HMC150's close-up focus problem

M

MorleyUK

Member
I've had my HMC150 for a year now and one of the things i first noticed when shooting with it was that when i'm focussing on a close object (about a foot away) whilst zoomed in quite a bit (Z70 and closer) the object, appears to move away from me, ever so slightly, as i pull the focus from near to far, and vice-versa. It didn't bother me at first by I'm noticing it more as i use the camera more and more (gradually phasing out my use of my DVX100B's) and it's starting to bug me. I was filming a slow glide over some flowers the other day, with the focus on auto, and as the camera focused on various flowers at different distances from the lens, the whole bunch of flowers appeared to pulsate in and out! I've just tried this with one of my DVX's and the focus is completely clean and how i would expect it to be.

I've just compared the two camera's in manual focus mode and there is definitely a difference in the way the two cameras handle this situation. Having been using cameras, of some form or another, for the last 20 years i'm sure that something is wrong here.

Is this something that other people have noticed with the camera, or have i picked up a dud?

Thanks

Chris.
 
Some lenses simply "breath" while focusing... Using older Nikons lenses (amazing lenses!) I really know how it can be... Not much you really can do about it as far as I know and understand.
 
Just done some research and it seems that nowadays it's an issue with the cheaper lenses. What does this say about the HMC150 lens? Why would panasonic change from a perfectly good lens on the DVX to a poorer lens on the HMC150? I'm currently on the verge of letting my two DVX's go in order to get a second HMC150. Was I just very lucky/unlucky in choosing such a great camera in the first place (DVX100B) that nothing in the same price range will ever compare with?

Feels like i'm trading down!
 
I've really changed my focusing style with the 150 - I haven't had the time to test it, but I get a feeling the focus shifts at the far end of the zoom. For years I've focused by zooming in all the way, but now I do more like a half zoom and hit the focus assist or the 1:1 switch on my monitor. I just see some funkiness with the focus at the far end of the zoom. It may be just fine, but it's so completely different than any other camera I've used, from the DVX to SRLs that it makes me cautious.

I do need to take the time to test it - it may just be something different about the optics. But for now, I don't rely on a full zoom for focusing.

Morley, I don't feel the 150 is a trade-down; there was something special about the DVX for many. It was a breakthrough camera, and the only experience I've had close to it was when I got my DSLR technique going. We don't get beatlemania very often in life, and the DVX was definitely that level of "wow". But I'm quite happy to do greenscreen work with the 150 - ever try to key a DVX shot?
 
Thanks Michael and Admir for your replies.

Michael, i haven't noticed the 'funkiness' that you've mentioned. I'll check that myself. I normally zoom in to focus too. I guess that the more you zoom back out after focusing, the less the inaccuracy of the initial focus matters. I can see where it would be a problem though.

I can see masses of plus points about the HMC compared to the DVX but they are mainly due to the format that the footage comes out as - there's much more 'information' to play around with in post - but the actual camera (optics, body) makes me sad to let the DVX's go. I even like the way that the auto focus on the DVX when shooting progressive is really slow - If I pan slowly from one side of a crowded room to another, at head height and on max zoom, the DVX would gently shift it's focus, near and far, from one face to another and look really good and natural. If i try the same thing with my HMC, or any other camera, the focus shifts are too quick, add the lens beathing with the HMC... that's one of my trademark wedding shots gone!

Anyway i can make my DVX shoot HD and native 16:9??? :smile:
 
There is a term for it but it escapes me. It is generally referred to as a cheap thing, and while it no way exudes a sense of high value, it sometimes is something that occurs when you are trying to build a lens with a level of optical quality, focal range, and focal distance, that just requires you to live with it as a compromise for all those other things. Something has got to give, the fix is likely adding 1 or more glass element, which would likely degrade optical quality and increase production costs.

And I want the DVX100 to live on forever, I love the form-factor and price-point. If they could make it modular so you could replace pieces to upgrade it as needed or as available, I would still have my DVX100.
 
I find the HMC's lens to be really good for the price actually. Breathing isn't anything new or "wrong" with the camera, it's just the way it is. Just like the codec, the DVCPROHD codec is better, but with that said, there's nothing wrong with the AVCHD codec, it does the job any way =).

Also, try to think about it next time you watch a movie, you will see that many times lens breathing occurs and sometimes it's really visible when they do fast focus transfers. I don't need to mention that the lenses they use probably costs more than my entire camera setup, and even at that price range they create focus breathing sometimes...
 
Last edited:
Yeah, it's easy to forget what happened when you tried to push DVX footage very far in post. The 150 has its issues - it's got some weirdness in the compression if you don't find a way to light and expose for a lot of brightness info. That said, my first few major HMC shoots did involve greenscreen, and that's where the footage can fall apart fairly quickly. It's really a nice looking camera under normal use.

I just really, really need something like the (cough cough) Scarlet to become an affordable reality - they're still talking this fall. Am I like Charlie Brown with Lucy's football or what??
 
You must log in or register to reply here.
Back
Top