mirror lock up ?

Hi dear fiends,
so many times people complain that Drebel does not have a mirror lock up while 10D has. I have a 10D but have NO IDEA what this mirror lock up helps for!!. I know that documentation is arround for that but real tips are always in this forum
any enlightenment is very welcome
thanks in advance.

Essentailly.. mirror lock up is most usefull when taking images in lower light/slower shutter speeds with a huge telephoto! (or a super macro etc.. )

At 500mm or more.. even on a rock steady tripod.. to get "ultimate" sharpness... one may need to illiminate the "mirror slap" as a possible source of vibration. By locking the mirror up before taking a shot... you can do exactly that.

However in practise I find is usefullness limited. Rarely do I have an opportunity to take advantage of mirror lock up when I shoot with a telephoto. My subjects are moving most of the time.. and I don't have time to "deal" with the timing of the mirror lock up.

It seems to me that it is a rather secific application that can take advantage of the lockup... hardly something to be too concerned about.

Mirror slap is only a potential problem at a certain range of shutter speeds. You will get different opinions, but it is generally from about 1/4 to maybe 1/20 second. It can be just a little vibration that causes your image to be just slightly fuzzy despite the camera being on a tripod.

Why that range only?

Anything faster (like 1/30), and the mirror slap happens after the end of the shutter, so it doesn't matter.

Anything slower (like 1/2), and the mirror slap PERIOD is only a small portion of the total shutter PERIOD, so it doesn't contribute much.

But, in that narrow PERIOD, the mirror slap can be significant. Some cameras are worse than others, but just about all SLR cameras have it to some degree. You would not shoot anything this slow without a tripod, would you?

---Bob Gross---

Hi Sendide,

If you don't use your mirror lockup. I would certainly be happy to trade my Drebel for your D10. I'll even throw in an extra $150. I take most of my photos in low light conditions but just couldn't afford to get the D10. Every day I wish I had that silly mirror lockup.

If you are interested let me know!

Malok

Sendide did not claim to have a D10.

---Bob Gross---

I have lurked here for sometime, recently joined and became a member. I have posted in limited discussions but have learned an unbelievable amount from those on this Forum. In all that time I have seen your posts and they generally have an EDGE to them, such as the one above. Is it really needed? What do you gain from it? These posts remind me of "other" discussion groups and boards and are below the general sense of decorum that seems prevalent here. Just curious.

Thanks DReb-Mo,

I appologize if my comment was not constructive. If anything, I want to add a sense of lightheartedness to the group and contribute positively to this forum.

I also have found this group to be a bit more rough than other forums that I participate in. The G Series forum was great, but I'm always a little nervous to post something here. I think that part of the problem is that this forum includes lots of experts and also some of us who are just getting going. The experts are sick and tired of the same old questions asked by newbies and so it creates an environment which can be a bit hostile. Perhaps in the future they will find a way to have a separate forum for the lower end DSLR's.

Malok

My comments were not for you but were for Mr. Gross.

dear friends,
thanks for your comments and as I said, reading the details and information you get in this forum, I LOVE IT, and I do not think any book would detail the utility of mirror lock up as robertwgross did.
Robert, about your proposal, sorry but I just like the 10D and wanted to take advantage of its potential. otherwise, beleive me, I'd have trared it with even no extra cash.
regads
Khalid

robertwgross, that was truly enlightening... thank you. 8)

If they had been intended for me, then that is what private messages are for.

---Bob Gross---

Well, I had the very same question in my head back when I was a digital beginner, and my friend (an old pro) explained it to me.

Every camera is a little different and has a little different range of shutter speeds where mirror slap is worse. Further (I think) that the really high-end camera bodies have other gizmos around the mirror to soften the mirror slap vibration. For the rest of us with good, but not high-end, DSLR cameras, I guess we will just have to do the best we can.

---Bob Gross---

Hey Bob,

Most of the time I agree with what you say...however....this time I'm not so sure. The way I understand the sequence of events (mechanicals only, this does not include the light readings, TTL or ETTL sensing, etc.) is this:

1.) User presses shutter button

2) mirror flops up out of the way

3) lens stops down

4) shutter fires

5) lens stops back up

6) mirror flops back down

(two and three are actually simultaneous, or nearly so, as are 5 and 6.

Number 2 in the sequence is where the vibration we are concerned about is induced. The problem is that the camera may still be vibrating slightly for a half-second or so after the mirror flops up, which is during the time of the shutter firing at all shutter speeds. So, I would think that it would certainly affect the image at any shutter speed that is slower than about 1/500 or so where the shutter speed is fast enough to actually "freeze" the vibration. I know that's true with my Medium Format cameras...the mirror is like a darned earthquake on those things. I would think the sequence would be the same on a Drebel or 10D. The mirror has to be out of the way before the shutter fires.

Is my thinking screwed up here?

I know we agree on that much.

I know there are two slaps from the mirror. One is as it hits up, and the other is as it hits back down. Like we said, when it hits up, it vibrates for a split second. When it hits back down, it doesn't matter, because the shutter is closed by then.

"Anything faster (like 1/30), and the mirror slap happens after the end of the shutter, so it doesn't matter."

I went back and read my words. It seems better if I change it to read this way:

"Anything faster (like 1/30), and the mirror slap happens before the start of the shutter, so it doesn't matter."

How does that work?

---Bob Gross---

you guys became so "technical" and we're (myself and probably some fellas) get lost
with respect to professionals
khalid