December 19, 2014, 02:21:47 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 - Meh

Pages: 1 ... 37 38 [39] 40 41 ... 47
EOS Bodies / Re: 5Diii vs 7Dii (FF vs APS-C)
« on: November 02, 2011, 04:09:15 PM »
But in a real-world application, DoF is shallower with FF (because you have to move further from the subject to compensate for the narrower angle of view with a crop sensor).

I like the way you phrased "real-world application"...  unless something is preventing the photographer from moving, he/she will move forward or back to compose the shot and to get the desired framing one would naturally (without thinking about the technical aspects) move a little further away with a crop sensor camera according to what is seen in the viewfinder.  And because we don't walk around with DoF calculators we might tend to choose the same aperture setting and when we look at the images we do in fact observe that the FF gave more background blur.

EOS Bodies / Re: 5Diii vs 7Dii (FF vs APS-C)
« on: November 02, 2011, 03:16:16 PM »
@Meh - Exactly, it's the iris diaphragm that matters. Practically, since you have to actually do simple math (eek!) to determine that from the focal length and f/number, it's more practical to use those values to determine DoF.

LL's experiment with the gremlin is approximately correct. In fact, at the distances involved it's actually not the best approximation. I don't agree that the degree of unsharpness is identical - but it's close, good enough for approximation. I've tried an equivalent experiment, as a post hoc test, with my AFMA testing. Since I use 25x the focal length for all lenses, and the LensAlign fills the same proportion of the frame (i.e. distance and focal length are equal and opposite).  With an actual distance scale on the ruler, it's apparent that f/2.8 at 16mm (16-35/2.8L II) and at 200mm f/2.8 (70-200mm f/2.8L IS II), the measured DoF is the same, when distance and focal length are reciprocal.

Actually, the reduction of DoF to dependence only on magnification holds at macro distances (and for microscopy, although we usually call it axial resolution not DoF, and use numerical apertures vs. f/numbers).

Neuro: Please dumb this down for me... (you have done this many times  :) ) : Bokeh notwithstanding.... do i get more or less OOF blur (Quantity) is APC-S or with FF. Give me some numbers in feet etc if you can... cause "framing and similar terms are relative  :-\

I'm no neuro but I can take a shot to rephrase it into less technical terms....  we'll see if I have this right!

If you use the same lens, set to the same aperture, and place the camera the same distance from the subject, you will get more OOF blur with an APS-C sensor compared to a FF sensor.

If you use the same lens, set to the same aperture, and place the APS-C camera 1.6X further away from the subject than the FF camera (to get the same framing) you will get more OOF blur with the FF camera.

If you use the same lens, set to the same aperture, and place the APS-C camera 1.26X further away from the subject than the FF camera you will get the same OOF blur. (1.26 is the square root of the ratio of CoC of FF and APS-C)

If you use different lenses (two different focal lengths) on the same camera but set to the same aperture, and place the camera at the same distance from the subject, the shorter focal length will give less OOF blur.

If you use different lenses (two different focal lengths) on the same camera but set to the same aperture, and place each camera at 25X (or any multiple) of the focal length, both lenses will give the same OOF blur.  (This is the gremlin example on LL that keeps the subject the same size)

Canada / Re: Futureshop VIP sale Thursday, Aug 11th.
« on: November 02, 2011, 11:38:59 AM »
Best Buy now owns Future Shop. Curiously, they now often build stores side by side with BB targeting Joe Consumer and FS targeting the technophiles. I've spent a small fortune at FS since the late '80s and have never seen bait and switch. If they advertise a product that may not be in stock they always tag the ad with "limited quantites per store". But the only time this seems to be used is Boxing Day.

Agreed.  I've never had a problem with FutureShop.  Even the much maligned extended warranty program treated me well a number of years ago on a laptop that died.  It took a little over a week but they got working (claimed to have replaced components but who knows and it's still working and running XP fine despite being 7 years old (I use it as a backup/test machine).  I don't buy the extended warranty on laptops anymore... they're more reliable than they used to be and the replacement cost is low enough to just buy a new one in the unlikely event something goes wrong.

