Messages

1606

EOS Bodies / Re: “1Dsq” & 3D [CR1]

« on: January 27, 2011, 03:27:58 PM »

Not to mention I wouldn't want to see the corners on a 36mmx36mm sensor with the lens that don't have the baffle on the back of them.

The image circle for a an EF lens would make a 30.6mm square sensor.  Sensor size would be constrained by the hypotenuse (43.266mm), not the width of a 3:2 ratio frame.  For the record, a 36x24mm sensor is 864 mm2, a 30.6mm square sensor is 936 mm2.  That is an 8% increase of surface area.  That, coupled with the fact that a square sensor would have less sensor area outside of the 'sweet spot' of the lens would likely result in slightly sharper images.

OK... now take your 30.6mm square sensor and crop it to a normal AR and you only have 30.6x20.4 and only 624mm^2.  Significantly smaller than FF, and just a smidge over APS-H.

So?
Why would you crop it to a "normal" AR?
And what is a "normal" AR?
3:2 because that's what 35mm film used?
16:9 because that's what wide screen TV uses?
4:3 because that's what a lot of computer monitors are?

If a 3:2 is always cropped in order to fill a 16:9, then what's the point of a 3:2 sensor?
If a 3:2 photo never fills a 4:3 or 16:9 screen, what's the point of a larger screen?

The point here being that aside from historical bias towards 3:2 there is no reason for digital photographs to be that way.

1607

EOS Bodies / Re: “1Dsq” & 3D [CR1]

« on: January 27, 2011, 03:15:12 PM »

"They don't need to build a whole new lens system."

Dilbert, make a circle that touches the edges of a rectangle with an aspect ratio of 1.5 x 1 then make a circle around the squares made up of the 1.5 dimension, and you'll see that the area of coverage is significantly expanded.

As other her noted the square will be smaller than the 1.5 dimension if they went that way but kept the current lenses. I'd say this has a snowball's chance in hell of being true, but hey, Canon have made some really bad decisions lately, like messing up the once wonderful G series, so maybe.

The flaw in your logic is that you're assuming the (new) square sensor will be just as wide as the current sensor.

There's no reason for it to be that way.

Click on and read the "many moons ago" story in that started this thread:
http://www.canonrumors.com/2010/05/the-cmos-sensor-squared-cr2/

Next time, read all of the article and the stories it references and links to first.

1608

EOS Bodies / Re: “1Dsq” & 3D [CR1]

« on: January 27, 2011, 03:29:25 AM »

I think the patents are a very pertinent point, and I really can't see Canon building a whole new system for the ever shrinking stills market. I bet that their focus will be on video all the way now.

Huh?

They don't need to build a whole new lens system.

1609

EOS Bodies / Re: “1Dsq” & 3D [CR1]

« on: January 27, 2011, 12:59:07 AM »

...
Ok, so let's see... Canon is going to bring out all new lenses for this square format sensor, and we haven't seen a single square format lens patent... right that does that one in.
...

Canon doesn't need to bring out all new lenses. The *only* lens that I'm aware of that isn't appropriate for the square sensor is the 24-105L/f4 because of the rectangular bit on the back. If they did bring out a square sensor, I would not at all be surprised if Canon also announced a program to "fix" those lenses.

1610

Canon General / Re: 70-300IS USM (non-L) now pointless.

« on: January 26, 2011, 03:19:57 PM »

This was indoors, ISO 3200 but here you can see what is the more significant difference: the chromatic aberration on the Tamron that's nowhere to be found on the Canon L. Although the composition isn't exactly the same, the point of this to show what I've mentioned above. In areas where the Tamron shows CA, the Canon doesn't.

I've not attached shots made with the Canon 70-300IS USM because they simply aren't even in the same ballpark at these two. How much of that is simply due to the IS on that lens not being as good as the two newer ones (and those shake produces less clarity) I can't say.

1611

Canon General / Re: 70-300IS USM (non-L) now pointless.

« on: January 26, 2011, 03:08:47 PM »

This shot was shooting out the front door of the shop. Unfortunately a car parked right outside the door between changing lenses so I couldn't get the same composition or subject matter to focus on.

Both lenses show good detail in the scratches in the car's bodywork. That's at 300/5.6.

1612

Canon General / Re: 70-300IS USM (non-L) now pointless.

