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Messages - East Wind Photography

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286
Lenses / Re: Lens sharpness and distance from subject
« on: April 29, 2013, 09:16:02 AM »
That's because the test chart is designed to reveal the limits of the lens at the test distance.  Doesnt matter if you move the chart further away.  Likely the test chart wont show anything.  In order for the distance test to work you would need a chart that is proportionately larger to show the same pattern but larger scale.

For example moving the same chart out to twice the distance will double the number of lines shown per mm...so you are effectively trying to test the lens at an even finer resolution which most sensors would likely not be able to resolve.

This is a very good point, and not one I've seen covered in any depth on most review sites I've come across- anybody know any review sites where this is considered with more than a passing comment?

I have not seen any. Maybe the reason is that every such site has one (expensive) chart only and this pretty much determines the distance. I believe that you can still test at different distances even with the same chart, in the center at least; but they do not do that.

287
What we dont know is how many 70-300s were sent in for warranty that were screwed up from someone trying what they shouldnt.  If it's not supported why should they bother writing firmware and lens profiles to support the combo?

Anyway, likely that it wont ever be supported until they make a design change to the 70-300....or the 1.4x.  :)

You can roll back to the old firmware but you better download it now as it wont be an option to DL after the 30th.

Yeah but they could simply leave it off the supported list but have it still work anyway. It's not like someone couldn't give a try now anyway, people are anyway, so what is the difference. They could make it work but also say it is not supported.

Really stinks.


I dont think that was ever in the cards.  The risk to Canon is too high to have people zoom back to 70 with the xtender on and damage the lens. 

I wonder if the 2XIII now works with the 100-400 zoom?

Argggghh! I hope the 1.2.1 leak is not the final release.

It doesn't seem to recognize using the 1.4x TC III with the 70-300L! (and it fits perfectly at the long end)

It doesn't seem to recognize the TC is on :(.

It doesn't report it as a lens + TC combo for micro-adjustment and it says f/5.6 instead of f/8 :(.

The AF is awful! It does a hyper oscillation before settling in (only 1/3 of the time is it actually in focus :( ) and it's so slow.

It seems like they decided the 1.4x TC III is not compatible with the 70-300L so they don't let it work with the new f/8 AF mode :(. Even though it fits perfectly fine if you keep it at the long end.

Even if they don't official claim support for the combo for fear of someone crying that they tried to go to 70mm and it hit it would be nice if they would just let it work even without being on the official list!

It was precisely with this lens that I cared about f/8!! I have my 300 2.8 that works fine with either 1.4x or 2x III TC already but that is so heavy so it would'be been nice to get f/8 out of the 70-300L for the times I don't wanna lug the beast around which can be a real pain.

Ironically, now I guess I need to spend another $250 and get a kenko? Maybe I should dump the canon 1.4x TC to pay for it.

But people say the Kenko is not as sharp with the 70-300L (or other lenses) and that they notice a bit of a quality difference with the 70-300L. What a shame.

I hope the final release version firmware is different or they allow for a patch. :(

It's quite a tremendous shame since the 70-300L actually maintains pretty solid quality with the Canon 1.4x TC III.  At f/6.3 (f/9) the quality is relatively solid and it is definitely better than upscaling the bare lens, absolutely. It would be soooo useful! COme on Canon THIS is exactly the kinda scenario we wanted f/8 AF for! But seemingly being locked out of the new f/8 mode the 70-300L + 1.4x TC III AF is such an utter colossal wreck :(. But the optical output is solid enough to be usable so it's frustrating.

288
I dont think that was ever in the cards.  The risk to Canon is too high to have people zoom back to 70 with the xtender on and damage the lens. 

I wonder if the 2XIII now works with the 100-400 zoom?

Argggghh! I hope the 1.2.1 leak is not the final release.

It doesn't seem to recognize using the 1.4x TC III with the 70-300L! (and it fits perfectly at the long end)

It doesn't seem to recognize the TC is on :(.

It doesn't report it as a lens + TC combo for micro-adjustment and it says f/5.6 instead of f/8 :(.

The AF is awful! It does a hyper oscillation before settling in (only 1/3 of the time is it actually in focus :( ) and it's so slow.

It seems like they decided the 1.4x TC III is not compatible with the 70-300L so they don't let it work with the new f/8 AF mode :(. Even though it fits perfectly fine if you keep it at the long end.

Even if they don't official claim support for the combo for fear of someone crying that they tried to go to 70mm and it hit it would be nice if they would just let it work even without being on the official list!

It was precisely with this lens that I cared about f/8!! I have my 300 2.8 that works fine with either 1.4x or 2x III TC already but that is so heavy so it would'be been nice to get f/8 out of the 70-300L for the times I don't wanna lug the beast around which can be a real pain.

