D60 + 100mm f2.8 macro - DPChallenge Forums

04/18/2003 03:25:45 PM · #26

It'd make more differnece if you're using 35 mm, but you're using a 1.6x DSLR which makes the DOF larger.

Originally posted by Gordon:

No, I think I'm talking bollocks.

you'd have to halve the subject distance for the 50mm to get the same size, but stop it down a lot more to get equivalent depth of field.

So in general the 100mm gives more depth of field options, as you can work further away hence more dof for the same aperture ? Somehow this seems wrong, but the tables seem to agree.

04/18/2003 03:46:44 PM · #27

Originally posted by paganini:

(Only digicam users like infinite dof :) because it's really easy for them to get it)

Originally posted by magnetic9999:
yes. exactly. it (the 100mm) has shallower DOF. but who ever wanted less DOF on a macro? you always want more ;).

Originally posted by paganini:
Yes, but 50mm macro is only 0.50x life size unless you get the life-size converter. 100mm macro is 1.0x AND has shallower DOF. You basically get similar DOF shutting it down at F16 and adjusting the distances.

Slap on a 250D filter and the 100mm will be about 1.3x or 1.5x lifesize (forgot which one)!!!

Message edited by author 2003-04-18 15:49:28.

04/18/2003 03:48:45 PM · #28

Usually more DOF is a good thing for macro, but sometimes it isn't. It all depends on what you are trying to do!

Greg

Gordon

RIM BlackBerry Curve

Canon EF 85mm f/1.8 USM

04/18/2003 03:55:28 PM · #29

I think appropriate DoF is the key for macro, as with all shots.

It is something that a lot of people don't seem to have an appreciation for, however.

DoF is just another way to bring attention to the subject. Wish people would appreciate it more though!

04/18/2003 03:57:57 PM · #30

Originally posted by magnetic9999:

The ability to have more DOF on a macro is very desirable - whether or not you use it on a particular shot - it's good to be able to have it for those times when you shoot REALLY small things and you want more than a razor thin region in focus. Your generalization about who or what likes what is merely that - an uninformed generalization :)

Originally posted by paganini:

(Only digicam users like infinite dof :) because it's really easy for them to get it)

Originally posted by magnetic9999:
yes. exactly. it (the 100mm) has shallower DOF. but who ever wanted less DOF on a macro? you always want more ;).

Originally posted by paganini:
Yes, but 50mm macro is only 0.50x life size unless you get the life-size converter. 100mm macro is 1.0x AND has shallower DOF. You basically get similar DOF shutting it down at F16 and adjusting the distances.

Slap on a 250D filter and the 100mm will be about 1.3x or 1.5x lifesize (forgot which one)!!!

04/18/2003 04:02:05 PM · #31

That's true. But how many times have you gotten a comment HERE that says "too bad xxx behind the subject is blurred?" :)

Originally posted by Gordon:

04/18/2003 04:31:06 PM · #32

the generalization was that 'only digicam users like infinite DOF'. the reality is that deep DOF is desirable in may fields of product, commercial, and scientific photography. Hence the proliferation of very powerful lighting and specialized systems that allow product shots at f/16 or higher :).

In my own job, I photograph museum artifacts - it's a requirement to get the entire object to seem sharp: no shallow DOF. With tiny archaeological artifacts this is occasionally a problem. I usually have the 400W work strobes very close to the item so that I can shoot at f/27 or higher without under-exposing the shot - this is using a Fuji S1 with a Nikkor 105mm macro lens, btw.

So not just digicam users want deep DOF ;). Although in the case of said digicam users, I think it's just about not knowing any better and not being schooled in 'creative use of focus', and things like that. They just assume, rather logically if you think about it, that you want the whole thing to be in focus :). After all, alot of people look at the impressionists and think 'this person must have had bad eyes.' Realism and photorealism are the grails of popular art.

I personally also like alot of control over DOF and depending on the subject, I can like it shallow or wide. This is obviously the improvement from tiny lens digicam to larger formats: more control.

.

Originally posted by paganini:

It's not a generalization -- i'd rather have more control over DOF (small increments of DOF) and sacrifice some great dof, versus not being able to do that.

You were arguing for greater DOF between 50 and 100 mm, that's true at a given distance 50 will have more, but iwth the same "MAGNIFICATION", it's the same and thus the point is moot.

