How much wood would a wood duck duck....

[gotrocks]

Wish I had Cara's or Kristine's long lens/camera for this morning.

[SARtech]

You don't have a telephoto? You must have been really close! My zoom only goes to 300mm and that is surely not long enough for me now.
Love the reflections.

[gotrocks]

Kristine,
My sony says 15X optical zoom, these were max zoom.

I wonder if 15x means 15x more that where the lens starts.:confused5:

I really don't fully understand "zoom" terms.
My lens is 2.7-4.5/5.2-78.
What does this mean?
How would it compare to a 50-300 for example?

[Singletracklovr]

Sony Cyber-shot DSC-H50's 15x equals f2.7-f8 31-465mm-equivalent lens.
hth

[OldClicker]

Kristine,
My sony says 15X optical zoom, these were max zoom.

I wonder if 15x means 15x more that where the lens starts.:confused5:

I really don't fully understand "zoom" terms.
My lens is 2.7-4.5/5.2-78.
What does this mean?
How would it compare to a 50-300 for example?

Yes, 15x means that the longest focal length (78mm) is 15 times the shortest (5.2mm).

Because the sensor is only about 1/4th the size of the most common DSLR, you only see about 1/4 the view in the frame. This means that you are likely to move back about 4 times as far to get the same image. [EDITED - So, since you are 4 times are far for the same image, it seems like the lens is 4 times as long or 21-310mm.] – TF

[gotrocks]

Thanks Oldclicker and Bob for the explanation.

"Yes, 15x means that the longest focal length (78mm) is 15 times the shortest (5.2mm)."

I get the 15 x 5.2 but still am confused by

"the lens is 4 times as long or 21-310mm"
and
"Sony Cyber-shot DSC-H50's 15x equals f2.7-f8 31-465mm-equivalent lens."

[Loupey]

Because the sensor is only about 1/4th the size of the most common DSLR, you only see about 1/4 the view in the frame. This means that you are likely to move back about 4 times as far to get the same image. [EDITED - So, since you are 4 times are far for the same image, it seems like the lens is 4 times as long or 21-310mm.] – TF

Yeah, this is very confusing to me too.

Remember that the keystone to "crop factor" is that the camera-to-subject distance does not change. If it does, the "equivalency" comparison falls apart.

gotrocks, the "31-465mm equivalent" means that you get the full image - same angle of view- that someone standing in your exact spot would get with a 31-465mm zoom lens attached to a 35mm film (or full-frame digital camera).

Think of a large LCD television monitor as the image produced by a given lens. Hold an 8 1/2" x 11" paper up to it and think of what that paper encompasses as the field of view captured by a 35mm film (or whatever). Now hold a Post-It note up to the same monitor and it appears that the Post-It is capturing a zoomed image. In otherwords, it takes less lens (or monitor) to produce an equivalent field of view with a smaller sensor. In this example, it would take a smaller LCD so that the Post-It would capture the same angle of view as did the 8 1/2" x 11" sheet did with a larger monitor. Aspect ratio notwithstanding, but you get my drift I hope.

[OldClicker]

Thanks Oldclicker and Bob for the explanation.

"Yes, 15x means that the longest focal length (78mm) is 15 times the shortest (5.2mm)."

I get the 15 x 5.2 but still am confused by

"the lens is 4 times as long or 21-310mm"
and
"Sony Cyber-shot DSC-H50's 15x equals f2.7-f8 31-465mm-equivalent lens."

"31-465mm-equivalent lens." He is comparing it to a 35 mm film camera (or full frame DSLR) with no explaination why. Does this mean anything to you? I don't think it means anything to anyone who ever asks the question.

My explaination was how and WHY it compares to the much more common size DSLR sensor. Doesn't it make sense? If you are taking a picture of a person's face, And you only get the eyes and nose, wouldn't you move back. Taking the same image after moving back 4 times as far makes it seem like the lens is 4 times as long.

TF

[OldClicker]

Yeah, this is very confusing to me too.

Remember that the keystone to "crop factor" is that the camera-to-subject distance does not change. If it does, the "equivalency" comparison falls apart.

gotrocks, the "31-465mm equivalent" means that you get the full image - same angle of view- that someone standing in your exact spot would get with a 31-465mm zoom lens attached to a 35mm film (or full-frame digital camera).

Think of a large LCD television monitor as the image produced by a given lens. Hold an 8 1/2" x 11" paper up to it and think of what that paper encompasses as the field of view captured by a 35mm film (or whatever). Now hold a Post-It note up to the same monitor and it appears that the Post-It is capturing a zoomed image. In otherwords, it takes less lens (or monitor) to produce an equivalent field of view with a smaller sensor. In this example, it would take a smaller LCD so that the Post-It would capture the same angle of view as did the 8 1/2" x 11" sheet did with a larger monitor. Aspect ratio notwithstanding, but you get my drift I hope.

