Focusing Problems

[newsalt]

I have a Canon PowerShot S3IS and I'm having trouble getting it to focus when I try to take close-ups shots of my corals. I'm not looking for Macro shots, just something close-up. It seems like the camera is focusing on the tank glass or something. Even if I use the Macro or Super Macro feature, it's always blurry. If anyone is using this camera, can you please offer some suggestions. Do I have something set incorrectly? Please help.

Thanks.

 

[nickb]

Can you set the camera on manual focus (my Canon p&s has that option)? That is usually preferred when taking photos inside a glass tank since the autofocus gets confused.

There are a lot of possible reasons for blurry photos. If you can give more details (e.g. shutter speed, aperture size, are you using a tripod, do you turn off the pumps), and perhaps post an example, that might help.

 

[newsalt]

I've never tried the manual focus. I've tried to get shots at all different shutter speeds and aperatures. I don't use a tripod, or turn off the pumps.

Here's a shot I tried of a frogspawn in my frag tank. Horrible.

 

[nickb]

See what you mean

From the EXIF info, that picture was taken using a shutter speed of 1/100 sec and an aperture of f3.2. At that speed, a tripod wouldn't be essential but with the f3.2 aperture, the depth of field will be quite narrow, making focusing very critical. Have a look at the material starting on page 64 of the advanced users manual for your camera - it explains about using manual focus and focus lock. That should help. Using a tripod will help for most tank photos. Plus, when using the tripod, try taking the picture using the self-timer - when you press the shutter, there is a chance that you will cause some camera vibration which will make the image unclear. Finally, what ISO setting were you using - the picture seems to have a lot of noise which suggest that the ISO was very high. You will get better results at a lower ISO which which will lower your shutter speed and make a tripod even more important.

 

[newsalt]

Thanks for the advice. If I don't use a high ISO speed, then the camera what to use the flash. I'm trying to avoid the flash because it don't make the picture look right.

 

[nickb]

I agree - flash generally doesn't work well with photos through glass (with off-camera flash, you might have more options). I have a Canon PowerShot A590 which has a control on the back to disable the built-in flash (I use it regularly since the camera takes up to 5 seconds to re-cycle after taking a flash photo during which time I can't even take a non-flash photo ). I don't see a similar switch on the S3IS but, if you don't manually open the flash, wouldn't that disable the flash completely?

Also, which mode are you shooting in? Most macro shots will use 'M' (or perhaps Av) mode. This should disable automatic ISO and flash selection and give you more control.