Originally posted by magnetic9999:
The ability to have more DOF on a macro is very desirable - whether or not you use it on a particular shot - it's good to be able to have it for those times when you shoot REALLY small things and you want more than a razor thin region in focus. Your generalization about who or what likes what is merely that - an uninformed generalization :)

Originally posted by paganini:

(Only digicam users like infinite dof :) because it's really easy for them to get it)

Originally posted by magnetic9999:
yes. exactly. it (the 100mm) has shallower DOF. but who ever wanted less DOF on a macro? you always want more ;).

Originally posted by paganini:
Yes, but 50mm macro is only 0.50x life size unless you get the life-size converter. 100mm macro is 1.0x AND has shallower DOF. You basically get similar DOF shutting it down at F16 and adjusting the distances.

Slap on a 250D filter and the 100mm will be about 1.3x or 1.5x lifesize (forgot which one)!!!

Message edited by author 2003-04-18 16:37:46.

joshua

Canon EOS-500D Rebel T1i

Canon EF 50mm f/1.8 II

04/18/2003 04:33:09 PM · #33

we need a shallow dof challenge, for exactly these reasons...if your camera doesn't allow aperture changes, selectively smear the lens with grease until you get the desired effect

04/18/2003 04:49:28 PM · #34

Do you get dust problems shooting at F22 with a S1? Just wondering.

Yes, i think the digicam phenomenon has made people wanting to see the greatest DOF and sharpest flowers (overly sharpened) as possible. Maybe it's just me but I like flowers to be soft, not sharp, at least that's how I relates to flowers.

Well, i happen to like impressionistic photos :) at least things with interesting subjects in the background and the foreground blurred. Couldn't do that with the G2 very well, but the 10D with the telephoto lens works nicely :)

Originally posted by magnetic9999:

04/18/2003 04:59:13 PM · #35

Originally posted by paganini:

Do you get dust problems shooting at F22 with a S1? Just wondering.

Big time. Although I can get the sensor pretty clean and spot edit the rest that make it through.

Originally posted by paganini:

Well, i happen to like impressionistic photos :) at least things with interesting subjects in the background and the foreground blurred...

Me too. It's all about options . . .

04/18/2003 05:01:17 PM · #36

Is this one impressionistic enough for you or too sharp or too shallow DOF?

//forums.consumerreview.com/crforum?14@98.APJuaFfWtvc.1@.efc8ba9

I took this one with the 50mm macro, again because it is what I had on my person at the time.

Greg

04/18/2003 05:28:20 PM · #37

the DOF is great, for me.

Gordon

RIM BlackBerry Curve

Canon EF 85mm f/1.8 USM

04/18/2003 08:01:27 PM · #38

Originally posted by magnetic9999:

So not just digicam users want deep DOF ;). Although in the case of said digicam users, I think it's just about not knowing any better and not being schooled in 'creative use of focus', and things like that. They just assume, rather logically if you think about it, that you want the whole thing to be in focus :). After all, alot of people look at the impressionists and think 'this person must have had bad eyes.' Realism and photorealism are the grails of popular art.

I think the digicam issue is that DoF is also proportional to sensor size (bigger sensor, shallower DoF) Most prosumer digicams have pretty much infinite DoF and you have to work hard to get any significantly out of focus areas at all.

Compare that to a f1 lens on a medium format camera where you are lucky to get anything at all in focus wide open.

Ignorance also can lead to dislike. If all the shots you take have great DoF, might you take a blurry photograph as a sign of something wrong, after all, every shot you've taken is sharp ?

04/18/2003 10:17:42 PM · #39

Originally posted by Gordon:

I think it's as much people not using proper technique or wanting shallow DOF in prosumer cams...I took these as samples of the DOF available from the F717 that I bought on Thursday. They aren't macros...all with the subject at least 5-6 feet away (the girl more like 10) at 190mm equivalent, F2.4. These are straight out of camera, with only a resize and a compression of 10 on export. I don't see it 'sharpening the hell out of' anything, and the DOF is quite shallow and pleasant. Is this not acceptable? I'd like to hear your thoughts...

Brandi
Bluebells
Fence
Bluebells II

Message edited by author 2003-04-18 23:27:31.

