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Messages - Rocky

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481
Lenses / Re: Why not EF-s "L" lenses?
« on: August 08, 2011, 02:21:26 PM »
Therefore the EF-S 35mm can be made better than a 35mm EF.

Can be.  But will it be? Canon may very likely sacrifice IQ to keep cost low (Nikon's 35mm f/1.8 DX is $200).  The current 35mm f/2 on APS-C is optically better than the 18-55mm f/3.5-5.6 IS kit lens, and actually delivers IQ similar to the excellent 85mm f/1.8.  How much optical improvement do you expect from there? 

The main complaints about the 35mm f/2 are that the build quality is poor, no USM, etc., and if they release an EF-S version of the lens, I doubt the build quality will be all that much better (assuming their target market is similar to Nikon's for that lens, they'll price it accordingly, and it will end up with build quality closer to the 18-55mm kit lens than to the 60mm macro).
You are right again.
May be Canon marketing have an idea that people like to think " Mine is bigger than yours". So APS-C  user are  forced EF prime lenses. For the deep pockets they go for BIG prime L lenses. For none deep pocket, they use non-L prime lenses.
Unfortunately, I am from a slightly old school . I like it small and  good.  That is why I am longing for good EF-S prime. As for the pricing, If the 7D user will spend $1600 on the body only, I am sure that they would not mind to pay for a EF-S good prime (optically and true USM) with the price close to the L lenses with smaller size and weight.
I know, I am the minority.

482
Lenses / Re: Why not EF-s "L" lenses?
« on: August 08, 2011, 01:13:17 PM »
It would certainly be possible for an EF-S 35mm lens to outperform an EF 35mm lens, but that would not be because designing a 35mm lens to cover an APS-C image circle is equivalent to designing a 56mm lens for FF.  Focal length is the distance from the rear nodal point to the image plane, regardless of the sensor size.  So, a 35mm lens for APS-C still must be designed with a 35mm focal length.  The mirror on an APS-C camera is only ~9mm shorter (vertical dimension) than that on a FF camera, so an EF-S 35mm lens can would still require the retrofocus design you need for wide angle lens.

The real benefit to the EF-S format is that the image circle is smaller, which means the elements of the lens can be smaller in diameter.  In the case of the inexpensive kit lenses, that usually just means less glass can be used, so the lens can be made more cheaply.  But, it also means the for the same cost and lower total weight, they can include more elements in the lens design, or better-made elements (e.g. molded glass instead of a resin replica for aspherical elements), or both, and that increases the ability of the lens to correct for aberrations - i.e. better IQ.
You are right. the reduction of 9mm between the back element of the EF-S lens and less than half of the covered area will definitely give the 35mm EF-S  an edge to giveuis a better lens. It still needs retrofocus design as you mentioned. But the design should be a lot esier. Therefore the EF-S 35mm can be made better than a 35mm EF.

483
Lenses / Re: Why not EF-s "L" lenses?
« on: August 08, 2011, 04:04:48 AM »
I wouldn't expect a EF-S version to get worse, but unlike the Nikkor side, I also don't expect it to get that much markedly better, either.
If it is done right, the 35mm EF-S can outperform a 35mm EF easily. The 35mm EF is a wide angle lens (to cover the FF sensor). While 35mm EF-S (with equilvalent focal length of 56mm) is slightly longer than a "normal lens". Anybody with knowledge in lenses knows that it is harder to design a good wide angle lens than a good normal lens for SLR or DSLR due to the flange focal distance (42 to 47 mm depends on the camera, for Canon is 44mm). If fact most the SLR had 55mm as "normal les until the mid 60's for the same reason. They just cannot make a good 50mm lens. Also 35mm EF-S just need to cover less than half of area of FF. If they cannot make the35mm EF-S better than the 35mm EF, something is really wrong.
That is the reason we are asking for some short EF-S prime lens. may be a 30mm  f1.8 and a 17mm f 2.8 prime in EF-S mount.

484
EOS Bodies / Re: Micro Focus Adjustment on 60D
« on: August 06, 2011, 02:42:21 AM »
It is a shame that canon do not put MFA in the 60D. It is a no cost extra for Canon. We, the comsumer will benefit a lot when we need it.  Canon should not expect the 60D user to use slow lenses and not  being critical all the time. There is one arguement that I have read over and over again " Canon wants to distinguish 60D from 7D by not having MFA in 60D" This is a lame reason. There are a lot of feature that 7D has but not on 60D. There is enough distinction between them without taking account of MFA. The only real reason is Canon is forcing people to buy 7D for the MFA.  And we all know that 7D has a much higher profit margin than the 60D.

