Viewfinder Horizon/Paralax? HELP!! at DVinfo.net

Graham Bernard · April 29th, 2003, 09:20 AM

Okay Guys 'n Gals,

I've been sickling with this for far too long.

I can get a vertical - a door frame - in the viewfinder to line up, say, on the left hand side. When I pan and get the door frame into the centre of the vf it appears to be at least 5-8 degrees off the vertical COMPARED to the the real doorframe when seen from the NON-eyepiece open eye - yeah? Surely this is very unatural?

If you need a further explanation of this I'll give it another go.

Anyway, solutions, ideas etc . . gratefully accepted.

Grazie

Chris Hurd · April 29th, 2003, 10:44 AM

Graham

At what focal length? Full wide? If so, then you're probably seeing a bit of barrel distortion at the edges of the lens. Try zooming in just a bit (you may have to move the camera back).

Are you directly on axis with the door? In other words, can you draw a straight line parallel with the walls from the door to your tripod.

Graham Bernard · April 29th, 2003, 11:51 AM

"At what focal length? Full wide?" . . and tele.

"...a bit of barrel distortion at the edges of the lens. . . " No, I don't think so, I get this 5 degrees out when straight onto subject.

"Are you directly on axis with the door? ... " . . errrmmmm, yes I guess so . . . no tripod - hand held.

A little more explanation - ahem.....

1 - I'm comparing that which I can see with my non-eyepiece eye - ie my left eye, with my eyepiece eye - my right eye.

2 - When the subject is the thin edge of the door - edge on - when I get this "vertical" front and centre, in the eyepiece, and compare this with "reality" - ie with my left eye open - it is at about, in terms of a clock face, at about 4mins to the 12 o' clock mark for the eyepiece - yeah?

Put simple, what is appearing to me is that the viewfinder appears to be rotated about 5 degrees anticlockwise to the subject. That's what I mean!

Thanks for your patience,

Grazie

Chris Hurd · April 29th, 2003, 12:20 PM

Graham, I think the best way to approach what is going on is to mount the camera on a tripod which includes a bubble level, and make absolutely sure that the camera is dead level with the floor. Because if you're seeing this when hand-held, my first reaction is that there's a chance you might be holding the camera with just a bit of a tilt? Or am I still reading this wrong?

Wayne Orr · April 29th, 2003, 12:57 PM

And posting a still or two of the "problem" is in order.

Chris Hurd · April 29th, 2003, 01:54 PM

Wayne Orr wrote:

<< And posting a still or two of the "problem" is in order. >>

Agreed. Graham, if you don't have your own website to upload to, just email the images to me and I'll host them for you. Hope this helps,

Graham Bernard · April 29th, 2003, 03:46 PM

I'll get on it tomorrow - It's now 10:45pm and I've had a long day!!!

Your email is?

Grazie

Ben Lynn · April 29th, 2003, 03:51 PM

There may be some technical reasons why it's off, but as long as it's straight in the viewfinder does it matter? The viewfinder is the ultimate judge of level so go with that.

Ben Lynn

Graham Bernard · April 29th, 2003, 03:56 PM

JUST 'bout went to bed! - Good point Ben!

But, at long last, I've trained myself to have both eyes open. Useful to scan the real world for what is going on - yeah? - Now doing this gives me the "skewed" view on the world and this in turn makes me "correct" towards "5mins to 12 '0Clock".

Grazie

Graham Bernard · May 2nd, 2003, 11:38 PM

Have done a lot of experiments. Thanks Chris! - Made a MS WOrd Target and stuck it on a wall - with a spirit level. Saw what was happening in the viewfinder - NOTICED how I compensate to "actual" verticals and now I ignore them. I think, I really do think . . . how can I say this . . . .ooohh this is truly embarrasing . . . . I think I was treating the VF as that which I have on my SLRs stills cameras, I 've had over the centuries - "Line up a vertical in the VF with that which you can see through the VF!" - THERE I'VE said it! OKAY!!! - If I do this, I then get a 8 or 10 dergree list to the left - anticlockwise rotation. IF I now line up the vertical IN the VF - say to the left hand edge - no problem - well I shouldn't, should I.

