lenses.
Mostly it is just easyer to add Light to whatever you are filming.
Or just use Sunlight +maybe Reflectors & Diffusors, if that is a Option.
.
Depends on what you want capture, it may realy be possible you find yourself someday in a situation, where you cant just add Light and also cant use other camera settings for technical (or other) Reasons, like Framerate and Distance or the scale of your Shot.
Even then those Lenses Wide open can completely "destroy" your image in terms of contrast and so on.
So you will find yourself sometimes maybe even stopping those down slightly to like f/1.4 or f/2 (or even further) if you want to use it for someting else than cinematic images. Technical Imaging for example.
And then you could just use any other Lens as fast as f/1.4 or f/2
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I have to say those Schneider-Kreuznach Xenon Lenses are Realy sharp, even wide open. Maybe some of the sharpest 0,95´s you will get, especialy considering the Age of those.
BUT they loose a Lot of Contrast when wide open, make Flares and quirky bokeh, and some other stuff. And i REALY like that.
Not all of those old superfast Lenses are Sharp Wide open!!! So at least get some high Quality Test images or references of People, that used those Same Lenses you want to buy.
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And i have to say, i allready find that 50mm f/0,95 Lens Stupid Hard to focus, because of how shallow the Focal plane is.
I never got into the joy of playing with faster glass (that had a proper Mount and could focus to infinity) yet, but i would be realy curios, what it would be like to use & focus those even Faster Lenses.
I am realy used to manual Focusing, but that Lens may be the Hardest one to properly Focus, out of those that i own.
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SUMMARY: Know what you are doing if you buy Lenses like this, because Stuff is expensive.
Title: Re: Let's talk LENSES!
Post by: baseballcam on March 27, 2018, 11:49:12 AM
hello fellow time travelers,

looking to shoot some baseball games, maybe the pitcher, from far away (maybe 120-150 feet). Looking for a compatible lens for the chronos but having a hard time purchasing with any confidence.

if anyone can offer any recommendations it would be greatly appreciated
Title: Re: Let's talk LENSES!
Post by: Nikon1 on October 13, 2018, 01:57:56 PM
https://www.ebay.de/itm/ERNITEC-Auto-Iris-Lens-f1-3-5-6mm-2-3-25mm-Gewinde-/232904148794
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Here is an very wide Lens for an reasonable Price for anyone searching for one.
CS-Mount, so no Distance Ring required.
Lens is auto-Iris so you propably cant change aperture on the go and most likely will need to use it wide open all the time.
Title: Re: Let's talk LENSES!
Post by: BiduleOhm on October 14, 2018, 01:44:52 AM
This kind of lense usually take a 9-12 V power and the composite video signal. In short they look at the average level of the video signal to know the luminance and open/close the iris. You can see in the photo of the datasheet it's the case here and you even have the color of the wires matched with what they do. So by sending a 0 to about 1 V DC voltage at the video input you should be able to control the lense iris.

I plan to test this when I get this lens (thanks for posting the link BTW ;)) and post a simple schematic if you want to do the same.
Title: Re: Let's talk LENSES!
Post by: Nikon1 on October 14, 2018, 02:02:09 AM
Oh, Wow, Thanks for the info. I never knew how those Auto-Iris Lenses Worked. I also never actually owned one myself. But good to know anyways.
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I wont buy that lens, since it is for 2/3", which is perfect for the Chronos, but wont cover the 1" sensor of my Nikon1 completely without vignetting (Just guessing). Just stumbled across this thing on Ebay and found, that it would be worth posting here since the Lens is most likely good brand Quality and quite Cheap, very wide and a good Fit for the Chronos. Also, most people would have the 12-75mm Lens, so an 5,6mm like this would be an Nice addition to anyones Camera, both for wide-Angle/ Tight spaces and also for lower Resolution/ very high-framerate Shooting.
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If someone buys this, and happens to own some Kind of mirrorless Camera, it would be very nice if he could take an image with this lens, if the image Circle of the Lens is 15mm or bigger, i will also get one of those. Otherwise its not worth it for the use on the Nikon1 for me.
Title: Re: Let's talk LENSES!
Post by: BiduleOhm on October 14, 2018, 02:27:57 AM
There's also the ones who don't have any electronics inside (they're called DC iris; the one you posted is called video iris) and the camera do all the job, they have a 4 pins square connector instead of the mini-DIN like connector; 2 for motor and 2 for feedback (and both are coils like in a galvanometer so be careful with what you power it).

