Thanks Herb, I understand your point but only as it regards like sensors of diffrent sizes. The first FF sensor was the 6MP Contax and the images at 400 were worst than my 5 mp Oly E-1 at 800 which has a chip about one fourth the size of the Contax chip.

Phil

Yes. It only strictly applies to sensors of the same design and process just scaled up. I don't have any details on the relative merits of the Canon vs Sony processes and circuit design. So if they were to make a FF D3x with the same process and design, you can expect one stop better signal-to-noise.

Your experience with the Contax surprises me, but maybe that's why they are out of this business.

It is sad, I have a Contax N-1 (35 mm) and the glass is wonderful.

Go to Pentax and look at the smcp-FA 645 120 mm F4. This is a macro lens that shots life size, 1:1 in 645. Life size image on 645 film or sensor. E-ray does the same thing on film over 12 inches wide. Image is still life size.

My Oly E-1 shots life size, 1:1 (the 4/3 chip size or about one- fourth 35 mm size) with an extension tube. In 35 mm that would be called 2:1.

Phil

I suspect that the 1:1 claim of the Canon 60mm lens is based on the 35mm format, even though it mounts only to EF-S camera, thus yielding greater than 1:1. Otherwise the degree of magnification would be less than the 1:1 of the 100 macro (which IS based on 35mm), and offer even further confusion to the lens lineup!

add my 2 cents .. i would rather have a 1d mkII ....... that killer speed and pro body ... the Ds may have resolution and full frame but its price is out of my league ... and besides the 1d is still a massive choice for pros in the world

5D - it's all about resolution and FULL FRAME. Full frame, in particular, is a Very Good Thing. Many non-Canon shooters seem to have forgotten this point, but it's actually sort of nice to shoot your 17mm lens at 17mm again etc. And I believe that a bigger sensor is a better thing - I'd like a 6*9 sensor rather than a 35mm size sensor if possible!

So anyway, that's what your paying for with your 5D. It's certainly not cheap considering the build quality - you're getting a 'consumer' body and autofocus. But there's been a lot of demand on the forums for full frame at an 'affordable' price, and this is Canon's response.

I still think it's a pretty good underwater camera, as long as it can be made to fit inside existing housing moldings (unlike the 1 -series, which are substantially bigger and thus seem deprived of sensibly priced housing solutions).

Topside I'm not entirely convinced that it's better value than a 1Ds, but that's probably just because I'm bitter that my 1Ds is now devalued to the point where's it's worth about the same as my Yashica Electro (that's not very much, BTW).

Another point to consider - with some of the cheaper housing systems, there have been concerns re: corner sharpness on crop sensor cameras. Full frame potentially makes corner sharpness much more of an issue.

I will resist the temptation to add more bird pictures to this thread. I still reserve the right to post brick wall photos, however.

Personally for me full frame vs cropped sensor is not really a big issue. More important issue is how well it is executed. Nikon already took care of the wide angle disadvantage with 12-24mm and 10.5mm DX lens.
Full frame, at equal pixel count to cropped sensor (all else being equal) theoretically will have advantage in digital noise level but if Nikon can manage somehow to keep the noise level down to an acceptable level, especially when compared to the full frame counter part then I don't see cropped sensor as a disadvantage beside having to do a little math when trying to figure out the lenses.
The trade off of higher noise level especially at high ISO vs problem with seeing deficiency in the periphery of full frame glass is not a dealbreaker for me as far as cropped sensor is concerned. If Nikon decides to stay with cropped sensor for their next 18-20+ mps camera, I have no problem with that as long as they can somehow make the sensor works and keep the noise down. If they can't then they probably be better off going full frame.

If you fill the frame with the subject on both a D2x and a 5D there should be very little differences in most cases. Of course we'll have wait until we see a detailed review of the 5D to compare, but I would be a little surprised if there's much of a difference.

At small apertures, the smaller, higher density, sensor will be limited by diffraction more than the larger sensor. It's a little complicated to sort out but the larger sensor has an advantage on macro subjects where you shoot to get the same print size and depth of field.

