Need HPX300 expert for hire

I got the Putora test chart in today and performed a backfocus according to the instructions provided with the chart, which is the same instructions provided in the HPX300 manual. The chart has circles that get sharp when you are in focus and wash out when not.

I was fully focused zoomed in and fully focused zoomed out. Performed it again and again. When I was zoomed half way in we lost focus. I know conclusively because when i fiddle with the macro focus a tad the circles became sharp. When I put it back to the snapped in default place, we are out of focus as the sharpness circles wash out and disappear against the grey background of the chart.

I did not bring it back to my own infinity backfocus experiment yet because I had a long day of studio shoots and it was late. Tomorrow I will try it. The Putora chart makes it easier to gauge at all zoom ranges because the circles have a most sharp place and you can see where the sharpest spot is by just wiggling the focus to and fro. When I am getting sharper readings at different focal lengths than my zoomed in focus, all by wiggling the macro focus a tad, then I know I am not holding focus throughout those focal lengths.

Thursday I may be able to get another HPX300 to test with my same chart. I will backfocus with the other HPX300 and see if theirs hold focus.
 
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hotchkiss said:
I've followed this thread with great interest, as I've had ongoing issues with back focus on my 300 as well. It caused trouble for me with a show I was shooting for Lifetime- a big bummer... Can you say "comp-ed day rate". Ouch. The massive DOF and my middle aged eyes makes it more of a challenge to find focus with the 300 compared to a 2/3 inch cam.

Romy, I'm happy that you've solved the issue- I was feeling your pain. ;-)

My issue has been the same, losing focus on mid focal length shots. I re-set it over and over, and while it's much improved, I'm still leery and find myself checking focus for these kinds of shots- especially interviews. I'm going to order the Purtoa chart for sure.

Are you still pretty confident that incorporating the infinity mark in your method has solved the issue?

Just curious- does anyone else incorporate the use of the infinity mark to set BF?

This method is making some sense to me. Once I get the Purtoa chart, I'm going to try it as well.

Any thoughts?
Click to expand...

Alright, I'm jumping in to this as well. I to have had some issues with my focus. I to have middle aged eyes...lol When I focus on a subject, it looks crisp and in focus in the viewfinder and on the LCD. I have shot alot of B-Roll with this camera and it all looks great.

My problem has been interviews. I light them well an keep the iris in 2.8 - 4 range. I focus and it pull out and it looks good in the VF and LCD. I watch it later in FCP and it looks just a smig or more off. I do interviews in news on a daily basis with the 2000, in HD and do not have this problem. I have taken it to a studio and ajusted the backfocus, which seemed to be on. I think it is some kind of mid range thing. This has happened on three different shoots.

I have been told to invest in a monitor, which is something I am more than willing to do as a do more production. But I should be able to pull focus with just the camera itself. It's bothered me cause I can't seem to put my finger in it yet.

example:

GOOD in focus: http://vimeo.com/18603685

The BAD (Interview) Focus: http://vimeo.com/17749898


I think it's something in the mid range, as I focus on the eyes and pull out.....MID WAY and seems to come across like this. I will get one of the charts and give it a try. I get nervous now as I am being called to do more interviews..... which I think will be simple...Right? I'll try anything.

Thanks
 
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Here is my conclusive evidence using the Plutora chart. I had to go to my office and do this tonight cause it was bothering me. Look at these frame grabs at 100% only and focus on the center circles at Z50.

Step1:
I backfocused at ND2, 1080, 30p, by zooming in, focusing, zooming out, messing with the flange back, zooming in, back out etc then tightening the screw.

Final shots
ND1, F2.8, 1080, 30p

============

Here is zoomed in and focused

http://www.vspworldwide.com/clientfiles/download/hpx300/18.png

Here is zoomed back out only

http://www.vspworldwide.com/clientfiles/download/hpx300/19.png

Here is zoomed to Z50 (LOOK AT THE MIDDLE CIRCLE)

http://www.vspworldwide.com/clientfiles/download/hpx300/20.png

Here is messing with the flange back with no other touches to camera - COMPARE MIDDLE CIRCLE TO LAST SHOT

http://www.vspworldwide.com/clientfiles/download/hpx300/21.png


====================

Step2:
I backfocused at ND2, 1080, 30p, by zooming out and setting focus to infinity, messing with the flange back, zooming in, back out etc then tightening the screw.

