Multiplication facor of focal length in digital EOS camera

[b@s]

Has anyone here heard of a way to deal with the 1 point 6 something multipiflication factor of the focal length of the lens when switching to (in my case) the EOS 10D? Apart from going to a full frame sensor camera? I want my 20mm to be a 20mm instead of a 32mm lens, and I dont want to spend the 2 grand for a 14mm...

This would have to be dealt with optically by using the inverse of an extender, which will have to incorporate some sort of optics to stay clear of the mirror in the camera.

I'm curious..

[HJMinard]

The short answer: no. Outside of buying a full frame sensor body there is no way to make your 20mm images look the same as they did when the 20mm was attached to your 35mm camera. Fortunately, there are lenses out there (Sigma 12-24; upcoming Tamron 11-18; Tokina 17mm) that get you wide at a relatively reasonable price.

[jbradc]

There is no way around it. Any lens on a Canon 10D, 20D or Drebel will have a 1.6 crop factor and on the 1D MkII will have a 1.3 crop factor. If you need true a ultra wide lens try the Sigma or Tamron 14mm F2.8 (22.4 with 1.6 CF) both are high quality optics for under a grand or the new Canon 10-22mm (16-35 with 1.6 CF). And Tokina just anounced a 12-24 F4 (http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=360349&is=REG) for about $500.00. Of course you could always get a 1Ds or 1Ds MkII, both have a full frame sensor but it will cost you.

[b@s]

Thanks guys for confirming what I already feared.. I'll have to think of another solution or go with the flow. Another thing I found is that the EF-S lensed (s for short??) i.e. the lenses specially made for the 20D and 300D do not fit on the 10D, unless you are willing to put a saw and/or file to the mount on the lens to adapt it to fit the 10D. Those considering this see bob atkins story first and read what and why at:

http://www.bobatkins.com/photography/tutorials/efs-10d.html

I think I'll just go and make some photos with what I have.

[HJMinard]

I think I'll just go and make some photos with what I have.

Hallelujah ... couldn't have said it better myself.

After awhile, you probably won't even notice the difference. Some of us - particularly those of us who enjoy wildlife photography - actually prefer the 1.6 factor.

[FlyingPete]

Thanks guys for confirming what I already feared.. I'll have to think of another solution or go with the flow. Another thing I found is that the EF-S lensed (s for short??) i.e. the lenses specially made for the 20D and 300D do not fit on the 10D, unless you are willing to put a saw and/or file to the mount on the lens to adapt it to fit the 10D. Those considering this see bob atkins story first and read what and why at:

http://www.bobatkins.com/photography/tutorials/efs-10d.html

I think I'll just go and make some photos with what I have.

I don't know about everywhere else in the world, but the internet auction sites have a heap of the 18-55's for sale, some quite cheap, so that hack might be worth a shot, haven't heard of anyone screwing it up yet. Wouldn't use the hacked lens on anything other than a 1.6 SLR, as there will probably be vignetting.

And that folks is 500 posts from me!

[picture-this]

Remember 1.6 is the crop factor, it doesn't change the magnification just how much of the shot fits in the frame.

[tim]

Remember 1.6 is the crop factor, it doesn't change the magnification just how much of the shot fits in the frame.

Thank god someone understands that it's a crop factor not a magnification factor!

Solution 1: stand further away.
Solution 2: buy a wider lens.
Solution 3: if solution 1 or 2 don't work, buy a camera with a full frame sensor.

[pcasciola]

Like HJMinard, I actually prefer the 1.6 factor for sports as well as wildlife. It may not be magnification in the purest sense of the word, but depending on the 1.6x camera you choose, it's the next best thing. I talked to someone on FM who owns a 20D, 1D Mk II and 1Ds Mk II, and using the same Canon 500mm F/4L on each body from the same distance on a tripod, the 20D produced more detail and the largest image (pixel for pixel) than either of the full frame cameras on the same object. So it all depends on what your definition of magnification is.

