Let's get reed of LF shall we?

[theodoros_fotometria]

<p>Q: Why is leaf shutter still there...?<br /> A: Because more than half a century ago, shutter curtains where not fast enough to support strobe use...<br /> Q: What if focal plain shutters where faster....<br /> A: The sync. speed of strobes is in direct relation with the ability of a focal plain shutter to "cover" the sync speed, the faster a focal plain shutter can move, the sync speed will follow!<br /> Q: Do we need LS if focal plane shutter was as fast?<br /> A: No!<br /> Q: What is the fastest sync speed a master photographer would use?<br /> A: During the (recent) past, that was 1/500sec, but it was rarely used, most experienced photographers used (less than usual) up to 1/250, for fill in.<br /> Q: Do modern photographers use more than 1/500?<br /> A: No! (not with strobes anyway)... If one claims that he does, it's only for "showing off" reasons, there are other ways to cope with extreme light situations, which are more effective!<br /> Q: Can a focal plane shutter DO 1/250 with MF?<br /> A: Most probably yes! ...But makers never demanded it (from Copal or others), they prefer to offer in lens shutter systems and charge you (a lot) for it... It makes lenses "slower" too.<br /> Q: If sync speed was the same when in focal plane and in LS... which mode should I prefer? <br /> A: LS, <em>doesn't have an even distribution of light on the </em><em>image, ....depending on the shutter speed, light is more to the center and gradually falls towards the e</em><em>d</em><em>ges, (vignetting), </em>the more the shutter speed, the more the problem is relevant, focal plane has none of these issues, just that it was (up to now) slower!<br /> Q: If my lenses didn't have LS in them would they be cheaper and would they be faster?<br /> A: This is obvious...<br /> Q: So who is preventing Copal (or any other) to come with faster shutters (let's say 1/250sec) and sync strobes with that MF speed, that would make LS uneccesary...?<br /> A: Nobody has asked for it!<br>

<br /> Your call (MF) people!</p>

[User_6502147]

<p>OK Mr. Maverick....you can still enter the door for DPR....as the door here at MF is slammin you in the back. I'm trying to be polite.</p>

<p>Les</p>

[theodoros_fotometria]

<p>.......................................................???? "<em>Mal a la tete</em>" Les?</p>

[john tonai]

<p>I think the absurdity of your post is what caused our headaches</p>

[richterjw]

<p>I don't understand why so many of these statements are exclamatory in nature!?</p>

[rodeo_joe1]

<p>One big hole in argument. Leaf shutter not vibrate due to low mass and inertia, and due to rotary action with respect to camera/lens axis. FP shutter vibrate big time because of big mass, big inertia and linear direction of movement transverse to camera body/lens axis.<br>

Q: Can I dumb it down any further?<br>

A: I don't think so!</p>

<p>"LS, <em>doesn't have an even distribution of light on the </em><em>image</em>.." - Absolute crap! A leaf shutter works in almost the same plane as the iris aperture and doesn't cause vignetting. Sure its <em>efficiency </em>changes with shutter speed and aperture used, but that's an entirely separate issue.</p>

[jeff_livacich]

<p>I like the quietness and lack of vibration of a leaf shutter.</p>

<p>There is a valid application for both focal plane and leaf shutters. Why get rid of either?</p>

[starshooter]

<p>Cloud-coo-coo-land.</p>

[john tonai]

<blockquote>

<p>I don't understand why so many of these statements are exclamatory in nature!?</p>

</blockquote>

<p> <br>

Because the OP is telling us how we photograph and what WE need. I need as high a sync speed (with full power flash, not high speed sync) for key shifting. For him to say I don't need it, is pretty arrogant</p>

[theodoros_fotometria]

<p>Jeff, other than fast flash sync speed, quietness and lack of vibration is the only advantage that leaf shutters have, but not in SLR systems where the main source of vibration is the mirror. So with MF SLRs, you have to buy a Leaf shutter with every lens you use, buy a slower lens too, without having a benefit in vibration. Also... the cost rises a lot because you buy multiple shutters.... Thus, if sync speed of focal plane was faster (like it is with FF DSLRs) Leaf shutter would give no additional benefit. It's only in Large format systems that there would still be a reason to use LS designs (the way that view cameras are traditionally designed). In return, there is fall off caused by the leaf shutters (especially at higher speeds) which can be a problem if added to the lens natural vignetting at the wider apertures. </p>

