F-stop inquiry.

Z

Zing Crosby

New member
Hi friends! Marshall Lucky here.

I am looking to purchase a new camera here, I want something that can shoot High Def and I can carry around for a long time and also can shoot for a long time. I don't want tapes (obviously this wont be a problem with HD), I guess SD and P2 quality is the same, the only main difference is price.

I have been shooting with the DVX100 for six years and absolutely love the camera.

I was looking at the HMC150 and it looks like the fstop goes from 1.6-3.0

This can't be. I saw someone post on here that it ends on 11.

What can you tell me about this? Please help me solve this problem? What is the actual range of the f-stop on this camera?

Thank you all so very much.
 
Zing Crosby said:
I was looking at the HMC150 and it looks like the fstop goes from 1.6-3.0

What is the actual range of the f-stop on this camera?
Click to expand...


Wide End of the Zoom Range : f 1.6 - f 11.0

Long End of the Zoom Range : f 3.0 - f 11.0

...To keep a constant f stop during a zoom, determine what the f-stop is for the long end of your zoom, then set this f stop when you are at the wide end of your zoom.

For example, to have one f stop for the whole zoom range on the HMC-150, set the IRIS to f 3.0 at the widest zoom setting. Now you can zoom the entire range with one f stop.
 
I see. I wonder why they dropped 3 f-stops? The DVX100 goes to 14. I believe.

What is the main difference between this cam and it's P2 brother?

Thanks for the help so far. Thanks, Dingo, man.
 
Zing Crosby said:
I see. I wonder why they dropped 3 f-stops? The DVX100 goes to 14. I believe.
Click to expand...
They didn't drop three f-stops. They dropped 2/3 of one f-stop. The difference from f/11 to f/16 is one f-stop.

And the reason it's gone is because of diffraction; when you stop down an HD camera that far into the lens it starts scattering the light waves and results in very defocused, soft, fuzzy imagery. You really shouldn't go below f/11 on a 1/3" HD camera, and actually f/8 is a better maximum limit.

What is the main difference between this cam and it's P2 brother?
Click to expand...
HPX170 adds P2 recording, HD-SDI output, variable frame rates, standard-def recording, time-lapse, and a few other things I don't remember off the top of my head.
 
The HPX170 has several more features than the HMC150, yes. It's a more-expensive model. The HPX170 and HMC150 were introduced at the same time.
 
hmc150 will give u a much cheaper recording medium though, and barry correct me if i'm wrong but i thought the HMC cameras did timelapse, i believe i saw it in the specs pdf.
 
Barry_Green said:
They didn't drop three f-stops. They dropped 2/3 of one f-stop. The difference from f/11 to f/16 is one f-stop.

And the reason it's gone is because of diffraction; when you stop down an HD camera that far into the lens it starts scattering the light waves and results in very defocused, soft, fuzzy imagery. You really shouldn't go below f/11 on a 1/3" HD camera, and actually f/8 is a better maximum limit.
Click to expand...

I would prefer, actually, that they leave that choice up to the user.
 
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