weapon of choice

[Killdeer]

Obsolescence.

That's what gets us if senility doesn't.


So, Wease, is the file size smaller too? Does this mean that the "crop-factored" 400mm pic will have less detail than a full-framed 600mm pic?

Did that make any sense?
Killdeer

[jcsnapshot]

Originally posted by Killdeer:
Obsolescence.

That's what gets us if senility doesn't.


So, Wease, is the file size smaller too? Does this mean that the "crop-factored" 400mm pic will have less detail than a full-framed 600mm pic?

Did that make any sense?


Killdeer

Not a smaller file size at all. The crop factor really is only in reference to lenses used. The more or less detail is completely dependent on the quality of glass. A full resolution, fine image is the same no matter what lens is attached.

[Hutch]

So how does crop factor effect the view through the view finder, or does it?


Hutch

[jcsnapshot]

Hutch, It doesn't affect it at all. On my D100, the view finder shows 96% of what will be on the frame. All cameras are different, so check the manual. Even most 35 mm SLRs don't have full frame view finders

[Steve Kendrot]

Jerry,

I'm confused by the "crop factor." I understand the sensor is smaller than the conventional 35 mm, but does the crop factor actually increase the magnification of the lens (i.e. bring subject closer) or does it simply reduce the field of view to what a longer lens would provide? I did a lot of research when I was looking for a DSLR, but never really understood that point. As an aside, I was coveting the 20D, but cost new was prohibitive. Finally found a friend who was selling her 10D backup to upgrade to a 5D. Got it with the same 100-400 lens you recommended in another post. I've got more camera than my ability warrants, but hopefully I'll grow into it!

[Weasel]

Originally posted by Steve Kendrot:
Jerry,

I'm confused by the "crop factor." I understand the sensor is smaller than the conventional 35 mm, but does the crop factor actually increase the magnification of the lens (i.e. bring subject closer) or does it simply reduce the field of view to what a longer lens would provide?

Kinda both?  It doesn't physically bring the subject closer, but because it reduces the field of view (crop), it gives you the view a longer lens would provide.  It really is easier to demonstrate than describe. This one always gives me a headache...  

[Steve Kendrot]

I guess I think in terms of power... If 50mm  aproximates what the human eye sees, then 100 mm equals 2X and 400 mm equals 8X. The crop factors increases the 400mm to 620mm, but does it increase the power to 12X? I don't believe so according to my understanding. It would be like taking a pair of 8x binos and taping the objective lens to restrict the view to that of a 12X bino. Smaller field of view, but the critter doesn't look any closer (though it does fill up more of the frame because the frame is smaller). Do I have it right?

[Weasel]

Yes!!!  

[jcsnapshot]

Hope this very quick drawing helps. The blocks on the left are supposed to be the same size. Top right is 35mm film. Bottom is digital sensor. I think this is what Jerry was talking about when he said it was easier to draw, than explain.

 

[Steve Kendrot]

Thanks for confirming my thoughts Jerry. Its a good marketing ploy, but I really don't see the "advantage" on the telephoto end if it doesn't increase power. The loss on the wide angle side is a more important loss. I bought a Canon EF 28-105 1:3.5-4.5 II USM as an every day lens. I just couldn't afford the IS 24-135 lens you said you use as much as I would have liked it.

[jcsnapshot]

If I put my N80 (35mm), and D100(digital) on a bracket on the same tripod, both with 50mm lenses, and focus on the same subject, the subject in the image created with the D100 will roughly be half again as big as the subject created by the N80. Wouldn't that mean that the magnification increases on the digital?

[Weasel]

Originally posted by Steve Kendrot:
Thanks for confirming my thoughts Jerry. Its a good marketing ploy, but I really don't see the "advantage" on the telephoto end if it doesn't increase power. The loss on the wide angle side is a more important loss. I bought a Canon EF 28-105 1:3.5-4.5 II USM as an every day lens. I just couldn't afford the IS 24-135 lens you said you use as much as I would have liked it.

You get the same image size as if you were using the longer lens, which essentially places you closer to the subject.  If you have a deer at 100 yards and you use a 400mm with a film body, then put the 400 on the digital with the crop facter, the image size would be as if you crept another 30 or so yards closer to the deer with the film body, so there is definitely an advantage on the long end with the crop factor.

I don't have the 24-105 IS.  Can't afford it.  I have the 28-135 IS.  Which I bought used.

[Weasel]

Originally posted by jcsnapshot:
If I put my N80 (35mm), and D100(digital) on a bracket on the same tripod, both with 50mm lenses, and focus on the same subject, the subject in the image created with the D100 will roughly be half again as big as the subject created by the N80. Wouldn't that mean that the magnification increases on the digital?

The crop factor would make it appear so, yes.  It's not really true magnification according to the experts.  (I want to make it clear that ain't one of them).  The fact is, the subject is larger on the digital sensor and that's all that matters.

Am I right?

[Steve Kendrot]

I guess so... starting to make sense. If the same image is captured with the same lens on a  piece of 35mm film and a digital sensor. When the image from each is "projected" onto a 8x10 piece of paper, the digital sensor will print larger because it captured a smaller area around the target compared to the 35mm. Now I get it....Do I?   :rolleyes:

[jcsnapshot]

Jerry, hope I didn't come off as a smarta$$. It just seemed to me that maginification actually increased, but your last post makes more sense. I am far from an expert     Just seemed logical to me.

Yup Steve, that is it. I won't even get into the fact that when printing 8x10's from 35mm slides or negs, you lose about an inch on each side of the 10 inch, because 8x12 is the "natural" enlargement from 35mm. LOL Sorry about that.

[Weasel]

Originally posted by jcsnapshot:
Jerry, hope I didn't come off as a smarta$$.

Not at all!  This is a difficult concept to explain.  I think between us all we explained it.  Kinda...    :D

[Weasel]

Originally posted by Steve Kendrot:
I guess so... starting to make sense. If the same image is captured with the same lens on a  piece of 35mm film and a digital sensor. When the image from each is "projected" onto a 8x10 piece of paper, the digital sensor will print larger because it captured a smaller area around the target compared to the 35mm. Now I get it....Do I?    :rolleyes:  

Yes!!  

[Phil Magistro]

There's a good explanation of crop factor here -

 http://www.millhouse.nl/digitalcropfactorframe.html

[Jason R. Wesbrock]

Last week I upgraded from a Canon Digital Rebel to a 20D. That's an impressive piece of equipment! The only thing I'd change is to make is compatible with an inexpensive wireless remote (like my Digital Rebel is). Why Canon doesn't do that I'll never understand.

[Weasel]

Originally posted by Jason R. Wesbrock:
Last week I upgraded from a Canon Digital Rebel to a 20D. That's an impressive piece of equipment! The only thing I'd change is to make is compatible with an inexpensive wireless remote (like my Digital Rebel is). Why Canon doesn't do that I'll never understand.

Ooh.  Shoulda waited. Want wireless? This just announced today:  http://www.robgalbraith.com/bins/multi_page.asp?cid=7-7891-8214