« on: January 26, 2011, 02:47:36 PM »

ok, i was going to upload a couple of pics but various tools don't make it easy to select the middle 500x500 region of a pic.

dilbert, do you have photoshop?

yup... but I don't know how to use that to just get the centre area of a pic...reliably. I can crop with the cut tool, but that's not as precise as i'd like..

ah... change canvas size.

1613

Canon General / Re: 70-300IS USM (non-L) now pointless.

« on: January 26, 2011, 09:52:13 AM »

ok, i was going to upload a couple of pics but various tools don't make it easy to select the middle 500x500 region of a pic.

1614

Canon General / Re: 70-300IS USM (non-L) now pointless.

« on: January 25, 2011, 02:39:34 PM »

looking at Bryan's charts, I see the same thing as neuro.  what's maybe even more concerning are his preliminary comments regarding focus accuracy ... any time you hear those words regarding a telephoto ... yikes

This may be no different to the stories around the Tamron 28-75/f2.8 where people say there are "good copies and bad copies" - which speaks more to the variability in Tamron's manufacturing process.

But at $400 after rebate, the Tamron is a very compelling buy...

1615

Canon General / Re: 70-300IS USM (non-L) now pointless.

« on: January 25, 2011, 02:34:38 PM »

Popped into a camera store today, to look at the 70-300L IS USM ($1549) and the Tamron 70-300 VC Di ($449).

There's now no point in buying the 70-300IS USM (non-L).

Ok, so I agree with your thread title about the Canon 70-300mm IS (non-L).  Looking at a comparison of those two lenses at 70mm f/4 and at 300mm f/5.6, the Tamron is better (although neither is good at 300mm).

But, you are really talking about 3 (4 counting the Sigma) different 70-300mm lenses here, and you also seem to be saying that buying the new 70-300mm f/4-5.6L IS lens is pointless.  Or do I misinterpret the '$1100 for white paint' comment?  (Oh, and you forgot to mention weather sealing.)

Well, given that the new Tamron is significantly better than the non-L Canon and is significantly cheaper, the question needs to be asked, what do you get for $1100?

When TDP compares the Tamron 70-300mm to the new Canon L zoom, at 70mm f/4 the Tamron is a bit sharper across the frame (surprising, but the Tamron is reportedly a very sharp lens.  But, at 300mm f/5.6] (which is where you took your test shots) the Tamron lens looks, well, like crap, and the Canon is still quite sharp.   

So, are you saying that in your hands, the Tamron performed as well as the new Canon 70-300 L, or just better than the old Canon 70-300 non-L, or both?  If it's the latter, maybe you can show some 100% crops to back that up?  I know Bryan at TDP has a careful setup and from his testing, as you can see in the links above, the Canon L zoom is fairly similar to the Tamron at the wide end of the range (kudos to Tamron), but the Canon L is clearly better than the Tamron 70-300mm starting from 135mm onwards (which seems to result from degradation in the Tamron's performance as you zoom in, while the Canon stays sharp).

I'll upload some fragments of the shots I took. I see what you mean about TDP showing the L being much better than the Tamron/non-L. Part of me wonders there is variation in the samples... I'll add that I wasn't shooting test patterns so that will make it harder to judge how good it is/was because in none of the shots I took was the entire image in the same focal plane...

1616

Canon General / Re: 70-300IS USM (non-L) now pointless.

« on: January 25, 2011, 03:32:26 AM »

The 30-second review on the back of the camera showed little that I could discern between the two - at least in the center of the frame. I'll look more closely later when I load them up into LR.

Wow, I have to take your word for it then.

Sorry, but testing camera gear for 30 seconds in a store isn't much to go off of.

Do your homework and read reviews, look at sots taken out in the elements and talk to others online who have used it.

Loading the pictures into LR, the 70-300L has no perceptible chromatic aberration whereas it is visible with the Tamron. However, the Tamron's IQ leaves the old 70-300IS USM from Canon in the dust. (This was all at f/5.6, 300mm)

In terms of sharpness, I can find very little if nothing between the new 70-300s from Canon/Tamron.

