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Old February 21st, 2017, 02:09 PM   #16
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Re: Using B4 lenses?

"Optical Resolution v Video resolution"

Yep I'm curious about how that works, it seems the lens being the first thing in line would count the most, but if the camera shoots 4k it may make it look retro cool or something.

I tested my old FUJI 14x SD ENG lens today, can answer a couple of questions-

Quote:
Originally Posted by George Odell View Post
1) this camera can adjust its scan electronically so will it cover the full frame with no vignetting at WA?

2) how bad does it look and am I way better off getting an B4 HD... will it make that much difference?

To those using this... which adapter are you using?

Thanks!
1) Yes. I set the VSM at 43% and there is no vignetting. Also I've read that people use the doubler x2 when using these lenses, but on this camera at 43% you don't have to use it so the image is clearer, and you can use it to get even closer and lose some more light.

2) I shot a little bit today on it, I'll post a sample clip tonight or tomorrow. It seems like an HD version would make a difference, but I thought those things were crazy expensive. My plan was just to use it in good light if I need long range zoom at a game. .

3) The adapter I'm using is a simple dumb adapter that a guy included when I bought the lens on ebay, looks like maybe $40 variety.
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Old February 22nd, 2017, 07:19 AM   #17
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Re: Using B4 lenses?

Great if you can post some clips. I'm very interested in seeing the results.

BTW: Can you post the full model # off your lens, please?

As to using the X2... for cameras that do not have a way of adjusting the scan size like the LS300 the doubler is needed to fill up the frame. Appears, from your tests, using it is not needed. Just as well.

I also expect (correct me if I'm wrong) once you come off that full 4K frame scan to adjust for any lens you are no longer shooting at true 4K (4096 x 2160 pixel) resolution. You have cropped in from the full size of the 4K sensor. It may still output something called "4K" but not at the original resolution of the full frame.
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Last edited by George Odell; February 22nd, 2017 at 08:17 AM.
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Old February 22nd, 2017, 10:39 AM   #18
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Re: Using B4 lenses?

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Originally Posted by Steve Rosen View Post
William, I just noticed your post asking about back focus, sorry I missed it before..

All cine zooms have "adjustable" back focus, but it's not a rotating collar as on some adapters. You remove the rear collar (with screws) and add or subtract very thin shims made specially for the particular lens. It's a job for a lens technician with a jig for testing focus... For the layman, it's trial and error, which is mostly error...

As an experiment I attempted it on my Canon 12-120 after I added an OLPF to one of my Pocket Cameras... I was very careful to make note of the several shims that were already in place, then added and subtracted shims that came with the lens when I bought it with my first ACL in 1974.

I was never able to reach a satisfactory combination of shims. I either had no infinity focus, or I had infinity focus before the barrel reached the stop...

BTW, that particular Canon lens was promoted as having "flourite elements" back then, and sometimes temperature variations would change its infinity setting. But I'm aware of that, and it wasn't the cause of my problem.
\
Thanks for the answer. My experience has been exclusively with rotating back focus collar lenses, I remember just one zoom lens that absolutely refused to back focus properly on a specific Ikegami tube camera when switched with the other model of Ikegami camera's original lens. The original lens adjusted fine on the other camera when switched. I think we were switching them due to a bad tube registration alignment error that cropped up on one camera and we wanted the better zoom lens on the good camera. This was before automatic registration could be done. Anyway it didn't work and I ended up drawing a registration chart (the kit chart was left behind) and manually registering the camera.

Shims make sense to me, but wow. That's a job I am glad I missed.
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Old February 22nd, 2017, 11:18 AM   #19
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Re: Using B4 lenses?