I think the "35mm equivalent" means nothing except to those who already know the answer. A smaller sensor gives a smaller image therefore you move back. If the sensor is ¼ size, you move back 4 times the distance and the lens seems like it is 4 times as long. – TF

[gotrocks]

Thanks again, now let me "chew" on this info for a while and see if I can digest at least part of the "formula".

I'm assuming that my Sony("31-465mm equivalent") is getting as MORE "zoom" and a wider angle than a 50-300 lens.

If that is correct then my question has been answered.

[SARtech]

LOL..... none of this makes sense to me. Maybe I need another cup-o-joe.
It all seems like comparing apples to oranges to me.

[Loupey]

"31-465mm-equivalent lens." He is comparing it to a 35 mm film camera (or full frame DSLR) with no explaination why. Does this mean anything to you? I don't think it means anything to anyone who ever asks the question.

You and I have gone around this tree more than once

The comparison to 35mm film is normal because that is still the one "standard" by which the other formats can be based. Like it or not, most people are going to want to compare one system and format to another and using the long standing standard of the 35mm film format is still the best way to do that.

Instead of the 31-465mm equivalent, I could have easily compared the said camera/lens to:

50~744mm in Canon's APS-C format, or
40~605mm in Canon's APS-H format, or
47~698mm in Nikon's DX format, or
62~930mm in Olympus format

Nah, it's just easier to compare to the 35mm film format since the others are based against the same standard.


EDIT: Computations incorrect - see post #16

[Loupey]

I'm assuming that my Sony("31-465mm equivalent") is getting as MORE "zoom" and a wider angle than a 50-300 lens.

Again, it depends on the format that the 50-300mm lens is working with. Look how the imaging sensor crops the images differently on different formats to achieve the corresponding focal length equivalents (again using the 35mm film format for comparison):

Canon 1.6x bodies: 80-480mm
Canon 1.3x bodies: 65-390mm
Canon/Nikon/Sony 1.0x bodies: 50-300mm
Nikon DX bodies: 75-450mm
Olympus bodies: 100-600mm

[OldClicker]

Thanks again, now let me "chew" on this info for a while and see if I can digest at least part of the "formula".

I'm assuming that my Sony("31-465mm equivalent") is getting as MORE "zoom" and a wider angle than a 50-300 lens.

If that is correct then my question has been answered.

As long as you keep the "zoom" in quotes (apparent zoom), yes you are correct when comparing the 31-465mm on a 35mm film/sensor camera. - TF

[OldClicker]

QUOTE=Loupey

You and I have gone around this tree more than once

And will continue to do so.

The comparison to 35mm film is normal because that is still the one "standard" by which the other formats can be based. Like it or not, most people are going to want to compare one system and format to another and using the long standing standard of the 35mm film format is still the best way to do that.

For those who typically ask the question, when you say simply 'xxx-xxx equivalent' you might as well be comparing it to the moon.

Instead of the 31-465mm equivalent, I could have easily compared the said camera/lens to:

50~744mm in Canon's APS-C format, or
40~605mm in Canon's APS-H format, or
47~698mm in Nikon's DX format, or
62~930mm in Olympus format

Perfect example of the confusion caused, since one of is definitely confused. I'm pretty sure you went the wrong direction. The APS-C would seem like a 21-310mm to the OP.

Nah, it's just easier to compare to the 35mm film format since the others are based against the same standard.

When I first started (a brief 1 1/2 years ago), this was the most confusing concept until I figured out that it was just wrong. The lens doesn't change a thing just because you change the sensor size. The 'equivalent' shorthand explanation may work for the experienced, but to the new shooter, it's a disaster.

[Loupey]

Perfect example of the confusion caused, since one of is definitely confused. I'm pretty sure you went the wrong direction. The APS-C would seem like a 21-310mm to the OP.

You are correct, my mistake.

The Sony DSC-H50's lens/sensor combo would be compatible to:
Canon's APS-C: 20-291mm
Canon's APS-H: 24-358mm
Nikon's DX: 21-310mm
Olympus: 16-233mm

[gotrocks]

Thanks again Gents,
I appreciate all the time spent in explaining this complicated question.

I'll keep on shooting with what I have and try to improve the subject matter and proper settings.

I don't guess we have answered the original question,
"How much wood....":blush2:

[JordanRHughes]

Cool! I've never seen one with a paint job like that. Thanks for the share.

Jordan.