Originally Posted by
William W
Thanks. Understood.
I would take the 17 to 70/2.8.
You probably know this – but anyway: That particular Sigma Lens is “designed” to work (only) on a Canon APS-C Camera (i.e. it throws an APS-C sized Image Circle).
However, it has a Canon “EF” Lens Mount. This is a point worthy of note about third party lenses designed for use on Canon APS-C Cameras: that is - unlike the Canon EF-S Lenses, third party lenses from Tokina, Sigma and Tamron all have a Canon ‘EF’ Bayonet Mount, which means that they can be mounted and used on all canon EOS Cameras. Therefore (taking your situation as an example) in a emergency you could use the 17 to 70/2.8 on the 6D.
Just something for you to think about: now that I know that you have a fast zoom for the 550D and an IS zoom for the 6D, I probably would just use the two zoom lenses and take the 50/1.8 as the third tier backup.
I’ve used the 24 to 105/4L on a 5D and pumped out good to very good 10x8 print quality at ISO “H” (aka 3200) – so I would be happy as a bat in a cave in low light and shooting sans flash with a 6D’s sensor. I’d keep the 50/1.8 in my pocket and pull it out only if the environ was so dark to make F/4 too slow for an ‘appropriate’ ISO choice.
I’d just use the Flash on the 550D and 17 to 70/2.8 rig or use the flash off camera held by your assistant – though I do think off camera flash is a big ask, if you want to “keep it simple.”
I’d work with two cameras slung on me.
The idea of working two cameras might be too much to consider on your first date, but that set up is worth mentioning to you, especially if you are reasonably competent in Available Light with your 6D and the 24 to 105/4L IS Lens.
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OK.
Follows is an explanation of what you did not understand.
You asked:
I answered:
The first paragraph in my answer is referring to the options that you have to control the selection the shutter speed when the camera is in Av Mode and a Flash is Active.
The NAME of that functionality is ‘Flash Synchronization in Av Mode’ and you access that functionality and choose the setting that you want, via the camera’s menu system
However, that functionality will NOT be available to you unless the camera RECOGNIZES that a Flash is ACTIVE on the Hot-shoe. Most probably, if the flash fires: then the camera does recognize that there is a flash active – BUT I WOULD NOT BET A MARS BAR ON IT.
Testing the Flash only confirms that the Flash Fires and does NOT confirm that the ‘Flash Synchronization in Av Mode’ is working correctly.
What I would do is TEST the functionality (of ‘Flash Synchronization in Av Mode’) in ALL THREE of the options - with the flash on the Hot-shoe and turned on and CONFIRM that the camera is limiting the shutter speeds as you expect it so to do in each of those three selections.
Of course if you choose not to use Av Mode with the Nissan Flash, then doing such a test is irrelevant: I was only alerting you to pitfalls – for example IF you think that you have limited the shutter speed to a certain range and in fact you have not – then you might have a few surprises.
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The points made about the expectations of the Bride and the Mother of the Bride irrespective of what your understanding is with the Groom, are all, most relevant.
I wish you good luck with it.
WW