04/19/2003 12:30:12 AM · #40

Those are some nice examples, but you still don't have the DOF control that you would with a DSLR. You have, however, demonstrated quite effectively that the 717 is capable of some fine low DOF performance.

Greg

04/19/2003 12:49:32 AM · #41

Thanks. This camera has definitely exceeded my expectations as far as image quality goes. It seems to get bashed a bit from the DSLR group as a camera that oversharpens everything, and has poor DOF control. I personally think that the images I'm getting out of that camera are of an equal or higher quality than some of the images from non-L lenses I've seen people post as examples from their D60s and 10Ds.

Sure, the DSLR is better, I'm not saying it isn't. But, I'd question the logic that you need to go that route in order to get some top-quality photographs.

Message edited by author 2003-04-19 00:54:47.

04/19/2003 01:50:22 AM · #42

I think that anyone saying that the 717 is not a decent camera is kidding themselves. The most important thing is of course that you are happy with it. I am sure you will get lots of really great pictures with it and will not regret buying it.

Greg

04/19/2003 02:57:52 AM · #43

L lenses are good but primes are just as good (some are better, the 50 mm F1.8II lens compared to a 24-70mm L lens @50mm will blow it away, for example). L lenses are going to be better than zoom lenses, where it really shines.

BTW, your photographs are nice but they are in macro mode, right? Try some of the shots without macro mode. The sample i posted in another thread (depth of focus) is NOT in macro mode and has extremely small DOF. The thing is that since the lenses are small to mate with the smaller sensor, the focus length for all of the prosumer/consumer cameras are small. The circle of confusion is thus small and therefore the depth of field is small. Here is a comparison of DOF @ 35 mm equivalent of 50 mm focal length @ F2.8:

Sony (13 mm focal length): 1.58 - 2.72 (focused at 2 meters)
D60 (31 mm focal length): 1.81 - 2.23 (focused at 2 meters)

Sony has about 1.14 meters of depth and D60 has 0.42 meters of depth, quite a big difference.

At "macro" focus distances say of 0.5 meters:
Sony: 0.47 - 0.53 m
D60: 0.49 - 0.51 m

This is where it makes a big difference -- D60 would have only 20 cm of depth, Sony would have over 60 cm of depth, 3 times as much. If we went with other lenses with lower F number, then there is obviously no question about it. The numbers are from www.dofmaster.com

DSLR simply gives you more options, that's all. heck, my G2 is pretty cool :) biggest problem? lens distortion @ wide angle. It actually is an awesome camera for macros with RAW file capability giving you the control you want post processing (i.e. straight from the sensor, similar to any DSLR) Am I going to sell the G2? Nope, there are plenty of uses for it left -- if you were going to trek for several nights of camping, would you want to carry all that DSLR stuff or just a G2? I'd just take the G2.

Originally posted by jimmythefish:

04/19/2003 03:16:17 AM · #44

Originally posted by paganini:

Nope, not in macro mode, as I explicitly said. They were at full telephoto (190mm equivalent) at an aperture of 2.4. Sure, the subjects were fairly close (10 feet for the portrait, 5 feet for the others).

James.

04/19/2003 03:24:44 AM · #45

I totally agree with you as far as the numbers go, but I'm a bit concerned that people here are being advised and/or feel they need to buy a DSLR just to get any DOF control at all. Not many people on this site who own fixed lens cameras even know to use the widest aperture at full telephoto for portraits, for example. Knowing how to get the most out of a camera certainly helps in using the camera in question!

Well, I'm jealous of you guys anyhow ;).

James.

Gordon

RIM BlackBerry Curve

Canon EF 85mm f/1.8 USM

04/19/2003 09:39:42 AM · #46

What I found interesting when I moved from the G2 to the D60 was that, yes I could get some level of shallow DoF in the G2 but I really had to work at it. Your fine 717 examples show the kind of DoF that the G2 provides, although probably better due to the better telephoto on the 717.

The thing is, I had to really try to get any shallow DoF with the G2. In contrast I found that at first I was fighting with the D60 to get enough DoF. Pictures that I'd expect to have tons of sharp details tapered off pretty quickly, because I'd been used to the much much wider DoF with a small sensor camera - and that is mainly the issue - available DoF is inversely proportional to sensor size, so it is harder to control DoF, the smaller the sensor is.