I am not sure if I understood you properly. A lens doing 1:1 is recording the subject 1:1 and has so far nothing to do with relation to certain sensor/film sizes. The only thing which is true: if you shoot a small subject 1:1 which fills the smaller sensor (APS-C) entirely, you would require a 1,5:1 (Nikon) or 1,6:1 (Canon) lens in order to fill the full frame sensor in the same way with the same subject.



I still know some film shooters who really like their fast primes (in which they have invested a lot of money) a lot. Some of them consider switching to digital finally, but not all of them would be happy to exchange several f2.8 primes (14mm, 20mm, etc.) for those few and slow APS-C 10/11/12-20/22/24mm zooms. Add the price for a new APS-C fisheye and the 5D is already a quiet good deal. I don't say these zooms aren't good, but some people who would spend the money for cameras like the 5D might love to continue using their fast glass. From one point of view I would even prefer APS-C wideangle zooms because the have a lot more DOF than a full frame lens with the same FOV and therefore perform better behind dome ports in this respect. But I can not confirm that FF wideangles deliver poorer corners in general. I think we have been spoilt by FF lenses on cropped sensors where corners weren't critical because the lenses had been designed to cover a larger image circle. But APS-C lenses have shown the same effect now as they “just” cover the used image circle, like FF lenses with slides or FF sensors. I can not see the Canon EF-S 10-22mm beating all full frame L glass wideangle zooms and fast primes (17-40mm f4, 16-35mm f2.8, 20mm f2.8, 24mm f2.8, and so on) to replace them with just one slow zoom. I am sure Nikon shooters had more wideangle choices when shooting slides than “just” one equivalent 18-36mm f4 (12-24 on APS-C). I am sure Nikon will add more good glass to their DX line but for the time being, it’s not the worst thing if you switch to digital and simply continue to use your existing glass which is not only available now, but already owned.



With film bodies it was simple, the next more expensive camera was better in most every aspect (frame rate, build quality, etc.). Resolution and sensor size was the same with all cameras: film. With digital we have to face different models being different kinds of compromise between the old days’ criteria and the digital part of the camera (sensor size / resolution). 5D’s priority is nothing but FF and resolution. So I would not say it’s odd that it doesn’t feature certain things just because of the high price. A 5D with Nikon D2X body and features would not be available for 3000 bucks, the 5D sensor is much more expensive than the D2X sensor. On the other hand a studio photographer with no requests to speed but resolution could say the Nikon D2H is so overpriced, just 4 megapixels for the same price like the 5D? Different Cameras for different users with different preferences, hourses for courses. Judging from the very first responses, it seems that the 5D could be a quiet attractive compromise for Canon underwater shooters.

Julian

Interesting Idea. The S&S Housing is pretty big (What i first disliked but now like) so it is a possibility. I will do a Measuring on the Weekend when I have the Housing Back from the Suitecase of my Girlfriend who is still in Spain (had to put som weight to her suitcases)

But probably you have to change most Buttons and i don't know if this is

- much less expensive than a new housing
- Good for the future tightness of the housing

Anyone did something like this in tha past?

Do you mean topside or through a dome port, Julian? Pretty much all lenses, and all the practical underwater options, will be a bit soft in the corners on full frame when shot wide open in above water use. If you want really sharp corners on the 5D, you're pretty much talking Zeiss 21, Zuiko 21 and Leica Elmarit 19mm - but I don't think you want to take any of these diving. In reality, the corner performance of something like the 17-40L would be fine for underwater use from the point of view of the lenses' optics.

I do wonder whether the softish corners (from the dome port, not the lens) that I see when shooting underwater on the 10D would be significnatly worse if shooting full frame. Even if Ikelite for example decides to house the 5D, I'm figuring that there's no experience available in using a port system like this for full frame. I guess I'm thinking that all the issues like nodal point etc would be magnified if we're using the full lens and not just the centre crop.

If this is the case then Canon should step up and call the lens what it is a 1:1.6 macro.

Phil

Rob,

as said, when leaving dome effects out for the first.
So what EF-S lenses would you suggest to deliver better corners than 17-40L, 20 f2.8, ... on full frame? Do you expect the 10-22 to be better on a high resolution 1.6 sensor (which doesn't exist from Canon) than the others on full frame?

As said, the dome is a factor as it requires DOF for wideangle corners. FF lenses call for large domes.