Title: Re: Let's talk LENSES!
Post by: nik282000 on February 01, 2019, 01:51:51 PM
The Fujinon 2.7mm F1.8

I wanted a really wide lens so that I could get a reasonable field of view when using higher frame rates and this lens looked like it would do the job. You can find this lens on ebay starting around 150CAD, there are some sellers that have it listed for WAY more than that, it's not worth that much. If you want one keep looking and wait it out until you can find one for 200 or less.

The Good:
-It's wide! If you are using the full width of the Chronos' sensor you will get a 180degree wide field of view!
-It's fast! F/1.8 means it delivers a very bright image, it captures a lot of light.
-It's small, around 50mm long which is bigger than most c-mount lenses but WAY smaller than the SLR lenses I use.

The Bad:
-Fixed focus, there is no way to adjust the focus other than using the backfocus on the Chronos, you'll need to keep an allenkey.
-It's a little soft, being an F/1.8 it is a little soft but I didn't find it any worse than the other c-mount lenses I use.
-The price, brand new (with the adjustable aperture) it seems to go for 400 CAD and up, hold out for a used one on eBay if you can.
-Image circle, when using the full Chronos sensor the image circle doesn't entirely fill the frame, but given the field of view it's not a huge problem.


Setting the backfocus can be a little finicky, I found it was best to set the Chronos to a small crop (128x128 ish) and then adjust the focus. My copy came with a weird cap/adapter and 2 very thin plastic rings, adding just one of the rings will take the focus from infinity down to 1m or less, this lens is VERY sensitive to changes in distance between the lens and the sensor. Overall I am impressed, it's well built and despite being a little soft it more than makes up for it by giving a 180 degree field of view. For reference, in the last photo the lens is touching the glass of the window and yet you can still see the edges of the frame.
Title: Re: Let's talk LENSES!
Post by: Nikon1 on February 02, 2019, 08:08:43 AM
I also have that same Lens, the Fujinon 2,7mm 1.8. Mine Is also without the Aperture, because that one seemd to expensive back when i bought it.
It really is a great Lens and i always keep it in my C-Mount Prime Lens-Set when i Need an Crazy wide FOV Lens.
Got mine for somewhere Between 120 to 180€ about two Years ago. Cant remember the price Exactly.
Cant quite agree on it beeing a Soft Lens, used it on my Nikon J5, which has an 1" Sensor and 20 Megapixel and, well it is a bit soft towards the corners, but overall it can produce very sharp Images, even at such high Resolution. Could Upload Samples, if interrested, just dont have any high-Quality samples at the Moment because i use this Lens VERY rarely.
If you dont get sharp images from this Lens, check if your Focus is actually Correct, since this Lens Has somewhat of a shallow Depth of Field for beeing that wide.
I focus mine simply by unscrewing it from The C-Mount, works nice For me, since i mostly shoot handheld with it. If you plan on using it on an Tripod or alike, you are Quite Limited to whereever your Focus is, or need some percise C-Mount Rings to set The Focus Correctly. If you use The "just unscrew the Thing from the Mount"-focusing-Method, you also have an Pretty Crazy Fisheye-Macro-Lens (could produce very interresing Results with this!) which could focus up to stuff Touching the Front Lens Element and even beyond that... Just dont Drop your Lens if it comes Loose from the Unscrewing...
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I also Wanted and Needed a VERY WIDE Lens (That covers my Nikon´s J5 Full 1" Sensor while not beeing fisheye) for A long time, and finaly found something, that i am Happy with.
My Azure 6,5mm f/1.4 combined with an Rehoused old German Wide-Converter, togehter producing an 4,55mm f/1.4 Non-Fisheye-Lens, covering an full 1" Sensor (15,8mm Image Circle)!