Final shots
ND1, F2.8, 1080, 30p

============

Here is zoomed in and focused

http://www.vspworldwide.com/clientfiles/download/hpx300/22.png

Here is zoomed back out only

http://www.vspworldwide.com/clientfiles/download/hpx300/23.png

Here is zoomed to Z50 (LOOK AT THE MIDDLE CIRCLE)

http://www.vspworldwide.com/clientfiles/download/hpx300/24.png

Here is messing with the flange back with no other touches to camera - COMPARE MIDDLE CIRCLE TO LAST SHOT

http://www.vspworldwide.com/clientfiles/download/hpx300/25.png


=============

Conclusion. My prior post that my problem was fixed was false. I think my eyes were just playing tricks on me and maybe I was hoping too much. No matter how I backfocus I still have issues in mid range focus. When I shoot green screen I zoom in, focus and frame at about Z50. Obviously this will give me unfocused shots, so for now I am resorting to focusing at my final frame with the flange back and looking at my 40 inch monitor up close. That is not a solution but gets me by till I find out what is wrong and how to fix it.
 
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JSPEV said:
I think it's something in the mid range, as I focus on the eyes and pull out.....MID WAY and seems to come across like this. I will get one of the charts and give it a try. I get nervous now as I am being called to do more interviews..... which I think will be simple...Right? I'll try anything.

Thanks
Click to expand...

That's my issue exactly- it's a mid range thing on interviews that has burned me. I'm still using my old SD CRT monitor (8 inch) and the loss of focus can be hard to detect. As of late I've started bringing my NEBTEK as well and cranking the sharpness to full. Once my Putora chart gets here I'm going to give it another try. I have a 42 inch plasma that I'm going to hook into (if I can) for the BF adjustment, hopefully that will eliminate any second guessing.
 
I just wrote Jan Crittenden to see if she could send some help our way, we'll see. I know she is slammed with all the AF 100 stuff but she helped for a long time on this thread. There are to many people with the same issue, I hope we are just missing something. Stay tuned for a response.
 
I have noticed similar issues with the factory lens on our camera as well. Zoom in set focus pull back set back focus and occasionally have issues with middle distance softness. This issue popped up for the first time last January and again over the summer. We now religiously check back focus with every shoot now. Often times we check it several times throughout the shoot day. I will be curious to hear what may be the cause of this issue. I am not an expert on this camera by any stretch but I feel like once you set back focus during a shoot you shouldn't have to continually worry that your shots are going to look soft once you get them back to the edit bay. We typically shoot scene file 1 at AVC-Intra 720p60. Jan I will be most interested to hear what solutions you may have. BY the way placed my order for an AF-100 after seeing Barry with his rig at a VSA Houston event. Looking forward to making more beautiful images with Panasonic products.

Sincerely,

Alex
 
Well first off I am am going to point toward the lens. When working with smaller imagers with fixed lenses one can put into the firmware of the camera lookup tables for maintaining backfocus through the range of the lens. When working with interchangeable lenses, the issue becomes manual, and herein I believe is the rub. When we brought the HPX500 to the market the lenses that Canon and Fujinon brought out were break-thru products as far as prices and performance, and they were in the $8,000 range. Now this camera comes out and it includes a lens for a little more than what was the cost of the HPX500 lens. I will be talking to Fujinon over the next week or so about this and I am pretty sure that they will answer that you get what you pay for, as they do have lenses which do cost significantly more, that probably behave better. But I will post back what I hear.

In the meantime, check your shots.

Best,

Jan
 
Just to chip in I checked my back focus again this week on my HPX301 as I had the lens off to fit a nikkor lens.

