April 23, 2014, 05:44:39 AM

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - WillThompson

Pages: 1 [2] 3 4
16
A EOS lens is only functioning to specification when powered up with a body.

The aperture setting is not a passive but an active device!

Is that metered manual or auto exposure?

In auto the camera can skew both settings by 1/6 or is that multiple 1/10's of stops with no indication of f-stop or shutter speed change. (Not sure of the sub step values that Canon uses 1/10 vs 1/6, It has been a long time since I went to Canon school)

So answer me this, how many stops difference is f1.2599 from f1.4142??????

17
Lenses / Still only 1/3 stop difference! (When using 1.3 stop steps)
« on: July 14, 2013, 02:07:52 PM »
That difference is best represented as 1/2-stop, whether or not the settings of the camera result in that complete 1/2-stop being used.

Still not correct.


With a 1/2 stop setting f1.2 is actually f1.1892.

With a 1/3 stop setting f1.2 is actually f1.2599.

With both a 1/2 & 1/3 stop setting f1.4 is actually f1.4142.


This difference is why the 1/2 stop setting between f1.4 & f2.0 is f1.7 not f1.6 or f1.8 as it is less confusing due to larger numbers allowing better numeric distinction between settings.

On a side note,

Is a f1.2 lens actually 1/6 stop wider when set to 1/2 stop increments when shot wide open???

18
Hmm...right, it's a 1/2 stop, sorry.


No it is 1/3 stop!

The 1/3 stop steps are: 1.0 1.1 1.2 1.4 1.6 1.8 2.0 .........

No, it's both, or if you prefer, neither.  On the half-stop scale, f/1.2 is 1/2-stop wider than f/1.4, but on the 1/3 stop scale, f/1.2 is 1/3-stop wider than f/1.4.  See the wikipedia page on f/stops

Mathematically, f/1.2 really is closest to a 1/2-stop, since 21/2x0.5 = 1.1892), whereas 22/3x0.5 = 1.2599, which personally I'd round to f/1.3.


Not on a canon camera that actually uses 1/6 stop increments, when setting exposure.  The camera uses the standard 1/2 stop nomenclature but uses actuall 1/2 stop increments when set to 1/2 stop steps and the same goes for 1/3 stop steps so the steps will be exactly 1/3 or 1/2 depending on the camera setting.

This means that the difference between a setting of 1.2 and 1.4 will be different depending on camera settings.

In the real world there is 1/3 stop difference as apposed to the representational of 1/2 stop steps!

19
Hmm...right, it's a 1/2 stop, sorry.

No it is 1/3 stop!

The 1/3 stop steps are: 1.0 1.1 1.2 1.4 1.6 1.8 2.0 .........

20
For me the price of $175 and simplicity the Manfrotto 393 Heavy Duty Telephoto Lens Support beats all the others!

It comes with the quick disconnect and long mounting plate shown in the photo.

They show it on a monopod in this photo and have the lens overhead,  I have mine on a large Canon heavy duty tripod with my 300 2.8 IS lens on the bottom.  With mine on the bottom it returns to level when released with a light pivot tension setting.

I think top or bottom depends on lens balance needed.



Reminds me of the telescopes at the pier.

21
EOS Bodies / Re: Canon 1DX Damaged by CPS
« on: July 12, 2013, 12:06:32 AM »
Any advice on how to deal with CPS when I call them tomorrow morning (they are currently closed) would be greatly appreciated.

CPS support is open 24/7

Use the support not the repair option, and ask them what to do next.

Will T.

22
Pricewatch Deals / Re: 600EX-RT speedlite deals?
« on: July 03, 2013, 10:17:53 PM »
, they'll cost maybe $50 less than brand new from another dealer who will also bundle them with extras and offer other incentives and what not. 

More like $21 less than B&H since they have free shipping.

I was quoted $489 total shipped from the Canon USA website for a refurb one today so I passed.

Will T.

23
EOS Bodies - For Stills / Re: 35mm film body
« on: June 30, 2013, 09:27:11 PM »
Try KEH.COM

They have tons and give a 6 month warranty on used.

P.S. has any one noticed that Canon USA now has a 1 year warranty on refurbished gear?

24
Lenses / Re: Lens Resolution fact or fiction?
« on: June 29, 2013, 11:34:37 PM »

So if that is the case, then the DXO resolution measurement is a total BS
What do you think?

I totally agree that DXO is mostly BS but not for the reasons you mention!

25
Use an ext tube.

26
Lenses / Re: Would you sell yours ? or did you ?
« on: June 29, 2013, 08:23:21 PM »
Do you use the 100mm as a macro or just a 100mm with IS. 

THE 70-200mm f2.8 L IS USM II is just as sharp at 100mm as the macro is so if you do not need macro get rid of it!

27
This thread title made me very angry - it's Canon fanboys like OP that drive the insane Canon glass prices up. 3rd party lenses can be just as good as Canon's at fraction of the cost. Don't blindly recommend Canon's glass against Sigma, Tamron, Tokina, Samyang etc. - they all have some outstanding products, while having to reverse-engineer the AF communication.

/rant

Can be but are not up to canons quality.  The only contender is Tamron due to the fact that they are only mfg. that canon has contracted with.  This is why you never hear of a Tamron lens needing to be rechipped, still junk compaired to canon build quality just like all the other third party mfg.'s.

Will T.

28
It is not a 1DX! :'(

29
High precision AF starts at f2.8, so use 2.8 or faster.

If AF speed is important use f2.8 for the best of both, if not go as wide as you can.

30
EOS Bodies - For Stills / Re: F/8 Autofocusing impressions
« on: May 17, 2013, 01:38:45 AM »
I've used my 1D X with a 600/4 II and 2xIII to track birds in flight, sometimes handheld. It does fine.  However, when shooting small birds in thickets (branches in front of and behind subject), where the bare 600 II locks onto the bird easily, with the 2x it hunts a bit - in that situation, it behaves a lot like the bare 100-400L.

Did you use spot single point or regular single point focus for this test?

Thanks, Will T.

Pages: 1 [2] 3 4