Need HPX300 expert for hire

Thanks for the feedback. I spent all day with it today and then I decided to do one simple thing. I unplugged my 30 inch monitor and stood it next to the camera, zoomed in at a person, zoomed out and stuck my face right up to the sceen and adjusted the backfocus ring slightly. To my surprise the picture got sharper. I baaaaarely touched it. So I knew I was on to something. Using the chart I adjusted backfocus a dozen times before, but this time using a large monitor and a human, staring at eyelashes and such made a difference. We started playing with that and the EX1 back to back over SDI and still the EX1 was much cleaner and sharper. I had to finish production with the EX1 but have some more to do with the HPX tonight on backfocus so I will post my results. I so hope that it is a backfocus issue.

UPDATE

I just ran to walmart and bought a 40 inch Sony Bravia 1080p monitor for tomorrows shoot. I am going to set critical focus that way and see how it goes. For now I have a gut feeling that I was trusting my backfocus too much and zooming in to focus then zooming out to frame and shoot. All the while I am thinking the unit is as focused as it can get. Maybe it was out of focus all along.
 
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Glad to hear this! When i've seen your footage the first time i've recognized that probably was a backfocus issue. I've said this because it happend to me during one work. In the output monitor everything seems good but fortunately i've my laptop with the AJ-PCD2 card reader to import immediately the footage on pc...and then i have noticed the soft picture!!! What a luck! From that day i usually check my backfocus before shooting. Some people doesn't touch it at all but you have to consider that lenses are produced in series, so one is good and another one maybe is more sensible.Consider that the climatic changes influences the metal expasion or the constriction of the ring.And another thing... i don't use anymore my bag for the 301's transport.I don't have a rigid one so sometimes i've find the lens lock slack. If you play like me much with macro, you will notice that sometimes the ring may sensible change position. At this moment i've done the test so many times that i fix backfocus in the 301's lcd. I don't use the chart but object with sharp edges. Now you have to test the camera in every situation to know the limits and the workaround to reduce the noise in the picture, not only on the tripod. I have to be honest: i don't like the EX1 picture. Maybe it's sharper but still looks a little bit "fake" for my taste. And you have to consider that the pixellation of the codec is visible when you zoom with the lens. The last suggestion: when i shoot at gain 0 1080p 25fps grain comes out as i said before on some green or brown or gray color. What i usually do is to set the detail up to -2, the coring to +4 and blur the picture with an horizontal and vertical fast blur in AE or Premiere with a 0,5 value. A little bit of fast blur make a huge difference. And you still have beautiful details in the picture.
Hope that you will have good times with this camera. Sometimes i love it, sometimes i hate it!
But for most of the time i'm really really happy with the beautiful footage that this camera can produce.

Good work!
Bests,
Roberto
 
I experimented to see what is the sharpest I can get from the camera by manipulating the focus ring AND backfocus. Here are my discoveries and photos of my mannequin as screen grabs. Please view at 100% and focus on the hair.

****************

CASE NUMBER 1

ND1
I set the camera back focus ring to the F.f arrow indicated on the lens. This I assume is the factory set backfocus. When I zoomed in and out the focus DID NOT stay.
I zoomed to Z50 which is midway.
Camera at F4
I manipulated the focus ring only

http://www.vspworldwide.com/clientfiles/download/hpx300/1.png

****************

CASE NUMBER 2 - My past month scenario

I set the camera lens wide open
ND2
Shutter 1/60
Zoomed in 100% then focused with the focus ring
Zoomed out 100% then adjusted backfocus ring - It ended up a little above the factory markings on the lens
Zoomed in to Z50

http://www.vspworldwide.com/clientfiles/download/hpx300/2.png

****************

CASE NUMBER 3

Adjusted the focus ring a little from above. MAde it a little sharper

http://www.vspworldwide.com/clientfiles/download/hpx300/3.png

****************

CASE NUMBER 4

F4
ND1
Zoomed in 100% then focused with the focus ring
Zoomed out 100% then adjusted backfocus ring - It ended up a little above the factory markings on the lens
Zoomed in to Z50

http://www.vspworldwide.com/clientfiles/download/hpx300/4.png


So from my observations my worst performance was actually using the camera following backfocus guidlines. My best performance was seen backfocusing at F4 or using the factory setting. But with the factory setting the focus did not stay when I zoomed the opposite direction. Does that mean anything? Maybe the lens is bad?
 
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I looked at your clip and its definitely not up to par. I've worked with both the 300 and 370, own a 370 and can tell you 1080 should be much crisper than what I saw. Oh BTW the clips you posted are 720....

Check the shutter control, is it "off" or "on" Off will give you more motion blur

I'm suspect some optical issue though- back focus is not perfect or something else in the optical path that is having an effect.
 
romy101 said:
****************

CASE NUMBER 1

ND1
I set the camera back focus ring to the F.f arrow indicated on the lens. This I assume is the factory set backfocus. When I zoomed in and out the focus DID NOT stay.
I zoomed to Z50 which is midway.
Camera at F4
I manipulated the focus ring only

http://www.vspworldwide.com/clientfiles/download/hpx300/1.png
Click to expand...

Number 1 looks good and right. Number 4 is a close second. The other two are not so good. Maybe your best bet is to follow your own backfocus guidelines as stated in Scenario number 1.