EOS Bodies / Re: Does a Digital camera need SLR?
« on: November 02, 2011, 10:51:54 AM »
Review of Fujifilm's image sensor phase-detect AF is explained on dpreview so it can be done.

They claim AF speed of 0.158 seconds but obviously DSLR AF is much faster since shooting at 10 frames per second and autofocusing in between frames must be less than 0.1 s.   So at least in those fuji compacts, that system is not as fast.
Im afraind you may confuse DSLR with AF. they may be quit different concept.
To be frank, 0.16s is rather quick for a mechanism. but DSLR is a optical route reflected by prism. which can can get a accurate image positoin on the film through finder.

or say, ccd or cmos sensetivity is faster than mechanism  movement which drive lens to a fit position. one is electronic, another is mechanism.

however, lens has a large mass.

I'm not confusing the two, but I can see why the way I wrote my comment may be unclear...   The Fuji is a mirrorless camera and is therefore not a DSLR.  So, my comment was comparing the 'phase-detect AF built into the image sensor of the Fuji' to the 'phase detect AF implemented in separate AF sensor of a DSLR'

Unfortunately, I'm not sure what your other comments are getting at but perhaps you also misunderstood why I referred to the fps of a DSLR.   I did that to demonstrate that the phase-detect AF in a DSLR using a separate sensor is much faster than the Fuji system... if a DSLR can shoot at 10fps then the AF must be able to focus in less than 0.1 s because it is happening in between each flip of the mirror.

Hopefully that's clearer than my shorter original comment.

EOS Bodies / Re: 5Diii vs 7Dii (FF vs APS-C)
« on: November 01, 2011, 07:50:50 PM »
Basically, aperture determines DoF.

Correct as usual but I'll add, just in case a few people don't know, it is the actual physical size (the diameter) of the aperture that affects DoF not the f-number (although the f-ratio typically falls out of optical formulae when you end up with an f/d).  If it wasn't for diffraction, a tiny aperture would render everything in focus with no need for a lens which is how a pinhole camera works.   Yes, in the DoF calculators you must plug in the f-ratio but that is just used (along with focal length) to calculate the diameter (in mm) of the aperture.  My turn to wait for a correction from neuro :)

Question to neuro (because I just tried but quickly gave up playing with the formulas):  changes in subject distance and focal have an opposite effect on DoF but is it equally offsetting for the same framing/subject size?  There is an article on Luminous Landscape that demonstrates that if camera position changed to keep subject size the same within the frame, DoF remained visually equal regardless of focal length.  This makes sense when one understands that the physical size of the aperture is smaller for shorter focal length lenses for the same f-number.  But is it mathematically equal at least first order?

EOS Bodies / Re: 5DM2 Purchase From Canada (Henrys) to USA
« on: November 01, 2011, 04:22:46 PM »
Hi all.

I'm a US citizen and noticed Henry's Camera has 5dM2 for a great price. I sent them an email and received this response: (they were NOT in stock at the time)

"Payment for items being shipped to the United States is by PayPal only.  The charge of $2012.95 is in Canadian Funds and will be exchanged into US funds at time of shipment.  We will not set US Funds exchange until then as the exchange rate varies on a daily basis."

Theoretically, if the camera was shipped today, the exchange rate would be: (2012.95 would convert to $1973.87 US Dollars)

I then sent them an email and requested if any other fees would be charges as I'm just trying to find out EXACTLY how much I will be charged.

They responded: "We have the camera in stock as of the writing of this email.  If you ordered today it should theoretically ship tomorrow.
There may be brokerage fees associated with your purchase, but they are set by the USPS."