04/19/2003 10:32:34 AM · #47

the DOF isnt about the sensor size - directly, although it is an 'epiphenomenon' of it. It's about the size (focal length) of the glass fitted to the camera. Because these cameras can get 35 mm equivalent field's of view with much smaller glass (which *is* because of their tiny sensors), their DOF is much deeper. For example, my E-10 uses a 9-36 mm lens to give 35-140mm equivalent results.

However, if you take a given 35mm lens and test it first on a camera with a smaller sensor (ie 10D or D60), and then put it on a film camera or a 1Ds (full frame) and shoot, although your field of view will be different because of the sensor crop, the pics will have the same degree of DOF. Because again, it's directly dependent on the glass, not the sensor size.

All that said, here's an example of 'shallow' DOF from my E-10:

Of course I had to maximize the factors that lead to this - get close to the subject, zoom in, and make sure the bg is relatively distant. I.e. use relatively extreme settings to achieve something that is alot easier with a DSLR. Of course, since I was using my widest aperture, I was frequently bumping into my max shutter speed, when trying to get narrow DOF outside.

As Jimmy says, knowing how to get the most out of your camera is really the key. But at the same time, because there is a 4 to 5 f/stop difference between DOF at a given aperture, it takes a while, after getting a DSLR, to realize that I need to use f/16 and stuff to get deep enough DOF in some situations -- because my old camera only even went up to f/11!

Sorry for rambling .. :)

04/19/2003 11:40:39 AM · #48

The nice thing about the world is that you can often break things down into math. This from this photo.net article which I found quite interesting.

Here F is the focal length. D is the subject distance, c is the circle of confusion and fn is the f# (f-stop) of the lens. Now this equation doesn't reduce to some simple rule of thumb. However we can say that over the range of focus distances which aren't in the macro range (where D is close to F) and which aren't close to the hyperfocal distance (where D = F*F/fn*c) you can "guesstimate" that the depth of field ratio between two lenses used at the same aperture and focused at the same distance by assuming it's proportional to the size of the circle of confusion and inversely proportional to the square of the focal length.

Again, this simple analysis only applies at "intermediate" distances, but we have to have that limitation if we want a "simple" formula. It only really breaks down when the lens is focused further than about halfway to the hyperfocal distance or when we get to magnifications near 1:1

Now I think we all know that to get the same field of view on different format cameras we need different focal length lenses. Most people by now know that the EOS 10D has a 1.6x "multiplier", meaning that a lens designed for use on a 35mm film camera when used on an EOS 10D gives you the same field of view as a lens 1.6x longer on a conventional full frame 35mm camera. So a 50mm lens when mounted on a 10D gives you the same field of view as you would get with a (50x1.6) = 80mm lens on a 35mm film body.

So the bottom line - and all you really need to know - is that DOF is inversely proportional to format size. Note that format size is inversely proportional to the "digital multiplier". The higher the "digital multiplier", the smaller the format and thus the greater the depth of field. Note also that now you can see one of the reasons large format camera users need tilts and swings to get adequate depth of field. With an 8x10 camera you have about 8.5 times LESS depth of field than you do with 35mm for the same image. This also explains why consumer digicams, some of which have sensors 1/6 the size of 35mm film, have such a large depth of field and one of the reasons why it's almost impossible to get blurred backgrounds when using them.

Message edited by author 2003-04-19 11:47:06.

04/19/2003 11:47:49 AM · #49

Actually it is, as circle of confusion is directly related to the size of the sensor versus a print 8x12 in size. Don't have the equation with me but basically the diagonal length of the FORMAT divided by a constant. And CoC is directly related to DOF as well.

I think one thing that is confusing to people is that they don't realize that the goal for DOF calculation is for a 8x12 print. If you print larger, the DOF will be different :)

A link to the equation:

DOF Equations
[quote=magnetic9999]the DOF isnt about the sensor size - directly, although it is an 'epiphenomenon' of it. It's about the size (focal length) of the glass fitted to the camera. Because these cameras can get 35 mm equivalent field's of view with much smaller glass (which *is* because of their tiny sensors), their DOF is much deeper. For example, my E-10 uses a 9-36 mm lens to give 35-140mm equivalent results.

/quote

Message edited by author 2003-04-19 11:52:43.