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Messages - epsiloneri

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286
EOS Bodies / Re: The 60D Needs AF Microadjustment
« on: December 15, 2010, 02:25:33 PM »
Ok, so I have a few questions for neuroanatomist:

1) You now have a 5D2 in addition to your 7D. Have you retested your lenses with you new body? Do you find a constant offset from your adjustments for 7D? In principle I think you should be able to, and that would mean it would be sufficient to only measure one lens, say a sensitive one like your 85/1.2L, and then apply the difference between the MA for that lens and 7D and MA for 5D2 to all other lenses to have the calibration to 5D2 without having to remeasure all lenses. I don't know if this works in practice, however, as it assumes the MA scale is linear which it may not be (I don't know). It would therefore be interesting to read your experience!

2) Have you tried to use an interference image on a computer screen as a focus target instead of the LenAlign Pro? I mean as detailed in this post by Keith Cooper.

3) Have you attempted to check whether there is a distance dependence to the optimal MA for your lenses? I've seen recommended distances for measurements to be 25-50 times the focal length, but I'm curious how well the adjustment works for other distances as well.

Something that would simplify MA would be to have a "calibration wizard" where you 1) autofocused on a target and 2) set the optimal focus manually (using live view). The camera should then be able to compute the corresponding MA itself. (This could even be generalised to MA as a function of distance.) This would ideally decrease the time required for a lens calibration to a few minutes instead of an hour.

Another thing I would love to see is focus bracketing. It was available on my Canon G2, but I haven't seen it since.


287
In mjardeen's defense, the OP contradicts itself.  He does put out the suggestion of the 16-35, but also says he want's something wider than his 15-85.

I don't find it contradicting to compare the IQ of two lenses of different focal length ranges. MTF, colour aberration, and vignetting, are all examples of things you can compare. You can even compare the IQ of a 14mm/2.8 lens to a 400mm/2.8, even if there of course are very few situations where you can substitute one for the other.


288
Everything I've read says the Tokina 11-16mm f2.8 is the best APS-C ultra-wide lens out there.

"Best" in some areas, but not all. Looking at the review you linked to, the Canon seems obviously sharper in the corners already from f/3.5, while the Tokina becomes similarly sharp only at f/5.6 (and is very soft at f/2.8 ). The MM of the Tokina is very low, and the chromatic aberrations not very well controlled. I agree that the light gathering power and lower price makes the Tokina a very attractive option, but not best in all areas.

289
Lenses / Re: 24-70 mm f/2.8
« on: December 12, 2010, 08:17:01 PM »
I know this is also probably not what you want to hear, but I don't think either is a very good match for your 7D. It of course depends on what you are looking for in a new lens, but if it is light gathering power, I would suggest the EF-S 17-55/2.8 IS instead. Both lighter and cheaper than the EF 24-70/2.8L, but just as good, if not better, IQ. Also a more useful focal range, IMHO. 24mm is not really wide enough on APS-C (try it on your current lens). No weather sealing though, if that's a big deal for you.

290
I don't know how the EF-S 10-22mm compares to the EF 16-35L on APS-C in the focal range where they overlap, but overall, the 10-22mm is very well regarded and I don't think you would disappointed by it. There are plenty of professional online reviews you can consult if you're uncertain.

If you're anyway planning to stay with APS-C for some time, I think it's a bad idea to insist on FF lenses and not take advantage of the EF-S format at the wide end (lighter, cheaper). My advice is to sell your EF-S lenses when/if you make the APS-C to FF switch. You will not lose that much money, and the money will be well spent. There is no current Canon FF lens on the APS-C able to compete with the EF-S 10-22mm at the wide end.

291
EOS Bodies / Re: Canon EOS 7D Mark II - sensor
« on: December 04, 2010, 03:12:50 AM »
Quote
if I wanted to shrink my 300 F4's length, I'd shoot it on my film rebel.

Ha! Ha! I think we are all getting spoiled by the extra reach of the 1.6 crop. I'm certainly not interested in going backward either.

I don't get this. The way things are going, in the future the price of a camera will be set by its optics, not its sensor. If you're anyway using a FF lens, why not let the sensor cover the whole available field? Your "crop" camera will be equivalent to cropping the image of the FF (hence the name "crop" camera). Is it the larger magnification of the view finder on crop cameras you will miss? Concern about many pixels taking space while going unused? Perhaps Canon could do like Nikon and have an "APS-C" mode with in-camera cropping.