Ironically, now I guess I need to spend another $250 and get a kenko? Maybe I should dump the canon 1.4x TC to pay for it.

But people say the Kenko is not as sharp with the 70-300L (or other lenses) and that they notice a bit of a quality difference with the 70-300L. What a shame.

I hope the final release version firmware is different or they allow for a patch. :(

It's quite a tremendous shame since the 70-300L actually maintains pretty solid quality with the Canon 1.4x TC III.  At f/6.3 (f/9) the quality is relatively solid and it is definitely better than upscaling the bare lens, absolutely. It would be soooo useful! COme on Canon THIS is exactly the kinda scenario we wanted f/8 AF for! But seemingly being locked out of the new f/8 mode the 70-300L + 1.4x TC III AF is such an utter colossal wreck :(. But the optical output is solid enough to be usable so it's frustrating.

289
Lenses / Re: EF 300mm f/2.8 ( non IS ) AF ISSUES
« on: April 28, 2013, 08:59:16 AM »
Ouch.  I thought all of the 300's offered full manual focus.  Guess I'm wrong on that.  Then it's either a repair or sold for parts.  Quite a shame too because the optics are great.

And a lens of this quality STILL has value as a MF lens.  Not ideal but at least would help maybe pay for some of a new or used IS model.



No it doesn't. It is a fly (focus) by wire lens, if the focus motor is faulty then it won't manual focus either, this is a huge problem for all focus by wire lenses and makes early supertele ownership an ever riskier proposition.

290
Lenses / Re: 400mm L f/5.6 vs 100-400mm L IS f/5.6
« on: April 28, 2013, 07:22:16 AM »
I would get the 400l. I tried two copies of the 100-400 and its soft wide open or rather yields halos around bright objects.  It also interferes with AF which I found slow to start with and hunted around a lot.  I missed a lot of bird in flight shots.  I returned it for a 70-200 2.8l IS II with a 2xiii extender.

The 400 5.6l is pretty sharp wide open.  AF is quick and it locks reasonably well with BIF provided you have enough light or high enough ISO.

291
Lenses / Re: EF 300mm f/2.8 ( non IS ) AF ISSUES
« on: April 28, 2013, 06:56:02 AM »
And a lens of this quality STILL has value as a MF lens.  Not ideal but at least would help maybe pay for some of a new or used IS model.

I think the OP is in Brazil (since he mentions São Paulo), so a US 3rd-party repair center may not help him that much.
Since Canon has stopped servicing them, they might be willing to point to a 3rd party in Brazil that could help.

Mt Spokane: I think the part you linked appears to for the IS MkI version. A focus unit for the non-IS seems to be like $1250:
http://www.ebay.com/itm/NEW-CANON-EF-300mm-1-2-8-L-USM-FOCUSING-UNIT-AL-625-/390183359378?pt=Digital_Camera_Accessories&hash=item5ad8bd9392

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You are right, I missed that even though I was looking for it.  In any event, new and used parts can be had, but at some point, a lens becomes more valuable for parts.

292
Lenses / Re: Lens sharpness and distance from subject
« on: April 27, 2013, 10:31:10 PM »
No actually the original question was about distance affecting sharpness of a lens...and the answer is quite clear.  Distance does not affect sharpness.  The amount of light affects sharpness.  Quality of optics and alignment affects resolution of a lens.  What the camera can resolve is up to the sensor.  The lens resolution should be relatively fixed..but that is not always the case because no one can make a perfect lens.

Actually it IS all about the differences.  You can sharpen an image in Photoshop but you cannot increase the resolution of the image.  They are two different things measured in complete different ways.

All of this is unrelated to the OP - the question was clear enough.

We are not talking what you can create in PS - we are talking about the IQ of the lens and the sensor. And no, they are not measured in completely different ways - all that is measured is the MTF curve, usually by the slanted edge method (which actually computes the MTF using the Fourier transform). The rest is words.

293
Lenses / Re: Lens sharpness and distance from subject
« on: April 27, 2013, 10:23:33 PM »
With zooms yes you can get difference it resolving ability.  You can also see the difference in resolution if you are not obtaining precise focus.  Some lenses focus better closer than at infinity.  It's not supposed to be like that and usually indicates a bad design, a defect, or simply needs to be calibrated at the factory.

Resolution is measured in lines/mm at a certain distance.  If you extend the same chart further out you will resolve less lines and that's because the resolution of the lens is fixed whereby you are changing other constants in the measurement.  Maybe a better way to explain it is lines/mm can also be measured as an angle...a very small angle... if you move your subject further away, that angle becomes smaller.  The lines/mm resolution of the lens does not change, it's that the subject now fits in fewer lines because the angle is smaller...All of that in a world where lenses are perfectly machined and assembled.

