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-   -   Canon 14mm L or Tokina 11-16mm for Steadicam on 60D/7D? - Hyperfocal Distance Query!! (https://www.dvinfo.net/forum/canon-eos-crop-sensor-hd/485384-canon-14mm-l-tokina-11-16mm-steadicam-60d-7d-hyperfocal-distance-query.html)

Josh Fung September 27th, 2010 09:40 PM

Canon 14mm L or Tokina 11-16mm for Steadicam on 60D/7D? - Hyperfocal Distance Query!!
 
Hi Guys,

Patrick Moreau mentioned his preference for the 14mm + 7D combo in this video

stillmotion’s guide to lenses for weddings and events | stillmotion


I found this very interesting so I googled hyperfocal distance (not knowing what it meant). So I got the formula for calculating it..

Hyperfocal distance = f ^2 / Nc where f = local length .. for a 14mm prime its 14.
N is aperture... c is a constant = 0.018 for APS-C and 0.029 for Full Frame.
(more details here: Hyperfocal distance - Wikipedia, the free encyclopedia)

So basically the relationship is wider the focal length is, and more stopped down the lens is and the small the sensor is .. the smaller the hyperfocal distance.

My question is.. for flying a Crop sensor camera on the merlin.. do you multiply the focal length to equate the field of view on a crop camera? what about for EFS lenses e.g. 11-16mm Tokina, do you multiply it out by 1.6 then calculate the hyperfocal distance?

Patrick mentions 7D + 14mm combo gives a 3 feet or 0.9meter hyperfocal distance, which means objects at 0.45m or beyond will be in focus. Hence how sharply focussed his videos are on the steadicam.

I tried calculating using the formula above, and plugged in f= 14... c = 0.018 and N = f12.0, which gives 0.9m or 3 feet as Patrick said.

Am I doing this right?

I guess the main motive for my question is, which lens to get shorter hyperfocal distance while keeping the iris as wide open as possible (for low light shoots without cranking up ISO)... considering the price difference as well... this Tokina at 600 USD, and the Canon 14mm f2.8 II L at around 2000 USD... it would be worth finding out..........

Considering Both are rectinlinear i.e. not fish eye i.e. straight lines are straight..... 14mm we crop out the distortion at the sides (compared to a full frame image) where as Tokina have some distortion as well at its wider ranges.

Any input is appreciated. Thanks!!

Charles Papert September 28th, 2010 01:30 AM

If I understand the question correctly, it is whether or not one has to make adjustments to the calculation for a crop factor lens when calculating hyperfocal. The answer is no. 14mm is 14mm, whether the lens covers full frame or not. Field of view is not part of the equation.

Both lenses should deliver equivalent field of view on the 7D. At 14mm on the Tokina you will nominally see the same hyperfocal as a 14mm Canon. You may notice that I qualified both those statements, due to the fact that differences in lens design will likely have a certain amount of real world bearing and there may be slight differences in the above factors.

Josh Fung September 28th, 2010 02:46 AM

Hi Charles, thank you very much for your response.

so in essence, Tokina's 11-16mm and Canon 14mm can both get very similar hyperfocal distances if used on a crop sensor if Tokina's focal length is set to 14mm and aperture of both are set to the same...?

Therefore, as far as focus is concerned on the steadicam, the Tokina seems to be the better choice for its price.

Mike Peterson September 28th, 2010 12:45 PM

The Tokina is a fantastic lens

Rich Ryan September 28th, 2010 01:17 PM

Take a look at Hyperfocal Distance and Depth of Field Calculator - DOFMaster there some tables, articles and best of all the online calculator. I use it all the time to look at depth of field and hyperfocal distance.

Jonathan Shaw September 28th, 2010 03:41 PM

Also remember that the Still motion guys are sponsored by Canon,

Canon 14mm L great lens, Tokina, great lens but cheaper

Charles Papert September 29th, 2010 03:53 AM

Josh:

Yes--again, focal length is a fixed variable--what changes with crop sensors is field of view. Lenses don't "know" what camera they are attached to; the optical functions remain the same.

Glad to see folks are getting into DOF tables, hyperfocal etc. Only six months ago I was coming up against resistance against all this from those who had always used the "set it on infinity and shoot" philosophy that came with the small format camcorders.

Nigel Barker September 30th, 2010 01:16 AM

Quote:

Originally Posted by Jonathan Shaw (Post 1573767)
Also remember that the Still motion guys are sponsored by Canon,

Canon 14mm L great lens, Tokina, great lens but cheaper

The manual Samyang 14mm F2.8 lens (also sold under the names Rokinon & Bower) is even cheaper & is very well spoken of in reviews.
http://www.bhphotovideo.com/c/product/698923-REG/Bower_SLY14MMF28C_14mm_f_2_8_Ultra_Wide.htmlSamyang 14mm f/2.8 IF ED UMC Aspherical - Full Format Review / Test Report

The lack of auto-focus or electronic aperture control would be no drawback on a Steadicam.

