WR Photographics wrote:
Doesn't the mirror lock up in liveview? I'm pretty sure it does on my K1.

Yes, but you can use mirror lockup without using live-view, I guess I'm just wondering why you would do that, are there any advantages, are there other issues created by using live-view? (aside from lower battery life)

DespayreFX wrote:

Yes, but you can use mirror lockup without using live-view, I guess I'm just wondering why you would do that, are there any advantages, are there other issues created by using live-view? (aside from lower battery life)

Mirror lock-up is useful for long exposures on a tripod where the mirror might otherwise cause vibrations and some blurring.

DespayreFX wrote:
I've read conflicting reports, anyone have any actual experience of any difference between using live view, over using mirror lock-up?

Difference, in terms of image sharpness, I understand the usage difference.

Read

http://photo.net/canon-eos-digital-camera-forum/00ZwgQ

..It's the thread you'd have found doing the most obvious google search. Basically, with LV you focus on the sensor. How much more accurate this is than your primary focus system is (fairly obviously) dependent on your camera (and sometimes possibly  on where the focus point is.) With MLU you focus using the primary mechanism and pay whatever penalties your camera design imposes (low on a 5Diii, much higher on a 6D or 5Dii, etc.) These costs can also be dependent on the lens.

So no one can give you a simple "It costs you this much sharpness" without knowing at least the camera you are using.

(Oh - and then there may be other model dependent issues like whether your camera can electronic first curtain in live view. The simple rule is to use MLU for work like night photography and astro and Live View for accurate focusing on cheaper/older DSLRs.)

thiswayup wrote:
Read

http://photo.net/canon-eos-digital-camera-forum/00ZwgQ

..It's the thread you'd have found doing the most obvious google search.

Useless comment showing a complete lack of understanding about how the internet, Google in particular, works. Since I did do a search, and that didn't come up; it might help you to understand that the internet is global, and the results you get back will often not be the same as mine, the most simplistic and obvious understanding of Google would help you grasp that concept.

Further, if you bothered to read the question, (and yes, I realize, you were too excited that you might have an opportunity to make another ignorant comment, rather than focus on being helpful, and that prevented you from paying attention to the question) you would see that I found arguments claiming both sides of the argument, which is why I *specifically* asked if anyone had their own experience to share. But, like almost every other issue you comment on, you have no experience whatsoever with what you're talking about, but that doesn't stop you. You're welcome to continue pasting useless info into my threads, (apparently you're going to), but don't do it under the illusion that you're being helpful, because 90% of the time, at least in comments to me, you're not.

thiswayup wrote:
The simple rule is to use MLU for work like night photography and astro and Live View for accurate focusing on cheaper/older DSLRs.)

If you had just said this, that would have been helpful. Not a lot, since it's been said above by someone that's actually done it (which was specifically mentioned in the OP), but hey, baby-steps.

When are you going to post something to Critique? Show us your tax returns!

R.EYE.R wrote:
The only difference in IQ I can think of is that when the sensor is live, it tends to heat up and produce hot pixels and excess capture noise. As a result, you will lose more in high spatial frequencies (fine detail) rather than low (edge detail) - which type of detail is important to you is entirely your preference.

That's info I didn't have, thanks, hadn't considered heat as a possible problem. Interesting!

Ken Marcus Studios wrote:
Mirror lock-up is useful for long exposures on a tripod where the mirror might otherwise cause vibrations and some blurring.

Thanks Ken, that makes sense!

DespayreFX wrote:
Yes, but you can use mirror lockup without using live-view, I guess I'm just wondering why you would do that, are there any advantages, are there other issues created by using live-view? (aside from lower battery life)

Generally, if I am using MLU these days, I'm using live view as well. The camera I am using has a very good articulated screen that is very easy to use. Live view focus peaking goes a long way to ensuring that I have secured focus where I want.
A lot of my recent work has been pixel shifted focus stacks that can entail upwards of 40 exposures. Without focus peaking, it is very unhandy to ensure the focus is racking at increments that will ensure there are no soft spots in the final image.

I suspect that the advantages/disadvantages are going to be situational. I've found some situations that make using MLU and liveview combined incredibly useful.