Bevore i Got /Built this, i Tried a lot of other Lenses just naming a few here:
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- 8mm 1.4 Kowa for 1". Amazing Lens, super Sharp, extremely well built, Love this Lens, most used Lens of my very wide ones, but sometimes just not wide enough.
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-6,5mm 1.8? TV Lens (not quite Sure anymore, what the Exact numbers Where). Got that one for 30€ on ebay, not very sharp and also produces somewhat lame Looking images, Cracked the Front Element while Trying To Manufacture a mount for an 0,7x Wide-Angle Converter. Gave it to nineff, because i allready orderd the Avenir back then. For around 30€ good value for the money, but i wasnt toooo happy about sharpness...
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-6,7-13mm 1Nikkor Lens. Very Sharp Lens, BTW, some handsome Person could use This Lens on an Chronos or even Rehouse it. (if you want to do this, keep in mind, it is a Focus-By wire only! Lens and hasnt even an aperture dial or something, can be done with heavy Modification and/ or some workarounds, but not very fun thing to do) I Built an adapter-Clamp for my 0,7x Wide-Converter, and that worked well, but it bothered me that this lens was just an f/3,5-5,6 and therefore it was only useable in Daylight...
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2,7mm 1.8 Fujinon. See above
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4,2mm 1.6 Pentax. Sharp enough lens, very wide, not as Wide as the Fujinon, but stil impressive for such a small Lens. but also Fisheye. Also got this one for 30 to 40€ incl. Shipping, good Value For this price. Will make a Circular image and should even on the chronos produce images with Black corners.
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And why did i finaly buy the Azure 6,5mm 1.4, and not the Kowa 6mm 1.8 or one of those old Tegea 5,9mm C-mount- Cinr Lenses and the Like?
Well, the Azure goes for around 200 used and a bit more new (maybe up to 300 including shipping), is a half stop faster than the Kowa, has an Filter Thread, on which a can Mount an Wide-Angle Converter, while th Kowa 6mm only has that Huge, Sticking out, Front Element, With which i had to worry all day about not getting it damaged, and no easy way of attatching an Wide-Converter. Also, the Kowa is a Good bit Bigger, heavier and costs about three times that what the Azure Will cost you. Kowa 6mm 1.8: New around 700, not including shipping and up to 600 used.
Those Tegea and alike are mostly overpriced and they are huge Heavy beasts of Lenses... Havent used one yet, but heard, that those also should not be the Sharpest Lenses ever made. Those Could be worth the money, if you absolutely need or want That Cinematic Look, but i doubt that.
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So i bought the Azure 6,5mm 1.4.
This lens is Crazy Sharp, has quite some Contrast to it and an Punchy Look (very clean, not as bold of an contrasty and vibrant Look as the Kowa 8mm 1.4 has). Also, it is super small and has high overall image Quality, Low distortion, minimal Vignetting an is sharp up to the corners and covers an full Nikon 1 J5 1" Sensor without problems. I think this is the best Value for Money and also about as wide as you can get your Lens, bevore you get massive Vignetting, crazy big, heavy and Expensive Lensdesigns or Fisheye-Lenses (At least thats the case for 1" Sensors. Not sure about the bit smaller 2/3" Sensor of the Chronos, there may be an even Wider affordable Option available for that....). Somehow, this Lens Reminds me A LOT of the Cine-Nikkor 6,5mm 1,4 for 16mm Film... not just the Specs, also the Size and the Design of the Lens Body...and its Performance... Havent yet got an 6,5mm Cine-Nikkor in my hands to compare it to (Since those are Crazy rare Lenses and very expensive), but it could be a Plain Copy / Remake of the Cine Nikkor...?
