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Old June 10th, 2014, 12:32 PM   #1
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HM650: bum or expectations too high?

Even when I was shooting 35Mbps, some shooters and editors said the footage looked noticeably soft. One took footage into Adobe Premiere and said he used "sharpen" and had the sharpen value up to 50. He said normally, he can't get the slider past 10 before a picture gets pretty ugly.

I just did a test at 50Mbps and found adjusting the Detail parameter from 1 to 10 and back seemed to make no difference. The blacks crawl a bit and lack detail.

I'm trying to ascertain if there's something wrong with the camera (in addition to the problem with the Detail parameter) or if that's as good as it gets with the HM650.

If you have time or interest, here's a link to test footage.
https://www.dropbox.com/s/vylj4e4cq3...dHM650Test.MOV

I suggest downloading rather than viewing via dropbox.

Thanks,

Ty Ford
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Old June 10th, 2014, 09:04 PM   #2
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Re: HM650: bum or expectations too high?

Hi Ty,

I heard you mention in the video that you were at f22 on the lens...correct? If so, the problem you are experiencing is iris defraction(iris closed too much). On a camera with 1/3" chips, you should avoid stopping down below f5.6 as the lens will start to go soft. It's an optical issue, and No amount of detail enhancement will make the picture sharp.

Use the ND filters,gain and shutter speed to control your exposure, and keep the iris between open and f5.6, you'll see the difference. When the lens is providing a sharp image to the sensors, the detail enhancement will be quite easy to see.

Good luck!

Scott Berrington
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Old June 10th, 2014, 10:32 PM   #3
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Re: HM650: bum or expectations too high?

Scott's right; the biggest thing I've found that ruins the image quality is closing down the iris too much. f5.6 is optimal (I have my close limit set to f8). At F5.6, pretty much everything is in focus and the image is nice and sharp.

The HM600/650 might not be as sharp as a camera with a larger sensor, but it holds up pretty well in my opinion.
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Old June 11th, 2014, 03:11 PM   #4
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Re: HM650: bum or expectations too high?

Thanks Guys,

I'll try that and get back to you.

Regards,

Ty Ford

Edit: So, you're saying 5.6 or below? Anything above 5.6 is decreasing the sharpness? If pushed to it. How far up in f-stop will you go?

My camera/lens goes down to 1.6. Is there a downside as I go below 5.6?

Thanks and I really appreciate your schooling.

Last edited by Ty Ford; June 11th, 2014 at 03:40 PM. Reason: more content
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Old June 11th, 2014, 04:52 PM   #5
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Re: HM650: bum or expectations too high?

Quote:
Originally Posted by Ty Ford View Post
Thanks Guys,

I'll try that and get back to you.

Regards,

Ty Ford

Edit: So, you're saying 5.6 or below? Anything above 5.6 is decreasing the sharpness? If pushed to it. How far up in f-stop will you go?

My camera/lens goes down to 1.6. Is there a downside as I go below 5.6?

Thanks and I really appreciate your schooling.
I usually push to f8 if I have to. And below f5.6 is fine. I've read that a lot of lenses will get a bit softer wide open, but I haven't noticed it on the HM600.
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Old June 12th, 2014, 07:51 PM   #6
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Re: HM650: bum or expectations too high?

Better, I'm happy to say.

Here's a clip I shot in the studio shot at 5.6 and you can see some detail increase.

https://www.dropbox.com/s/1ttpbvh32t...HM650Test2.MOV

Don't try to play it from dropbox, download it first.

I think it may be safe to pop the detail level up in general.

Still some noise in the blacks, but I was expecting that.

Thanks for your help and please toss in any other comments you have.

Regards,

Ty Ford
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Old June 12th, 2014, 08:31 PM   #7
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Re: HM650: bum or expectations too high?

Quote:
Originally Posted by Ty Ford View Post
Better, I'm happy to say.

Here's a clip I shot in the studio shot at 5.6 and you can see some detail increase.

https://www.dropbox.com/s/1ttpbvh32t...HM650Test2.MOV

Don't try to play it from dropbox, download it first.

I think it may be safe to pop the detail level up in general.

Still some noise in the blacks, but I was expecting that.

Thanks for your help and please toss in any other comments you have.

Regards,

Ty Ford
Glad it's looking better.

If you haven't already, this is worth reading:
https://tech.ebu.ch/docs/tech/tech3335_s08.pdf

It outlines some recommended settings for the HM600/650 (including info on the detail setting).

I've also read that the camera uses some detail enhancement even when detail is set to the lowest value. The report recommends -4, which is what I've always used.

As for your comment about some noise in the blacks, I've noticed that too, even at 0dB. I think it's normal for a small 1/3" chip camera.
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Old June 12th, 2014, 10:28 PM   #8
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Re: HM650: bum or expectations too high?

Jody,

Thanks for that. I had seen it, but only recently knew enough to begin understanding what all of that info actually means. I've been an audio guy and I didn't start shooting until 2007. That was with a Canon XL2. Nice camera within its limitations, but I wanted to step up to HD and the 650 looked like a very good way to go. The vendor has some NAB-opened specials from last year's show that saved me over $1000.

Again, thanks so much for your help. It really means a lot.

Regards,

Ty
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Old June 12th, 2014, 11:12 PM   #9
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Re: HM650: bum or expectations too high?

Not a problem! Glad to help. I'm relatively new to this too, I've only been doing it for a few years. I've basically learnt everything I know from this forum and from teaching myself, so it's nice to be able to give some information back.
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