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Originally Posted by Jay P. Kaley View Post
Thanks William, on that same line- When you shoot with an old SD ENG lens on a modern "HD" setting what is the actual resolution? Is it still 1080? Is it considered 'upscaled' to 1080, but it's it's not really 1080?
A photo of one hundred same color marbles arranged neatly next to each other on a table. You can see and count them all if the photo is composed right (example: the lens is wide enough) and the resolution of photo media (film or digital) and the lens is high enough not to blur the edges between the touching marbles. A higher resolution in the media or lens will not change the subject of the photo. You still clearly have 100 marbles. Now let's say that the lens can't clearly resolve the marbles, you might be able to tell it's a lot of marbles but an accurate count is impossible. That's a pretty bad lens but all we have available, like an old flip phone camera. A better camera resolution will not get us an accurate count of the marbles. The lens can't do it. A better camera might get us better color and luminance captures but that's it.

So using a working SD lens in HD that doesn't resolve to HD but is sharp to the best of it's abilities will give you a look that might work well dramatically to enhance an atmosphere in a scene. Like I said before, some optical lens filters do similar functions, for example skin tone softening filters target the red spectrum to blur blemishes and wrinkles. Most decent lenses are rated above the capture resolution of the camera they are designed for. Sometimes they are just below.

What passes for an attractive look is highly subjective. Resolution, DOF, color accuracy and frame rate all play into it. Sports, news and some documentaries like high details, wide DOF, higher frame rates and accurate color. Drama goes all over the place, lower details, shallow DOF, odd color balances, nothing higher than 24f, artificially added grain, etc. So what do you expect from an SD lens on a HD camera? It might work for sports, it might work for documentaries, it might work for drama. If you are trying to duplicate a decent HD video zoom lens for a client, it might work, but I wouldn't set my hopes too high. Better to be surprised than depend on it.
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Old February 22nd, 2017, 11:46 AM   #20
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Re: Using B4 lenses?

"So what do you expect from an SD lens on a HD camera? It might work for sports, it might work for documentaries, it might work for drama. If you are trying to duplicate a decent HD video zoom lens for a client, it might work, but I wouldn't set my hopes too high. Better to be surprised than depend on it."

That's well said, and really how I am approaching it, just to see if I'd be surprised, not counting on it at all. The B4 lens I bought was about $300, just an experiment thing while I was researching lenses.


Quote:
Originally Posted by George Odell View Post
Great if you can post some clips. I'm very interested in seeing the results.
BTW: Can you post the full model # off your lens, please?
I shot some standard dog running around footage and birds, zooming in and out, I'll post it here in a bit.

The model # I bought is FUJI A14x9BERM. It's 14x B4, 9mmm-126mm 1.7. The guy included the dumb adapter with it, I don't know the model but it works well no play at all. I did remove that little bracket, it rubbed the ND filter and wasn't long enough to do anything anyway.



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Old February 22nd, 2017, 12:33 PM   #21
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Re: Using B4 lenses?

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Originally Posted by Jay P. Kaley View Post
The model # I bought is FUJI A14x9BERM. It's 14x B4, 9mmm-126mm 1.7.
That looks to be an older 2/3" tube camera lens from the late 1980's. I had one on my Sony BVP-3. Frankly, that lens was bad by SD chip camera standards let alone using it on an HD camera. It just did not hold up.

I'm thinking more along the lines of a later version internal focus type lens made for the CDD's specifically, which had a fixed optical block... no adjustment of individual pickup tube focus position.

Still, an HD version would probably blow the doors off even a lens such as that.
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Old February 22nd, 2017, 01:02 PM   #22
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Re: Using B4 lenses?

That makes sense for couple hundred bucks, I didn't know it was that old or anything about it, was looking for something old and greasy like I used in the 90s, but maybe I overpaid haha. I'll call it establishing the low base line. :) For sure your more current lens should look better, or certainly an HD one, but be expensive.

Here's a couple pics on camera with adapter, the blue battery pack powers the servo.





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Old February 22nd, 2017, 03:31 PM   #23
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Re: Using B4 lenses?

Jay, as a word of caution.. B4 mounts were designed to be strong enough that you could use the lens as a handle (which, as an old film guy I could never get used to) - but typically MFT mounts are not that strong.

The LS300, despite what some have said, has a pretty well-made inner structure, but with a lens that long and heavy I'd want some sort of support.
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Old February 22nd, 2017, 06:37 PM   #24
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Re: Using B4 lenses?