485
Lenses / Re: Why not EF-s "L" lenses?
« on: August 05, 2011, 12:36:26 PM »
I do think it would be a great idea for Canon to release a "Premium" line of EF-S lenses.
A blue ring would look nice  ;D

They could have three zooms (wide angle, general purpose and telephoto) and maybe three fast primes (f1.4) with focal leghts more adapted for the 1.6 crop factor.

Canon already has 17-50mm and 10-20mm. both are 'premium priced" EF-S. As for telephoto, It is really a waste of resouce to do EF-S. There are hardly any size (weight ) and cost saving. We may just use EF lens instead.
However. I am all for standard and wideangle EF-S lense. These are where the better performance and smaller  size will come in. I would like to see a 30mm f1.8, 17mm f2.8 to start with.  I did not ask for fast lens due to smaller size and better performance can be obtained with a "not that fast lens".

486
Lenses / Re: Why not EF-s "L" lenses?
« on: July 26, 2011, 08:49:27 PM »
We need some short focal length prime lenses for APS-C body. I do not care whether they are L lenses or not. As it is now, we are forced to use the EF prime lenses. That is a waste of weight, design and size of the lenses. I would like to see the following:
30mm, f1.8 or 1.4. This will make a good and smaller Normal lens.
21mm, f2.8 or f2.0. This  will be a 34mm equilvalent lens.
17mm, f2.8 , this will be a 27mm equilvalent lens.
13mm, f 2.8, this will be a 21mm equilvalent lens.
I did not propose any really fast lens in consideration of size, cost and design.
Hope Canon is listening.

487
EOS Bodies / Re: CF to SD/MMC reader on CANON Camera 7D
« on: July 26, 2011, 04:36:09 PM »
Hi guys, did anyone tried this on their CANON camera especially 7D.  I was just wandering if you can use this:

http://www.amazon.com/SD-CF-II-Type-Adapter-Supports/dp/B000YZGCIU
For that price, you can buy a 8G CF crad.

488
Lenses / Re: why????
« on: July 25, 2011, 05:17:01 PM »
Actually the $1000 FF DSLR can be built even Now. However, ALL DSLR company wants to keep the higher profit in the existing FF model and will not build a "Cheap"FF. just look at the following numbers: The cheapest Rebel is about $500 now. My previous tread calculated the difference of FF and APS-C sensor  can be $500 (based on the white paper from Canon dated 2006, now the gap may be even smaller). So $500 (Cheap body)+$500(upgrade to FF from APS-C) that is $1000. Let us be generous, add $200 to additional feature and bigger body. That is a CHEAP $1200 FF right there.

489
Lenses / Re: why????
« on: July 24, 2011, 06:45:53 PM »
why does no one make say a 16-50mm f2.0 or something similar for crop cameras sure it would be expensive but i think people would be willing to pay for it, i would pay 70-200mm is f2.8 is money for it.

On a side not canon should make an L-s range for good crop for lenses like this. i aim fairly certain within a few years full frame will be less popular with the ridiculous iso performance of  new crop cameras and the possibility of photo binning (don't ask me about it i'm a noob but basically you have option to reduce megapixels to get better iso performance)
The lens that you want  is an excellent walk around lens. However, it may be a monster in size and weight. just look at the 17-50 f2.8 EF-S. It is 4.4 inches long, using 77 mm filter and weights 1.4 lbs. If it was f2.0 and 16- 50 mm, it might be using 90mm filter or larger and weighed over 2 lbs easily.  The 16-35 already uses 83 mm filter. How many people will like to have a monster like tah tas a walk around lens and can be spotted from far away???

Since he is rerferring to APS-C, I assume he means EF-s, which would be about the size and weight of a 16-35, but it would likely cost more.
17-50 EF-S and 16-35 EF is already the same length and weight. I was using the 17-50 EF-S fiter size of 77mm
as starting point and use  the 18-55 EF-S (F3.5) 58mm filter size and the 16-35mm Filter size (77 mm) to guestimate the filter size. If between f3.5 and f2.8 (both EF_S) with increase of 19mm in filter size, I  guest an increase of only 13 mm between f2.8 and f2.0 is very stingy.  I have not yet taking the increase in viewing angle between 16mm and 17mm into  account. With increase in the size of optical elements, the weight will increase also. It fact I may have already under estimate the size  and weight of the 16- 50mm APS-C f2.0 lens.

490
Lenses / Re: why????
« on: July 24, 2011, 06:25:35 PM »
Canon uses 300mm wafers

I am glad that someone confirms that Canon is using 300MM wafer. I have been suspecting it for a while but I have no way to find out. If Canon is really using the 300mm wafer, then the price gap between APS-C and FF sensor will even be smaller due to: 1. the cost per unit area of finished wafer is smaller. 2. The ratio of site between FF and APS-C is closer due to the ratio between perifferal partial site to whole site is smaller. May be the difference in final cost can be down to around $200.