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As said, i paired this Azure 6,5mm 1.4 with an 0,7x wide-Converter in an Self Built New housing, togehter making it to about an 4,55mm 1.4 for 1", Non Fisheye.
It is sharp, but mostly in the Center. Looses some Sharpness towards the edges and also has some visible Distortion ( Still WAY better Than any Fisheye-Lens).
Since the Converter itself is also very small, the whole thing is rather compact and Light. Certainly not as good as an Good Brand Full-Frame Rectlinear Super-Ultra-Wide-Lens but also a lot smaller, Faster (f 1.4) and cheaper.
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For Samples, just ask, im a bit to Lazy to do a ton of Images here, without knowing if anyone is actually interrested in it.
Title: Re: Let's talk LENSES!
Post by: Nikon1 on December 22, 2019, 01:02:53 AM
Quick update about Lenses for the 2.1, since everything here was only Relevant, bevore the 2.1 came out...:
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The 2.1 has an bigger Sensor, that means, if you want to use The Full Resolution, you need different Lenses than for the 1.4!
If you want to know, if some C-Mount Lens you found on E-Bay or something like that will fit the 2.1 just do a bit of Research on the Web, some Years ago there was the Whole big Micro four Third-Camera Hype. Especialy the Panasonic GH Line of Cameras made Adapting such Lenses very Popular (and Sadly also rare and Expensive in the same turn...). But that also means, that now there is a lot of information about those Lenses, and if they will cover/ Fit an MFT-Sensor Camera (which the 2.1 Chronos basicaly is....). So, if the Lens will Produce an usable image on an Panasonic or similar Camera, it will do just the same thing on the 2.1.
For Adapting, it is actually quite a bit more Straight forward (for C- and CS- Mount Lenses at Least...) than on those Mirorless Cameras, cause you can mount directly to the Screw-Mount on the Chronos, and dont need to use an Adapter, which will be in the Way for some Lenses.
Title: Re: Let's talk LENSES!
Post by: Nikon1 on December 22, 2019, 01:07:01 AM
The 1.4 has an Smaller Sensor than the 2.1.
For Compatible Manual Lenses, especialy C-Mount just search the web like i just said about the 2.1 but look for Lenses For the BMPCC from Blackmagic (BlackMagicPocketCinemaCamera), digital Bolex and Nikon1-Cameras.
If you find Information somewhere that the Lens, you are Looking for will fit/ Cover those Cameras, it will sure Fit on the 1.4
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Hope that helps a bit with all the Confusion about Lenses with the new 2.1
Title: Re: Let's talk LENSES!
Post by: marcus on December 25, 2019, 12:05:42 AM
The 1.4 has an Smaller Sensor than the 2.1.
For Compatible Manual Lenses, especialy C-Mount just search the web like i just said about the 2.1 but look for Lenses For the BMPCC from Blackmagic (BlackMagicPocketCinemaCamera), digital Bolex and Nikon1-Cameras.
If you find Information somewhere that the Lens, you are Looking for will fit/ Cover those Cameras, it will sure Fit on the 1.4
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Hope that helps a bit with all the Confusion about Lenses with the new 2.1

Hey Nikon I sent you a DM, hope you don't mind.
Title: Re: Let's talk LENSES!
Post by: Nikon1 on December 27, 2019, 05:00:47 AM
Hey Nikon I sent you a DM, hope you don't mind.
DM Answered.
Title: Re: Let's talk LENSES!
Post by: Nikon1 on December 28, 2019, 04:51:27 AM
Hope that helps a bit with all the Confusion about Lenses with the new 2.1
I got around to do an quite detailed Post about Lenses and stuff here, For anyone interrested:
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http://forum.krontech.ca/index.php?topic=510.0