Josh Fung October 6th, 2010 04:53 AM

Hi Guys, after comparing tokina 11-16 vs canon 10-22 instore, I decided to go with the 10-22 instead. for the following reasons I posted in a 60D quick review below. Thanks to all for your help and advice, its greatly appreciated!

http://www.dvinfo.net/forum/canon-eo...-dislikes.html

- Canon 14mm f2.8 L - no doubt the best lens for steadicam if budget is not an issue. Tremendously sharp, low distortion, True L class lens. But weighing the price / Return on Investment / value, this seems to be ultra luxury item, which leaves two real contenders which is the below two lenses
- Tokina 11-16mm f2.8 - having owned this from my 7D days, awesome sharpness, low light performance, build quality. But what really ticked me off was the distortion at 14/15mm its really stretched badly at the sides. At the pretty much the same price on the 2nd hand market as the 10-22mm it was a close call, but I chose the 10-22mm EFS from Canon for the following reasons
- Canon 10-22mm f3.5-f4.5. - I pretty much bought this lens primarily for steadicam. at 14mm this has the same hyperfocal distance as Canon 14mm f2.8 L. Since on steadicam, everything need to be stopped down anyway to about f11 at 14mm for a 1m hyperfocal for a crop sensor camera, the extra half stop of light of Tokina wasn't that much of an advantage. After testing and comparing the distortion at 14/15mm between this and Tokina, i have to say Canon is the marginal winner.
- Compared to 5D2+16-35mm combo: My 60D + 10-22mm is alot lighter than the 5D2 combo, having shorter hyperfocal distance than the 5D2 at 24mm, this allows for slight better low light performance on a steadicam.
- Light weight!!! my 60D + 10-22mm combo is only 1.16kg. Compared to 1.4-1.5kg of the 5D2 + 16-35mm combo. This means I lose one mid weight on the nose, and on mid weight on the spar of the merlin. That is alot of counter weight reduced, which improves long merlin operation sessions.

Andy Wilkinson October 6th, 2010 05:16 AM

Canon 10-22mm versus Tokina 11-16mm
 
Hi Josh. I agree with you that, for certain needs, the Canon 10-22 is better than the Tokina 11-16 (which is why I bought the Canon). Just posting my comparison here between these 2 lenses as it may help others with this often difficult choice.

CanonWideAngle

Both are fabulous lenses in so many ways and which is "best" depends on so many things/will be different for different people.

For sure, the lighter Canon 10-22 works great on the Merlin Steadicam (with a 7D) as I've posted about elsewhere on here/on YouTube etc. I also like knowing that the Canon 10-22 is much more likely guaranteed to work on future (albeit cropped body) Canon bodies (....for when a say, non-aliasing 9D eventually come's out - here's dreaming!!!), something which is not always taken into consideration when buying 3rd part lenses with chips in them (that have been backward engineered if I've understood this aspect correctly).

Randy Panado October 8th, 2010 08:24 AM

Quote:

Originally Posted by Charles Papert (Post 1573918)

Glad to see folks are getting into DOF tables, hyperfocal etc. Only six months ago I was coming up against resistance against all this from those who had always used the "set it on infinity and shoot" philosophy that came with the small format camcorders.

I believe we had a conversation on that (linked here : http://www.dvinfo.net/forum/canon-eo...eadicam-2.html) and I take your comment in offense when you make that sort of blanket statement. Just because we set our lens on infinity and shoot at f/8 outdoors or f/4 indoors and stay within the focus range doesn't mean we don't understand hyperfocal distance. You fail to mention that some of those who use the infinity technique also understand how far to be from the subject and doing so paints them in an incompetent light as steadicam operators. From the linked conversation, I don't see any resistance going your way. Quite the opposite, I actually said I would try out your method and see how the results were. Also, the fact that I alude to the surprising range of focus I get with the 11-16 does show that I'm not "setting it and forgetting it".

I highly respect your opinion in regards to all things steadicam so it's a bit disheartening to see that statement coming from you. If you're referring to some other tete-a-tete you had with another member on the boards, my apologies but again, such a broad blanket statement is a bit unfair.

Cheers.

Charles Papert October 8th, 2010 11:59 AM

Hi Randy:

I wasn't making a blanket statement (note that my use of "all" in there referred to the various principles of optics I listed, not everyone who sets their lens at infinity). I suppose I could have said "some of those" to make it less inclusive, but I was referring to some voices who had specifically indicated that they had always done it this way, and with most people migrating from 1/3" cameras to DSLR's within the past year, I thought it a fair assumption. Along these lines, may I suggest that your statement "Just because we set our lens on infinity and shoot at f/8 outdoors or f/4 indoors and stay within the focus range doesn't mean we don't understand hyperfocal distance" was itself somewhat "blankety", as there are undoubtedly a percentage of users in that "we" group who don't yet fully grasp and/or apply depth of field principles, or at least there were earlier this year!

Ultimately, I don't think it wasn't that particular thread that prompted my statement. I know that there were others prior to that as I can sense some exasperation in my tone in post #27. While I'm predominately based here at DVI, I do read and occasionally post on other boards and I do recall hearing the statement, "well, it's always worked for me so I'm just going to keep doing it" coming from those who had only recently starting working with large sensors.

Since the popularity of these types of cameras is largely based on the shallow depth of field look, I just think it's a shame that many users are unable to take advantage of this when using Steadicam. There have been threads that ask "what is the best lens for Steadicam" in regards to these cameras, and it's a shame to think that the answer is based not in a creative choice but a practical one: which lens will hold the deepest focus in a set-and-forget environment.

Andrew Petrie October 10th, 2010 10:06 AM

I just got the Tokina 11-16mm, and I'm very happy with it so far. For the price, and the fixed f2.8 I don't think you can go wrong.

Mike Peterson October 10th, 2010 09:02 PM

Tokina.Excellent lens.

Norman Pogson October 11th, 2010 08:40 AM

I have the Tokina also and it is great value for money. The thing about wide angle lenses is that they have a very deep depth of field, especially when you stop down to f8 to f16. I mostly focus a third into the scene and can usually get away with pretty much everything in focus.


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