DSLR 101 2.0

[ebiggs1]

Maybe you will like these better.  I try to please! 

All with my best of class, 1.3 body the EOS 1D Mk IV.  Birders favorite camera!  I love this camera. 

[jazzman1]

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@ebiggs1 wrote:

First off you are not using your head.  In one case the camera is supporting the lens.  In the other the lens is supporting the camera.  Does that not make sense?  I guess it does boil down to which is heavier.

The longer the lens gets, the more it acts like a lever.  So the weight increases dramatically.

If I'm reading you correctly, you don't understand my question.  What you say here is correct.  What I'm asking is if it's a difference in "the weight" of the "lens" on the "camera mount"...whether the camera is attached to a sling strap, or the camera is mounted on a tripod.  In both instances the lens weight is bearing on the camera lens mount., right?????? 

All lenses have some distortion.  Either pincushion or barrel along with some other stuff.   The photos I corrected for you were user error.  Plus LR automatically corrected for the rest of the ungoodies the lens has.

There are two things here that effect distortion.  One is you didn't hold the camera horizonal.  Which you didn't.  The other is perpendicular to the subject.  Which you didn't.  The first is easy to fix in LR.  The second is not.

You must see your lens as a cone accepting light rays.

Look at this.  It shows how that type of distortion would effect you photos

Comprende amigo?  

You're the Pro here and I cannot refute your facts, nor would I try.  But just wanna ask you to go back and look at the 4th pic of the JSV Jazz Fest I posted on page 4..   The picture with the water taxi boat.   Look at the building across the other side of the river.  The building on the far right is either straight, or seems to lean a tad to the right (to me).  Now look to the far left and see a pronounced lean to the left of that building (the greenish bulding).  That's the way it looks to me on my screen.   You tell me if you see what I'm referring to.   If this is so, how could I have caused 2 buildings to lean in opposite directions???    If I'm correct, this is from distortion not me.  If not, I stand corrected and will accept your explanation.  BTW....I took those shots with my Canon 24-105mmL and hood.  I would not expect this kind of distortion with this lens.  Actually, I've been studing all those pics all week, and most look good to me far as being straight.

I'm not talking about the lens supporting the camera from the sling strap attached to the lens, I'm talking about the camera supporting the lens in both instances, by the sling strap attached to the camera tripod mount, or the camera attached to a tripod.  Do I make sense????

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[jazzman1]

This brings up another question???    What supports the heavy lens (L's) weight, when the camera and lens is on a tripod????  Only the camera right???   If there's another acc for supporting a big heavy lens when the camera/lens combo is on a tripod you have'nt ever mentioned that.

[ebiggs1]

"I'm not talking about the lens supporting the camera from the sling strap attached to the lens, I'm talking about the camera supporting the lens in both instances, by the sling strap attached to the camera tripod mount, or the camera attached to a tripod.  Do I make sense????"

No, it doesn't but I don't know any other way to explain it.  The support comes from the mount and where you put it.  If on the cmera it bears all the weight.  On the lens it bears all the weight.  The lens could weigh a thousand pounds and the camera would not feel it if the lens was used for support.

[RobertTheFat]

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@jazzman1 wrote:

This brings up another question???    What supports the heavy lens (L's) weight, when the camera and lens is on a tripod????  Only the camera right???   If there's another acc for supporting a big heavy lens when the camera/lens combo is on a tripod you have'nt ever mentioned that.

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It's usually a ring containing a tripod socket. It surrounds the lens and can be loosened to allow you to position the camera either horizontally or vertically.

You usually want the mounting point to be as close as possible to the center of gravity of the camera/lens system. If the lens is long and/or very heavy, the COG will be somewhere along the barrel of the lens; so that's where the ring goes. If instead you attached the tripod to the camera, the lens would act like a strong lever and try to distort the face of the camera. If it succeeded, part or all of the image would be out of focus. If the distortion got to be permanent, you'd need a new camera.

[jazzman1]

I agree with all you've said about the lens weight.  I said I did when you 1st told me, I even got the Sling Strap and Canon Lens Ring.   It just dawned on me that the lens bares the same amount of weight on the camera when mounted on the tripod.   I wondered did this mean that it's Ok for the lens weight on a tripod, and only not Ok carrying lens attached to camera with sling attached to camera tripod mount.  I figured there must be something here I'm not understanding.  I see many guys in my clubs (many more than I can count)  using bigger L lens than I have, using a tripod/monopod only.  Guess I'm saying does using a tripod, in some way......makes it Ok for the lens weight on the camera???   Not trying to be difficult here Obiwan, I never am with you.  I'm just trying to understand.      Your answer here may change how I use any heavy lens with my camera on a tripod now.   Just seems something I must not be understanding.

[ebiggs1]

"The picture with the water taxi boat."

