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Marlton Mom
06-02-2011, 10:31 PM
I have a question about flash settings.

For the Nikon SB 700 in Slow Sync + Rear Curtain mode the flash fires twice, at the beginning and then again at the end of the exposure.

Is the first flash only for metering and the second flash is the one that appears in the picture or is it like 2 flashes in the same exposure, one at the beginning and one at the end?

Thanks for the help!

:grouphug:
Marlton Mom
PS. this flash arrives tomorrow so I don't have the manual quite yet.

VVFF
06-02-2011, 10:51 PM
The first flash is for flash metering on your subject. The second flash is the true flash that is adjusted for correct exposure of your subject.

disneyboy2003
06-02-2011, 11:09 PM
I have a question about flash settings.

For the Nikon SB 700 in Slow Sync + Rear Curtain mode the flash fires twice, at the beginning and then again at the end of the exposure.

Is the first flash only for metering and the second flash is the one that appears in the picture or is it like 2 flashes in the same exposure, one at the beginning and one at the end?

Thanks for the help!

:grouphug:
Marlton Mom
PS. this flash arrives tomorrow so I don't have the manual quite yet.

Congratulations on your new Nikon external flash! You're gonna have lots & lots of fun with it! :thumbsup2

Before I forget, here's the link to the PDF of the User's Manual your Nikon SB700 flash (it's HUGE): www.nikonusa.com/pdf/manuals/Speedlights/SB-700.pdf

Slow Sync is a generic term, referring to using flash & a slow shutter speed together. When would you use slow sync? When it's really really dark or in a very low-light situation. The flash will illuminate your foreground subject. The slow shutter speed will brighten the dark background.

There are 2 different ways of "slow sync-ing": front-curtain sync and rear-curtain sync.

In front-curtain sync, the flash fires immediately after the shutter opens. Then, the shutter stays open for the duration of the exposure before closing. In this case, the flash fires at the beginning of the exposure.

On the other hand, in rear-curtain sync, the shutter opens for a while, and right before the shutter closes, the flash fires. In this case, the flash fires at the end of the exposure.

Why would you use rear-curtain sync? If you've got a moving subject that will create a streak of light, you'd use rear-curtain sync to make the subject look like it's moving forward. Here's an example from the Internet:

http://www.shortcourses.com/images/b4ch6/curtainsync.jpg

In the top example, the picture of the train was taken using front-curtain sync. The flash fired first, and then the train continued moving forward. In the end, the picture looks like the train is moving backwards! :eek:

In the bottom example, the picture of the train was taken using rear-curtain sync. The shutter opens first, and the train moves forward. It's not until the end of the exposure that the flash fires. In the end, the picture looks like the train is moving forward!

You can also use rear-curtain sync during the 4th of July, when your son uses a sparkler to write his name in the air. With rear-curtain sync, the flash fires at the end, so it looks like he's finished writing the last letter of his name. If you had used front-curtain sync, it would look like he's at the beginning of his name, when the rest of his name is already written in sparkles.


So, to answer your question, why are there 2 flashes in rear-curtain sync? The first flash is for camera metering and does NOT appear in the picture. Afterwards, the shutter opens for a long time, and then the rear-curtain sync flash fires. This rear-curtain sync flash is the one that actually appears in the picture. Your 1st statement was correct.

Hope that helps. Congrats again! :)

Daisy14'sDH
06-02-2011, 11:22 PM
Great info here! I gotta get a good flash someday!

mom2rtk
06-03-2011, 09:34 AM
Flash photography continues to befuddle me....... but one step at a time Disneyboy is getting through to me.........That all made complete sense! :thumbsup2

What's tomorrow's flash lesson?

boBQuincy
06-03-2011, 10:43 AM
A really good explanation of 2nd curtain sync by DisneyBoy!

disneyboy2003
06-03-2011, 10:55 AM
Flash photography continues to befuddle me....... but one step at a time Disneyboy is getting through to me.........That all made complete sense! :thumbsup2

What's tomorrow's flash lesson?

:flower3: Thanks so much for the compliment. For a long long time, I avoided learning about flash because I was intimidated by it and I didn't understand it. Even the topic of "rear-curtain sync" took me a long long time to sit down & read about it. It took me a long time to understand it, too. So I'm pleasantly surprised that you found my ramblings clear. :)

Nowadays, I bring my external flash everywhere with me, even during the day. I don't limit my flash use to just low-light / night time photography. I use it quite often during the day, mostly as fill-flash, and it really makes my subject "pop". The key, however, is to use a subtle amount of flash, so that it doesn't look like you used flash. :3dglasses


A really good explanation of 2nd curtain sync by DisneyBoy!