Julian

Like the issue of life size (i.e. 1:1) full frame has nothing to do with 35 mm. Any lens that was designed for the sensor being used makes the sensor a full frame sensor. A 645 lens used with a 645 sensor is full frame. Canon has four EF-S lenses, 60 mm macro, 10-22, 17-85, 18-55. These lenses are designes for the so called 1.6 sensor and don't work on the 1.3 sensor or the 35mm sensor. That makes the 1.6 sensor full frame for those lenses. Nikon has six DX lenses that don't work on 35 mm, these lenses make the 1.5 sensor full frame. Olympus has nine digital only lenses and four more on the way. They only work on the 4/3 sensor and no 35 mm lens is even made that will fit the lens mount. That makes the Oly lens sensor combo clearly full frame. I admit that most camera users come from a 35 mm backgroung but that in no way makes 35 mm the standard by which all other formates should be judged. I have a Pentax 6 x7 camera for some types of work where I need a large neg. If I used that as the standared 35 mm would have a X2 crop factor. Regarding 35 mm sensor v 1.6 or 1.5 with like angle of view lenses. Go to Steve Frinks review of the 17 to 40L on a 35 mm sensor and the review of the Nikon 12 to 24mm
on the Nikon high end 12+ MP sensor. Results show the smaller sensor giving the better image.
I beleave this is because the 17 to 40 was designed for a film camera and the 12 to 24 was designed for the 1.5 chip. If you read the date regarding many of the high end designed for digital lenses you will find that the elements are of a diffrent design from film lenses. Also that the wider the film lens the worst the preformance of the lens in the corners, land or sea. See Steve Frink test of 16 to 35L mm v 17 to 40L on 35 mm full frame.

Phil

The term full frame is used more than regularly for describing a DSLR recording surface of equal size to 35mm film, from the industry too. Of course you may argue if you find this term misleading.

The problem with larger image recording size for underwater is the shallow DOF because we shoot thru simple curved glass which actually is not a consistent optical underwater system. Again, the problem remains especially with wideangles in the corners as the dome’s virtual image is curved, not flat. Corners are closer in terms of focus distance. So they have to be covered by DOF. That’s why dome glass didn’t work well with medium format wideangles and things like the Ivanoff underwater optical corrector have been used instead. I agree that on an identical dome setup the APS-C lens (same FOV,etc.) performs better. But the reason is not the general opical disadvantage of the 35mm format, it's the hosuing optics which are very poor compared to any decent wideangle lens.
By the way, this does not apply to fisheyes because they focus in a manner the dome’s virtual image is shaped. Fisheyes have always been less critical underwater in the film past too.

What I was trying to say to Rob: A lot of people complain about 35mm sized sensors delivering poor (wideangle) corner performance. I think this is often meant in comparison to APS-C DSLRs with 35mm lenses because the weak corners are cut away. But you loose the FOV too. IMO you experience the same with an APS-C image chip and APS-C lenses as they capture the entire lens’s image circle too, including critical corners at the edge of the FOV the lens was built for (we talk about extreme wideagnles around 100° FOV). I’ve seen poor corners with both formats, 35mm with 35mm lenses and APS-C with APS-C lenses. And I am not sure that every APS-C zoom must outperform any 35mm lens (prime/zoom) in general.

Don't know the tests you have mentioned. I guess they are in conjunction with underwater usage incl. domeports? or lens only tests? Maybe you could post a link? I found this quiet interesting:
http://www.wlcastleman.com/equip/reviews/17-40/union.htm

Julian

edit/ps: 17-40 for designed for digital 35mm sensors. The older 16-35mm was film only in mind.

Regarding the industry use of the term full frame the industry also uses the term life size or 1:1 in regard to 35 mm as well, I have no argument regarding this other than to say it is in fact misleading.
It was not my intent to suggest that all digital specific lenses are better than all film lenses.
I just wanted to point out that the evidence is becoming stronger that lenses designed for a digital sensor type appear to be gain ground over lenses designed for film. Which leads to the question will 35 mm film lenses need to be replaced by 35 mm digital lenses for the 35 mm chip to achieve max image quality?
The Frink tests can be found a seacamusa.com in the Tech Notes section.
Regarding corner sharpness, all things being equal should I expect that when my Olympus 7 to 14 mm zoom (14 to 28 mm 35 equiv.) dome port arrives in the next month or so that I should expect it to be the sharpest lens of all in the corners because it has the smallest SLR sensor and therefore the greatest DOF?

