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11/17/2011 11:34:56 AM · #1
12 photography myths every photographer should know

Found this quite interesting.
11/17/2011 11:41:12 AM · #2
Myths 6 (mirror lock up) and 7 (repeated JPEG saving) are the most surprising to me.
11/17/2011 12:04:23 PM · #3
I was surprised about how the "sweet spot" of the 50mm was at 7.1??? wow.
11/17/2011 12:11:30 PM · #4
Originally posted by lawrysimm:

Myths 6 (mirror lock up) and 7 (repeated JPEG saving) are the most surprising to me.


Take what he says with a grain of salt. He tested himself, under a limited set of conditions, and then drew general conclusions from specific results :-P
With regard to mirror lockup, I can attest that it can and does make a difference. It does not make a perceptible difference in all situations, though. The key is knowing when it is worth the extra time.
With regard to repeated saving of JPEGs, he tested only at Ps's highest quality setting. That is very nearly a lossless save, and his results make perfect sense. Try that on a lower quality setting, and the results will be quite different. I do agree, though, that the impact for everyday images and a reasonable number of re-saves (maybe four to six?) is minimal.

Message edited by author 2011-11-17 12:12:05.
11/17/2011 12:18:24 PM · #5
Originally posted by lawrysimm:

Myths 6 (mirror lock up) and 7 (repeated JPEG saving) are the most surprising to me.


+1
11/17/2011 12:27:44 PM · #6
He tested mirror lockup on "long exposures" and found no evidence that it helps. I agree with that. It's the middling exposures where it matters; like, say, 1/8 sec or 1/4 sec, somewhere in that range. On truly long exposures, say 5 seconds plus, lockup is utterly pointless.

R.
11/17/2011 12:55:05 PM · #7
Originally posted by Bear_Music:

On truly long exposures, say 5 seconds plus, lockup is utterly pointless.

Mind expanding on why that is... just trying to understand.

Is it because the slight initial movement from the mirror slap is such a small part of the full exposure that it's irrelevant in the image - whereas a middle time it's a longer percentage of the full exposure??

Would that not change with something like - dunno - fireworks maybe where most of the light is in the initial hit and the longer trail is just taking in smaller background light?
11/17/2011 01:08:24 PM · #8
I completely agree with Robert. Unless the mount is horribly shaky, mirror vibration typically damps out in under 1/10 second. Exposures that are in this range will show the most degradation, while those that are much longer will show less. One caveat: if there are very bright point light sources in the frame, the effects of mirror slap can sometimes still be seen on longer exposures, as a dim trail. You don't often see this though, and when you do you normally need to be looking for it.
11/17/2011 01:54:22 PM · #9
Originally posted by kirbic:

I completely agree with Robert. Unless the mount is horribly shaky, mirror vibration typically damps out in under 1/10 second. Exposures that are in this range will show the most degradation, while those that are much longer will show less. One caveat: if there are very bright point light sources in the frame, the effects of mirror slap can sometimes still be seen on longer exposures, as a dim trail. You don't often see this though, and when you do you normally need to be looking for it.


Affirmative. As for fireworks, consider that mirror slap is meaningless when strobes are used, as they are instantaneous. Ditto for fireworks bursts, they are strobe like. The moving trails of fireworks, well, they are moving, right? So mirror slap will be meaningless there as well.

The one reason I might encourage you to use mirror lockup when shooting fireworks is a curious one: obviously, with the mirror locked up, you can't use the viewfinder, and this forces you to view the scene more organically or experientially, which can only benefit you in your quest for the perfect window of exposure, compositionally.

R.
11/17/2011 02:02:54 PM · #10
Originally posted by Bear_Music:

The moving trails of fireworks, well, they are moving, right? So mirror slap will be meaningless there as well.

Trails at right-angles to the direction of the mirror-induced vibration should show a slight offset (like a classic lighting stroke image), while those running in the same direction shoulf not.

But I think if you're going to the trouble of looking for that instead of appreciating the fireworks ... :-(

Also, I've been given to understand that with PS CS 3 or so, the highest-level JPEG was now actually lossless, though I don't understand why one would save an image for later editing in anything other than .PSD (has it's own lossless compression built-in) or TIFF (with lossless LZW compression if desired).

Maybe I'm spoiled by still working with relatively small images, but I don't use compression at all except to get challenge entries under the limit, or when saving at maximum quality JPEG for printing where they don't take TIFFs.
11/17/2011 02:19:42 PM · #11
As an alternative to tupperware, which can be quite expensive by itself, I bought a flash diffuser off of Amazon for $0.01! That's right. A penny. $2.99 shipping, for a grand total of $3.00. LOL!

link

Message edited by author 2011-11-17 14:20:05.
11/17/2011 02:55:40 PM · #12
Originally posted by Kelli:

A penny. $2.99 shipping, for a grand total of $3.00. LOL!

