Mirror Lock....or not?

CyberDyneSystems wrote in post #4121014
MLU is hugely helpful on long telephoto shots.. I don;t care what the article says the proof is in the shots.

Indeed - I've taken hundreds of moon images with tripod (and a few without). Given that my final crops and prints are often close to 50% crops, MLU is very useful even at shutter speeds where the "rules of thumb" claim it shouldn't be necessary. The difference is very apparent at that level of enlargement, especially if the tripod is strained and prone to vibration (like my old setup was with a heavy lens).

jrsforums wrote in post #4121115
Is that "long lens" of "long time"?

The first premis is if the article is correct, which it seems to be, that the mirror slap viabration is damped within ~1/60 sec. due to mass of camera, lens, and tripod.

Not always true - I've had setups that took 5+ seconds for vibration to dampen out.

Then....if you have a 5 second exposure, it would seem logical that any viabration occuring in the 1/60 would have no chance of being recorded vs. the other 299/60ths.

The key here is that the article documents the premis they make. I have not seen and documention of long exposures where using MLU did make a difference....usually it is "hearsay"....or "I don't care....I'm gonna do what I do" ( not your words...mine).

The important point is that the image quality-degrading effects of mirror-induced vibration are typically minimized by both faster and longer exposures. Though, other factors such as lens and fl used, mass of equipment, etc. will influence.

On a shaky mount (see my previous post), even a 5 second exposure can benefit from MLU. On more stable mounts, perhaps not. But a 1/125 second exposure with an 800 mm lens presents a very, very sensitive situation. You will see blur even if the vibration dampens in 1/250 of a second.

MLU does not expose the sensor - just the shutter curtains. Precautions should be taken when exposing to intense light sources such as the sun as the heat can damage the shutter curtains in a fairly short time. But note that when shooting images of the sun (don't look through the viewfinder without eye protection), your shutter speeds will be very high, generally negating the need for MLU. Unless an extremely strong ND filter is used, of course.

Speaking of MLU, the arrangement on my hacked 300D uses the timer to actuate the shutter. I push the button and the mirror goes up, then 3 seconds later the shutter operates.

Is this the way more modern DSLRs work? I've seen references to pushing the shutter button twice...

-js

number six wrote in post #4123790
Speaking of MLU, the arrangement on my hacked 300D uses the timer to actuate the shutter. I push the button and the mirror goes up, then 3 seconds later the shutter operates.

Is this the way more modern DSLRs work? I've seen references to pushing the shutter button twice...

-js

On my 30D, I use a remote; first button press flips up the mirror.

I wait a few seconds.

Essentially you're doing the same thing.

Second button press actuates the shutter.

And now to stir the pot:

http://markins.com/cha​rlie/report4e6.pdf

number six wrote in post #4123790
Speaking of MLU, the arrangement on my hacked 300D uses the timer to actuate the shutter. I push the button and the mirror goes up, then 3 seconds later the shutter operates.

Is this the way more modern DSLRs work? I've seen references to pushing the shutter button twice...

-js

Push the shutter button twice, once to lock up the mirror, second to release the shutter. This is the preferred method with a remote.

If you don't have a remote, set mirror lockup, and then use the camera's timer. You'll get the result that you have above. Or at least that's how it works on my XTi.

Tom W wrote in post #4124036
Push the shutter button twice, once to lock up the mirror, second to release the shutter. This is the preferred method with a remote.

If you don't have a remote, set mirror lockup, and then use the camera's timer. You'll get the result that you have above. Or at least that's how it works on my XTi.

Ummm, with the stock 300D there is no "preferred" mirror lockup method. It can't be done.

I like the hacked approach - one touch, then the timer...

-js

number six wrote in post #4125040
Ummm, with the stock 300D there is no "preferred" mirror lockup method. It can't be done.

I like the hacked approach - one touch, then the timer...

-js

Not familiar with the stock 300D, but the hacked model apparently performs like the rest of the Canon Rebel series. I didn't realize that MLU wasn't an option. No wonder everybody was hacking them.

I had a post similar to this where a photographer giving a course said using MLU even on his 600 nikon improved the IQ by ten times.

I know that is an exaggeration, but I am still undecided on whether to use it with my 500 with 1.4 and mark III.

Does anyone have any tests proving what is best MLU of not MLU ?

especially in regards to long lenses with decent 1/500 + shutter speed.

When shooting the moon at 300mm with a 2X teleconverter and 1.6 crop factor at f11 and 1/200 sec (give or take a stop or two depending on ISO and light), I found that there was no contest -- MLU was absolutely necessary for a blur free image. Non-MLU shots were a complete loss even at 4X6 print sizes.

number six wrote in post #4125040
Ummm, with the stock 300D there is no "preferred" mirror lockup method. It can't be done.

I like the hacked approach - one touch, then the timer...

-js

The 10D actually had that as it's MLU default if I recall correctly... of course this makes sense as most of the 300D firmware hack came from the 10D's firmware (of not all)

When I'm shooting landscapes, unless I'm in bright daylight, I figure MLU goes hand-in-hand with a good tripod and a cable release. Of course I could hand-hold and open the aperture a bit and hope for the best, but I would rather give myself the best chance of the most good shots. It certainly doesn't hurt. And, I haven't been disappointed.

Doing wildlife, though, I don't use MLU, and often don't use a cable release (depending on the lighting) and sometimes will even hand-hold with a long lens, simply because I have the aperture open enough to allow for faster shutter speeds.

I don't do a lot of longer exposure stuff -- some low-light macro, some low-light landscapes, but I do tend to use MLU for such uses...why not?

Tony

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Several Canon cameras, too many lenses and stuff to list

Tony Long Photos on PBase