I do not know what "Brokerage fees" are and sent an email requesting explanation but have not heard back. I then did some research via Google on the term "brokerage fee"  and found this:
NOTE on Brokerage Fees (there are none): Because USPS & CanadaPost have long standing agreements to handle each other's mail, brokers' fees are NEVER charged. EXPENSIVE BROKERS FEES MUST be CHARGED BY MOST OTHER COURIER/SHIPPING SERVICES. BUT NOT USPS or CANADA POST! :-)"

Could anyone tell me if Henry's is a reliable source and what the final charge would be for a 5dm2 purchase? Also, don't understand brokerage fees and i'm a bit skeptical at this point.

Thank you.

Henry's is very reliable, they are a major retailer in Canada.

Brokerage Fees are the fee the shipper will charge you to process the importation of the product.  USPS may not charge you anything.  UPS definitely will charge you brokerage fees for ground shipping but usually not for air shipping.  Note that my experience is based on shipping from the US to Canada.

EOS Bodies / Re: EOS-1D X Canon USA Press Release
« on: November 01, 2011, 04:03:47 PM »
Plotting the prices of current cameras from the T3/1100D through the 5DII, the best curve fit is a 2nd order polynomial (R2 = 0.99344)...

Neuro is the best.  Love it.  +1

EOS Bodies / Re: Big 5D Mark II Price Drops in Canada & USA
« on: November 01, 2011, 10:54:17 AM »
So, it is Nov 1st and the 5D2 is still $2000 here in Canada and the 5D2/24-105 kit is $2800. When are the rebates supposed to end?

Most of the Canadian retailers are still offering the 5D2 body for $1999 but don't have stock.  The Vistek website indicates they have stock but they increased their price a little over a week ago maybe because the stock at other stores was getting low (just guessing).  FutureShop website states the $1999 sale price is in effect until Dec31st and maybe it was FutureShop that led with that sale price... all the other retailers offer competitive price matching.  Futureshop is also out of stock now but I would expect them to have more on order if Canon even has stock.  I picked up the 5D2 body for $1899 last Friday when they had a one-day offer of $100 off any camera over $1000 in addition to any sale price.

EOS Bodies / Re: 5Diii vs 7Dii (FF vs APS-C)
« on: October 30, 2011, 10:15:15 PM »
No I wasn't - else I would have quoted your comment

Fair enough.  You'll forgive me for thinking so given that you commented immediately after me and I hadn't noticed anyone else had made a statement similar to what you put in quotations marks.

I wouldn't accept that the 7D is 'far superior for sports action photography' over the 5DII. It has the edge on AF and fps - but not that much - as it then loses out on iso. From experience it is in wildlife where the 7D pulls away more.

Interesting view and actually I appreciate that from someone who has used the 5D2 and 7D as extensively as you have.  I've used the 5D2 a few times (borrowed) but only just recently bought one since the prices are now so low and I'm glad to know it will be more useful for sports photography than I thought it would be.  I don't think the general consensus (going by what I've heard and read on this site and elsewhere) is that the 7D only has a small edge on the 5D2 for AF and fps.  It also has an edge over the 5D2 on weather sealing which is certainly beneficial for outdoor sports.

I feel that reading something into Flickr stats would apply only to Flickr users. Not that many serious or pro togs using Flickr - they have their own websites.

True, stats can be misleading if applied to populations that are not well represented by the sample population.  If there are few pro photographers posting to Flickr as you say then any insights can not be applied to pros.   Several of the comments about the Flickr data questioned the applicability and from a statistics perspective I think that there could be a bias in the "type of user".

I just copied the Flickr usage stats for Canon into Excel and added it up for fun (fun?) to see what it looks like for all camera types.  The "avg. daily users" is a one day snapshot so the numbers I have a different from what 7enderbender got and the "one day" thing is itself a limitation.  Data from yesterday is a total of 47,370 members posted a photo with a Canon camera.  Of those 34,218 (72%) were from a DSLR.   Of those 8,617 (25%) were from a 5D, 5D2, or 7D and 25,601 (75%) were from any other Canon DSLR.