Yes, I agree there is some work to do with both formats. 35mm wideangles should be overworked to meet nowadays’ digital 35mm SLR bodies (5D / 1Ds) requirements. An increased choice on APS-C lenses (more zooms, fast primes, etc.) is important too.

As a Canon shooter, I would prefer the 35mm lens choice over EF-S - from what is available now. As said, I am really afraid EF-S won’t become an extensive lens line-up like Nikon’s DX series.

4/3” 7-14mm: Well, I don’t expect Olympus will ship you an adapted Seacam Superdome with E-300 housing mount
But yes, if everything else would be absolutely identical, 4/3” wideangles have a dome corner advantage in terms of DOF.

Julian

Did you guys check the 5D samples at the Canon site? The colors are awesome, but I noticed soft corners on the landscape shot. I don't know which lens was used, the exif only says 17mm, I am guessing the 17-40.

http://web.canon.jp/Imaging/eos5d/eos5d_sample-e.html

EXIF says 17-40.
The grass looks like mushy water color in the corners. A little better nearer the center. Actually that landscape shot is not that great... but the portraits are amazing. Pretty typical of digital outresolving WA lenses.

this sample doesn't look good at all. I really hope this is not representive for the 5D + 17-40mm. I am not surprised by the corner softness, it's 17mm (93°) and somehow all extreme wideangles produces such corners, especially on this kind of high resolution cameras. But the rendered colors and details look strange. I sometimes wonder why manufactures put such samples online to promote their gear, even if they are real . Most worse I have seen is a Olympus 7-14mm sample from the manufacture itself:
http://www.olympus-esystem.com/dea/product...ge/sample08.jpg

... and this is just a 5 MP camera not demanding this 1800 bucks lens to strong. Like the Olympus lens, I hope the 5D/17-40 will do better in real life too. Otherwise it's a bit dissapointing.

Julian

The Seacam dome would be beyond great and you could throw in a 180 enlarged finder at the same time. My guess is that the dome will be a 170 mm Athena glass on the Oly mount with the removable extension tube for the zoom lens. The FF 8 mm fisheye coming in Jan 06 is a 180 lens and projected at around 153 degrees under the dome without the tube and focus to 2 mm from the dome.
For a $1000.00 housing the viewfinder is not half bad.
you can see my post regarding this housing in the E-300 post in this forum.

Phil

Ok, maybe I can help resolve this issue.
I have a Canon 350D with a Canon 60mm EF-S lens sitting next to my desk that I use for work.
I set the camera for f8, 1/100, iso1600. I set the lens to manual, minimum focus (all the way left). I then photographed this ruler at what I estimated to be the sharpest focus I could achieve by moving the camera in and out. Here is the result:



This shot has not been cropped. I've only resized it to fit this forum.

Units are in inches. I estimate the total width to be 13.5 x 1/16 inches = 0.844 inches = 21.4 mm
The 1.6 crop sensor in the 350D is 22.2 mm across but not all of it is used.

I think this answers the question concerning 1:1 and the relevance of 35 mm equivalency. A 35 mm equivalency is not used when rating this lens. The image is the same size as the cropped digital sensor at 1:1.

-Brad

Thanks Brad! I'm surprised that canon departed from the 35mm convention! So the 60mm lens gives signficantly less magnification than its FF cousin.

Kasey, I don't understand what you mean by this. Canon did what I think is the correct way to state a spec: 1:1 magnification means the image is the same 22mm as the subject. The 60mm lens has exactly the same magnification as the 1:1 100mm macro which was made for 35mm cameras.

A subject 22mm completely fills the 22mm frame rather than a 35mm subject. If he makes a 8x12 print from this shot the 22mm subject will come out 12 inches high, in the 35mm case a 35mm subject will become 12 inches high. The magnification would be GREATER if Canon were to state this in 35mm terms. See why it's so confusing to keep translating things to 35mm frames.