I made specific comments, only, on the two photos I corrected. None of the others.  When you hold your camera croocked or out of square, if you will, there is no way of telling what caused the distortion.  Did you not look at the three lenses I drew for you?

You have a curved surface and a flat plane.  When you are not perpendicular to that, you get distorted lines.  All your photos look like they are not horizontal.  And likely not perpendicular to the subject.

Most of this, if not all, is correctable in PS, not LR, however.  For the most part it is imperrative to keep straight lnes that run through the center of the lens straight.  Horizontal and perpendicular.

The photo below was shot with a 15mm lens.  All WA lenses have severe distortion if not used correctly. Yet the photo looks straight because the horizontal and perpendicular lines going through the center are horizontal and perpendicular.  Plus I am not holdin the camera crocked or crooked.

[ebiggs1]

" Not trying to be difficult here Obiwan, I never am with you."

I am at the end here as I don't know how else to put it.  Do as you like it will be fine.  

[jazzman1]

It's usually a ring containing a tripod socket. It surrounds the lens and can be loosened to allow you to position the camera either horizontally or vertically.

You usually want the mounting point to be as close as possible to the center of gravity of the camera/lens system. If the lens is long and/or very heavy, the COG will be somewhere along the barrel of the lens; so that's where the ring goes. If instead you attached the tripod to the camera, the lens would act like a strong lever and try to distort the face of the camera. If it succeeded, part or all of the image would be out of focus. If the distortion got to be permanent, you'd need a new camera

That's why my privious post.   It seemed to me the weight on the camera would be the same on a tripod also, and wondered if I should start doing something different when using my camera/lens combo on my tripod/monopod.  Usually I have been letting the tripod hold the combination, but now I'm really considering someway to support my heavy lens when using my tripod/monopod.  If nothing other than using my left hand under the lens for support.    I have the canon lens ring mount as you know, and thought maybe I would'nt attach the camera to the tripod, but just sit my lens on top of the tripod, and let the tripod support the lens/camera combo under the lens ring mount.   That ring mount has a small arm that I can use to set the lens on top of the tripod with.   I would have to continually hold my camera, could'nt let it go in this position.   What do you guys do when using a tripod/monopod, you have much heavier Zoom Lens that I do????

[jazzman1]

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@ebiggs1 wrote:

"The picture with the water taxi boat."

I made specific comments, only, on the two photos I corrected. None of the others.  When you hold your camera croocked or out of square, if you will, there is no way of telling what caused the distortion.  Did you not look at the three lenses I drew for you?

You have a curved surface and a flat plane.  When you are not perpendicular to that, you get distorted lines.  All your photos look like they are not horizontal.  And likely not perpendicular to the subject.

Most of this, if not all, is correctable in PS, not LR, however.  For the most part it is imperrative to keep straight lnes that run through the center of the lens straight.  Horizontal and perpendicular.

The photo below was shot with a 15mm lens.  All WA lenses have severe distortion if not used correctly. Yet the photo looks straight because the horizontal and perpendicular lines going through the center are horizontal and perpendicular.  Plus I am not holdin the camera crocked or crooked.

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All this now is very important info for me.   I never knew the things you're saying  It will help me use better posture and framing now.  I always knew that one should squire a pic up in the viewfinder and keep lines straight.  But I never knew till now all the problems can be caused from not framing a scene correctly.  Did'nt know it would create distortion.  I do know that many lens create some distortion at the widest angle, but none of the pics I've posted were at the wide angle on my lens.   As I said I used my 24-105 L for the jazz fest shots and most shots were from mid to farthest range.   I did not know till now that we can cause distortion with our pics from using bad form.

None of my questions here had anything to do with me thinking you told me anything wrong.   But I really needed answers so I would know how to proceed.  This tells me I have to think about my camera stance and really pay atention to lines in the viewfinder.   As I said, I'm not trying to be difficult only want to understand, and do things right.

It would be good to know if you thought the taxi boat pic was Ok, cause that pic looked distorted and I did'nt think it was from anything I did.  That's why I asked you to take a look at it.  thanks for your answer.

If my questions have you at your last nerves, I'll ask you no more about it.  I told you I get bent outta shape when I think I'm not doing things right. 

[jazzman1]

Bob thanks much for your answer here.  I have such a hole on my Canon lens ring mount.  No directions came with the ring mount and I thought that hole was only for the sling strap attachment.   I had no idea that hole was for a tripod quick release plate.   That is what you mean right????        Now the light bulb came on and all my questions are answered and it all makes sense.  Now I understand how to attach my lens to my tripod.  No one had explained that to me.  Not Canon (no directions came wiih the ring mount)  Nor Biggs....I never knew till now, that's how to use a heavy lens on a tripod.  Biggs probably took for granted I should know this.  But this is the 1st heavy L lens I've ever owned.

And the clincher here, is that I still would not have known this had I not pursued my questions.  Sorry if I caused you guys any headache.