550 ex OR Sigma Super DG 500

Everything comparing the two contains the same basic statment...Sigma is comperable to the 550 but it is half the price!

Well it is no longer half the price...Seems to me the new sigma is about $230 and a used 550 is about $250.

Sooo....How do they stack up now!

I understand there are some differances between the two, but they seem to be minute and overcomable by gadgetry.

I have done a ton of reading (I actually am starting to even comprehend part of it) and have a high regard for knowledgable input from many of our esteemed members here.

Given the current marketplace due consideration, witch of the two or heaven forbid a third choice (a ton more reading) would you choose.

Off camera usage is a feature I would like to learn to utalize. seems the sigma would have the edge here ( Maybe)

neumanns wrote in post #2992110
Off camera usage is a feature I would like to learn to utalize. seems the sigma would have the edge here ( Maybe)

Depends on how you want to go about it.

If you want to follow the Strobist philosophy of manually adjusted off-camera flash, the Sigma's built-in optical slave is a real bonus.

If you want E-TTL control with ratios in a wireless multi-flash setup, then Canon's system is better than Sigma's. But you'll need a second Canon Speedlite capable of E-TTL slave function if you want to go that route.

The optical slave mode of the Sigma is a great feature that I use often. Beyond that I think the 550EX is probably a better built unit.

You can get a new Sigma 500 Super for under $200 from sigma4less.com and it will come with a warranty that the used 550 will lack.

Otherwise, Curtis already hit the biggest differences.

Curtis...That is pretty much the conclusion I have come to also, That is why I asked the question.
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.And Here I was hoping you were gonna give me some great kernal of knowledge that was gonna be a clearvoiant moment...........I'm still waiting! (All in fun of course )

Hmm...Leaning towards sigma, since right now it is gonna be a one flash setup with the on camera as trigger..........Oh to be rich!

Mbellot...Yeah I was aware of that, I just went with the 230 because it seems to be what the market price is but that is in all liklehood where I would order it from.

neumanns wrote in post #2994910
it is gonna be a one flash setup with the on camera as trigger.

Trying to use the camera's built-in flash to trigger an optical slave would be an excersize in frustration, since the E-TTL pre-flash will trigger the slave prematurely. To use an optical slave, you'll need a manual or old-fashioned automatic flash on the hotshoe.

(Canon does not make it easy or cheap to use off-camera flash.)

I had the same problem myself Sigma or Canon.
I went for the Sigma and saved loads of money.

My friend bought the Canon and the results are just the same. The recharge time on the Canon is a little faster and you get a bounce card, but you could make a better one.

The off-camera optical slave on the Sigma is a cool bonus.

If you got money to burn buy the Canon.
If not buy the Sigma.

Dosent shooting in M or AV overcome this?

neumanns wrote in post #2995098
Dosent shooting in M or AV overcome this?

Nope. The built-in flash has no manual mode and always fires a pre-flash.

You can work around it buy using the FEL button to fire the preflash, then wait for the slaves to recycle and take your shot. But I sure wouldn't buy a slave with this plan in mind.

I don't think this is the case on the Xti...but I could be wrong. (high probability)

neumanns wrote in post #2995319
I don't think this is the case on the Xti...but I could be wrong. (high probability)

Take a shot with flash while looking through the viewfinder and keeping your left eye closed.

If you see a flash through the viewfinder, it's the pre-flash. The "real" flash happens when the mirror is up and the viewfinder goes black.

I think the key is AI servo...Under oneshot it fires a focus assist/ettl preflash but under AI Servo I believe it does not.

Under ai servo I can fire a focus assist/ettl evaluative via the focus/fel lock button.

I tried the viewfinder left eye deal but I find it hard to confirm ...there seems to be some light but it may just be the mirror catching it at top stroke.

If there is a preflash/second flash they are within milliseconds.

Hmm wonder how we can confirm this seeins as I don't have your knowledge and you dont have an xti!

I called canon tech support...They tell me in Ai servo, Tv AV M does not fire a preflash, I forgot to ask about P but I think it is the same there also.

I understand just because tech support say's dosent nessacerly confirm it.

But if this is the case then via the onboard with FEC and sigma off camera it should give me decent lattitude with a "one flash" solution provided I can expirment with the off camera flash incraments and placment.

neumanns wrote in post #2995518
Under oneshot it fires a focus assist/ettl preflash but under AI Servo I believe it does not. Under ai servo I can fire a focus assist/ettl evaluative via the focus/fel lock button.

neumanns wrote in post #2995650
I called canon tech support...They tell me in Ai servo, Tv AV M does not fire a preflash.

It's important to understand that the AF assist light and the E-TTL pre-flash are two different things. In AI Servo you won't get the AF assist but when you take a shot it will still use a pre-flash. And yes, the pre-flash and real flash happen milliseconds apart.

Regardless of AF mode, you can use the FEL button to fire the pre-flash, then take the shot as I described earlier.