Jason
 
I agree number one looked the best but my problem with that is it took me having to buy a 40 inch TV and stand right in front of it to get accurate focus, framed at my final shot. What if I don't have that luxury? what if I am forced to zoom in and focus then zoom out, such as being outside the studio without a huge monitor for focus with. I am screwed.

It is pretty evident right now that I did have a focus issue all along as one, perhaps my only problem, but I don't have a solution yet as following the guidlines for setting backfocus is still yielding me a softer image when I zoom back.

Im filming at 8am EST tomorrow and this time I'll make use of the large monitor and see how nice I can get my footage to look based on this new focus tool. Afterwards I think I need to visit the backfocus issue more heavily.
 
Another thing I notice is when I turn the focus ring the image zooms in or out slightly. Is that normal?
 
Where are you located? .. you need to get this unit to a professional service center to work through the imaging issues.
I don't want to be rude, but the images you've posted are suggesting serious operator issues.

jeff
 
Hallo roomy. I think that you have to follow the suggestion to bring the camera in a support center. My backfocus is almost 3 mm away from the f.f. settings. So if i set it to the standard position i have your same result,when i zoom back i loose focus.
The first picture is the right one,so i think that the lens may have some problems. But you don't have to waste your time anymore! Bring in a tech service support and make your tests there with another 301 for comparison. I say this because it's very important to see the response of another camera of the same type in the same situation. But remember that if you want to match the EX sharpness maybe you have to play with the detail settings.

Bests,
Roberto
 
By the way, is it normal that when you set your focus in telephoto and bring the zoom back to wide if you move the focus gear -> infinite you have a slight back zoom and the image becames a little wider.
 
Thanks to all. I will send it in. I'd rather look like an amateur here and learn something, or get my problem solved than sit on my thumbs, so no offense taken Jeff. Thanks again
 
Back focus basics

Google Siemens star chart, if you don't already have a star chart. you can find images on the web which you can download and print which is good enough.
When setting back focus you always want your iris wide open, so F 1.7. Adjust lighting on star so you can shoot comfortably without over exposing or irising down to get a proper exposure.
With a standard zoom lens set the chart up on a flat surface like a wall square to camera with lens at same height as the chart at a distance of about 6 feet.
Zoom in all the way focus and zoom back to max wide. Now adjust backfocus ring for max sharpness on the star chart. Once you have done that repeat the test to make sure you've got it right. The EVF or LCD on you camera should be just fine for viewing this set up with your camera.

Don't ry to set BF with anything but a star chart. In the old days of Standard Def I used chain like fences in a pinch out in the field, but cameras back then didn't resolve much compared to what the 300 sees.
 
Oddly that is the procedure I did since I got the camera. When I zoom in , focus and zoom halfway to frame out the picture got softer. Maybe my lens has an issue. It is more apparent now that I have the 40 inch monitor in my face for focus.
 
A small correction: The Panasonic manual recommends a distance of 3m (a little under 10 feet).
"Place the flange back adjustment chart about 3m from the lens and adjust the lighting on the chart to obtain an appropriate video output level."


Mark Smith said:
Back focus basics
Google Siemens star chart, if you don't already have a star chart. you can find images on the web which you can download and print which is good enough.
When setting back focus you always want your iris wide open, so F 1.7. Adjust lighting on star so you can shoot comfortably without over exposing or irising down to get a proper exposure.
With a standard zoom lens set the chart up on a flat surface like a wall square to camera with lens at same height as the chart at a distance of about 6 feet.
Click to expand...
 
What I see going in is I backfocus as described above but when I frame the shot at mid zoom it looks a tad soft, then I fiddle with the focus to no avail. THEN I touch the backfocus ring a tad and magically it looks sharper. No matter how many times I backfocus with the chart and work at it and work at it, I always get a tad sharper image when zoomed at mid zoom and fiddle with the backfocus ring then.
 
I shoot my subjects about 10 feet away at F4 or f2.8 generally. In any event when I set the chart around 10 feet zoomed all the way out it is so hard to see the center of pattern and discern the micro adjustments. I will try again though.
 
1) your lens may have a problem tracking focus from what you describe.

2) I like my camera to star chart distance closer than what the manual recommends because it is easier to see the max sharp on the chart and it really doesn't affect the adjust. When setting BF on a wide angle zoom I put the chart even closer.

3) Can you find another lens in in your area so that you can swap yours out and eliminate that part of the system? that would tell you right away if you have a bum lens and you could go back to panasonic, get that fixed and stop tearing your hair out.

4) if you are terribly desperate for a lens I could loan you my standard zoom for a test if you want to pay for the shipping & insurance. I use my wide angle zoom about 98% or the time.
 
The sweet spot iris wise for the 300 /370 cameras is between 4-5.6 split on one end and 1.7 on the other. If you close the iris to 5 .6 or beyond there will be some diffraction effects because of the chip size & iris pupil in combination which kill resolution. All cameras suffer from this at some point, but in general the larger the chip size the higher numerically the f stop number has to be before diffraction effects kick in. Keep you iris in the range between f 4 and 1.7 with the 300 for best results. Too much light? roll in ND to but you in the right zone.
 
Thanks Mark. I am learning a lot about this camera in the process. What about my last post about the camera going out of focus when I increase the gain. Is that normal? I found a local shop that rents HPX300s . I am going to borrow a lens on Monday and see.
 
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