I've always hated the shipping-to-actual price ratio, but that's ridiculous.

BTW, someone now has it for $2.37 + $0.50 shipping for a $2.87 total ... now if we could only get the one cent sale price together with the fifty cent shipping ...
11/17/2011 03:35:55 PM · #13
Originally posted by GeneralE:

Originally posted by Bear_Music:

The moving trails of fireworks, well, they are moving, right? So mirror slap will be meaningless there as well.

Trails at right-angles to the direction of the mirror-induced vibration should show a slight offset (like a classic lighting stroke image), while those running in the same direction shoulf not.

But I think if you're going to the trouble of looking for that instead of appreciating the fireworks ... :-(


Yep, what Paul said. Since the point source is tracing a line across the sensor, vibration perpendicular to that direction will make the line "wiggle." In fact, you could use this effect to "map" the damping of the mirror-induced shake. It's one of those special cases where mirror slap may actually be observable on long exposures. When all is said and done, though it's actually going to be hard to find this phenomenon.

Originally posted by GeneralE:

Also, I've been given to understand that with PS CS 3 or so, the highest-level JPEG was now actually lossless...


That was my understanding as well.
11/17/2011 04:02:34 PM · #14
I was under the impression that mirror lock-up was only really usefull for macro shots where you were going after extreme detail.
11/17/2011 04:07:13 PM · #15
Originally posted by dswann:

I was under the impression that mirror lock-up was only really usefull for macro shots where you were going after extreme detail.

I always use mirror lock-up. I create the exposure by covering the lens with my hand, and allowing light in for a more precise amount of time than mechanisms are capable of. However, I know secret Ninja moves from the government.
11/17/2011 04:20:38 PM · #16
Originally posted by Strikeslip:

However, I know secret Ninja moves from the government.


Yeah, but they're Canadian Ninja moves
11/17/2011 04:29:57 PM · #17
Originally posted by Spork99:

Originally posted by Strikeslip:

However, I know secret Ninja moves from the government.


Yeah, but they're Canadian Ninja moves


LOL, visions of Red Green!
11/17/2011 04:33:56 PM · #18
Originally posted by dswann:

I was under the impression that mirror lock-up was only really usefull for macro shots where you were going after extreme detail.


Oh no. I often use mirror lockup with a remote release for tripod-based landscape work. It's really very little more work.
11/17/2011 04:34:15 PM · #19
Originally posted by kirbic:

Originally posted by Spork99:

Originally posted by Strikeslip:

However, I know secret Ninja moves from the government.

Yeah, but they're Canadian Ninja moves

LOL, visions of Red Green!

When I take a shot, my camera is silent, but I yell "WHATCHAAAA!"
11/17/2011 04:48:15 PM · #20
I see that site didn't dispel the secret camera setting Canon's and Nikon's have that make all your photos instant ribbon winners... I'll keep searching.
11/17/2011 05:04:26 PM · #21
Originally posted by Strikeslip:

Originally posted by kirbic:

Originally posted by Spork99:

Originally posted by Strikeslip:

However, I know secret Ninja moves from the government.

Yeah, but they're Canadian Ninja moves

LOL, visions of Red Green!

When I take a shot, my camera is silent, but I yell "WHATCHAAAA!"


Doesn't that scare the squirrels?
11/17/2011 06:11:20 PM · #22
As for the JPG Vs. Raw white balance point, based on my experience in case of massively wrong WB (e.g. fluorescent in daylight) the RAW has a considerable edge, as different colours often will be remapped to the same one in JPG thus loosing them irreparably.
However, it might be a problem with my postprocessing skills.
11/17/2011 07:12:17 PM · #23
Originally posted by mcaldo:

As for the JPG Vs. Raw white balance point, based on my experience in case of massively wrong WB (e.g. fluorescent in daylight) the RAW has a considerable edge, as different colours often will be remapped to the same one in JPG thus loosing them irreparably.
However, it might be a problem with my postprocessing skills.


Oh, it's not. Your skills, that is. He does have a point, you can certainly correct the WB in a JPEG, but there is significantly less latitude in doing so before the fact that strong adjustments have been done becomes apparent.

Message edited by author 2011-11-17 19:12:39.
11/17/2011 07:25:06 PM · #24
Uh, actually that's what I meant too. Raw has an edge on JPG when correcting WB, and this is particularly true, in my experience, when correcting extreme WB shifts.
Sorry, probably it's my english and my devious way of putting phrases together :)
11/19/2011 02:37:40 AM · #25
thanks you for your information
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