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Messages - neuroanatomist

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10276
Lenses / Re: Rumored 10 new lenses, 5 of which (CR) mentioned...
« on: March 10, 2012, 11:01:04 PM »
Could you please tell me a little more about the 70-300L being optimized for crop bodies? That's a lens I find interesting and I might even consider it... Thanks!


I'm not sure that Canon technicians said the 70-300L was optimized for crop bodies.  Nor is it in any way 'optimized' for APS-C in a technical sense - it's an L-series EF lens designed for FF sensors.  I think this stems from a Canon DLC article about the lens (basically a marketing piece), which points out that with the 1.6x crop factor the lens is like a 500mm lens on FF, thus it 'comes into its own' on APS-C.  In one way, I guess you could say it's a practical lens for 7D users - many of them have a 17-55mm, and the focus and zoom ring positions on the 70-300L match the 17-55mm (which is reversed from most L-series lenses).  Not sure if that was the reason for doing it, or (more likely) it was dictated by the optical design.

Still - it's an excellent lens on both formats, optically excellent, great build, weather sealed, and compact. 

10277
EOS Bodies - For Stills / Re: 5D3/5D2/D800 DR plotted
« on: March 10, 2012, 09:58:34 PM »
"There is no data yet for the D800E below ISO 200." From the page linked to.

Yet, they show a curve below 200.  I guess you would call that curve a creative estimate?

The graph is correct. The sentence you quote refers to ISO values, not their presentation on the graph.

Thus "ISO 400" is not below "ISO 200", it is above it.

"ISO 100" is below "ISO 200" and indeed is not present on the graph.

The D800 (purple line as you describe it) has data points (inverted triangles) at ISO 50 and ISO 100, for which there is no data according to the quote.  Not sure how you can state ISO 100 is indeed not present on the graph?

10278
Lenses / Re: Lens Calibration Help
« on: March 10, 2012, 09:44:26 PM »
Sounds like sending the lenses to Canon Service is the best option.  I agree that AFMA won't help in that case (on the 7D, at any rate - this sort of issue is why the 1D X and 5DIII store two AFMA values for zoom lenses).

10279
EOS Bodies / Re: 5D3 same max dynamic range as the 5D2???
« on: March 10, 2012, 08:24:45 PM »
This always begged the question in my mind: if you increase QE dramatically for a sensor without increasing full well capacity, don't you run the risk of blowing out the sensor for any given f-ratio & exposure combination compared to an older sensor with lower QE & same full well capacity? I realize that the increased QE sensor would have a lower gain for any f-ratio/exposure combination, but blown out is blown out... this always confused me.

Sure.  'Full well capacity' is measured in electrons, after conversion from photons. If QE goes up, you get more electrons per photons input, and the well fills faster.  It's probably not a practical problem, though, since in most normal shooting situations a lower gain (ISO) would solve the problem. 

10280
Lenses / Re: Group photo with 16-35 and Speedlite430
« on: March 10, 2012, 05:30:42 PM »
thanks everyone for your feedback.

I tried some shots last night.. couple questions.

1) when I shoot in auto mode... 1/60  F 4.0 ISO 1600 is the configuration shows up for the pictures .. when I set everything in Manual with exact same settings... the exposure indicator is around -3... which is not good...

When I lower the speed for the the correct exposure to 0 the speed is around 1/15 too slow... and pictures are over exposed... if I lower the ISO i have to further reduce the speed...

The pictures look just fine in auto mode or in M with the settings mentioned above....  so what is wrong with the exposure?

when we use flash (430) on camera do we still try to get correct exposure?


Nothing is wrong with the exposure.

If you're looking at the metering with the half-press of the shutter and the flash on, it will seem underexposed - the metering does not take into account the flash until you actually take the picture.  In other words, when you fully press the shutter, the flash will fire twice - the first, called the pre-flash, will be used for a combined metering of flash exposure and background, and the second will illimiunate the scene during the image (they're so close together that you often don't percieve separate flashes). 

With the flash on and Auto ISO selected, it will default to ISO 400, which is a good choice although you could use ISO 200 or 800 if you prefer to set the manually. 

What you're trying to do is balance the shutter speed to keep it high enough to freeze the people (meaning at least 1/60 s, preferably 1/100 s) but expose enough of the background to get some context.  If you use your max speed with flash (barring using of HSS, which isn't really needed/useful here), you're at 1/250 s.  In a typical indoor setting, that means almost all of the light for the exposure comes from the flash, so the edges of the scene may be a bit dark.  a wider aperture may help, too.   

Depending on the depth of field you need, and how far you are, f/2.8 might work if you're at 16mm.  For example, at 16mm f/2.8 on the 7D, if you're focused on a subjet 8 feet away, everything from 5 feet to 16 feet from your camera will be in focus - that's a reasonable DoF even at f/2.8.  You can estimate with a DoF calculator

I'd start with manual settings of ISO 400, f/4, 1/100 s and see how the histogram and scene look with a flash shot (remember - the flash will provide the light to make up for the underexposed ambient, it just won't be apparent until after the shot).

Definitely bounce the flash off the ceiling...but hopefully the ceiling is white, else you end up with a color cast in the shot.  If the ceiling is colored, head to a craft store for a large piece of white foam core, and have someone stand on a stool behind you and hold it over you at an angle, pointing the flash head up and back to bounce the light off the board (you'll have to play with the angles to get the positioning correct).