So I'll stick with my conclusion that there is no longer any reason to buy the Canon 70-300IS USM f/4-5.6 because not only is the Tamron cheaper ($449 vs $549), but it is far superior in terms of IQ (I believe it lives up to Tamron's claims of being best in its class.) The only reason you would want to buy the Canon 70-300IS USM is if you wanted to say that you only had Canon lenses and/or could not stand the reverse rotation for zoom/focus.


btw, as for "reviews", photozone doesn't have one and neither does dpreview...

There's one here:
http://www.demystifyingdigital.com/Digital-SLR/Tamron-SP-AF-70300mm-Di-VC-Lens-Review/index.aspx
... that agrees with my conclusion.

DXOMark gives it 17 (on Nikon D3s), however DXOMark also scores the Sigma 70-300 APO DG at 21 (on D3s) and that's half the price of the Tamron.

The review here:
http://www.popphoto.com/lens-test/2010/11/lens-test-tamron-sp-70-300mm-f4-56-divc-usd-af
has nothing bad to say but they do not have a 70-300L review for comparison.

Another review here:
http://www.steves-digicams.com/camera-reviews/tamron/sp-70-300mm-f40-56-di-vc-usd/tamron-sp-70-300mm-f40-56-di-vc-usd-lens-review.html
is also troubled to find anything to complain about.

So what do you get for the $1100 premium for the 70-300L?
Heavier white paint, less to zero CA and the name Canon.

If you don't believe it, find a store to do some tests for yourself.

1617

Canon General / Re: 70-300IS USM (non-L) now pointless.

« on: January 24, 2011, 07:45:08 PM »

Popped into a camera store today, to look at the 70-300L IS USM ($1549) and the Tamron 70-300 VC Di ($449).

What do you get extra for $1100?

Heavy white paint.

The image stabilisation on the Tamron feels about as good as that on the new Canon and the IQ is similar too.

There's now no point in buying the 70-300IS USM (non-L).

Have you compared the image quality between the 70-300L and 70-300 Di DV yourself? I don't doubt that the Tamron is a good lens for the price, but I do find it hard to believe that it could come even close to the 70-300L.

The 30-second review on the back of the camera showed little that I could discern between the two - at least in the center of the frame. I'll look more closely later when I load them up into LR.

1618

EOS Bodies / Re: From the Land of Crazy! [CR0]

« on: January 24, 2011, 07:40:41 PM »

So...

This is a 1Ds2 in a smaller body.

It has been some number of years since the 1Ds2, so it should be safe to assume that the sensor performance will have improved. If it can do ISO 12800 like the 5D2 can do ISO 3200 then Canon may have a winner.

But...

WHAT WILL IT BE CALLED?!?!?!?!?!?!?!?! NO NAME!

1619

Canon General / 70-300IS USM (non-L) now pointless.

« on: January 24, 2011, 06:31:58 PM »

Popped into a camera store today, to look at the 70-300L IS USM ($1549) and the Tamron 70-300 VC Di ($449).

What do you get extra for $1100?

Heavy white paint.

The image stabilisation on the Tamron feels about as good as that on the new Canon and the IQ is similar too.

There's now no point in buying the 70-300IS USM (non-L).

1620

EOS Bodies / Re: 1Ds Mark IV.. The Saga Continues... [CR2]

« on: January 20, 2011, 01:18:48 AM »

<strong>“Total Garbage”………</strong>

….. that’s what I was told by a good source in regards to the recent murmurs about an imminent 1Ds Mark IV announcement.</p>
<p>The 1Ds Mark IV has been an <a href=\"http://www.canonrumors.com/2010/02/whats-coming-next-week-cr2/\">achilles heel</a> of mine, I am very cautious to post anything in regards to the camera.</p>
<p>The 1Ds Mark IV is a 2012 camera the source says, the final product has not yet been settled. There are 2 prototypes floating around.</p>
<p>I haven’t received the same info that I have in the past right before a big camera launch, I tend to think the 1Ds 4 isn’t coming in 2 weeks.</p>
<p><strong>5D Mark III</strong>

Spring 2011 announcement? Summer availability? 28mp?</p>
<p>That’s the latest on that one.</p>
<p><strong><span style=\"color: #ff0000;\">c</span>r </strong>

I think Canon (now?) know who your sources are and they are being fed information to control what appears on this website. The problem with this update is that it does explain or take into account the disappearance of the 1Ds3 from Canon's website, etc. Would Canon run for 12 months *without* a top pro camera? I think that the hit required for that is bigger than their corporate ego can stomach.