Edit: Here's and idea. What would you think of a 3.2x crop camera then? You'd have twice the reach compared  to 1.6x!

292
EOS Bodies / Re: Changes to dials on Canon 5D and 7D
« on: December 01, 2010, 06:34:09 PM »
I think it's a nice addition; it happens to me from time to time that the dial moves accidentally, resulting in a lost shot. I wouldn't spend $100 on it, however. For some professionals it could perhaps be worth it.

293
Lenses / Re: 24 - 70 f/2.8 L : When Is The New Version Expected?
« on: November 29, 2010, 12:25:25 PM »
I also tested both 17-55 2.8 IS and the 24-70 2.8 on my 50D. 3 people looked at the photos and the 17-55 produced a ted better photos. So until Canon does not come with a better lens for FF I will not switch to FF

But how do you know the 24-70/2.8 does not produce better photos on a FF than the 17-55/2.8 on the 50D?

294
Lenses / Re: 24-840mm zoom
« on: November 23, 2010, 03:01:03 AM »
I want a Canon 10-5000mm F1.2 L IS USM

In principle, you could build such a lens. Unfortunately it would have to be >4m in diameter.

The longest lens I've used was a 123000mm f/15 IS prime :P It wasn't either very portable, though (and didn't have an EF mount). The longest lens I've connected to an EF camera was an 11000mm f/11 prime. Biggest IQ limitation was the atmosphere. I probably don't have to add that those lenses dwarf even an EOS 1Ds mkIII.

295
Lenses / Re: 24 - 70 f/2.8 L : When Is The New Version Expected?
« on: November 22, 2010, 01:16:44 PM »
The most recent posts are:

http://www.canonrumors.com/2010/10/canon-ef-24-70-f2-8l-ii-patent/
http://www.canonrumors.com/2010/10/lenses-in-2011-cr2/
http://www.canonrumors.com/2010/09/ef-24-70-f2-8l-replacement-cr2/

Standard expected announcement time has been in about "half a year from now" for the past year(s). Expected price in the UK £1400 based on sheer speculation combined with comparison on mark-ups for non-IS to IS versions of other lenses. Could be quite wrong, but should be within £1k-2k with high confidence.

296
Lenses / Re: 100-400 Replacement
« on: November 22, 2010, 12:52:54 PM »
The only time that I've been in a rain forest, I can't recall having had need of a lens faster than 5.6.

Rain forests are often surprisingly dark, even at noon. Light conditions can also be difficult due to tree crown openings that let through spots of harsh sunlight, resulting in very contrasty conditions. Flash can actually be a good option, unless you're hunting easily disturbed animals.

297
Lenses / Re: EF 24-105 f/3.5-5.6 IS Patent
« on: November 22, 2010, 12:34:40 PM »
I wonder why it's not called 25-102mm, or even 25-100mm, since that seems to be the focal length range (for focus at infinity, I assume).

"Pojitiburidotaipu zoom" should be "Positive ride type zoom".

Ah yes, I wondered about that too. Not that "positive ride type zoom" is much more illuminating (to me).


298
EOS Bodies / Re: March, Lenses & Stuff
« on: November 20, 2010, 02:06:16 PM »
Thanks Kyle, for the nerdy summary of dSLR lifetimes. Posts like yours are a zillion times more interesting than the "why I prefer Canon/Nikon over Nikon/Canon" posts.

299
EOS Bodies / Re: No 1Ds IV? [CR1]
« on: November 10, 2010, 02:59:08 PM »
A long lens actually need a bigger mirror due to the narrower object angle. You can try to  draw it out yourself. or you can try to read some of the manual of film SLR in the 60's, they do mention the above effect.

Hmmm.... I'm not convinced. Wouldn't you get limb darkening unless the mirror reflected the full beam? Unfortunately I don't have any camera manuals from the 60's lying around  :) Perhaps you can direct me to a more accessible source for information?

300
Of course, Pros have a way to recover their equipment cost, whereas the amateurs, don't. What could be used as a business write-off for Pros, amateurs don't. Even more, since Pros can get their equipments' cost from jobs, amateurs don't.

I agree, but the point was that the equipment often are more than tools for the amateur. If the impact of scratches or dust is insignificant for its function, it is of no consequence for a pro; but for an amateur, they can be a major issue.

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