Herb - if a 35mm lens is rated at 1:1 (as is the 100mm), it will provide greater than 1:1 magnification when mounted to APS - agreed? On APS the image circle is cropped leading to an apparent higher magnification.

All my micro Nikkors are rated at 1: 1 (35mm) but yield greater magnification on the cropped sensor.

In turn, the EF-S 1:1 lens offers only 1:1 magnification on the cropped chip. It provides less magnification than mounting a 35mm macro lens to the same body.

I think that this is confusing as a consumer - mounting the 1:1 100mm lens to my 20D yields greater magnification than mounting the 1:1 60mm EF-s to the same camera.

Kasey. I think I see your point of confusion. Your last statement is incorrect. You will get exactly the same image that Brad got (no more no less magnification) if you mount your 100mm lens on your 20D. I've done the test with the same 100mm lens on my 300D. The 60mm and the 100mm has the same max magnification. Just ignore the fact that it's an EF-s lens and not usable on a FF camera.

Canon, the lens maker, is giving the correct spec 1:1 on the two lenses which has identical max magnification. The size of the "usable image" is not part of the spec; it's implicitly know that it's 35mm in one case and 22mm in the other.

The confusion comes from the fact that you're interested in magnification in the final print, which involves magnifying the image on the sensor to print size. You are making a larger magnification to go from the 22mm sensor to print vs the 35mm sensor. This is not included in the spec of the lens. The lens magnification spec only covers the part of going from your subject to the sensor (that's the only function of the lens); magnification from sensor to print is NOT included.

No, when you crop (be it in a sensor or in photoshop) you don't increase magnification, you change the field of vision. So, 1:1 is 1:1 in 35mm and 1:1 in 20mm or whatever the measure of your sensor is, we just change the field of view.

In other words, if you take the same lens (say a non EFS 60mm), and make the ruler test (the same already posted here), you will photograph a 22mm (or 21.4 as demonstrated) long stretch of the ruler with the 1.6 cropped camera (dRebel or 20D), meaning that it is a 1:1 lens because it photographs an object that has the same size of the sensor. If you take the exact same lens and mount it on a full frame (35mm sensor) camera you will photograph a 35mm long stretch of the same ruler, still meaning that the lens is 1:1. You didn't change the magnification, just the field of view.

EDIT: Herb, you posted when I was typing, beat me! We are giving the same answer here.

No, Julian, he may not argue if he finds the term misleading. It's bloody well called full frame by everyone, so he'd better get used to it! FWIW, tropical, your pentax 6*7 is crop sensor also, given that I shoot MF at 6*9.

Anyway, I've previously posted brick wall shots on Wetpixel of the 17-40L at full frame re: corner sharpness. Please don't make me do it again! Wetpixel briefly consisted of nothing but peoples' wall shots - personally I like looking at fish and reefs and stuff better.

The point is this. A lens like the 17-40L on a full frame DSLR will peform very nicely, if you stop it down a little. If you pixel peep, the corners are still soft at f8 to f11, but not so you'd notice on an underwater shot (compared to the distortion and softness once a port is involved). It's not a problem of digital lens vs film lens - it's a problem of the sensors on the Canon 1Ds series (and now hopefully the 5D) producing files of medium format quality, through a lens designed for 35mm film use. In short, Canon's state of the art full frame sensors outressolve nearly all lenses. The three I mentioned above are some of the few (third party) lenses that are good enough to match the current generation of sensors. (They're not really suitable underwater as they're all manual focus/manual aperture - and I don't think the UW pics would be any sharper anyway).

I use the 17-40L on the 1Ds for 80% of my topside shooting. It's not perfect (and I'm looking for a sharper wide lens as we speak), but it's pretty damn good IMHO.

Just to wade in with my own OBSERVATIONS (not derived from anything other than using the lenses). I've used both the Nikon 12~24 and Canon 17~40, topsides and below. Out of the two lenses I prefer the 17~40 for a variety of reasons, although both exhibit corner softness at times depending on a whole host of factors (it really is not as simple as what size sensor the lens is used on as there are cosiderations regarding sensor pixel density, pixel size, etc., etc.! - The theory is not over complex but there are a lot of variables).

