Author Topic: Chronos 2.1 lenses  (Read 1402 times)

hydraulicpresschannel

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Chronos 2.1 lenses
« on: February 05, 2020, 09:05:41 AM »
There was already some discussion about lenses on other topic but I thought that this subject deserves it's own topic. I have been too busy to think about what lens to get and now the camera just arrived and I don't have anything suitable to film with it :D Only lens that I have is my dad's old russian 500mm mirror lens that would be probably something like 2000 mm with the crop factor taken into account. I think I have to do at least one video with the combination still :D

I think I don't want to just use some Nikon glass with always wide open hack so I have to find totally manually controllable lens and it would be probably good to be at least f 2.8

With regular cameras I use quite often prime lenses since there is enough pixels to zoom in on edit when necessary on 4k image but that's not option here so probably have to find zoom lens and it ain't going to cheap with these specs probably :D If anybody has good recommendations those are welcome.

hydraulicpresschannel

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Re: Chronos 2.1 lenses
« Reply #1 on: February 05, 2020, 09:15:01 AM »
I found one used lens for sale near. https://kamerastore.com/product/nikon-24-70mm-f2-8-g-ed-n-af-s-nikkor-7/

I think that could be probably pretty good and since it's just f 2.8 no need for any trickery to keep it open. Does anybody know whats the crop factor with Nikon lenses and the mount that comes with the camera?

Nikon1

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Re: Chronos 2.1 lenses
« Reply #2 on: February 05, 2020, 09:31:32 AM »
Hi Lauri,
The Lens you linked is Still a "G-Style" Nikon lens, you can see that by the "G" in the Lens name. That means you need to control the Apperture with the Adapter or camera and you still have the problem with the Apperture beeing Closed all the time.
Lenses Without the G in the Name from Nikon have dedicated Apperture-Control Rings. This lens has not.
I think what is intended to be used with this adapter and the camera is actually something like those primes Here (Set of Rokinon Manual Prime Lenses in Nikon mount, with apperture Rings):

https://www.ebay.de/itm/Super-lichtstarkes-walimex-pro-Vollformat-Objektiv-Set-fur-Nikon-14-24-35-50-85/174138211715?hash=item288b723d83:g:2KEAAOSwn~Bd9hfW
.
Once i got mine i could make and send you an adapter with wich you could control the Apperture, since you are in Finnland. So shipping wont be a problem for me.
.
Or (you have a 3D-Printer) just print this file in the Attachment and use this adapter, which will let you controll the apperture (This is The Adapter i use, also the one shown in the video with the "Hack"):
https://www.ebay.de/itm/Objektiv-Adapter-fr-Nikon-AI-AIS-G-Lens-to-Olympus-Panasonic-MFT-M4-3-M43-Kamera/254307153863?hash=item3b35e337c7:g:iYcAAOSwTUpdNrH0

Since nobody did give Feedback on the Functionality of the 3D-Model, you maybe need do change the Thickness to get propper Focus on infinity. If you do so, please upload the changed file for everyone else to use, that would be nice!
Also dont do to crazy stuff with this, since it has no lock, it is just clamped in the 3D-Printed Interchangeable Mount.
I can also give you Plans to build an Metal Adapter on your CNC, if you want, contact me via PM.


hydraulicpresschannel

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Re: Chronos 2.1 lenses
« Reply #3 on: February 05, 2020, 09:54:28 AM »
I sent email to that lens store and asked do they have any parts that could do the job of keeping it open. I have way too much things to do so it would be great to just solve this with out starting to design and manufacture parts :D

But the prime lens set is also pretty good option. Those would be quite fast lenses and the price isn't totally crazy.

Nikon1

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Re: Chronos 2.1 lenses
« Reply #4 on: February 05, 2020, 10:03:42 AM »
I sent email to that lens store and asked do they have any parts that could do the job of keeping it open. I have way too much things to do so it would be great to just solve this with out starting to design and manufacture parts :D

But the prime lens set is also pretty good option. Those would be quite fast lenses and the price isn't totally crazy.
Yeah, ok, i forgott, that you are also an pretty busy man...
But i also doubt that this lens Store will Have anything usefull for you. if you want THAT lens, with an easy fix for that problem, just get an older version, like the "AF" version (Non-G):
https://www.ebay.de/itm/Sigma-EX-Aspherical-24-70-mm-F-2-8-AF-D-Macro-Objektiv-fur-Nikon/293392214343?hash=item444f89e947:g:ZPkAAOSwPkheAoA4
This Version of the Lens is quite a bit older and still has an Apperture Ring, so you can control the Apperture with that.
I think, since FullHD is still a rather low resolution to todays 24 and More Megapixel, that the difference in Image Quality shouldnt be that bad... also it can be had for pretty cheap used.
.
For Primes, you could get an old 50mm Nikon Mount Lens with Apperture Ring, they cost very little. Still kinda long focal length, but fast and Cheap!
https://www.ebay.de/itm/Nikon-Nikkor-AF-50-mm-F-1-8-D-AF-Objektiv-neuwertig/164055117540?epid=100046184&hash=item2632726ee4:g:MKAAAOSwhs1eMcpz
https://www.ebay.de/itm/Nikon-Lens-Series-E-50-mm-1-1-8-Pancake-Nikon-Analog-Objektiv/143524847929?hash=item216abf6139:g:EzIAAOSwIM5eOtIm

