Some Comments on Sigma 50-500mm Lens

[Hobbes234]

hi, guys.

have some questions. wat is the difference if you use a lower zoom lens like 70-200mm and a tele convertor (2.0X) compared to a lens like 50-500mm.

newbie to lenses.
kindly enlighten

regards

 

[tomshen]

Originally posted by sfhuang
Tom, a bit OT here but why did you use evaluative metering at -1/3?

Thanks.
sfhuang

Background. If metering at 0, the fur would have been overexposed due to darker background. The fill-in flash was just to add some catch light in the eyes. The key to this shot was:
1. The subject must have a distance from the background.
2. The background must be a uniform texture, preferrably sand/rock/grass.
3. 500mm (800mm equivalent) close-up to eliminate any distracting background and foreground.
4. f5.6 or above. Otherwise DOF may not be enough.
5. Be patient. Cable release is strongly recommended due to slow shutter speed (for dark environment).

 

[TME]

Originally posted by tomshen
Background. If metering at 0, the fur would have been overexposed due to darker background. The fill-in flash was just to add some catch light in the eyes. The key to this shot was:
1. The subject must have a distance from the background.
2. The background must be a uniform texture, preferrably sand/rock/grass.
3. 500mm (800mm equivalent) close-up to eliminate any distracting background and foreground.
4. f5.6 or above. Otherwise DOF may not be enough.
5. Be patient. Cable release is strongly recommended due to slow shutter speed (for dark environment).

So u deliberately underexposed to ensure that the fur came out the right brightness while the flash took care of the eyes.... care to explain why u compensated for the flash as well with 1.3EV?

Usually I just spot meter on the fur or eyes or sync flash..... how much difference does this make compared to what u did? Could u do a guesstimate for me? Thanks!

 

[TME]

Originally posted by Hobbes234
hi, guys.

have some questions. wat is the difference if you use a lower zoom lens like 70-200mm and a tele convertor (2.0X) compared to a lens like 50-500mm.

newbie to lenses.
kindly enlighten

regards

I'm not sure but I think it has to do with the quality. With a teleconvertor, u have more glass and that increases all sorts of distortions from chromatic abberations to vertical istortions to goodness know what else.... but using TCs are a cheap way to extend your range without having to buy a new lens.... downside is as above and perhaps finding a suitable TC for that matter....... please correct me if I am wrong... cos I'm still a novice.......

 

[sfhuang]

Originally posted by tomshen
Background. If metering at 0, the fur would have been overexposed due to darker background. The fill-in flash was just to add some catch light in the eyes. The key to this shot was:
1. The subject must have a distance from the background.
2. The background must be a uniform texture, preferrably sand/rock/grass.
3. 500mm (800mm equivalent) close-up to eliminate any distracting background and foreground.
4. f5.6 or above. Otherwise DOF may not be enough.
5. Be patient. Cable release is strongly recommended due to slow shutter speed (for dark environment).

thanks tom! This is very useful info. :thumbsup:

 

[tomshen]

Originally posted by TME
So u deliberately underexposed to ensure that the fur came out the right brightness while the flash took care of the eyes.... care to explain why u compensated for the flash as well with 1.3EV?

Usually I just spot meter on the fur or eyes or sync flash..... how much difference does this make compared to what u did? Could u do a guesstimate for me? Thanks!

Nope, I did not underexpose the fur. The black background made the aperture wider open. Without -1/3 exposure compensation, the fur will be overexposed. BTW, flash compensation is -1.3, not 1.3. Normally -1 in fill-in mode. For darker background, an additional -0.3 is better. The background is not totally dark and the meerkat's fur is close to mid-tone, so no further exposure compensation is required. Spot metering is useful, but I don't have time to do spot meter. Usually fix the tripod and wait, with cable release.

 

[akdwivedi]

wow... I am impressed... think i should buy the lens... Anyone selling this lens..

Also any issues of compatibility of this lens with EOS 1V, EOS D30/D60/10D..

cheers

 

[TME]

Originally posted by tomshen
Nope, I did not underexpose the fur. The black background made the aperture wider open. Without -1/3 exposure compensation, the fur will be overexposed. BTW, flash compensation is -1.3, not 1.3. Normally -1 in fill-in mode. For darker background, an additional -0.3 is better. The background is not totally dark and the meerkat's fur is close to mid-tone, so no further exposure compensation is required. Spot metering is useful, but I don't have time to do spot meter. Usually fix the tripod and wait, with cable release.

So am I right tosay that the flash compensation is to only lighjt up the eyes and at -1.3EV, it does not ruin the exposure for the fur as well, which u have already stopped down to prevent overexposure in the first place? Thans! Cos I dun really get the reason for having flash compensation on my Dynax 7... kekeke as I say I'm a novice..... thanks a lot!

 

[TME]

Originally posted by tomshen
Nope, I did not underexpose the fur. The black background made the aperture wider open. Without -1/3 exposure compensation, the fur will be overexposed. BTW, flash compensation is -1.3, not 1.3. Normally -1 in fill-in mode. For darker background, an additional -0.3 is better. The background is not totally dark and the meerkat's fur is close to mid-tone, so no further exposure compensation is required. Spot metering is useful, but I don't have time to do spot meter. Usually fix the tripod and wait, with cable release.

Sorry another question... when u say fill-in is usualy -1EV, are u saying that u manually set it such or that the camera atuomatically does a -1EV for the flash when u just shoot with flash? Cos I thought fill-in flash means that u just switch on the fklash (external or built-in) and then fire away with the TTL metering taking care of the exposure?

 

[tomshen]

Originally posted by TME
Sorry another question... when u say fill-in is usualy -1EV, are u saying that u manually set it such or that the camera atuomatically does a -1EV for the flash when u just shoot with flash? Cos I thought fill-in flash means that u just switch on the fklash (external or built-in) and then fire away with the TTL metering taking care of the exposure?

Set manually. More than just resulting in some sparks in the eyes, the fill-in flash also removes some shadows.

 

[TME]

Originally posted by tomshen
Set manually. More than just resulting in some sparks in the eyes, the fill-in flash also removes some shadows.

Yeah that's right...... thanks!