HPX250: HPX250 Review by Adam Wilt

Very thorough review. Mr. Wilt describes the auto-focus hunting issue but does not see it as problematic. I don't think I agree with that but at least he also experienced the problem.
 
After having worked with my 250 for around 1 month now I must say its not an issue anymore for me. Its good to know the limits and work around those.
The lens is not parfocal in macro mode...I wonder which lens is and how much it costs...whip zooms show that the electronics that correct focus, are too slow...I dont do whip zooms.
 
I see it as "there's no such thing as a free lunch." The lens is super nice and has an incredible range, along with macro mode. Something has to give somewhere, and if that somewhere is a slow/hunting autofocus, then I think the trade is spot on.
 
Well, yeah, basically that's it. The lens is massive and I would imagine flinging that much glass around is going to impact AF performance. On top of that, these cams are way sharper than their prior cameras, so the difference between "in focus" and "out of focus" means that a lot higher precision is required. Autofocus on a standard-def 10x lens like the DVX is probably trivial as compared to autofocus on a huge-glass 22x lens on chips that are 4x sharper.

I think it is probably a case of that they could have made it autofocus faster if it had a smaller 10x lens, or a softer picture, but they had to figure which was more important to the target audience: massive zoom range, or superb autofocus? If I had to choose one or the other, I know which I would go with.

I think it's also interesting that on the original DVX100, it didn't even have autofocus AT ALL when in 24p or 30p. They added it later, but even then they didn't call it autofocus, they called it "focus assist." Maybe they should have called this "focus assist" and then people would have more in-line expectations?

I guess where we are at is if someone wants brilliant autofocus they can get that with the smaller-lens, bigger-pixel hmc150 or Hpx170. And if they don't prioritize autofocus that highly, they can get the bigger zoom and higher res of the ac130/160 or hpx250.

I know we all want everything all in one, but it looks like once again we have to prioritize.
 
I posted this over on Adam's site but never got a response so I'll post it here. Perhaps someone who has experience with both the HPX170 and HPX250 can comment.

Adam, thanks for the very thorough review. I shoot a lot of nature material and use the HPX170. I like the HPX170 but I feel it is lacking in detail/resolution. Do you think the HPX250 is a vast improvement in image quality over the HPX170? I tried to find some raw HPX250 clips so I could compare, but have been unsuccessful. My main product is for DVD, BR and HD on the web.

Also, this is a big investment for me and I am somewhat worried about rolling shutter "jellowcam". I have never owned a CMOS camera before. You can see the type material I shoot at http://vimeo.com/channels/3523
 
For a recent job I rented an hpx250 from Don at Cleveland Camera. It's a nice way to get a thorough test drive.
 
And how did your job go? Were you impressed with the 250? Did you end up purchasing one after using it on this job?
 
Mark Williams said:
I posted this over on Adam's site but never got a response so I'll post it here. Perhaps someone who has experience with both the HPX170 and HPX250 can comment.

I like the HPX170 but I feel it is lacking in detail/resolution. Do you think the HPX250 is a vast improvement in image quality over the HPX170?

Also, this is a big investment for me and I am somewhat worried about rolling shutter "jellowcam". I have never owned a CMOS camera before. You can see the type material I shoot at http://vimeo.com/channels/3523
Click to expand...

I'm not Adam--but I know him! The 250 resolves more detail than our HPX2700, much less an HPX170. The difference is most apparent when viewing a wide shot, the 170 just can't resolve the kind of detail that full raster chips can. The 250 is also quieter, allows knee control in Cine gammas and actually records what it shoots. A 170 CCD set is only 540 lines, pixel shifted, and even if it could derive a true full raster image from it's sensors, the DVCPRO HD codec does a 3/4 sub-sample of horizontal resolution. 250 full raster sensors plus AVC-Intra 100 means every pixel of information is recorded and with 4X color bit depth of DVCPRO HD.

The CMOS skewing on a long lens with fast action could be more of an issue and would require real world testing for your applications.
 
Gary Huff said:
And how did your job go? Were you impressed with the 250? Did you end up purchasing one after using it on this job?
Click to expand...
It went very well. I own an hmc150 and needed broadcast specs and wanted to give it a test drive. Other than the boost in sharpness, it seemed to resolve skin tones with more subtle gradations...nice. Haven't purchased yet...still on the fence about small vs big chip, and the endless waiting to see what's next around the corner,
 
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