hydraulicpresschannel

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Re: Chronos 2.1 lenses
« Reply #5 on: February 07, 2020, 12:59:06 AM »
I ended up buying Sigma 18-35mm f/1.8 lens and ordering couple of those fancy adapters that allow to control the aperture (one for color camera and one for my upcoming monochrome camera). I think I am going to buy at least one more lens so I can film with both cameras at the same time but I decide that after I have used this lens for a while.

I think I have to get lot more trigger cables since I have now already 3 cameras and it would be nice to trigger them one-by-one on some situations and from far away.

Nikon1

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Re: Chronos 2.1 lenses
« Reply #6 on: February 07, 2020, 05:44:11 AM »
I ended up buying Sigma 18-35mm f/1.8 lens and ordering couple of those fancy adapters that allow to control the aperture (one for color camera and one for my upcoming monochrome camera). I think I am going to buy at least one more lens so I can film with both cameras at the same time but I decide that after I have used this lens for a while.

I think I have to get lot more trigger cables since I have now already 3 cameras and it would be nice to trigger them one-by-one on some situations and from far away.
That is a very good idea in my opinion!That is also the exact thing, i recommended to the User marcus, when he asked me about lenses. Get whatever you think will be a good fit, use it for a while (maybe a month or two, depending on how much you use it), then decide what else to get.the 18-35 does not have a lot of Zoom and is big, fat and Heavy, also somewhat pricey, but still worth it by a lot.You would maybe want to add some Longer Tele Lens or an Ultrawide-Lens..For Lower Resolution, like 800x480px (which you will have to use anyways for the Higher Framerates...) the C-Mount Lens from the 1.4 Chronos should still be useable perfectly fine. At Higher Resolutions, it is very likely that the 12,5-75mm 1.2 C-Mount will not cover the full sensor, and you will end up with an image that has black corners.

tesla500

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Re: Chronos 2.1 lenses
« Reply #7 on: February 07, 2020, 07:17:45 PM »
Here are some lenses I highly recommend. We've been using them for taking promo videos and they work great. All of these lenses have proper built-in manual aperture controls that will work with the included Nikon-C adapter.

Nikon ED AF-S Nikkor 28-70mm 1:2.8 D
Best general purpose zoom lens we've used so far, equivalent to 14-35mm on the Chronos 1.4. Out of production but readily available on the used market.

Nikon 80-200mm f/2.8
Longer general purpose zoom. Equivalent to 40-100mm on the Chronos 1.4. If you're used to the zoom range of the Computar 12.5-75mm on the 1.4, the combination of this lens and the one above will duplicate that functionality, with a bit more zoom to boot.

For prime lenses, Rokinon makes a nice series of prime lenses and Cine lenses with manual aperture controls, any of these will suit the 2.1-HD very well. They have wider apertures than the zooms, especially in the ~35-70mm range. The pricing is very reasonable, most are in the $400-600 range

Here are more zoom lenses with f/2.8 or wider apertures. We havn't tried these ourselves, but as long as they have manual apertures they will work fine.

The 2.1-HD has a 4/3" image sensor, so the crop factor is 2:1 from full frame. You can use the Computar 12.5-75mm on the 2.1 up to about 1024x768 resolution or so (about half of full res) before it starts to vignette.

Nikon1

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Re: Chronos 2.1 lenses
« Reply #8 on: February 08, 2020, 02:24:49 AM »
Here are some lenses I highly recommend. We've been using them for taking promo videos and they work great. All of these lenses have proper built-in manual aperture controls that will work with the included Nikon-C adapter.

Nikon ED AF-S Nikkor 28-70mm 1:2.8 D
Best general purpose zoom lens we've used so far, equivalent to 14-35mm on the Chronos 1.4. Out of production but readily available on the used market.

Nikon 80-200mm f/2.8
Longer general purpose zoom. Equivalent to 40-100mm on the Chronos 1.4. If you're used to the zoom range of the Computar 12.5-75mm on the 1.4, the combination of this lens and the one above will duplicate that functionality, with a bit more zoom to boot.