Mine always seems to be fine and I just got the pro res HQ graded copy of a feature film I did last year and the images are quite superb on the 37" LG TV I have.

I know that fujinon had a bad batch of TH16 lenses with the JVC cameras a few years ago so maybe there is a few rogue TH17 lenses out there but as for fine it is OK but I also have the camera set-up to BBC spec and never go above f5.6 or +6db gain.
 
Hallo romy. Here is my method to set backfocus, and i assure you that is 100% working on my lens. Maybe you can give it a try...
First of all i do my backfocus at 1080i not 1080p. For me the interlaced works better.
Then i set the camera position not so far away from the chart. About 1,5 meters ( i'm in Italy, i don't now how much feet are! ). When i'm in wide position i have to see my chart and a little bit of the background. Remember that when the lens is in focus at wide angle and telephoto the lens still manteins this setting and the distance doesn't matter too much. But you don't have to stay too much closer to the chart. This distance works for me. Then i completely open my iris. Usually i prefer to not use ND filters.After this i unlock the backfocus ring and zoom in telephoto on the chart. I set the focus on the chart. I use the camera lcd to look at the picture, for me is absolutely simple to set focus in this way. When you are in focus the edges of the chart stands out in a really beautiful way. I use to move the focus right and left, just to see the difference. When you find the better picture.... you are in focus! Now i zoom out in wide angle. Generally and fortunately for most of the time the lens is stiil in focus, but i move the backfocus ring just a touch to see the difference. You can easly note on the camera lcd that edges stand out when you are in focus. But you have to see your chart!!! (I've noticed that you are too far away from the chart). Ok now zoom in tele again and check the focus. I move the ring a touch to see the difference. Differences are important! Zoom back again, check and lock the backfocus. I have to be onest... sometimes happens to me to set the backfocus in completely wild situations! And all the times the lcd saves my life! I have never touch the lcd settings. I've only set the luminance of the screen in the middle position and not on the standard middle value ( i' ve noticed in low lights strange lines in the lcd. You have to move back the lightness slider one time and it still remains in the middle but changes the color from green to white ). You can use to help your backfocus the focus bar. I know that this is a bizarre option but if you don't know this bar works in wide angle not in telephoto. When you set the focus in telephoto the bar stays in the left corner. But when you go out in wide the bar moves to the right. If the bar is over the middle range ( not on the extreme right,i've noticed that this never happens to me! ) you are in focus.
Sorry for my long reply but i think that you have to try again the backfocus setting. If your problem persists try another lens.

Bests,
Roberto
 
chancenorris said:
So what is the verdict on the the stock lens?
Click to expand...

I think it is very good considering you virtually get it for free with the camera.

I have done a low budget indie feature film on this camera and lens, the premiere was at the odeon cinema Harrogate and the pictures on the big big screen looked pin sharp to me.

it was shot 1920x1080i 25np AVC Intra 100 which went natively into FCP and the graded master was a pro res HQ file.

Trailer is here: http://www.youtube.com/watch?v=OG5hUYMTBx0
 
Hope you get this sorted mate - do keep us posted. Hate to say it, but it has never crossed my mind that I have this issue on mine - and I'm almost always working flat out iris too. Best of luck. Have shot loads on it by now as it was the first in the country I believe too! BD
 
This is very interesting, I am new to this camera (HPX370). When I received my camera
I set the back focus using the directions that came with the lens. It was pretty straight forward,
I have set back focus on other cameras (Sony) so I had some idea what to look for. I had no issues
with the focus until I started reading this post. Of course I went back and checked the back focus on
my camera and found it to be just the way I set it the first time. I know the supplied lens
are not, shall we say, the top of the line but mine seems to be fairly stable. Now I know I will
need to keep an eye on it.
Scott
 
Overall, 1/3" cameras tend to have tighter tolerances than 1/2" or 2/3", so it's also easier to throw them out of whack. For example, the macro ring on the kit lens has a very slight play to it and you can throw backfocus off if you apply some torque to it when it's in the locked position.
 
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