[rodeo_joe1]

<blockquote>

<p>"In return, there is fall off caused by the leaf shutters (especially at higher speeds).."</p>

</blockquote>

<p>- Care to show us your evidence for this?<br>

The way it actually works is as follows: A leaf shutter opens and closes from the centre; i.e. the centre of the shutter opens first and closes last. This helps to actually <em>reduce</em> vignetting by giving preferential exposure to central rays passing through the lens and partially obscuring the outer rays. That's just like stopping down the aperture iris. The net result is that at larger apertures and higher shutter speeds the exposure is slightly less than it should be <em>all over the frame,</em> but vignetting is actually reduced.<br>

Q: Does stopping the iris down increase vignetting?<br>

A: No, it does not!<br>

Q: Can a leaf shutter therefore possibly increase vignetting?<br>

A: No, it cannot!<br>

Q: Are you making up spurious "facts" to support your argument?<br>

A: Yes, you are!</p>

<p>Do you really think that it's trivial to design a mechanism able to move two or more sheets of material, each several cm wide, from rest across a 6cm gap in under 2 milliseconds; then bring the whole lot to rest without undue stress and vibration, and to do that while regulating their movement accurately? Not only that, but the mechanism and material is expected to remain reliable for several thousand operations. If you think it's so easy then go ahead and design it. Because we're still waiting for the solid-state LCD shutter we were 'promised' over 20 years ago.</p>

<p>If you don't like leaf shutters, then simply buy a camera that doesn't use one. There are plenty around. Pentax67, Pentax645, Pentacon6, various Bronica models, Mamiya 645 series, the list goes on. Many systems allow the best of both worlds by having leaf-shuttered lenses available to fit FP-shuttered camera bodies.</p>

[theodoros_fotometria]

<p>What you are "trying" to say, would be true only if the leaf shutter was positioned at the same place as aperture or if it had a double role... (both shutter and aperture) and would need a symmetrical lens design, but because of your attitude (and bad language) I won't bother to explain it nor I will reply back to you again. Bye.</p>

[jeff_livacich]

<p>Theodoros, my medium format SLR has mirror lockup (actually a pre-release). And in non-SLR's, the advantage is clear. So why would a focal-plane shutter be put in a TLR or RF camera? Which means that we should NOT get rid of leaf shutters in medium format.</p>

<p>What's your trip, anyway? Are you just looking for an argument? Because you are making something which is not a problem into one. If you prefer focal plane shutters there are plenty of options.</p>

<p>But I know very well that I have never had vignetting caused by a leaf shutter. The theory is contradicted in actual practice, as are other theories of lens design. Did you know that lenses are supposed to radically increase resolution as the aperture becomes larger? It can be shown mathematically. But reality is different, because lenses exist in the real world, not the world of optical theory.</p>

<p>You seem to have all the answers, and are hostile to being contradicted. Your snippiness to Rodeo Joe is unwarranted. Your mind is closed, and you are only interested in your opinions.When you make crap statements, it is not surprising that they are called just that.</p>

<p>Regardless of what you think, in the real world there is no vignetting from a leaf shutter. The shutter moves too quickly.</p>

<p>Finally, I know P.net prohibits posting a thread in more than one forum. It should be obvious that posting the same thread in the same forum is not allowed either.</p>

[john tonai]

<p>Jeff, now you've done it. You also said "crap", Now Theodoros won't reply to you either. Oh crap I said "crap"! Now he is going to ignore me also</p>

[paul_loveteck]

<p><a href="/photodb/user?user_id=6737431">Theodoros</a>,<br>

Although I have defended you lately, I disagree with you on this one on two points:<br>

1) The combination of LS with mirror lockup allows to avoid vibrations you cannot avoid with a focal shutter. This is even more important when using a digital back with their enormous definition.<br>

2) I think your answer to Rodeo is not very civil. Granted, Rodeo was not very nice, but it might be time in this forum to go back to the basics of civility.<br>

In fact, I believe that it would be wise to open a new discussion on civility on this forum. I know that the tone has been set a long time ago by a certain O.J. where insults and false accusations are flying as soon as you post something, only for the sake of contradiction, ignoring civility and the fact that somebody can make a simple mistake.<br>