10281
EOS Bodies - For Stills / Re: 5D Mk. III user manual download -where?
« on: March 10, 2012, 04:52:33 PM »
Not that I've found, yet.

10282
EOS Bodies / Re: 5D3 same max dynamic range as the 5D2???
« on: March 10, 2012, 12:51:38 PM »
I started a thread one week before the 5DMkIII was launched, about the sensor technology (was it a fine tuning of the existing MkII model or something completely new):

My thread was simply deleted by the "administrator" after 5 minutes...

You can't obviously be too critical with Canon products on a site supporting the brand. If you want a more critical approach i guess you need to go on some other sites.

No, you can be quite critical here, that's not the issue.  What leads to threads being deleted is when they turn into a flame war instead of a civil discussion.

Also, there was a period a little before the 5DIII was announced when a bunch of people started threads of a very similar nature about the new model, and the mods went through and merged them into just a couple of threads to decrease clutter.  If you look at those threads (some run to 20 pages) you can see that the post titles jump around a lot because many threads were merged into one main one.  So, it's quite possible that your thread was not deleted, but simply 'disappeared' as a separate entity because it was merged with others.

10283
Lenses / Re: Rumored 10 new lenses, 5 of which (CR) mentioned...
« on: March 10, 2012, 12:42:19 PM »
How old is the 50mm 1.2 ? Isnt that due for an update?

2006, so not old by lens standards.  I don't expect an update any time soon...

10284
EOS Bodies / Re: i just had the x &tests the 5 in my hands
« on: March 10, 2012, 10:59:32 AM »
I think you'll be reincarnated as newt excrement unless you provide some details...    ;)

10285
Lenses / Re: Rumored 10 new lenses, 5 of which (CR) mentioned...
« on: March 10, 2012, 10:58:26 AM »
To clarify, the original TS-E lenses have tilt and shift fixed at a 90 degree orientation to each other. It can be changed, but to do so requires disassembling the lens.  The new L versions (17mm and 24mm II) allow altering the orientations of tilt and shift on-the-fly - and it's a great feature.

Ah, I only own the 90mm and wasn't aware of this feature.

I only own the TS-E 24mm f/3.5L II, but I use the rotation so frequently that I wouldn't even consider the 45mm or 90mm versions without it (90mm would be my preference - I can use the 2x Extender on the 24mm if I need ~45mm, and the optical performance is decent because the 24 II is so damn sharp to start with).

10286
Lenses / Re: Rumored 10 new lenses, 5 of which (CR) mentioned...
« on: March 10, 2012, 10:08:51 AM »
L-series versions of the TS-E 45mm and 90mm lenses.

+1 for the 90mm. That would make life complete.

In what way do find the 90mm lacking? Or do you just want the red ring?

To clarify, the original TS-E lenses have tilt and shift fixed at a 90 degree orientation to each other. It can be changed, but to do so requires disassembling the lens.  The new L versions (17mm and 24mm II) allow altering the orientations of tilt and shift on-the-fly - and it's a great feature.

10287
Lenses / Re: Canon L vs Zeiss ZE
« on: March 10, 2012, 10:04:50 AM »
Both are great. As some focal lengths, one is slightly better than the other, so it's lens dependent not a generalized difference.

Obviously, Zeiss lenses are manual focus only (but confirmation is available).  The body matters, too - manually focusing a fast prime with a standard focusing screen is challenging (you can't see the real DoF), so for example, I'd not get Zeiss lenses to use with the 5DIII since it doesn't have interchangeable focusing screens.

10288
Lenses / Re: Rumored 10 new lenses, 5 of which (CR) mentioned...
« on: March 10, 2012, 09:03:11 AM »
Old or not, it is just a top-notch lens.

I was thinking about the 135L again, and look at it another way. They made a lens, that great, 20-30 years ago.
Just imagine what they could do now, with better materials, better glass, most importantly better coatings, they already had fluorite back then but didn't use it, maybe they would in a II. Such a lens would have to improve on the current 135L, and if it did, it would be stunning...

I've got a 135L among my collection of L lenses, too, and it's an amazing lens.  But the above is exactly my point. - consider the change from the 70-200mm f/2.8L IS MkI to MkII, and extrapolate that to the 135L. 

10289
Lenses / Re: Rumored 10 new lenses, 5 of which (CR) mentioned...
« on: March 10, 2012, 08:14:01 AM »
135/2 is old, but is there anything wrong with it?

Exactly, Canon aren't going to replace a lens that can't be improved because its so great.  The only thing would be f1.8 or IS.  It's fairly lightweight and I just can't see them doing it.

What was 'wrong' with the 300mm f/2.8L IS or the 500mm f/4L IS?  Not a helluva lot.  But Canon would rather sell you the MkII versions costing 50% more.  If nothing else, the 135L lacks weather sealing.  But consider...Canon developed a zoom lens (70-200 II) that pretty much equals that excellent prime for IQ.  A prime should be better, and with modern design the 135L could be better.  A 135L II would not surprise me at all. 

10290
Lenses / Re: Rumored 10 new lenses, 5 of which (CR) mentioned...
« on: March 09, 2012, 11:23:47 PM »
L-series versions of the TS-E 45mm and 90mm lenses.

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