I agree it's not something we can draw big conclusions from but it's interesting.

EOS Bodies / Re: 5Diii vs 7Dii (FF vs APS-C)
« on: October 30, 2011, 11:30:44 AM »
"progressed from a 7D to a 5DII" now that is a contentious statement.

This is a presumption that APS-C is the cheaper, less worthy camera and that only 'real' photographers graduate to full frame - ie sensor snobbery.

When will people realise that Full frame and Crop bodies are just tools for different jobs. One is not better than the other - just different.

If you're referring to my comment, then what I said was "picked up a 5D2 as they progressed in their photography" which did not imply that either camera was better than the other.  I agree they have different strengths and weaknesses... the 7D is far superior for sports action photography for example but the 5D2.  My point was only about the relative likelihood of the large group of 5D2 owners picking up a 7D as a second body vs. the opposite as a possible theory to explain the skew in the flickr stats and that theory was it's more likely that at this point in time, many more "enthusiasts" bought a 5D2 when it came out and did not add a 7D as a second body versus those that bought a 7D then also picked up a 5D2.

EOS Bodies / Re: 5Diii vs 7Dii (FF vs APS-C)
« on: October 29, 2011, 11:04:45 PM »
c) if you look at the camera usage stats on flickr for instance you'll see that there are over 10,000 average daily users who have one of the recent Rebels. Around 4,100 have a 5DII. 3,300 have a 7D and only 1700 used a 60D. 

You could argue that the 5DII has been around for longer...

Regarding the numbers for 5D2 and 7D, I'm inclined to think the fact the 5D2 was released a year earlier is quite significant.  At the time, the 5D2 was quickly grabbed up by huge numbers of "enthusiasts" most of whom wouldn't have bought a 7D as a second body.  In other words, many/most of the enthusiast market willing to buy at the higher price points already went with the 5D2.  So by the time the 7D came out the middle-market was partially saturated and a higher percentage of those that bought the 7D might have picked up a 5D2 as they progressed in their photography.   I'm just guessing but that seems logical to me (because I am one of the latter ;) ) and if so it would partially explain the stats.

EOS Bodies / Re: No 5D Mark III on Novemeber 3 [CR2]
« on: October 29, 2011, 12:04:38 AM »
The prices of the 5D2 are just too low that I couldn't hold out any longer.  Picked up a 5D2 body for $1899 today but won't open the box until after Nov 3rd.  Just in case bornshooter is right this time!!!  ;)

EOS Bodies / Re: 5Diii vs 7Dii (FF vs APS-C)
« on: October 29, 2011, 12:01:54 AM »
Makes sense, was just wondering if I was missing anything besides apparent mag. Personally, I'll take real mag, and if 1:1 isn't enough, I'll go to 5x with my MP-E 65mm...and if that's not enough, I'll just use a microscope.  :P

I don't have an MP-E 65mm and, just a second let me check, nope don't have a microscope either :)   1:1 is the same regardless of sensor size but not all subject are the size of a FF sensor and may be smaller than an APS-C sensor and in that case you get more pixels on subject with the 7D.

Lens Giveaway Contest / Re: *Contest* Wildlife - Post Here.
« on: October 27, 2011, 09:31:53 PM »
Red Fox caught in a trap.

Did you set him free after you got the shot?

EOS Bodies / Re: Does a Digital camera need SLR?
« on: October 27, 2011, 01:58:49 AM »
Review of Fujifilm's image sensor phase-detect AF is explained on dpreview so it can be done.

They claim AF speed of 0.158 seconds but obviously DSLR AF is much faster since shooting at 10 frames per second and autofocusing in between frames must be less than 0.1 s.   So at least in those fuji compacts, that system is not as fast.

Pages: 1 ... 37 38 [39] 40 41 ... 47