POLL: 1/focal length rule

Which one is correct?


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UY79 said:
I'm going into whether anyone follow this rule or not debate. It's impossible.

But saying crop factor just crops the view of the image and yet having the same quality as the original is something else.

Cheers!

just be comfortable with your own acceptable hand holding speed, dun get too hung up about rules.

despite so many ppl telling me, i still think crop factor is not enlargelment as what ah pao say. I'm not so into the science of things and i still get my bloody sharp images while not following this mutipuler 'rule'.
 

So difficult to use 1/focal length x crop factor! Must carry calculator when go shooting? ;p

I use 1/focal length as a general guide and always got sharp pics.
 

Virgo said:
So difficult to use 1/focal length x crop factor! Must carry calculator when go shooting? ;p

I use 1/focal length as a general guide and always got sharp pics.

I use Auto setting and I get sharp pictures too.... even at 380mm ;p
 

UY79 said:
If you print both the original and the cropped image at say 8R, which of these has more enlargement done to it?

Cheers!

Following this logic, it does seem plausible that we should follow the (1/focal length x crop factor) rule.

Flaws get magnified as the final image gets enlarged. So, to play safe the (1/focal length x crop factor) rule should work.

Whatever the case, I'm personally not too bothered which one is the correct one. I use the easier-to-remember (1/focal length) rule to GUIDE my work (SLRs only). In the end, it boils down to correct handholding techniques and working within the boundaries of my equipment.

Good discussion though. Will keep that in mind when I need to convince my technical friends. :)
 

Ah Pao said:
Whatever the case, I'm personally not too bothered which one is the correct one. I use the easier-to-remember (1/focal length) rule to GUIDE my work (SLRs only). In the end, it boils down to correct handholding techniques and working within the boundaries of my equipment.

Good discussion though. Will keep that in mind when I need to convince my technical friends. :)

Agreed. Different lenses, because of their size and weight, provide different stability when holding them. It's getting to know what one can do with the equipment he or she has that's is the more important.

Cheers!
 

next time if u guys get a p&s digicam, be sure to stick to your beliefs and shoot at 1/focal length. u wun need any shutter speeds above 1/60 to avoid handshakes.

~MooEy~
 

UY79 said:
I'm going into whether anyone follow this rule or not debate. It's impossible.

But saying crop factor just crops the view of the image and yet having the same quality as the original is something else.

Cheers!

I think what some of the guys are saying is that if the original is already sharp, the crop of the original will be just as sharp. Magnification exaggerates flaws that already exist in the originals. If there weren't any flaws in the first place the magnification "required" from the crop factor doesn't affect it.

In such a large world as ours, there will invariably be people who are very steady and be able to take shots at less than ideal conditions and there'll be others that can't hold a camera as steady (much like why some people are snipers and the rest are bo bo shooters in range ;) )

As for the arguments about using PnS with 1/60... well maybe if the PnS were built with better handgrips and weight it'll be possible. Else, I think that's a harder ask to follow when you're holding most of those cameras by a few fingers.
 

RiStaR said:
I think what some of the guys are saying is that if the original is already sharp, the crop of the original will be just as sharp. Magnification reveals flaws that already exist in the originals. If there weren't any flaws in the first place the magnification "required" from the crop factor doesn't affect it.
Everything is relative, you are not going to get a magical perfectly sharp shot at any time. It just a matter of blurred, less blurred, hardly blurred.

Basically, some of the arguments are already going off the mark. The original question is whether you would add additional shutter speed on top of the 1/focal length rule to account for the crop factor.
As for the arguments about using PnS with 1/60... well maybe if the PnS were built with better handgrips and weight it'll be possible. Else, I think that's a harder ask to follow when you're holding most of those cameras by a few fingers.
There are many digicams with vertical grips which offer a pretty firm hold on the camera, like the CP5700 series, Dimage 7 series.
 

MooEy said:
next time if u guys get a p&s digicam, be sure to stick to your beliefs and shoot at 1/focal length. u wun need any shutter speeds above 1/60 to avoid handshakes.