But to get back to the REAL WORLD. My observations on wide-angles in general is that the high MPixel cameras will show flaws in virtually all of them whether used underwater or not. I currently use a Canon EOS1DS - not the MkII - and have consciously decided NOT to upgrade it (in fact I've bought a second body, and will add more when used prices drop further). This is because I find that the quality it is capable of surpasses 35mm and to be blunt it is all too easy to enter technological overkill based on the numbers game. I have printed shots to 30in x 20in off the 1DS and 24/1.4 (a stunning lens with an extremely bright viewfinder image - another consideration?) and whilst I suppose that they could hold marginally more detail, you'd have to look pretty close. As has been commented here, the real problem with underwater wides is the dome optic. Currently, the bigger the dome the better the quality is a pretty reasonable statement. Perhaps manufacturers could look into seeing if a better alternative may be now built - I am trying to persuade a lens designer friend to look into the problem using lens design software, but this requires a lot of input which he can only do out of interest. One day.......!

I actually don't think Kasey is confused at all - I think he's got it exactly right.

Now I don't have the EF-S lens, but I understand that it produces '1:1' image size on the APS-C sensor (as compared with the size of the subject), correct?.

A lens that produces 1:1 (Canon 100mm, Tamron 90mm, not the Canon 50mm which is 1:2) on 35mm format will produce greater apparent magnification on a crop sensor camera. We all know of course that it's cropping rather than magnification that's happening here, the the fact remains that absolute size in mm of the image on the sensor will be different between the EF-S and the EF lens, ergo the degree of magnification is in fact different.

Here's the point of confusion that I was trying to point out. There are TWO magnification steps between the subject and your print: subject to sensor, and sensor to print. The lens makers are just giving the spec for their part which is subject to sensor. 1:1 means subject size equal image size on the sensor and does not depend on sensor size. The 1:1 EF lens and the 1:1 EF-S lens has the SAME magnification. Canon can change the 100mm EF lens to EF-S tomorrow by changing the mount and not the glass and the 1:1 spec, the magnification, would NOT change.

The magnification that is different is going from sensor to print which is NOT spec by the lens maker.

Well, I don't take it so far as the print in my analysis. Lets just go as far as the viewfinder. When I look through the viewfinder of a 1:1 Nikkor mounted on my F100, what I see is lower magnification than the same lens mounted to my D2x - on the d2x it IS beyond 1:1 in my viewfinder.

I think we are saying similar things differently, but my real question is answered by Herb - the 1:1 lenses give identical magnification.

Here is food for thought:
A 1:1 medium format lens is mounted to a 35mm camera. The viewfinder will project a 4:1 (approx) magnification of the subject. If that same lens were designed native to the 35mm, I think that the lens designer would market it as a 4:1 lens. I disagree that the stated ratio of the lens has nothing to do with the size of the medium on which it projects.

A corollary to that - the projected image of a 100mm macro is at least 35X35, yet it is the 24X35 crop that is 1:1. Clearly the lens designers do consider the medium and the viewfinder.

Kasey, taking your medium format example, a real 4:1 lens can fill the frame with an object four times smaller than the camera's sensor. That does not happen with your medium format example, if you take a medium format 1:1 lens and mount it on a 35mm camera it will not be able to fill the frame with an object smaller than 35mm. The numbers (1:1, 4:1, etc) mean subject to sensor ratio, not subject to viewfinder ratio, and I think you are mixing those numbers.

OK - I think Luiz and Herb are right from an optical standpoint, and we are talking lens optics after all. But in a practical sense, what I see in the viewfinder IS what my sensor sees, and the same lens on a smaller format yields greater magnification. If the resolving power of the APS chip is equivalent to a 35mm slide, the net effect is a "crop" with full 35 mm resolution. Same as putting a 1.6X teleconverter on my 35mm lens - yields greater than 1:1. Thanks for clearing up this point!

Rob & Paul,

this was exactly my point. Soft corners increase with larger FOV lenses and with high resolution cameras. IMO it is not predicted by the sensor size physically. As Paul said, you get soft corners with every extreme wideagnle and high resolution camera.

@Kasey:
See it simple, 1:1 means nothing more or less than this: captured subject has the same size on the sensor/film like in real life, that's it!

in other words:
You have two images. One image is in real world in front of the lens. The other image is behind the lens, projected on your sensor/film. 1:1 means that everything has the same size in both images.

