Messages

1

Lenses / Re: Tamron 24-70 f/2.8 or Canon 24-105 f/4

« on: January 04, 2013, 03:24:51 PM »

As an owner of the 5D3/Tamron 24-70 combo, I would tend to speak highly of the performance.  For low light shooting I think you would find the faster lens extremely valuable.  I don't find the VC to be as effective as the IS in my 70-200/2.8 IS II, but it still has value.  Sharpness I find plenty acceptable, though I don't tend to judge my shots down to a 100% level.

As some reviews have mentioned, it is a little shorter than 70mm on the tele end.  I have read around 65mm and that seems about right when comparing it to my 70-200.  There are times where I wish it had just a bit more reach, certainly.

In terms of build quality, I find the 24-70 quite nice.  I have also had the opportunity to [briefly] handle the 24-105 and I prefer the feel of the Tamron.  I don't know about the level of "weather-sealing" to the Tamron lens.  I did notice a rubber seal in the area of the lens mount, which would lead me to believe it has some level of weather sealing. 

Brian

2

5D MK III Sample Images / Re: Wedding Photography Photos - 5d MK III

« on: November 13, 2012, 04:18:45 PM »

70-200 F2.8L IS II

3

5D MK III Sample Images / Re: 5DIII Exposure difference from Lens to Lens with Speedlite

« on: November 02, 2012, 12:08:52 PM »

i wonder about the Sigma's ability to relate TTL info to the flash if you were in fact in TTL mode on your flash. i am not positive about how TTL info is gathered and communicated but because of this i would do 2 additional tests:

1. shoot a canon 85mm (if you can get your hands on one) with the sigma 85mm just as you did with the 70-200 and see if the same problem occurs
2. shoot the same test again in manual flash mode with the sigma 85mm and canon 70-200mm (this should yield the exact same results...if it doesnt something is terribly wrong)

also, have you repeated the original test and gotten similar results? if not i would do it again just to see if it was a fluke. sometimes there are connection issues with my canon flashes on canon bodies that cause the flash to go out of TTL mode and default to manual flash power at full power. if i take the flash off and put it back on the camera it will then recognize TTL communication again.

This is certainly a repeatable event.  I would say I switched back and forth between lenses 5-6 times and had the same situation happen each time.

I took a brief gap at lunch to try setting the *flash* (originally said "camera") in manual mode.  I can't be certain that this would have fixed the issue last night, as the lighting in my living room is now drastically different.  But it did result in similar exposures, lens-to-lens, with the same settings.  This seems to indicate to me that the flash is firing with less power when the zoom is attached compared to when the prime is attached when in E-TTL mode.

I did note that my settings in the camera were "evaluative" metering for flash, as opposed to average.  Not sure if this will make a substantial difference. 

Thanks all for weighing in.  I will continue to experiment with different settings.  If need be, the flash can just be operated in manual mode

Brian

4

5D MK III Sample Images / Re: 5DIII Exposure difference from Lens to Lens with Speedlite

« on: November 02, 2012, 08:19:53 AM »

The issue is the distance from the flash to the subject. I use a similar flash unit - the Yongnuo 565 - which has a similar guide number (GN), and is a very powerful flash. Each flashgun has a minimum power output and if your aperture is too big (in this case f2,8) and your ISO too high (ISO=400 in your shots, I would've used ISO=160 in your 2nd shot), then the flash unit cannot reduce the power output enough to match the chosen aperture, so your 2nd shot is over-exposed. Personally, I would have chosen ISO=640 for the zoom lens and ISO=160 for the prime, or alternatively, you could have stopped down your 85mm to f4 and that would have halved the reflected light.

You could also try taking the flash off-camera and/or bouncing the flash off the ceiling - by the looks of your 2nd shot the flash head was directed at your subject's forehead - the skin above his right eye is blown-out, almost no detail, which is why I think it looks overexposed. Trigger the flash remotely and lens choice will no longer adversely affect your exposure.

Both images were taken the same distance from the subject, and I attempted to set the zoom at 85mm (this obviously didn't happen exactly, as the framing is slightly tighter with the zoom).  The flash was bounced directly off my ceiling which is ~12' tall and a just off-white color.  You seem to get to the point of my question in that: The lens can make a difference, even when the aperture is the same in both cases? Shooting the zoom wide open at f2.8 and stopping down the prime to f2.8 can still result in different exposures?

What mode were you shooting in? Manual? Aperture?

The lens hood should make no difference - I always shoot with mine on...

Have you enabled the external speedlite in the menu system?

I am not familiar with Yongnuo - but my 430EXII is VERY finicky with my 5DIII - when the flash is the primary light source the exposures are perfect - but fill-flash is all over the place...

Yes, you definitely want to nail this down before you shoot a wedding!

These shots were done in manual so that I could be certain the shutter speed/aperture/iso/etc were all the same from one picture to the next.  Yes, I have enabled the speedlite in the menu system.

Fortunately i'll be just doing this wedding for fun, as i'll also be participating.  But it would be nice to know for the next event/wedding that roles around.

Thank you both for the quick replys.  Hopefully I can make sense of this soon.

Brian

5

5D MK III Sample Images / 5DIII Exposure difference from Lens to Lens with Speedlite

« on: November 01, 2012, 09:23:50 PM »

Recently I upgraded from a 7D to a 5D mark III.  With the new body I also purchased a 70-200 f2.8L IS II.  This combo has worked quite well for me through a couple events so far.  But, as I am preparing for a (family) wedding this weekend, I noticed a weird trend.  Attached you will find two pictures, no time was spent on them, they are out of camera, and they were just to show the exposure difference.  Both pictures were taken at 1/100, f2.8, FC:0, iso 400. The first was taken with the 70-200.  The second, with my Sigma 85 f1.4.  As can be seen, there is a large difference in the exposure from shot to shot.  I should also note that the speedlite used was a Yongnuo YN-568 (batteries were fully charged in both instances)

This is the first zoom that I have spent much time using, especially with a speedlite.  Before I relied predominantly on my 50/1.4, 85/1.4, and 100 Macro. 

Can anyone lend any guidance as to why I am having such variance in exposure?  I though it may be due to the length of the lens, my first attempt was to take the lens hood off.  This seemed to have no significant effect.

Perhaps it is something easy that I am missing.  Forgive me if this is the case.  I am still relatively new with photography.  If its just a trait of using the long zoom with a speedlite then that is something I can adjust to.  By increasing the FC on my speelight to ~+3 I can get a similar exposure to the prime lens.