~MooEy~

no need, dun like a digital p&s anyway unless until its full frame and can go iso800 relatively clean.
 

Zerstorer said:
Everything is relative, you are not going to get a magical perfectly sharp shot at any time. It just a matter of blurred, less blurred, hardly blurred.

Thing is, I don't see many people printing larger than A4, even then, the magnification "required" ain't that much versus a FF camera.

Basically, some of the arguments are already going off the mark. The original question is whether you would add additional shutter speed on top of the 1/focal length rule to account for the crop factor.

Ok :)

There are many digicams with vertical grips which offer a pretty firm hold on the camera, like the CP5700 series, Dimage 7 series.

The bodies are still a teeny bit small to be comfortable... the closest i'd think is the Dimage A series...pity bout EVFs... just can't really get used to it :(
 

RiStaR said:
Thing is, I don't see many people printing larger than A4, even then, the magnification "required" ain't that much versus a FF camera.
(

Whether people do it or not is another matter, the crux of the issue now is that the question is whether additional shutter speed is required to get the same apparent results.

Remember that photography guidelines such as DOF and reciprocal focal length rules are recommendations for a acceptably sharp shot for a certain level of enlargement(typically 8R). If you are printing larger one would generally recommend a tripod or stepping down even more.

Similarly, when the CCD is smaller than standard 35mm, it is being enlarged to a greater degree.

One's personal prowess at holding at xx speed doesn't come into discussion here as its all a relative measure.
 

Zerstorer said:
Whether people do it or not is another matter, the crux of the issue now is that the question is whether additional shutter speed is required to get the same apparent results.

Remember that photography guidelines such as DOF and reciprocal focal length rules are recommendations for a acceptably sharp shot for a certain level of enlargement(typically 8R). If you are printing larger one would generally recommend a tripod or stepping down even more.

Similarly, when the CCD is smaller than standard 35mm, it is being enlarged to a greater degree.

One's personal prowess at holding at xx speed doesn't come into discussion here as its all a relative measure.

Ok... if that's the case can I just say that everyone here is agreeing that the focal length doesn't change and that the 1/Focal length rule is just a guideline. With that being said, all that matters now is how big do you want your prints. EDIT1: I mean if you were going to print larger than 8R on film you'd have to increase the shutter speed, too. So I think it's the prints not the crop factor that matters.

If everyone is just printing 4Rs I'm sure you'd be able to get away with 1/<focal length and 8Rs 1/Focal length (+- depending on what and what not) and larger you'd want 1/Focal length + a few stops. I know that if I ever came across a moment that I'd know I want enlarged I wouldn't take any chances.

Lastly, I've seen photos that have a reasonable amount of shake (especially street shooting) but that didn't stop me from admiring it. Is critical sharpness such a big issue that a guideline has to be made a rule? It'll be a sad day if a new guy comes in and reads her if i want sharp pics i should take them with 1/320 (200mm with a 300d) and come back finding it ain't sharp. "But I did what they said to do?!"

I'd be inclined to just advise everyone to determine their own capabilities--or limits.
 

i dont think we are discussing the different handholding capabilities of various people. I think the guideline when used with dSLRs should include the crop factor. I admit however, that I often forget that in the field but still manage to come up with pretty sharp pics. With my film shots however, I've can consistently produce sharp pics 1 stop slower than the guideline.
 

Virgo said:
So difficult to use 1/focal length x crop factor! Must carry calculator when go shooting? ;p

I use 1/focal length as a general guide and always got sharp pics.

lucky the crop is 1.5 or 1.6, if the crop is 1.3232493, then we have more problem doing the calculation liao. ha ha
 

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This is the correct formula for stabilized image.
 

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I believe that with good hand holding techniques and modern stabilisation technology, this guideline is becoming less and less relevant for me personally. I've come up with my own set of guidelines based on experience:

10-20mm lens- 1/2s or faster
16-80mm lens, about 1/10 to 1/20s or faster (1/8s at the 16mm end)
70-200mm, 1/30s or faster.
 

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