491
Lenses / Re: why????
« on: July 24, 2011, 04:21:58 PM »

and that would mean $30 per APS-C sensor (166 working chips out of a $5000 wafer), which sounds pretty reasonable, and tells me this format is not going away anytime soon
You must have been using the number from the white paper by Canon. the APS-C potential site is REALLY wrong. My estimate is that there may be only 75 sites for the 8 inch wafer for APS-C sensor. Let us assume the yield for APS-C is 75 %, then we will have 56 sensor per wafer, $5000 per wafer, that will be $90 per sensor. Assuming the yield for FF is 25% (1/3 of the yield  of APS-C, being pressimistic ). then each wafer will yield 5 FF sensor. that will be $1000 per sensor. That seems about right.  If wecompare the price of &D to 5D MkII, It is about $800 difference.
My personal opinion is that the Canon white paper is used to justify the high price of the FF body. The site of the FF sensor on the wafer may be 22 to 24. That will bring the yield up to be 6 sensor per wafer. and the difference in cost will be $770 instead of $1000.We are assuming that the wafer cost is $5000. Which is extremely high for a CMOS process. What if the wafer cost is $2500, than the difference  of FF sensor and APS_C snesor will only be $450 or even $370.

492
Lenses / Re: why????
« on: July 24, 2011, 03:51:37 PM »
why does no one make say a 16-50mm f2.0 or something similar for crop cameras sure it would be expensive but i think people would be willing to pay for it, i would pay 70-200mm is f2.8 is money for it.

On a side not canon should make an L-s range for good crop for lenses like this. i aim fairly certain within a few years full frame will be less popular with the ridiculous iso performance of  new crop cameras and the possibility of photo binning (don't ask me about it i'm a noob but basically you have option to reduce megapixels to get better iso performance)
The lens that you want  is an excellent walk around lens. However, it may be a monster in size and weight. just look at the 17-50 f2.8 EF-S. It is 4.4 inches long, using 77 mm filter and weights 1.4 lbs. If it was f2.0 and 16- 50 mm, it might be using 90mm filter or larger and weighed over 2 lbs easily.  The 16-35 already uses 83 mm filter. How many people will like to have a monster like tah tas a walk around lens and can be spotted from far away???

493
Canada / Re: Questions about crossing the border with your gear
« on: July 23, 2011, 02:26:19 PM »
May be I am lucky. I have been in most parts of Asia, Europe, Central and Southern America, the Nother Africa and  the old Eastern block including Russia. I have never have any problem going in or out with my camera equipments ( M4 and 4 lenses, canon DSLR and 4 lenses plus filters etc.) the bag may have been looked at couple times. In the old days I have a certified paper from the US custom for my Leica equipments. It is used to prove to the US custom that I have brought them out of US therefore I can bring them back in without any questioning. Nowadays, photo equipment is cheaper in US than most parts of the world. So the US custom has not looked at my paper for more than 25 years.

494
Canon General / Re: Canon Mirrorless Related Patent?
« on: July 21, 2011, 12:11:53 PM »
Racgordon,  You are asking for a brand new system with technology that does not exist yet, with all the bells and whistles and still want it in midprice range ($200??).Good Luck. Let us face it. as it it now, nobody even has made an EVIL or point and shoot with AF as fast as DSLR. The claim of fast AF of EP-3 has been shot down by a few people in the internet. Your dream EVIL may have to wait a LONG time. I suggest you get a S95 now. It have everything you want (pocketable, good image, zoom lens full control etc,)except the touch screen.

495
Canon General / Re: Canon Mirrorless Related Patent?
« on: July 21, 2011, 12:24:38 AM »
Is it fair to say that eventually the m43 route would just yield a cheaper M9 with an electronic viewfinder? Even though giiven the size of the 43 sensor and lenses designed specifically for it, I doubt the m43 companies can replace the 43 sensor with a FF sensor.
If there is another EVIL FF, the existing M4/3 EVIL player may be out of the picture. My reasoning is: 1. They got too much investment in M4/3. 2. If they replace theM4/3 with FF, that is almost admitted that they have made a BIG mistake. On the other hand, It is hard to have anybody to do a FF EVIL  from ground up due to the huge capital outlay and the patent right held by Leica for the offset micro lens to minimize the uneven explosure at the corner and the edge of the frame. Even Leica did not start the FF digital from ground up. It uses its existing rangefinder lens that is for M6 onward (Even lenses from M2 to M5 are usable in M9,  ALL Leica lens since day one of Lieca (since 1930??)are usable via a screw mount to M mount adapter). The wonderful view finder and range finder are move over from M7 also.



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