If your sensor is 20mm x 20mm, a subject with 20mm x 20mm will fill the frame.
if your sensor is 36mm x 24mm, a subject with 36mm x 24mm will fill the frame.
But the sensor size has nothing to do with the magnification ratio. If it is 1:1, it is always 1:1, no matter on what sensor/camera you are going to mount it.

Only thing important to us when using smaller sensors: If you shoot a subject which fills the APS-C sensor with 1:1, you would need a 1,6:1 lens on full frame in order to get the same subject to fill the frame (final print).

Julian

Life size, (1:1) is life size on any media be it APS-C sensor size or 8"x10" view camera and full frame is full frame when the size of the sensor or film is the size for which the lens was designed.
Regarding 4:1 magnification of the subject this is a bit misleading as well. when you go from 2:1 to 1:1 the area increase is four times not two times. The subject area is twice as wide and twice as tall, that adds up to four times the area of the 2:1 inage. If you go from 1:1 to 1:2 the image is twice as tall and twice as wide, which is four times as large. If you have a 5 MP camera and want the image to be twice as big that would be twice as wide and twice as tall or 20 MP. If you look at a 1:2 framer for a Nikonos compaired to a 1:1 the 1:1 is twice as tall and twice as wide, 1:2 same 1:3 three times as tall as 1:1 and three times as wide. These rules don't change between film and digital and they don't change between format sizes.

Phil

Bob, I know the common use of the term full frame is understood by most to mean 35 mm full frame. But if you will keep an open mind and go to this Kodak link you will see several full frame sensors made by Kodak and sold by Kodak as "full frame" sensors that are not the same size as 35 mm. Since Kodak makes them and Kodak sells them I feel Kodak would know what full frame means. To say that the 35 mm size is the only size just because it is the most common size is in fact wrong.
Phil

http://www.kodak.com/global/en/digital/ccd...amilyMain.jhtml

Of course Herb Ko is right about the magnification factor. 1:1 is 1:1 no matter what camera you mount it on.

But I think the real question is what direction the DSLR is heading. With a less expensive full frame camera from Cannon will the 20D replacement be full frame too? and what will Nikon's response be? Will Nikon go to full frame or not? How about the smaller players? Olympus has bet on an even smaller format 4/3 with all new lenses as well.

Comparing the D2x and the 5D you have a pretty good comparison from a sensor point of view (although the D2x body has more features and more cost). Both are 12 mp but Nikon crams more mp into a smaller sensor.

On the APS side you get:

1. Effective magnification through crop factor (that goby I took at 12" from the port is bigger on the screen at 12mp that it would be with the FF setup).
2. Better corners with FF lenses. (You loose this advantage again when you go back to wide angle and need DX lenses).
3. Less expensive sensor
4. Somewhat smaller lenses (but the lenses I've seen aren't much smaller)
5. Better DOF (take this in combination with the crop factor and Macro shooting is much improved)

On the FF side you get:
1. Bigger viewfinder. (I haven't seen it yet but Phil raved about the 5D viewfinder)
2. Lower Noise (should be lower with biger photosites)
3. No specialty DX lenses for digital or film only.

It will be interesting to see if the 5D will turn out to have lower noise than the D2x or not or weather it even matters. DSLR noise is already so low that it might not even be much of an advantage.

Thoughts?

Depending on your assumptions, #5 is wrong in the important case of DOF limited macro shots. I assume by better DOF you mean larger DOF. For a given resolution, larger sensors will let you use smaller apertures before diffraction limits the resolution. This more than offsets the effects of having a longer focal length lens (which decreses DOF) to achieve the same field of view. Larger sensors have a net advantage in macro shots where DOF is a limiting factor.

If you think the noise on your DSLR is better than needed, you can trade it off for lens performance by shooting at higher ISO and smaller aperture. It was part of the point I was trying to make earlier, about FF effectively gives you a stop in lens performance all else being equal.

I just heard that Canon was just joking, there is no 5D

Come on folks - the debate over FF vs smaller sensors will rage forever if we're not careful!

The bottom line is that the smaller sensor will finally run out of steam in the MPixel department whilst it will always be (theoretically) possible to cram more pixels into a bigger sensor! Base common sense.

