Focal lenght on a Compact Camera

[jonbeeza]

I am trying to figure out matching the shutter speed against the focal length on my Compact Camera, the Camera is the Panasonic TZ35. It displays the focal length on the LCD display as, X1 X2 X3 all the way up to X20 at the maximum 20X zoom. I have taken twenty photos from the widest X1 zoom all the way to the 20X zoom, and I have looked in all of the files. I have put the info from a couple here.

The widest is 1X zoom display file info shows Focal length 4mm and then 35mm focal length 24mm

Longest 20X shows 86mm focal length and then 35mm focal length 480mm



So basically as an example, at 20X zoom I am assuming I would need a shutter speed of 480 and not 86. Is this correct ?

 

[jonbeeza]

Trouble is trying to work it out, as the shutter length is shown as 1X zoom 2X zoom all the way up to 20X zoom, and not displayed as 24mm 35mm etc !

 

[Mr Will]

To work out the values you need to know the 35mm equivalent for the wide end first, which in your case is 24mm. This is 1x. 2x is then double that, so 48mm, 3x is 72mm and so on all the way up to 20x = 480mm.

It's not that useful for working out the 1/focal length guideline though. Firstly, You have a good IS system which will bring the required speed down a lot but secondly you will not be bracing the camera against your face, which works against you and raises the required speed. There really is no substitute for getting out and taking some test shots!

 

[jonbeeza]

To work out the values you need to know the 35mm equivalent for the wide end first, which in your case is 24mm. This is 1x. 2x is then double that, so 48mm, 3x is 72mm and so on all the way up to 20x = 480mm.

It's not that useful for working out the 1/focal length guideline though. Firstly, You have a good IS system which will bring the required speed down a lot but secondly you will not be bracing the camera against your face, which works against you and raises the required speed. There really is no substitute for getting out and taking some test shots!

Thanks for that, so I assume working on the following example 1X Zoom is 4mm in Compact terms, but is 24mm in 35mm Terms. So I would base the shutter speed on the 35 mm equivalent ?

Sorry if this is doing anyone's head in who may read it, it is starting to do my head in !

 

[Mr Will]

1x is whatever the lens is at it's widest, yes (and that varies between cameras).

If you are going to base the shutter speed off anything then yes, the 35mm equivalent is the one to go for. The estimate will be a long way off though, so use with caution.

 

[jonbeeza]

1x is whatever the lens is at it's widest, yes (and that varies between cameras).

If you are going to base the shutter speed off anything then yes, the 35mm equivalent is the one to go for. The estimate will be a long way off though, so use with caution.

Brilliant, thanks for the info

 

[Nod]

Thanks for that, so I assume working on the following example 1X Zoom is 4mm in Compact terms, but is 24mm in 35mm Terms. So I would base the shutter speed on the 35 mm equivalent ?

Sorry if this is doing anyone's head in who may read it, it is starting to do my head in !

In one word, yes! The 1/focal length rule of thumb applies to the 35mm equivalent focal length. Personally, I have come to trust my cameras in the semi auto modes to choose a suitable shutter speed for the zoom. A little trial and probably some error should help you find the right limits of your ability throughout the zoom range.

 

[jonbeeza]

In one word, yes! The 1/focal length rule of thumb applies to the 35mm equivalent focal length. Personally, I have come to trust my cameras in the semi auto modes to choose a suitable shutter speed for the zoom. A little trial and probably some error should help you find the right limits of your ability throughout the zoom range.

In aperture priority on a sunny day like today, at ISO 400 at Max 20X zoom that equates to 480mm in 35mm terms, I am getting a shutter speed of 1/100 surely that's not fast enough for the focal length! I did manage to match the shutter speed to the focal length, but the ISO was way up there. Looks like further testing is in order.

Although on Max 20X zoom with 1/100 the image was not too bad , just could have been a little sharper that's all. I did try to keep my arms braced against my hips, will just have to take the tripod along with me next time.

 

[Nod]

John, that's just over 2 stops that the stabilization is giving you which should be well within its capabilities. I've managed a few exposures of between 1/2 and 1 second at full stretch with an XF-1 (as in at its maximum length - 100mm EFL) by tucking in as much as possible and using my wife's advice with breathing technique. They did take a few attempts before I got useable shots but they were worth the extra few seconds the shots took!

There are several small support devices available that are basically small bean bags that screw into the tripod thread and can be pressed against any firm surface to get sharper shots at slower speeds - far easier to carry around than a tripod!

BTW, if it helps, your sensor appears to have a crop factor of about 6x - might help you get your head around the calculations!

 

[jonbeeza]

John, that's just over 2 stops that the stabilization is giving you which should be well within its capabilities. I've managed a few exposures of between 1/2 and 1 second at full stretch with an XF-1 (as in at its maximum length - 100mm EFL) by tucking in as much as possible and using my wife's advice with breathing technique. They did take a few attempts before I got useable shots but they were worth the extra few seconds the shots took!

There are several small support devices available that are basically small bean bags that screw into the tripod thread and can be pressed against any firm surface to get sharper shots at slower speeds - far easier to carry around than a tripod!

BTW, if it helps, your sensor appears to have a crop factor of about 6x - might help you get your head around the calculations!

Thanks for that info Nod yes it is helpful.

Interesting little camera the TZ35, and while it does not have RAW it does get me images that I would not have gotten with my other camera's that have better sensors and RAW facility. I even managed to get a good quality video clip of a squirrel eating, by simply standing still and zooming in.