Want To Try Some Long Exposure Shots

faceman

I have a good on me to try take some long exposure shots, as I havent really done it before so looking for a few pointers.

I have a Sony A350 camera with a 24 - 100mm zoom lens, f3.5 and a 50mm f1.8 prime lens. I also have a set of macro lenses. Obviously i have a tripod too.

Looking for some tips and advice on doing it? I will post up some of the results over the weekend!

Thanks

jpb1974

Dim Light - Dawn/Dusk/Overcast Day
Low ISO - e.g. 50/100
Small Aperture - e.g. F16
ND Filter - reduces light

magicbastarder

do digital sensors suffer from reciprocity failure?

DaireQuinlan

magicbastarder wrote: »

do digital sensors suffer from reciprocity failure?

Nope. It's one of their few advantages over film :-)

xshayx

Have a look at these for ideas
http://www.flickr.com/search/?q=long+exposure&ss=2&s=int
alot of them will have EXIF data - (Actions > View Exif Info)

Gregor Samsa

Sony DSLRs have a default setting of doing dark frame subtraction to reduce noise on long exposures. Other makes might too, but all I know about is Sony.

Basically, for long exposures (and I can't remember what the threshold for this is, but it's definitely less than 15 seconds), the camera will expose for the amount of time, then straight after, it will do a second exposure (but with the shutter closed) for the same amount of time. Then it processes your exposure with the dark one to eliminate sensor noise that comes from the sensor heating up for being in use for so long. During the dark frame exposure, your camera will display "processing" on the screen, and it won't be available for use. It catches people out the first time they do long exposures, and they often think it's a memory card or buffer problem. Sony should have made the messaging clearer. The camera isn't processing, it's shooting. The processing happens in a split second at the end of the dark frame exposure.

It's a feature, not a bug, and it can be turned off (Settings > Long exp.NR > Off). I always keep it off. If I want a dark frame, I'll take it myself. You don't always need one.

So if this is on, and you do a 30 second exposure, the camera will do a further 30 second one straight after. So you won't be able to take another shot until it's finished.

If it's off, you can decide yourself to do your noise reduction in post processing (if needed). You could even manually take a dark frame yourself, and use it in post processing to see if it makes a difference.

The A350 doesn't have mirror lockup, but I've never really had issues with mirror slap on the A350 I used to have, or the A550 I currently have, so don't worry about that.

Using a remote release or the 2 or 10 second timer will help reduce vibrations, even on the tripod.

Also, try turning off Super Steady Shot. Some people report improved results turning it off for tripod work, some don't. I've been turning it off for macro stuff lately. Just put a post-it on your forehead so you don't forget to turn it on again for normal shooting.

magicbastarder

DaireQuinlan wrote: »

Nope. It's one of their few advantages over film :-)

you could call it a disadvantage - if you *want* a long exposure, it gives you a longer one than would otherwise be the case...

faceman

A bit late posting back with an update and I have no photos to show.

Tbh, im having mixed results. I order an ND filter last week online but it hasnt arrived yet. Finding the camera struggling to auto focus in dark conditions. Daylight photos have been hit/miss in getting the brightness levels right.

Going to try some more shots over weekend (hopefully my filter arrives by then.)

landsleaving

Could you set your flash to auto-focus illuminate? that would help for things close to you anyway.

Failing that, with a small aperture you should get good depth of field so you could stand a few feet from the camera - holding a torch if it's really dark, let it focus on you with a timed shot, then set it to manual focus and take your long exposure with it hopefully correctly focused.