Yep thanks for the heads up Steve, I've worried about that too, have ordered one of those 'y' lens supports in case I use this lens, but it will most likely end up a paperweight when I get used to what I'm doing on the new form. It hasn't been on the camera much, but I have been aware of not wrenching it around. And that mount does feel real solid, I haven't felt any play at all in it.
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Old February 22nd, 2017, 06:41 PM   #25
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Re: Using B4 lenses?

Here's some video I shot with the old Fuji B4, in cinema and a little J-log. I don't know what i'm doing on color correction yet, I just clicked FCP's "balance the color" button and some a contrast filter on a few shots.

The VSM was at 43% for no vignetting, and you can make regular use of the doubler, really cuts down the light I gained up when I used it.


I think it looks kinda funky, might be good for a retro look sometime.
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Old February 23rd, 2017, 06:56 AM   #26
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Re: Using B4 lenses?

Quote:
Originally Posted by Jay P. Kaley View Post
Yep thanks for the heads up Steve, I've worried about that too, have ordered one of those 'y' lens supports in case I use this lens, but it will most likely end up a paperweight when I get used to what I'm doing on the new form. It hasn't been on the camera much, but I have been aware of not wrenching it around. And that mount does feel real solid, I haven't felt any play at all in it.
I believe the LS-300 manual specifies 800 grams as the max unsupported weight on the lens mount.
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Old February 23rd, 2017, 08:53 AM   #27
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Re: Using B4 lenses?

Well that's not ideal, that old Fuji lens is probably twice that. I did consider it, didn't see it in the manual, but haven't read it all. My thinking was it's made for adapters and heavier EF lenses and the mount seems strong. Hope it's okay, there wan't any play in it but a lens I ordered should arrive today, I'll mount them and take a look, thanks again for the heads up.


I wouldn't use that old Fuji for anything other than a retro look if needed, but I'd be curious to see what a more modern HD version would look like, although in the 4-5k range don't know it would be worth the surprise.
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Old February 23rd, 2017, 11:15 AM   #28
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Re: Using B4 lenses?

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Originally Posted by Jay P. Kaley View Post
I think it looks kinda funky, might be good for a retro look sometime.
To be honest, I think that looks pretty good all things considered. Better than I would have anticipated.
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Old February 23rd, 2017, 12:33 PM   #29
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Re: Using B4 lenses?

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Originally Posted by Jay P. Kaley View Post
That makes sense for couple hundred bucks, I didn't know it was that old or anything about it, was looking for something old and greasy like I used in the 90s, but maybe I overpaid haha. I'll call it establishing the low base line. :)
I was not suggesting you made a mistake. In fact, I paid $4500 back in 1986 for that exact same lens, new. It was state of the art then.

I also think it does not look all that bad. That said, perhaps you can do another test at some point that might show us more. If you have a city nearby or at least a decent brick building, these always work well for testing image detail from corner to corner. Try to shoot square on and fill the frame. Even lighting all over. Locked off shot with different focal lengths (stop and hold the shot for 5 seconds, then move to another FL) so we can see if focus holds throughout the zoom range. Keep the F stop around F4 to F5 and forget that 2X extender. It's worthless. Too much light loss and it shades in the corners to be of any real use.

$300 for what was a $4500 lens is still a deal.
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Old February 23rd, 2017, 01:28 PM   #30
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Re: Using B4 lenses?

Not at all, I appreciate the info, I figured it was an old CCD lens but kinda cool it's an old tube deal that's still working. I might try the brick test, I could tell it was worse on the edges at full wide and looked better as it zoomed, whatever that means, figured something about being made for the 2/3" sensor.

And "funky" is a positive take, it looked better than I thought it would too, will take it to soccer practice in a few weeks and see what humans look like running around, it might make for a change of pace or promo type thing.

If you shoot some on the nicer ENG lens you have I'd be curious what it looks like too. I haven't used 'DSLR' type zooms yet, still don't know how they match the function of that old school ENG type servo, but i also don't need it often either, just such an ingrained habit to punch in close.
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