A1 grainy picture problem

[Khoi Pham]

That is weird, are you sure you don't have any heat source in between your camera and that bus stop? like over a car or something like that?

[Paul Cronin]

Sounds just like what I am seeing on my clips. I am going to down load a clip in a few minutes.

I had to down convert to SD and keep it short so it would download. But you sure can see the problem and it sounds just like what Khoi is seeing.

[Steven Cowie]

Paul, thats weird, whenever i click the link i posted it sends me to mega uploads where i get a web page as per screengrab below

http://i33.photobucket.com/albums/d8...101/megaup.jpg

then its just a case of entering whichever 3 letter code its asking for near top right of that page and waiting 45 seconds or so before download is allowed to proceed

Khoi, the road outside is actually pretty low on traffic for once (the clip i posted was when no traffic was passing by), no cars parked below the building, rumbling past or stuck in taffic belching fumes, its quite sunny outside but i wouldnt term it all that warm

When we first noticed it initially a few weeks or so ago the weather was a lot cooler still and I got a mate to duplicate it shooting a field that backs directly onto his house which is in a fairly isolated area.

Id post a different viewpoint, but where I'm shooting from today I'd have a tree or a building run smack into the frame if I repositioned the camera (the view thru to that bus stop is thanks to a gap in an otherwise built up street opposite me)

[Paul Cronin]

Steve that is the same problem I was seeing with the A1 camera I sent back. At full zoom it is bad but I still noticed it at full wide just not nearly as severe. Look at my clip and you will see the same thing.

[Paul Cronin]

Steve I just received an e-mail from Canon Service Center stating there is a problem with my A1. They are going to repair and send back within 7 days.

[Steven Cowie]

thats good news Paul (well not really but better than them telling you theres nothing wrong hehe) I'll see about getting something sorted out regarding our two

I'd be interested to see a small clip of the after repair once you have it back

Stevie

[James Hooey]

I get the same heat wave like imaging at long distance, mid to extreme zoom...I wonder out loud how much of this is simply HDV and high def in general showing thermal currents.
Gonna watch this thread closely.

[Nathan Quattrini]

I just thought i`d jump in to say hey to a fellow Rhode Islander. I`m thinking to get an A1 very soon as well, and had a nightmare last night about something kind of similar to this problem... more looking like Steves video....eek!

[Paul Cronin]

Steve I will go to the same location at the same time of day and do a test. With the new camera early in the week and the repaired camera when it arrives. I am ready now but will post a clip the same day. Was the size of the clip big enough to see the problem?

Steve this was the e-mail from Canon:

Dear PAUL :
"We have received your equipment for evaluation and repair. Based on our initial examination, we will start the necessary repairs at no charge to you. You can expect the repair to be completed and returned back to you within approximately 7 business days* from the date shown above. There is no need to respond to this notice."

James this is not do to being HDV. My sony Z1 was sharp at the same zoom and the water was 45 degrees and the air 50 degrees so it is not heat. Also I shot the HV-20 along side with crisp results.

Nathan I would go for the A1 and not worry. If you have a problem in the first week (when you should shoot a lot of footage) then you can send it back. But I think what Steve and I are seeing is rare.

[James Hooey]

Paul,

As mentioned above in my previous post....I've seen the same thing with my XHA1 so....

When I get a chance I will post a quick video of the same anomally...

I was shooting a distant rockface off Georgian Bay Ontario...currently 35 degrees farenheit. It was a sunny day with a rocky beach between me and the face and I had a forground rock I was using for a depth of field interest point.

My suggestion that it may be thermal related is actually what I HOPE is wrong with the shot. If it's the camera then I have a bigger problem. If i remember correctly in your shot you were showing a boat at a fair distance with a grassy field between you and the water.....what about the heat from that field on a sunny day? I'm no physic major but I thought that thermal shifts from one extreme (ie: the water) to another (sunlit field/rock beach) could just as readily cause this phenomenon.

I'm certainly not saying your incorrect however. Canon service on your part seems to consider there being some sort of problem. So my consideration is....what is the final outcome and reason behind the problem....hence the ....I will watch this thread closely comment. I don't want to consider there being a problem with my cam but if there is a reasonable explanation then I had better get mine sent away for service too.

All the best and hope things go well for you.

[Scott Saracen]

Hey there, another Rhode Islander here.
Have you or has anyone had these results indoors?

I have to say that everything I have shot so far has looked clean. The only time I noticed something similar was when I was shooting sunset across the bay in Bristol at full tele, and just chalked it up to heat waves.

Hope everything works out when you get it back.
I think I'm gonna go put mine to the test now, make sure it's all good.

[Steven Cowie]

paul re the clip at same spot - cheers for that be much appreciated (though to be honest just your opinion on it would be sufficient anyway given you'll have had a chance to see both the before and after)

Scott - Ive never had the issue rear its head when the object of interest is at short distance - 4, 5, 6 metres (even with zoom maxed out) at the other extreme I've shot footage of small objects at max zoom from a metre and a half indoors and results are fine

It only starts to get messy when when using 15x to 20x tele end of the lens and focusing on an object 30+ metres distance away

James - For myself its not really an issue in day to day shooting we tend to sit towards wide end of the lens (with 4 or 5x zoom being used at most)

If Paul hadn't raised the issue and got a 'does seem faulty' response from canon Id probably have continued to ignore it, but with Canons response to Paul then like yourself I'm more concerned as to whether the cameras are out of spec and something that could get progressively worse as time goes on etc.

I've shot same scene at night to try and rule out any thermals Theres been no traffic using the road outside for at least an hour and with sun long departed its cold enough around here now to need a heavy sweater while standing at the open window :)

http://www.megaupload.com/?d=WK4M1N6H

f3.4 1/25 shutter speed gain is +12dB, OIS is off and manual focus is on - doesnt exactly look pretty but shows the 'pulsing' effect

stevie

[Erik Palm]

I have used mine for three months have had it repaired once already due to backfocus problems. http://www.dvinfo.net/conf/showthread.php?t=87777
Now a grainy picutre as well. I use preset 17 natural look.

There seems to be poor quality of some ofthe XH-A1 - "Monday" versions - the Canon workers are hang over or something.
Now I am on a reportage trip and have to deliver grainy material from beautiful Norway - feels terrible.

Any quick solution?

When I get back I will try to get another sample of the A1 - a Thursday version or so I hope./Erik

[Paul Cronin]

Wow this seems to be happening to quite a few A1's.

James I have tested the same as Steve with no heat at dusk with the same results set up to my component 24" HD monitor. So I do not think it is the heat.

HI fellow Rhody Scott. Sounds like you have the same problem at max zoom.

Steve no problem posting a clip. I hope this is not a flaw with the A1 since I need 12x -20x often.

Erik do you have a clip showing the same problem?

[Piotr Wozniacki]

Regarding "is it a heat convection wave or not" issue: I never had an opportunity to try the A1 at full telephoto and with focus at infinity, but I did with the V1, and am getting very bad results sometimes, like in the attachement I posted here:

http://www.dvinfo.net/conf/showpost....10&postcount=5

I said "sometimes", because I can also get close-ups that are perfectly clean, with no crawling vertical edges, shimmering etc.

So, after all, I do think it's the heat. The current air temperature alone is not enough to determine the convection "should" be visible or not; the temp gradients, humidity and air pressure can also play a role, I guess.