Clockunder
New Member
ah i see. thanks for the explanation.
Don't listen to wind30 or anyone. As I've said clearly in my previous post, most websites prefer to state the guideline using the equivalent focal length but at the end of the day, it's what you experience practically for your own handhold shooting that matters.
Try it yourself and see what kind of shutter speed you're able to handhold for the vavious focal lengths.
Sharing my personal view and observation :
Through observation and my own practical experience, if the equivalent focal length is used as guide, it can't explain many of the shutter speeds many people are capable of shooting at handheld at various focal lengths, especially for those cameras with huge crop factors (e.g. prosumers cameras typical crop factor is 4-6 times and compact digicams are mostly 6 times) during those days where there was no image stabiliser (e.g. 1/8 or 1/15 easily handheld on compact digicams without IS at 35mm equivalent). In addition, if equivalent focal length is used as guideline, then it tends to imply that most image stabilisers work for 3 to much as nearly 5 [e.g. Olympus SP550UZ 1/10-1/20 at 507mm equivalent and image stabilised compact digicams at < 1/10 shutter speeds at 105mm equivalent (4 stops stabilisation? Check out the websites such as DPreview for reviews for compact digicams and you will find lots of image stabilser tests at 1/10 or slower for 105mm equivalent (actual focal length = 15-20mm)] and oddly, the smaller the sensor, the more stops the image stabiliser appears to work. However, if you use actual focal length to explain them, then everything seems to fall nicely into place for what is happening practically and the consistent conclusion is that most stabilisers work for 2-3 stops. (To test effectiveness of image stabiliser, find out threshold shutter speed by shooting with image stabiliser OFF at decreasing shutter speeds until handshake blur is recorded and then turn the image stabiliser ON to shoot and see how much improvement there is.)
Here's a picture which I took handheld without any image stabiliser a few months ago (had to follow the models and also no space for support of any kind in those crowd):
Actual Focal length : 71.2mm
35mm format equivalent focal length : 280mm
Shutter speed : 1/60
Flash : not fired.
ISO : 400
(EXIF info are intact in the picture)
I shoot in many occassions at the above settings for indoor events because that's about the limit I can accept for low light condition. At 1/60, I do sometimes experience handshake blur because it's a tad slower than 1/71.2 guideline based on actual focal length and in this picture, there is slight motion blur at the model's hands due to the model's movement as the shutter speed is too slow to freeze all movement. When I used 1/125, I almost never get any handshake blur at 71.2mm actual focal length (280mm equivalent on 35mm format).
My explanation for the above is : For different sensor sizes, the focal length and the image (except the "crop") are the same except the sensor size and so, the only difference is the magnification to the same viewing size. How much the physical image projection shift on the sensor is not affected by your shooting distance (which is why there is no shooting distance variable in the guideline) and the sensor sizes (which are just backwall sizes for the image to fall on).
If the shutter speed is fast enough then the physical image will not shift too much on the sensor to be recorded. If there is handshake blur recorded, then it will of course be more visible with higher magnification factor. However, it there is no handshake blur recorded, then there is no blur to be magnified even if it's 2x or even 4x or 6x magnification.
In my case, the magnification factor is 4x. If I have to follow the equivalent focal length guideline, I would have to shoot at 1/280 (more than 2 stops faster than 1/60) or faster at 71.2mm (280mm equivalent).
Don't just blindly accept what others or websites say. So try it out and observe yourself and use your own guide.
Something for you to think about :
1 photographer using Canon 5D (full frame) and his friend using Olympus E-510 (1/2 frame) shooting at a fashion show from about the same spot (e.g same 10m distance away from the model because there isn't space elsewhere due to the huge crowd) using the same fixed focal length 100mm (prime lens which is 200mm equivalent for the E-510) at the same 1/100 shutter speed at same aperture (F/4) with the same amount of physical handshake and the E-510 has image stabilisation turned OFF.
So the physical image on the sensor will shift the same amount for the same amount of handshake because a difference in sensor size (being just the screen size) does not affect the shake in the physical image and the 5D has a larger field of view than the smaller sensor E-510. The recorded image will be exactly the same except for the composition where the 5D has recorded additional areas outside the perimeters of the E-510 sensor. After shooting, the 5D photographer goes back home, loads his picture onto the photo-editing software on his PC and crops his picture to be exactly the same composition as the E-510. His cropped picture would be exactly the same one shot using E-510 at the same 10m away using 100mm at 1/100 shutter speed @F/4.
So the question is : If there is no handshake blur for the original 5D picture taken 10m away with 100mm @1/100, do you expect to see handshake blur in the cropped picture for the 5D? Logically, your answer should be the same as for the one taken with the E-510 same distance 10m away with 100mm at 1/100 with image stabiliser turned OFF. The cropped 5D picture and the E-510 picture are taken technically the same (focal length 100mm, aperture F/4, distance 10m with the same amount of physical handshake), have the same composition and will have the same magnification factor for any viewing size now. Think about it.
Last but not least, think about the slow shutter speeds (below 1/15) handphone cameras are capable of taking handheld without handshake blur even though there is no image stabiliser on them, equivalent is 35mm and above and it's easy to have hand shakes with such a small device.
Again, in the real world, don't just blindly quote websites and accept what is stated in the websites as gospel truth. Go out and try to discover what is real in practice to you. If I had blindly taken what websites and other people tell me, I would have tried to keep my shutter speed faster than 1/280 at 71.2mm (280mm equivalent) and this means pumping up my ISO by 2 stops (since max. aperture already and anyway, unable to, because max. is ISO 800) and introduce much more noise into my pictures unnecessarily.
I say it again : If you have average steady hands like mine, use 1/actual focal length. If you have shaky hands, use 1/equivalent focal length. If you have very shaky hands, then use 1/equivalent focal length + 1 stop faster shutter speed.
More examples of my handheld shots (most of them handheld by ensuring shutter speed was faster than 1/actual focal length but happen to be much slower than 1/equivalent focal length. Some shots were made with camera held overhead using the LCD screen as viewfinder. I only used tripod if the shutter speed is clearly slower than 1/actual focal length because my numerous past experiences taught me that there would be handshake blur if handheld in those cases. EXIF are all intact in the pictures):
http://forums.clubsnap.org/showthread.php?t=259853
http://forums.clubsnap.org/showthread.php?t=247984
myself too. I bought my E 410 last week at HN Funan and you can only get the "freebie-less" price when you ask at the shop as they cannot advertise the lower than RSP (probably that's why they can hold more stock as well). Similar with the earlier post-er - I also opt for the full package with the dry box (which I Was already going need anyway). So not too bad lah. 