Now here's a wheeze I've now incorporated to "assist" my technique - I'm now using the 16:9 wide screen guides as an additional horizontal "check" for the horizontals - yeah? It works and has kept me, "Level Headed!" - neat eh! I'll use them until I've got it truly drummed into my brain synapses. I'm using these guides much the same as a youngster would use "stabilisers" on their first bicycles - once learnt I'll unbolt the 16:9 guides and free wheel.

As a result, I think I've shot some of the best level footage so far. I still don't understand WHY I can't use the SLR example to "get" straight up stuff - but hey what do I know!?! I realise that the VF is only a little TV screen, and in essence it doesn't "relate" to the reality of comparison, exo-XM2. That is "You Shoot What You See In The VF". I know I can "twist" the cammy about and have the VF "monitor" where the actual verticals/horizontals appear. Even still . . . . .

Chris thanks for "pushing" me to go experimental with the "Spirit In The Sky" test. Without this I would have still been floundering about. I haven't sent you any "stills" - yet! If you still [ ;-) ] wish to have something I'll do it.

Thanks Guys 'n Gals for your patience with me - I'm going to do some more filming soon, in deepest North Norfolk - very flat scenery there, against the North Sea - lots of horizions! - If I can't get it right with this type of countryside, there's no hope for me - JOKE!

Oh yes, OT: Sony to buy Sonic Foundry! My Vegas NLE suite will at long last have some financial backing and a Worldwide presence . . . hmmm.... interesting. I own a Canon XM2! Could Sony be making a play for THE Create to Deliver platform of the 21st Century? - They've already got an amazing Laptop - Vaio!

Think on Canon!!!

But that''s another story . . . .

Grazie

April 29th, 2003, 09:20 AM	#1
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	Viewfinder Horizon/Paralax? HELP!! Okay Guys 'n Gals, I've been sickling with this for far too long. I can get a vertical - a door frame - in the viewfinder to line up, say, on the left hand side. When I pan and get the door frame into the centre of the vf it appears to be at least 5-8 degrees off the vertical COMPARED to the the real doorframe when seen from the NON-eyepiece open eye - yeah? Surely this is very unatural? If you need a further explanation of this I'll give it another go. Anyway, solutions, ideas etc . . gratefully accepted. Grazie

April 29th, 2003, 10:44 AM	#2
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,368 Images: 513	Graham At what focal length? Full wide? If so, then you're probably seeing a bit of barrel distortion at the edges of the lens. Try zooming in just a bit (you may have to move the camera back). Are you directly on axis with the door? In other words, can you draw a straight line parallel with the walls from the door to your tripod. __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

April 29th, 2003, 12:20 PM	#4
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,368 Images: 513	Graham, I think the best way to approach what is going on is to mount the camera on a tripod which includes a bubble level, and make absolutely sure that the camera is dead level with the floor. Because if you're seeing this when hand-held, my first reaction is that there's a chance you might be holding the camera with just a bit of a tilt? Or am I still reading this wrong? __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

April 29th, 2003, 12:57 PM	#5
Wayne Orr Major Player Join Date: Dec 2002 Location: Northridge Ca Posts: 734	And posting a still or two of the "problem" is in order. __________________ Wayne If it was easy, they'd get a relative to do it.