Whether it is worth taking either format to its theory limited specification is another question.

With the 5D, Canon have (much to my surprise) decided to head for a semi-pro/enthusiasts FF camera which should be very well worth housing. I doubt very much whether most people are going to look at a large print from a D2X and compare it with a large print from a 5D and comment on the difference. It is us as photographers who will notice the difference in using the cameras and which camera you choose is based on many other factors than final output quality.

I actually think that we should spend more time looking at solving the optical problems of domes and even chromatic problems with flat ports than arguing about sensor size. As you may recall from earlier posts, I'm not satisfied by the wide-zooms currently available (the 17~40 is about the best I've tried) and will be very interested to see what developments take place here. If Canon or Nikon produce a zoom which has less optical shift as its zoomed, is of fast aperture and preferably has IS or VR then I would say that this would have a great deal more bearing on which camera to house than does sensor size or many of the other theoretical considerations.

I look forward to trying out a 5D if I can get my hands on one!

No one replied to my question - if the EF-s 60mm macro is A) not smaller not cheaper - why would canon make this an EF-S lens??? ANy thoughts?

To get back on Topic: there is a Hands on Review at DP Review.

From the Hands on Review linked above:

Joe, what are you talking about? This thread has had nothing to do with the 5D for about 3 pages now......

My thoughts on your question are that the new 60 mm is as close as you can get to a 100 mm macro for 35 mm. Nearly the same angle of view and what appears to be life-size for the x 1.6 sensor. The 35 mm, 100 mm macro endsup having the angle of view of a 160 mm film lens and the 50 mm ends up at an 80 mm angle of view and is a 1:2 lens without the extension tube. Can't help but think that a lens designed for the x 1.6 sensor would also give advanced performance over the older film lenses.

Phil

Was just reading Reichmann's 5D review, here's a quote pertinent to our recent discussions...

Full Frame Good. Full Frame Bad.
Now, I know that the on-line forum natterers and nay-sayers are going to have a field-day debating the pros and cons of full-frame vs reduced frame. Well, all I can say is – walk a mile in the 5D's shoes and we'll see what you really think.

Anyone that shot film with an SLR prior to digital knows how frustrating looking though the smaller and dimmer viewfinders of most 1.5X and 1.6x digital cameras can be. Looking through the viewfinder of a full-frame camera like the 5D, by comparison, is like taking a whiff of pure oxygen. The image will be big, and bright, and yes, did I mention that it's full frame?

Which of course will be the topic de-jour online. Lots of folks will posture about how reduced frame cameras are better because they crop out the soft corners of some lenses. They'll also carry on about how 1.5X and 1.6X cameras give you greater reach with telephoto lenses (ya, right).

But, the reality is that with the exception of a handful of special lenses released over the past year or two that are designed for reduced frame cameras, the millions of lenses out there project a bigger image circle, and being able to use that image circle is a wonderful thing for a great many reasons. True, a high resolution full-frame camera like a 1Ds MKII, or now 5D, will mercilessly expose the true qualities of poorer lenses, but such is life. I don't know a single professional photographer who uses a reduced frame DSLR for any reason other than size and price, or because that's what's available in their preferred camera maker's lens mount. The 5D is going to alter that equation, and the industry is never going to be the same again.

Here's the link:

http://www.luminous-landscape.com/reviews/...-announce.shtml

If anyone still objects to me calling the 5D full frame by the way, I note that as well as everyone else in the known universe using this term, Canon uses it liberally on their 5D page.

http://consumer.usa.canon.com/ir/controlle...=11933&pageno=0

Bob, I don't object to the use of the term full frame for the fine Canon 1Ds and 1Ds mk2 cameras or for the new 5D, thats what they are, full frame. But the Olympus E-1 and E-300 cameras are also full frame. The backs being produced for 645 are very close to full frame, see Wetpixel home page for the one with the X 1.1 lens factor. All I have been saying is that about 3000 readers have come to this thread to learn more about photography and they many want to know the diffrence between what full frame means and what a 35 mm full frame sensor is.

Phil Rudin

But why not use the regular mount so it can project onto the 35mm sensor as in the 5D? It seems that canon is saving itself a few bucks and not passing to the consumer - can't think of any other reason...