Does the 1.4 II extender effect depth of field along with light intensity?

[Abdulrahman Aljabri]

I am thinking about getting the 45tse and using it plus a 1.4 extender. Using the extender will cause exposure to go up by one stop, so I either have to increase the shutter by one stop (ex 1/20 down to 1/10) or in studio increase my strobe power 1 stop to compensate, but what happens to depth of field in the process?

Does depth of field increase like going up from 2.8 to 4.0 or the extender only affect light intensity? If I were to use the 45tse + 1.4e (eqiv 63mm) at f2.8 will the results match the 24-70L zoom set at 63mm at 2.8 in depth of field and relative intensity of blurring?


I hope I was clear and thanks in advance!

[ErikKaffehr]

Hi,

I have not done the math but I would expect DOF to stay the same as for unextended lens at f/2.8 you essentially stop down one step that compensates for the 1.4x extension.

Are you sure that the 1.4x extender works with your 45 TSE? They used to be intended for telephoto lenses!

Best regards
Erik

[Canon Bob]

Abdul,

The EF1.4x will fit and work with the TS-E45 but your minimum aperture will be f/4.
DoF will be the equivalent of 63mm f/4....DoF is a function of aperture and magnification.

Bob

[Abdulrahman Aljabri]

Are you sure that the 1.4x extender works with your 45 TSE? They used to be intended for telephoto lenses!

I use my 24tse with the extender without much of a problem, though it might be costing me too much optical quality.


This review from amazon has opened my eyes to something I did not realize before today:

http://www.amazon.com/review/R9P3Q7JPQWBGK/ref=cm_cr_dp_cmt?ie=UTF8&ASIN=B00009XVCX&nodeID=172282#wasThisHelpful

Although officially unsupported, we often see people say that TS-E45mm works fine with 1.4x and 2x teleconverters online. I think what they mean is merely that the teleconverter fits without a mechanical problem. However, this needs a caveat. If the lens is shifted while on a teleconverter, the lateral chromatic aberration worsens dramatically. Other aberration probably worsens, because focus is also not very sharp. Tilt is not as bad in this regard. Simultaneous tilt and shift is also very bad. So, if you use this lens with a teleconverter, you should limit the lens movement to a small tilt only. Since the movement is limited by the image quality, the limitation is not absolute, but certainly limits the usability of this lens with a teleconverter. Also, with a 1.4x teleconverter, I see a noticeable drop in image contrast."

I read before that people were using the 1.4 extender with the new 24tse II, I wonder how that is working out?

The EF1.4x will fit and work with the TS-E45 but your minimum aperture will be f/4.
DoF will be the equivalent of 63mm f/4....DoF is a function of aperture and magnification.

Disappointing but that really clarifies things

[Kirk Gittings]

Abdul,

I use the 1.4 II on the 24LII T/S. When I first read about using the 1.4II on the 24II here, I tested it against my Olympus 35PC, and against the 24 itself on a 5DII. I was astonished that the combination worked so well. The Olympus was a superb little lens in its day, but the 1.4/24 combo kicked its butt. The only issue really I have noticed with the 1.4 on the 24 is slight increase in barrel distortion. Resolution is good fully shifted-only slightly less than the 24 lens alone and I have not noticed an increase in CA. I donated the Olympus to a university photo program and haven't looked back. It is a very usable combination.

[Abdulrahman Aljabri]

Abdul,

I use the 1.4 II on the 24LII T/S. When I first read about using the 1.4II on the 24II here, I tested it against my Olympus 35PC, and against the 24 itself on a 5DII. I was astonished that the combination worked so well. The Olympus was a superb little lens in its day, but the 1.4/24 combo kicked its butt. The only issue really I have noticed with the 1.4 on the 24 is slight increase in barrel distortion. Resolution is good fully shifted-only slightly less than the 24 lens alone and I have not noticed an increase in CA. I donated the Olympus to a university photo program and haven't looked back. It is a very usable combination.

Impressive. Compared to the 24ts-e MKI the MKII is so much better! I really look forward to buying it one day. I need, however, enough interior work to justify such investment. For the time being the MKI will have to do. I just hope the 45ts-e does not suffer from the extender as much as the amazon reviewer above reports in his review.

[01af]

DoF is a function of aperture and magnification.

That's a common misconception. For a given camera, depth-of-field basically is a function of distance, focal length, and aperture.

Distance and focal length cancel each other out (for practical intents and purposes) only when DOF is small in relation to the distance, i. e. with telephoto lenses (at long distances) and in macro photography (at large magnifications). They do not cancel each other out in general.

I am thinking about getting the Canon TS-E 45 mm and using it plus a 1.4× extender. [...] but what happens to depth of field in the process?

Depends on what you're trying to achieve. Will you use the extender to increase magnification (at the same distance) or to increase distance (for the same magnification)?

If I were to use the TS-E 45 mm + 1.4× (= 63 mm) at f/2.8, will the results match the EF 24-70L zoom set at 63 mm at f/2.8 in depth-of-field and relative intensity of blurring?

No. They will basically match the results of the 24-70 mm zoom lens, set to 63 mm and f/4. I said 'basically' because the actual results may still differ due to differences in the lens designs and residual aberrations.

Regarding aberrations ... tele converters usually work best when used to make long lelephoto lenses even longer. Typically they do not go very well with wide-angle or standard lenses. However shift-and-tilt lenses have an increased exit-pupil-to-image distance (to make room for the shifting and tilting mechanisms) so they will work somewhat better on tele converters than regular lenses of the same focal length would—at least as long as they're neither shifted nor tilted. When shifting or tilting, image quality on a tele converter may or may not break down, depending on the particular lens, converter, and degree of lens adjustment. If someone is getting good results using a TS-E 24 mm on a 1.4× converter it doesn't necessarily mean that results will also be good with the TS-E 45 mm lens on a converter. in any case, it means using the equipment outside the intended scope of application. So try it out before purchasing!

[Bart_van_der_Wolf]

That's a common misconception. For a given camera, depth-of-field basically is a function of distance, focal length, and aperture.

Distance and focal length cancel each other out (for practical intents and purposes) only when DOF is small in relation to the distance, i. e. with telephoto lenses (at long distances) and in macro photography (at large magnifications). They do not cancel each other out in general.

IMHO one of the, if not the, best treatments of the subject can be found on Paul van Walree's website from which I quote (emphasis is mine):

A final wrap-up of the issue of a depth of field comparison at a constant image magnification and F-number is the following:

1.When for both lenses the object distance is much smaller than the hyperfocal distance, the depths of field are essentially the same.
2.When one or both object distances are not small with respect to the hyperfocal distance, the lens with the shorter focal length brings more depth of field.
3.If the lens designs are the same, points 1 and 2 are the whole story. If the lens designs (pupil magnifications) differ, point 2 still holds but point 1 must be reconsidered. Depending on their design either one of the lenses in the comparison can yield more DOF.

He also correctly points out that the different shooting distances will result in differences of perspective.

Cheers,
Bart

[01af]

IMHO one of the, if not the, best treatments of the subject can be found on Paul van Walree's website ...

In my opinion, it definitely is the best. As far as I can tell, it's the only general text on depth-of-field on the Internet which is free from errors and misconceptions.