John, Jeff, Theodoros, Rodeo:<br>

Can you agree that you disagree on this matter without needing to attack the person you disagree with?<br>

I hope that all of us in this forum are photography lovers. Should not this be sufficient to respect the other one and answer in a civil way, even if we are convinced he is wrong?</p>

[john tonai]

<p>Paul,</p>

<p>Because civility starts with NOT trolling. Instead of wondering why leaf shutters are still made, he posted in a manner that was meant to provoke. I did not get involved with this posting until he made his headache comment to Leszek. I disagree with many other people, like we all do, but Theodoros comes across like a bully.</p>

<p>From his OP:</p>

 

<blockquote>

<p>Q: What is the fastest sync speed a master photographer would use?<br />A: During the (recent) past, that was 1/500sec, but it was rarely used, most experienced photographers used (less than usual) up to 1/250, for fill in.<br />Q: Do modern photographers use more than 1/500?<br />A: No! (not with strobes anyway)... <em>If one claims that he does, it's only for "showing off" reasons,</em> there are other ways to cope with extreme light situations, which are more effective!</p>

</blockquote>

<p> <br>

What makes him the all-knowing master of what we need in shutters? I don't use more than 1/500 because that's the fastest shutters usually go, but if it went faster I could use it for more flexibility with key shifting with larger apertures-and not because I'm <em>"SHOWING OFF"</em><br>

</p>

[steve_mareno1]

<p>People, you're aware that the poster's name and whole schtick is a put on? and yes, bye bye T.F. Please do drop by again and shake things up a little.</p>

[paul_loveteck]

<p>John,<br>

Yes, I know and agree with you, however I believe that the best action when you have the feeling to be bullied is not necessarily to become a bully yourself as this only worsen the discussion and the chance for apology from somebody who maybe did not intend to be a bully. Also, keep in mind that English is not always the first language of many people in this forum, making them sometimes sound harsher than what they intend.<br>

By giving the benefit of the doubt you might often make a friend instead of an enemy.</p>

 

[steve_rasmussen]

<p>An obvious need here for a Moderator that participates in this forum. Posters should be wise enough to not post something that is very inflammatory. It reminds me of when I was in the corporate world in a meeting and someone would come in and say something outrageous and then leave, laughing all the way down the hallway at us arguing madly.</p>

<p>A Moderator needs to step in before the quid pro quo reaches critical mass. Also, in the past, Moderators could ban individuals if they refused to comply with Pnet's Terms of Use. Part of that is below. </p>

<p>We encourage the sharing of ideas and opinions on the topic of photography, but photo.net is not an "anything goes" website. Photo.net users come from all locations and backgrounds, and have diverse thoughts, beliefs, and feelings. Keep this in mind when you participate in the community, and treat others with respect. Postings that attack another person's motivation, intelligence, or character degrade the quality of the discussion and discourage thoughtful comments by others. There are many places on the internet where you are welcome to have moral or political arguments, however, in almost every case, photo.net is not one of them. Neither is this community a place for you to harass, abuse, threaten, or otherwise bother other members, and it's not a place for you to do anything illegal. We don't want to kick you out of the community, but if you do any of these things, we will. So don't do them.</p>

[rodeo_joe1]

<p>Sorry, I didn't think this was a<em> serious</em> thread that demanded absolute civility. If moderation were needed, it should have quickly stepped on this trolling and inflammatory thread before it had time to get out of hand. So it's a bit late now to call for everyone to chillax. Besides, I'm sure Theodoros is only playing the injured party to escalate the troll value of this thread - and it's working, isn't it?</p>

[andylynn]

<p>I would write a response to the OP about the usefulness of high speed flash sync and reduction of vibration but it would be pointless. The OP is trolling. He does this a lot. He's better at it than he is at talking about photography.</p>

<p>Theo, you should check out the DPReview forums. There are many of your people there, and you can spend all day engaging in pointless yet excited argument over trivial technical details.</p>

[steve_rasmussen]

<p>Joe, it may be too late to stop the battle on this thread but the reason I said that we need to stop inflammatory posts and abide by the "terms of use" is to prevent them from occurring in the future. Josh Root needs to establish a Moderator here. </p>

[Spearhead]

<p>Josh hasn't been with photo.net for several months. However, the original poster is no longer on this site and I will close this thread and remove it shortly. </p>