Thanks so much, boBQuincy. :)

Marlton Mom
06-03-2011, 11:20 AM
Thanks for the great replies everyone!

The thing about this flash that I am most excited about is the 'Auto FP' feature that will allow you to over ride the flash mandated restraints on aperture and shutter speed and really open up the lens for a nice bokeh or a freezing of the action or both. I am planning on giving those fountains in EPCOT a work out so we'll see what this flash amateur can do.

The UPS "Mom" just arrived with the box so I've got some reading to do. The manual comes in english and spanish so if you want to brush up on your old Espanole skills while driving yourself crazy with the technical jargon you got your work cut out for you. Nikon also includes an 'example photo' booklet for us visual learners so that should really help as well.

I posted on another Flash thread how I ordered a Bower flash specifically for my Nikon that was causing problems with the power supply to the camera (D90). I paid about $140 dollars more for the Nikon over the Bower with the macro ring.

I have to say that the information that I've been able to find, teaching me about this Nikon flash surely trumps the lack of helpful info I got with the Bower 2 page "manual".

I think the bottom line is this:
A) Nikons only seem to want to work with Nikon Flashes, based on the comments I've seen on the boards here, plus my experience.
and
B) For a Flash newbies like myself I think the info that you're going to find that is relevant to your Nikon flash in addition to the increased 'ability'/'functionality' of this flash more than makes up for the price difference.

I'm sure that with the proper knowledge, someone could dig through the haystack and find the off brand flash that can work well with the D90. What I'm saying is that for a beginner Nikon is the way yo go!

Thanks for all the info guys/gals. :worship:

If you have any shot ideas that you'd like to share for the Auto FP mode let me know and I'll give it a try. I'm taking all my gear so I plan on having fun at night taking pictures in the parks.

~Marlton Mom

disneyboy2003
06-03-2011, 12:11 PM
I posted on another Flash thread how I ordered a Bower flash specifically for my Nikon that was causing problems with the power supply to the camera (D90). I paid about $140 dollars more for the Nikon over the Bower with the macro ring.

I have to say that the information that I've been able to find, teaching me about this Nikon flash surely trumps the lack of helpful info I got with the Bower 2 page "manual".

I'm sorry to hear about your previous experiences with your old flash.

However, reading about your experiences, it sounds like a perfect example of mom2rtk's recent quote: "The most expensive piece of equipment is the one you have to buy twice."

In this case, you paid twice for an external flash, and in the end, you end up with a Nikon flash anyway. With that same amount of money, you probably could have bought Nikon's high-end flash, the SB900, and probably have some $$$$ to spare.

This same argument can be applied to many types of photography equipment:

Do I buy the cheaper lens or the more expensive lens?
Should I buy the cheap tripod from Walmart or the much more expensive one with carbon fiber?
Do I buy a cheap UV filter or the multicoated super-thin UV filter? (although some might argue it's cheaper not to buy a filter at all :rolleyes:)


In the short term, I know that it's very tempting to try to save some money on off-brand or lesser-known brands' equipment. I figure, though, that in the long term, I'm just going to end up with the more-expensive piece of equipment anyway. I might as well just shell out the $$$$$ up-front right now. In the long term, it's actually cheaper this way.

Marlton Mom, I hope you don't take offense to what I've written above. I, myself, have often been tempted to buy off-brand or off-off-brand photography stuff. But I've really had to remind myself frequently of mom2rtk's wise quote.

I guess I just convinced myself to buy that new Canon 70-200mm f/2.8 IS lens. It's "cheaper" this way, isn't it? :rolleyes1

Marlton Mom
06-03-2011, 12:54 PM
Nope, Marlton Mom didn't pay twice. She had the Bower for all of 1 day, realized it was a dud and she sent it back to B and H for a full refund, minus the $8 dollar shipping back to B and H.

You do bring up a lot of really great points though. :thumbsup2

I think it's key here to also know your suppliers return policy and to check out your equipment as soon as it crosses your doorway.

I'll take the $8 dollar lesson and know that sometimes you get the bear, sometimes the bear gets you!

Marlton Mom


I'm sorry to hear about your previous experiences with your old flash.

However, reading about your experiences, it sounds like a perfect example of mom2rtk's recent quote: "The most expensive piece of equipment is the one you have to buy twice."