For prime lenses, Rokinon makes a nice series of prime lenses and Cine lenses with manual aperture controls, any of these will suit the 2.1-HD very well. They have wider apertures than the zooms, especially in the ~35-70mm range. The pricing is very reasonable, most are in the $400-600 range

Here are more zoom lenses with f/2.8 or wider apertures. We havn't tried these ourselves, but as long as they have manual apertures they will work fine.

The 2.1-HD has a 4/3" image sensor, so the crop factor is 2:1 from full frame. You can use the Computar 12.5-75mm on the 2.1 up to about 1024x768 resolution or so (about half of full res) before it starts to vignette.
So, was the 2.1 Chronos Demo Reel shot on those?.
Because, if it was shot entirely on f/2.8, in such rather dimmly lit (For Highspeed) Scenes, i would be seriously impressed..
I did in fact expect, that this was shot on at least f/2 or even f/1.4 Lenses (For example Primes or something)!.
Cant wait, till i get mine, to do a Low-Light test, if this turns out to be the case, cause this camera should allow for some rather Low-Light shooting then!

hydraulicpresschannel

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Re: Chronos 2.1 lenses
« Reply #9 on: February 11, 2020, 12:00:43 AM »
I got the Sigma 18-35mm f/1.8 installed to the camera and it works really well. I think I am going to get some video out at latest on Sunday with the new camera.

The adapter ring with aperture control works really well. The lens is also really nice to use, focus is really smooth and even if the focus plane is quite shallow the focus peeking on the camera makes it easy to focus. I think I am going to probably get the SIGMA 50-100MM F/1.8 for second lens so I can use two cameras at the same time and having longer lens is handy for really stupid stuff  ;D

marcus

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Re: Chronos 2.1 lenses
« Reply #10 on: February 11, 2020, 01:46:29 AM »
I got the Sigma 18-35mm f/1.8 installed to the camera and it works really well. I think I am going to get some video out at latest on Sunday with the new camera.

The adapter ring with aperture control works really well. The lens is also really nice to use, focus is really smooth and even if the focus plane is quite shallow the focus peeking on the camera makes it easy to focus. I think I am going to probably get the SIGMA 50-100MM F/1.8 for second lens so I can use two cameras at the same time and having longer lens is handy for really stupid stuff  ;D

Good to know it works well! Thanks for update

Buddlich

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Re: Chronos 2.1 lenses
« Reply #11 on: February 12, 2020, 02:18:44 PM »
Since both, the 1.4 and the 2.1 have the same casing I want to tell you my "problem" here in this thread:

In the moment I use this C mount to Canon Adapter https://www.amazon.de/gp/product/B00VIVXL2E/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I'm using some quite heavy lenses on my Chronos. Having this super tiny C mount hole expanding to the Canon Adapter with this "giant" lens on it, it looks very worrying from a structural point of view.

Do you know if there are more "stable" adapters on the market... maybe some which use the for screw holes next to the lens hole??

I just know this from my Moravian Astro Camera... they have some Canon adapters that can be screwt directly to the casing ...

Or can you just prove me, that this tiny c mount thread is more than enough to hold a big 1kg lens on it's own? :D

skronstein

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Re: Chronos 2.1 lenses
« Reply #12 on: February 12, 2020, 04:17:02 PM »
Or can you just prove me, that this tiny c mount thread is more than enough to hold a big 1kg lens on it's own? :D

The Nikon 80-200mm f/2.8 is 1275g and is one of the lenses that tesla500 recommended above, so others over 1k would be ok too.

tesla500

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Re: Chronos 2.1 lenses
« Reply #13 on: February 12, 2020, 04:45:30 PM »
It may look rather weak but the C mount is quite strong. As Simon said I've used large 1kg+ lenses without issue, including dropping a camera with a ~900g F mount lens attached about 1.2m onto concrete, and the lens mount held up just fine.

Obviously, don't do anything remotely high-G with lenses like this, but for general use they will be just fine.



Nikon1

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Re: Chronos 2.1 lenses
« Reply #14 on: February 13, 2020, 01:35:18 PM »
Since both, the 1.4 and the 2.1 have the same casing I want to tell you my "problem" here in this thread:

In the moment I use this C mount to Canon Adapter https://www.amazon.de/gp/product/B00VIVXL2E/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I'm using some quite heavy lenses on my Chronos. Having this super tiny C mount hole expanding to the Canon Adapter with this "giant" lens on it, it looks very worrying from a structural point of view.

Do you know if there are more "stable" adapters on the market... maybe some which use the for screw holes next to the lens hole??

