Camera Labs

hey everyone...well i'm loving my new 10-20mm lens..but i've noticed that when i use my Xsi built in flash in low-light situations, or at night shots, there is a shadow in the bottom of the picture? I don't think its a lens problem...but is it just because the this Sigma lens is a beast and is so huge, that it blocks the built in flash when it fires, causing a shadow?

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who needs friends when you have a Rebel?

La Familia: Canon REBEL Xsi * EF-S IS 18-55 * Sigma 50mm f/1.4 EX DG * Sigma 10-20mm f/4-5.6 EX DC HSM * Canon 580EX II Speedlite E-TTL II * HOLGA 120CFN Medium Format Viewfinder * Velbon - El Carmagne 530
flickr

I think it might be a combination of obstruction, and maybe even the Sigma is such a wide angle the flash was never designed to light that wide. Remove the hood if you haven't done so already.

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Canon DSLRs: 7D, 5D2, 1D, 600D, 450D full spectrum, 300D IR mod
Lenses: EF 35/2, 50/1.8, 85/1.8, 135/2+SF, 28-80 V, 70-300L, 100-400L, TS-E 24/3.5L, MP-E 65, EF-S 15-85 IS
3rd party: Zeiss 2/50 makro, Samyang 8mm fisheye, Sigma 150 macro, 120-300 f/2.8 OS, Celestron 1325/13
Tinies: Sony HX9V.

Hi Avlis,

I do not think it's an issue with the lens either.

I have the "sister lens" from Tokina (the 11-16mm) on my D40 and the same thing happens. The lens has such a wide field of view that it can see it's own shadow.

A typical external flash in your hotshoe will probably be high enough to change the angle of the light so that this shadow will no longer appear even at 10mm.

Cheers

thx, popo and Lahlah...

well at least i know its just an obstruction problem and not a lens problem...so i guess i just g2 figure out the lens more so i don't keep getting the Sigma shadow...

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who needs friends when you have a Rebel?

La Familia: Canon REBEL Xsi * EF-S IS 18-55 * Sigma 50mm f/1.4 EX DG * Sigma 10-20mm f/4-5.6 EX DC HSM * Canon 580EX II Speedlite E-TTL II * HOLGA 120CFN Medium Format Viewfinder * Velbon - El Carmagne 530
flickr

It can be easily solved by avoidance of the pop-up and using an external flashgun.

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Nikonian

http://www.edtangphotography.com
http://journeysintophotography.blogspot.com/

I think the issue is that your 10mm wide angle is too wide for your lens. Like Photoj says, either avoid using your flash or get an external flash gun.

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PhilipGoh.com

Eh? Did you mean too wide for the pop-up? Surely a lens can't be too wide for its own good?

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Nikonian

http://www.edtangphotography.com
http://journeysintophotography.blogspot.com/

Duh! Too wide for the popup flash. I need to stop posting when I'm too tired.

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PhilipGoh.com

It's a problem with most wide-angles and even some kit lenses at their widest.

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Graham
Flickr

This result is normal with the pop-up flash at 10mm:


The other trick to avoid it (when shooting outside): turn the camera upside down so the shadow is projected into the sky

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Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews, My Pictures, My Photography Blog
D800+assorted lenses

Genius!

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Graham
Flickr