In this case, you paid twice for an external flash, and in the end, you end up with a Nikon flash anyway. With that same amount of money, you probably could have bought Nikon's high-end flash, the SB900, and probably have some $$$$ to spare.

This same argument can be applied to many types of photography equipment:

Do I buy the cheaper lens or the more expensive lens?
Should I buy the cheap tripod from Walmart or the much more expensive one with carbon fiber?
Do I buy a cheap UV filter or the multicoated super-thin UV filter? (although some might argue it's cheaper not to buy a filter at all :rolleyes:)


In the short term, I know that it's very tempting to try to save some money on off-brand or lesser-known brands' equipment. I figure, though, that in the long term, I'm just going to end up with the more-expensive piece of equipment anyway. I might as well just shell out the $$$$$ up-front right now. In the long term, it's actually cheaper this way.

Marlton Mom, I hope you don't take offense to what I've written above. I, myself, have often been tempted to buy off-brand or off-off-brand photography stuff. But I've really had to remind myself frequently of mom2rtk's wise quote.

I guess I just convinced myself to buy that new Canon 70-200mm f/2.8 IS lens. It's "cheaper" this way, isn't it? :rolleyes1

disneyboy2003
06-03-2011, 01:34 PM
Nope, Marlton Mom didn't pay twice. She had the Bower for all of 1 day, realized it was a dud and she sent it back to B and H for a full refund, minus the $8 dollar shipping back to B and H.

...

I think it's key here to also know your suppliers return policy and to check out your equipment as soon as it crosses your doorway.

Whew! I'm so glad to hear that your entire ordeal didn't cost you an arm & a leg.

In your case, you figured out right away that the cheaper equipment didn't work out for you. Other people, on the other hand, may not realize how bad their cheaper equipment is until well past the return policy date. That's when "cheaper" stuff actually becomes more expensive. :sad1:

mom2rtk
06-03-2011, 02:26 PM
I guess I just convinced myself to buy that new Canon 70-200mm f/2.8 IS lens. It's "cheaper" this way, isn't it? :rolleyes1

LOL! That reasoning hasn't even worked on ME yet! (well, not for that lens yet anyway....) :rotfl:

I say go for it!

Here's another word of wisdom from mom2rtk: It's always easier to spend someone ELSE'S money!

MM: I'm sure you'll do great things with your new flash. Learn it all here and translate in to Canon-ese for me, will you? Maybe between you and Disneyboy, I'll have that flash lightbulb moment yet! :idea:

boBQuincy
06-03-2011, 03:19 PM
subtle[/I] amount of flash, so that it doesn't look like you used flash. :3dglasses


Subtle is right. I have found that on my Canon Xsi the built-in flash
needs to be turned down by about 1 stop to look good as a fill flash.

handicap18
06-03-2011, 05:39 PM
However, reading about your experiences, it sounds like a perfect example of mom2rtk's recent quote: "The most expensive piece of equipment is the one you have to buy twice."

This same argument can be applied to many types of photography equipment:

Do I buy the cheaper lens or the more expensive lens?
Should I buy the cheap tripod from Walmart or the much more expensive one with carbon fiber?
Do I buy a cheap UV filter or the multicoated super-thin UV filter? (although some might argue it's cheaper not to buy a filter at all :rolleyes:)


In the short term, I know that it's very tempting to try to save some money on off-brand or lesser-known brands' equipment. I figure, though, that in the long term, I'm just going to end up with the more-expensive piece of equipment anyway. I might as well just shell out the $$$$$ up-front right now. In the long term, it's actually cheaper this way.

I guess I just convinced myself to buy that new Canon 70-200mm f/2.8 IS lens. It's "cheaper" this way, isn't it? :rolleyes1

I did this with the Sigma 24-70mm f/2.8. I got it for a little over $500. After about 6 months of using it I realized it wasn't for me and I was very disappointed in its low light performance, especially with finding focus and then getting focus correct. I tried to use it at a wedding I was getting paid to shoot and I was not getting good results. Luckily I had my Tamron 17-50mm f/2.8 and that worked great. But I really wanted that 24-70mm f/2.8 focal length.

This past Christmas I asked for amazon gift cards and also got some cash. I saved for a few more months and then when we got our yearly bonus in March I bought the Nikon 24-70mm f/2.8. WOW what a difference. Haven't had one issue and other than for a few baseball games when i needed the 70-300mm lens, the 24-70 hasn't left my D300.

I still have the Sigma and the box and everything. I just need to get around to selling it on e-bay and hopefully get $300-400 for it.