April 29th, 2003, 01:54 PM	#6
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,368 Images: 513	Wayne Orr wrote: << And posting a still or two of the "problem" is in order. >> Agreed. Graham, if you don't have your own website to upload to, just email the images to me and I'll host them for you. Hope this helps, __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

April 29th, 2003, 11:51 AM	#3
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	"At what focal length? Full wide?" . . and tele. "...a bit of barrel distortion at the edges of the lens. . . " No, I don't think so, I get this 5 degrees out when straight onto subject. "Are you directly on axis with the door? ... " . . errrmmmm, yes I guess so . . . no tripod - hand held. A little more explanation - ahem..... 1 - I'm comparing that which I can see with my non-eyepiece eye - ie my left eye, with my eyepiece eye - my right eye. 2 - When the subject is the thin edge of the door - edge on - when I get this "vertical" front and centre, in the eyepiece, and compare this with "reality" - ie with my left eye open - it is at about, in terms of a clock face, at about 4mins to the 12 o' clock mark for the eyepiece - yeah? Put simple, what is appearing to me is that the viewfinder appears to be rotated about 5 degrees anticlockwise to the subject. That's what I mean! Thanks for your patience, Grazie

April 29th, 2003, 03:46 PM	#7
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	Ah - Thanks Gents! I'll get on it tomorrow - It's now 10:45pm and I've had a long day!!! Your email is? Grazie

April 29th, 2003, 03:51 PM	#8
Ben Lynn Major Player Join Date: Mar 2003 Location: Bloomington, IL Posts: 636	There may be some technical reasons why it's off, but as long as it's straight in the viewfinder does it matter? The viewfinder is the ultimate judge of level so go with that. Ben Lynn

April 29th, 2003, 03:56 PM	#9
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	JUST 'bout went to bed! - Good point Ben! But, at long last, I've trained myself to have both eyes open. Useful to scan the real world for what is going on - yeah? - Now doing this gives me the "skewed" view on the world and this in turn makes me "correct" towards "5mins to 12 '0Clock". Grazie

May 2nd, 2003, 11:38 PM	#10
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	Cracked It! - Not the Camera! Have done a lot of experiments. Thanks Chris! - Made a MS WOrd Target and stuck it on a wall - with a spirit level. Saw what was happening in the viewfinder - NOTICED how I compensate to "actual" verticals and now I ignore them. I think, I really do think . . . how can I say this . . . .ooohh this is truly embarrasing . . . . I think I was treating the VF as that which I have on my SLRs stills cameras, I 've had over the centuries - "Line up a vertical in the VF with that which you can see through the VF!" - THERE I'VE said it! OKAY!!! - If I do this, I then get a 8 or 10 dergree list to the left - anticlockwise rotation. IF I now line up the vertical IN the VF - say to the left hand edge - no problem - well I shouldn't, should I. Now here's a wheeze I've now incorporated to "assist" my technique - I'm now using the 16:9 wide screen guides as an additional horizontal "check" for the horizontals - yeah? It works and has kept me, "Level Headed!" - neat eh! I'll use them until I've got it truly drummed into my brain synapses. I'm using these guides much the same as a youngster would use "stabilisers" on their first bicycles - once learnt I'll unbolt the 16:9 guides and free wheel. As a result, I think I've shot some of the best level footage so far. I still don't understand WHY I can't use the SLR example to "get" straight up stuff - but hey what do I know!?! I realise that the VF is only a little TV screen, and in essence it doesn't "relate" to the reality of comparison, exo-XM2. That is "You Shoot What You See In The VF". I know I can "twist" the cammy about and have the VF "monitor" where the actual verticals/horizontals appear. Even still . . . . . Chris thanks for "pushing" me to go experimental with the "Spirit In The Sky" test. Without this I would have still been floundering about. I haven't sent you any "stills" - yet! If you still [ ;-) ] wish to have something I'll do it. Thanks Guys 'n Gals for your patience with me - I'm going to do some more filming soon, in deepest North Norfolk - very flat scenery there, against the North Sea - lots of horizions! - If I can't get it right with this type of countryside, there's no hope for me - JOKE! Oh yes, OT: Sony to buy Sonic Foundry! My Vegas NLE suite will at long last have some financial backing and a Worldwide presence . . . hmmm.... interesting. I own a Canon XM2! Could Sony be making a play for THE Create to Deliver platform of the 21st Century? - They've already got an amazing Laptop - Vaio! Think on Canon!!! But that''s another story . . . . Grazie