That being said, most of these lenses are quite complex with lots of moving parts, lenses move closer and further away during AF and zoom functions.  It is possible that due to lack of tolerances in the machined parts that move that one or more lenses my not be in the same alignment from one focus point to another.  most people wouldn't notice it but if you are pixel peeping then you might notice some differences...and it could get worse as the lens is used and wears out.

So it is not "sharpness" but resolving ability. So let me rephrase my question - is there any source to learn about canon (many or most) lens's variable "resolving ability" with distance from the subject. And I am talking about different distances like 2-5 meters, 5-10 meters, 10-20 meters etc. (or there counterparts in feet).

To put it in a slightly different language what I am trying to know is if it is true that every prime lens is optimized (in terms of resolving power) for a particular (or small range) of distance from the subject (not sure how to put it in terms of zoom lenses) and if so is there any source (that you know of) to know which canon lens is optimized for which distance (or range of distance) from the subject?

Thanks for the reference to "atmospheric distortion", I just looked it up. No, I am not talking about that.

294
Lenses / Re: Lens sharpness and distance from subject
« on: April 27, 2013, 10:12:24 PM »
Actually it IS all about the differences.  You can sharpen an image in Photoshop but you cannot increase the resolution of the image.  They are two different things measured in complete different ways.

Maybe you are referring to resolving ability.  That is not sharpness.  Sharpness is created by having a stronger light and dark along lines in an image.  More light means more sharpness.  Less light gives it more softness.

There is no much difference. Sharpness is a loose term for MTF-50 or so. Resolution is another loose term for lower MTF, like MTF-10 to 20.

295
Lenses / Re: Lens sharpness and distance from subject
« on: April 27, 2013, 06:58:01 PM »
???

Maybe you are referring to resolving ability.  That is not sharpness.  Sharpness is created by having a stronger light and dark along lines in an image.  More light means more sharpness.  Less light gives it more softness.

It does. Use a lens at 1m, then at infinity - it is a different lens really. I have noticed this with my 17-55 - much better at 2-3m than at infinity.

Many people test lenses at close distances and make far reaching conclusions; and this is wrong.

296
Lenses / Re: Lens sharpness and distance from subject
« on: April 27, 2013, 05:09:24 PM »
Distance has nothing to do with sharpness.  It's all about having more light to increase the contrast between light and dark edges.

297
Lenses / Re: EF 300mm f/2.8 ( non IS ) AF ISSUES
« on: April 27, 2013, 05:07:09 PM »
No you don't want to use a pencil eraser.  The eraser can leave a residue behind as we'll as get debris possible in the lens.  They are also too abrasive for gold contacts, possible wearing the gold surface down even more.


A fine lens it is.  Check the gold contacts on the back.  Sometimes cleaning GENTLY with a qtip and alcohol will help.  Other than that you should call Canon and see if they will check it out for you.  It's worth it to get it fixed even though 14yo.  I bet it's the contacts though.  They don't last forever.

I've also see this happen with dirty battery contacts since on some cameras the AF motor gets its power directly from the battery.  However since you have tried it on several bodies, I would say it's likely the contacts.  But it could be something internal that needs to be repaired.

+1    A pencil eraser also works...

298
Lenses / Re: EF 300mm f/2.8 ( non IS ) AF ISSUES
« on: April 27, 2013, 04:21:35 PM »
A fine lens it is.  Check the gold contacts on the back.  Sometimes cleaning GENTLY with a qtip and alcohol will help.  Other than that you should call Canon and see if they will check it out for you.  It's worth it to get it fixed even though 14yo.  I bet it's the contacts though.  They don't last forever.

I've also see this happen with dirty battery contacts since on some cameras the AF motor gets its power directly from the battery.  However since you have tried it on several bodies, I would say it's likely the contacts.  But it could be something internal that needs to be repaired.

299
EOS Bodies / Re: Download Firmware 1.2.1 link for 5DIII
« on: April 26, 2013, 10:50:00 PM »
How stable is ML on the 5d3?  I used to use it on a t2i for intervalometer function but it frequently crashed and so finally just gave up.

now they need to implement lots of the cool features ML has like the new RAW histogram

Appreciate it

oh well i will just keep using ML nothing in the new FM is useful for me, now ML can shoot 2040x1428 14bit RAW DNG without shutter actuation on 5D3 very good for time lapse. While Nikon can do time lapses canons cant without a intervalometer probably so that they make more money.

300
5D MK III Sample Images / Re: 5D MK III Images
« on: April 26, 2013, 04:46:22 PM »
600mm F4L IS - ISO 2000


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