I just know this from my Moravian Astro Camera... they have some Canon adapters that can be screwt directly to the casing ...

Or can you just prove me, that this tiny c mount thread is more than enough to hold a big 1kg lens on it's own? :D
So, third try then...
I tried to Upload an image of an Heavy C-Mount Lens, but since i now wrote an Lenghty Post twice, and ended up with an error-Page when trying to preview (with my text all gone...), i will just use Links now...https://www.engineeringtoolbox.com/metric-bolts-minimum-ultimate-tensile-proof-loads-d_2026.html.Here is an List with proof Load Rating of different Bolt Sizes. C-Mount is Basically just an 25,4mm (1") 32TPI Fine Screw Thread, so, even given the Fact, that it is Hollow on the inside, it should still be able to hold a lot of weight (easily 50~100kg or even way more according to this link). This is for Steel Bolts though, smaller/ Cheaper lenses and adapters are Aluminum, more Premium Ones or Very big/ Heavy ones are made from Stainless Steel..I had an 16-160mm 1.6 Tarcus Brand C-Mount Lens once, dont have it anymore, this was a Very heavy and big lens. Propably over 2kg, and never had any problems with the C-Mount.Since i can somehow not post the image right now because of error pages, here is a link to the Fattest and Heaviest vintage C-Mount Lenses i could find for the Moment (Most of them Wont cover the Chronos 2.1 Sensor, keep that in mind!):.This one Has 5lbs Weight!:
https://www.ebay.de/itm/SUPER-16-ANGENIEUX-ZOOM-SUPERSPEED-1-9-15-150MM-LENS-C-MOUNT-BMPCC-MOVIE-CAMERA/291640944665?hash=item43e727a819:g:0C0AAOSwHnFV5eov.https://www.ebay.de/itm/Angenieux-10-150mm-T-2-3-C-mount-S16-Cooke-BMPC-Red-Alexa/184071216674?hash=item2adb7fde22:g:UrIAAOSwS1Jd6RPC.https://www.ebay.de/itm/Schneider-Kreuznach-Tele-Variogon-1-4-80-240mm-C-Mount-w-hood-and-case/264631424263?hash=item3d9d431507:g:EQwAAOSwz5peQz91...I can just agree, what tesla500 said, dont do way too crazy Stuff including high-G and Physical Shock with it, and you should be fine, mounting about anything to it you would propably ever want to mount.
However, most bigger and heavier Lenses Do come with an Tripod Mount built in, if it has one, use it. Also, if your Lens is heavier than your Camera, Handle, Hold, Lift, and Mount the Whole Rig by the Lens. This is just an general Reccomendation for any camera System, not just for C-Mount but also applies here...Yet anothe Point i want to make:
https://en.wikipedia.org/wiki/Flange_focal_distance.Look at this list of Lens mounts, C-Mount is now almost 100 Years old! and Thats for a reason. It did stand the Test of time, and has proofen it self. This is the Oldest Lensmount, for which new Lenses Are Produced up to this day, and no end in sight. Again, As tesla500 Said, it might look not like much and too small, but it is quite the serious Mount!.I am also pretty Happy, that they went with this combination of the CS-Mount and the four-Hole Box-Mount, because, unless about any other Camera of this kind, it allows you to mount about every lens ever made, including almost any Mirrorless Lenses known today (Electronic Focus-By-wire Style Lenses are a problem, but i mean just beeing able to physicaly mount the Lens itself while maintaining propper Flange Distance is quite a big thing!)...If you still feel the Need to mount the Lens more sturdily, search the internet for those Rod-Type Supports they use in Professional Cinema. Supports for different size Cameras and Lenses Are Available, if you search a bit, also Rods at different Lenght. Even More Stable/ Serious Solution would be to use an Adapter which uses the four M4-Hole-Mount on the Front of the Chronos Camera Body.
 I and a few other People on the Forum can Make one, if you still feel the need, or just find sombody to make one for you, for example a local Machining Shop. Its still just a Pice of Metal at the end of the Day.
EVEN MORE Sturdy would be to just Modify the Lens and get it Rehoused or get the Mount itself changed to just mount directly to the four Holes on the Chronos, this way you dont have anything between the Lens itself and the Camera.If that is still not enough, also support it by Some Kind of Cage (Highly Required, if you for some Reason end up needing to use big and/ or heavy Lenses in high-G /Vibration/ Physical Shock situations)
...
Hope this, as requested, was enough to proof to you that C-Mount will be able to handle Lenses of 1kg and beyond just fine. Maybe dont use your Camera Rig as An Hammer or as a Mounting Point for your Heavy Lifting Equipment, but everything else should be fine  :)