[Tom W]

I don't know about everywhere else in the world, but the internet auction sites have a heap of the 18-55's for sale, some quite cheap, so that hack might be worth a shot, haven't heard of anyone screwing it up yet. Wouldn't use the hacked lens on anything other than a 1.6 SLR, as there will probably be vignetting.

And that folks is 500 posts from me!

Here's a hack that someone claims to have done. I can't read the text, but the images tell a bit of a story:

http://avbuzz.com/new_home/w/200501/model/yesun0105/yesun0105.php

[b@s]

Once again, thanks for your replies, as for multiplication- and cropfactor, neither really happens its just the sensor which is smaller than a 35mm frame, hence 'using' (sensing) only part of the image projected by the lens. Cropping is what one does in Photoshop I think.

Multiplication factor is the term which comes to mind when one reads the manual for the 10d; translated from Dutch (my manual is in Dutch) "because the size of the sensor is smaller than the normal 35mm filmformat, the EF-lens will have a tele-effect equal to 1.6 times the indicated focal length".

Multiplication factor is the term which also comes to mind when I see the price tag of lenses which will give me a 20mm effective focal length image on the 10d. The factor then is about 4.0 (times the price I paid for the 20mm versus the price for the 14mm EF).

But it seems Tom W has found a site where someone shows he fiddled around and found out that u can adapt the lensmount by replacing the inside plastic ring (See the photo's on the site).
Tom, thanks a lot!! I now need to find someone to translate the text.. neither I can read the text but the photo's are clear enough. Maybe I can get the EF-S 10-22..
But for now I'll go and make photo's

[tim]

Once again, thanks for your replies, as for multiplication- and cropfactor, neither really happens its just the sensor which is smaller than a 35mm frame, hence 'using' (sensing) only part of the image projected by the lens. Cropping is what one does in Photoshop I think.


Crop factor is the commonly used term to indicate the sensor isn't the same size as a 35mm frame. It's probably not accurate but it's the term that's used.

[indpndnt]

Too technical for me. Does that mean that my picture will actually be cropped tighter than what I see through the viewfinder?

[tim]

Nope, what you see thru the viewfinder is what the picture will look like on the PC, give or take 5%. If you put the same lens on a film camera you'd get a wider view than on a 10D/20D/300D - that's the "crop factor" coming into play. The digital cameras just ignore the outsides of the picture, whereas the film camera would record them.

[Bodog]

Thank God!. I was afraid this was going the turn into another X-factor thread!! Stand down, CDS... ;)

[Hellashot]

Has anyone here heard of a way to deal with the 1 point 6 something multipiflication factor of the focal length of the lens when switching to (in my case) the EOS 10D? Apart from going to a full frame sensor camera? I want my 20mm to be a 20mm instead of a 32mm lens, and I dont want to spend the 2 grand for a 14mm...

This would have to be dealt with optically by using the inverse of an extender, which will have to incorporate some sort of optics to stay clear of the mirror in the camera.

I'm curious..

Nope!

[ScottE]

The 1.6 multiplication is both an advantage. I do a lot of wildlife photograph and love the fact that my 500 mm lens now acts like it was 800 mm without having to add a teleconvert and lose a stop of lens speed.

If you have a D Rebel or 20D and your favorite 35 mm lens is a 16-35 mm, the solution is to resign yourself to buying one of those new 10-22 lenses that will only work on those two cameras.

If you have a D30, D60 or 10D you will have to look at third party manufacturers like Sigma, Tamron or Tokina for a 12-24 mm zoom.

[Akreager]

1.6 sucks for wide angle but there is a decent option. The 15mm fisheye. It is a little over 500 bucks but a very nice lens. If you have Photoshop you can correct the perspective and make it non fisheye like. If you do not have PS.....

[CyberDyneSystems]

Thank God!. I was afraid this was going the turn into another X-factor thread!! Stand down, CDS... ;)

... I've been waiting to see myself,... :rolleyes: