What Zeiss ZF lenses would you like to see?

[frank_skomial]

Eric is wrong, and Ilkka is right.

 

Eric posted a link to Metha (or somethink) and assumed that was true what Mr. Metha "brags about", where fact is that the author does not know what he is talking about, e.g: "The new Speedlight SB-800 introduces a number of refinements to D-TTL flash performance technologies, Nikon term i-TTL" - an expression of total ignorance.

 

iTTL is totally departed form D-TTL technology, that is, the distance is determined during preflashes and not by D lens providing distance information. That is what makes the new wonderful technology (CLS/iTTL) work so great.

 

If lens D distance was used, only flash on the camera would be possible to utilize that information, and not any other lens in the iTTL multiple flashes setup, where the D-lens information is practically useless.

 

In my multiple flash iTTL(CSL) setup, I never use any flash mounted on the camera.

 

Eric, give it up, and admit Ilkka is correct.

[eric friedemann]

"(With) iTTL ... distance is determined during preflashes and not by D lens providing distance information."

 

 

Did what you wrote make sense to you? Do you think monitor preflashes are the same as radar?

 

 

With i-TTL flashes, as with earlier flashes that used preflashes, monitor preflashes provide the camera/flash with information on how reflective the subject is. Preflashes do not provide the flash/camera with distance information.

 

 

The only way the flash/camera can know distance information is when a D-compatible lens tells the flash/camera how far away the subject is by focus. Allowing the flash/camera to know the distance to the subject is the most important piece of information that can be provided for accurate flash exposure. Preflashes alone can skew flash exposures where subjects are very dark or very light.

[joel_hammers]

Here's an example of i-ttl in action. D70 with pop up flash in commander mode, SB-600 off camera to the right, 85mm f/2 AIS (not af or afd). Eric, you are 100% wrong. I-ttl works fine without the d info.

[frank_skomial]

""(With) iTTL ... distance is determined during preflashes and not by D lens providing distance information." " - what I really mean that distance does not matter at all in iTTL, but the amount of light is determinmed during preflashes (not exactly the distance but the amount of light needed as the distance does not matter at all)

 

Distance only matters for focusing and is used to Auto focus of the lens and for NOTHING else in the iTTL mode. For all iTTL flashes, the amount of light each flash produces is determined during pre-flashes.

 

Eric, how many people need to tell you that you are wrong?

[frank_skomial]

"Do you think monitor preflashes are the same as radar? "

 

- the light is not a radar, but the effect of it is an equivalent to a radar action, and that is an appropriate to distance, (and other factors/reflectivity), apprioriate amount of light is determined, even though the distance as such may no be used, just the reflected light intensity.

 

Remote flash emits a minimal TEST value amount of light during preflash, sufficient to determine required amount of light during exposure time. The TEST value is small, since the rest of energy must be preserved for the actual exposure flash that will happen within small fraction of a second.

 

Eric, seems that you are still living in the older D-TTL world, and not in the iTTL world, since are saying: "The only way the flash/camera can know distance information is when a D-compatible lens tells the flash/camera how far away the subject is by focus. Allowing the flash/camera to know the distance to the subject is the most important piece of information that can be provided for accurate flash exposure." -

 

There were reported focus problems with Spot metering, taking pictures of 2 people, and the focus was set at the very distant background behind the people, (so the D-lens distance was way too far), but the flash exposure was correct, and that means determined by preflash - and NOT by the lens distance, in that was in the iTTL flash mode.

 

In iTTL the flash does not have to know the distance from the lens to subject, as it only cares abouth the distance between the flash and the subject, and that usually is different for flashes not mounted on the camera, and that is the major advantage of the iTTL as the flash will not fail if you set wrong focus (D-lens info wrong). Even with flash mounted on camera, in iTTL mode only, the flash does not care about the lens distance, as it will need to make own determination of the required light. Flash will produce correct output even if the lens is totally out of focus and showing incorrent distance value on the lens.

 

Look a bit differently, when there is no flash on camera at all, how then the lens distance to object matters for a flash that is located far away from the camera, and at difference distance than the cammera?

 

You say "Preflashes alone can skew flash exposures where subjects are very dark or very light" - that does not happen, as the flash is mmuch smarter than you give it little credit. The CLS system is not perfect, but is much better than D-TTL, or any other automated mode.

 

Perhaps you do not use the iTTL mode ?

[eric friedemann]

"Eric, how many people need to tell you that you are wrong?"

 

 

One person who knows what they're talking about would be sufficient. Look, if you want to pay top dollar for German lenses manufactured over 5,000 miles from Germany with an antiquated AI lens mount from the 1970s, tell yourself what you have to to justify the price.

 

 

I've now shot with every generation of Nikon flash. THE breakthrough technology in flash photography was D lenses. Telling an automated flash system the distance to the subject allows the precision of manual guide number shooting. The preflash adds a belt to a pair of suspenders and is an unfortunate novelty that can be fooled by light or dark subjects.

[ilkka_nissila]

1. Eric, the "D" info as provided by the lens is insufficiently accurate to be used as sole determinator of flash exposure. That's why preflashes are needed to determine how much light is needed to obtain a good exposure. The SB-800 has a Guide Number mode, which curiously requires you to manually give the distance from flash to subject. No possibility of asking the lens. Guess why? Because the lens info is inadequate.

 

2. The GN of a flash varies over its lifetime.

 

3. The exposure given by the "guide number rule" works by assuming standardized surroundings, e.g. a white room of a certain size, or similar overall reflectance and size.

[joel_hammers]

Let it go Eric.

[eric friedemann]

"Let it go Eric."

 

 

Joel, allow me one more bite at the apple; then I'll let it go.

 

 

"(T)he 'D' info as provided by the lens is insufficiently accurate to be used as sole determinator of flash exposure."

 

 

This is the first time I've read that D lenses do not pass accurate distance information to flashes. The statement also contradicts what I've been told by two Nikon field technical reps and a discussion I had in the late 1990s with John Clouse, who is now Senior Vice President of Nikon's Photo Sales Division. However, if you are aware of any published data, I'd like to read it.

 

 

"The GN of a flash varies over its lifetime."

 

 

Understanding that I've never shot a flash long enough for its tube to yellow, the many Nikon flashes I've owned have given constant and accurate manual output- when necessary- over a period of years. Certainly, Nikon wouldn't have introduced an admitedly primative guide number mode with the SB-800 and compatible cameras if the company wasn't convinced of the long-term consistency of its flashes' output.

 

 

"The exposure given by the 'guide number rule' works by assuming standardized surroundings, e.g. a white room of a certain size, or similar overall reflectance and size."

 

 

I don't know what a "guide number rule" is. Googleing the term, I get nine odd posts, none of which support your statement.

 

 

The guide number of the flash relates to the amount of light it will produce. Guide number equations [i.e. Guide number (GN) = F-stop x Flash-to-subject distance] do not reference surroundings.

 

 

Ilkka, I'll give you your due. If Nikon was not worried about sample variation in its flash, body and/or lens circuitry, or some other variable, a pure guide number mode could have been introduced with the advent of D lenses. With D lenses, the camera/flash should know all the necessary variables to produce THE correct direct flash exposure- subject distance, ISO, f/stop and the flash's potential power.

 

 

That having been said, over tens of thousands of TTL flash exposures I've taken without and then with D lenses, I've noticed a pronounced improvement in exposure accuracy with D-compatible lenses. This is particularly true when shooting subjects that would have fooled earlier TTL flash systems (i.e. bride in white dress, groom in black tux).

 

 

I have also seen a dramatic improvement with D lenses in shooting close subjects (1-4 feet) at shallow apertures (f/5.6 or wider). Such exposures routinely resulted in overexposure with earlier TTL systems.

 

 

As such, I'm simply uninterested in 35mm-stlye cameras and lenses that don't provide the camera with distance information. But then, in a given year, I probably take more photos with TTL flash exposure than without.

[eric friedemann]

"You're more concerned with correct exposure in flash photography than ultimate image quality."

 

 

Steve, as I noted earlier I think its questionable whether you will actually see any difference whatsoever in "ultimate image quality" with the ZF lenses. Understanding that a ZF lens might fare a little better- or a little worse- than a similar Contax lens, Photodo has done reasonably objective MTF testing on the Contax Zeiss Planar 50mm f/1.4 35mm SLR lens and the 50mm f/1.4 AFD Nikkor:

 

 

"Contax Planar T* 50/1,4- Weighted MTF for 50 mm: f1,4 0,57, f2 0,69, f2,8 0,80, f4 0,85, f8 0,86; Weighted MTF 10 lp/mm: 0,92, Weighted MTF 20 lp/mm: 0,83, Weighted MTF 40 lp/mm: 0,66

 

 

Nikkor AF 50/1,4D- Weighted MTF for 50 mm: f1,4 0,56, f2 0,68, f2,8 0,75, f4 0,80, f8 0,85; Weighted MTF 10 lp/mm: 0,91, Weighted MTF 20 lp/mm: 0,80, Weighted MTF 40 lp/mm: 0,59"

 

 

A-Bing the numbers, the lenses are quite comparable. I would be surprised if you could tell machine prints from the two lenses apart at any size. Based on the scores at 40 lp/mm, you might be able to see a slight difference in very-well-executed 11-inch or larger prints.

 

 

"Believe me, TTL of any sort is a huge improvement over automatic or manual flash."

 

 

Having shot F3-variants and an FE2 with Nikon flashes from the time the products were introduced, I found the first generation TTL provided a very modest improvement in exposure accuracy over the thyristor Vivitar 283s, 285s and 365 I shot from the late 1970s through the early 1980s. The improvement was least noticeable with off-center subjects, very light subjects, very dark subjects and very close subjects.

 

 

I don't mind that you don't like the formal simplicity of my event images- though the guy in the little sombrero was shot in a nearly pitch-black room. I hope you don't mind my saying that I find flash-and-jiggle ... let's just say the last time I made images like that was at college parties- and I was drunk. Also, had you used bounce flash, the available light shot could have had adequately-exposed flesh tones. I would worry that if I loosened up to shoot images like those, my customers might conclude that I didn't know how to properly compose and expose images. ;>)

 

 

However, I understand the arty fad wedding photography is going through and our respective event clients are apparently looking for different qualities in their images. So, we'll set aside that we don't like each other's event shooting. We'll ... live and let live.

 

 

Again, the vast majority of photographers I sell Nikon equipment to will benefit from D lenses in their flash photography. Having owned Zeiss lenses for Hasselblads and Contax G cameras, I respect the lenses, but am not overawed by them. Having owned Leica M and R cameras, I have a similar respect- not reverence- for Leica lenses.

 

 

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00FP4A

[ilkka_nissila]

My main concern with some of the Nikon AF-D lenses is not their optical quality but the mechanical quality. Manual focusing is difficult at best with a wobbling lens barrel and uneven dampening. This drives me nuts and makes it very difficult to follow a moving child with a 50/1.4 or f/1.8 AF-D while it's very easy using a 105/2 AF-D DC Nikkor.

 

If the Zeiss lens is essentially the same as Ai-S Nikkor in terms of optics, either will do. However, it seems obvious that the Ai-S Nikkors are on their way out as a lens line so the ZF lenses fill the void for those of us who prefer manual focusing ease to metering features.

 

As to the GN stuff, the guide number rule specifies that with iso 100 film, you get correct exposure using an aperture of GN/distance. This assumes certain reflectance properties for the surroundings. When you flash your flash, some of the light hits the room walls, floor and roof, and is scattered to various directions, and some of the light will hit the subject. If you assume the GN rule is exact and set the aperture accordingly (with no available light), you should get an underexposed subject if you shoot outdoors. If you shoot indoors in a very small white room, you'll get overexposure. The Guide Number and distance only give a rough idea of which aperture gives the correct exposure at full power of the flash.

 

I have to admit I don't have a reference for the lack of precision of the D info. I read it somewhere on the internet that the actual information is only something like 6 distinct values, or in that ball park. If this info is true (I could not find where I read it), it is not sufficient to determine flash exposure using the guide number principle. So preflashes are used. (Also because of my other points.) Now, it could be that the distance info is indeed precise, and the web source I read was wrong or just speculating. I don't know. However, the fact that the SB-800 has a GN priority mode which does not use the D info from the lens but requires a manual input of the distance basically hints in the direction that the source is correct. Why would Nikon require the user to give the distance when it's supposed to receive that info directly from the lens? Or is it assumed that the lens is off-camera? That doesn't make sense as usually people use flash meters when the camera is far from the flash.

 

In any case, the D info and CPU are optional for the operation of the i-TTL/CLS flash system so D200 users should be able to do flash work quite well with manual focus lenses. When Zeiss comes out with a moderate wide angle for the ZF mount, I may buy it and report how my D200 flashes with it. I don't have a non-D and non-G lens with me right now although I do own a couple.

[ilkka_nissila]

In answer to the original question, I would like to see 28/2, 21/2.8 or 21/2 and 35/2 in addition to the 50/1.4 which we know is coming. Also, if possible, a DX format 14/2.8 or 14/4.

[ShunCheung]

Folks, the debate here has gotten quite off topic and repetitive. Please give it a rest.

 

I'd also like to remind everybody again that attached images in line should follow the photo.net guidelines: within 511 pixels across and 100K bytes in terms of file size. I am quite sick of cleaning up over-sized images. If your post gets deleted for that reason, please feel free to repost but with image sizes within the guildlines.

[joel_hammers]

Eric, please explain to me then how a D70 can come up with a correct ttl flash exposure with an off camera flash with a little diffusion on it placed at a different distance away from the subject using a lens that has absolutely no means of communicating f/stop or distance information to the camera. ITTL is sweat!

I will admit using AIS lenses with a D70 is not the best since there's no way to meter ambient light with it. The flash exposure with iTTL works perfectly though...as well as with my AFS lenses. I have to take a couple of test shots to balance the ambient light controlling that with the shutter speed. It's really not rocket science to do that but it isn't the best. This is one big reason I want a D200. It will work so much better with my MF glass that I love and am not planning on getting rid of. It has a big, juice viewfinder to make focusing easier. I think there is a decent market for these new Zeiss lenses. I'm quite happy with my MF nikkors and probably won't buy a Zeiss but I'm sure quite a few people will and good for them! Now Iﾒm waiting for someone to tell us how the MF lenses are not fully compatible with the d200, d2x, or f6. You are right but if you look at it from the other side, those cameras with the features that they have, especially iTTL, are arguably the most capable manual focus cameras Nikon has ever made. No, AIS lenses can not take advantage of every feature the camera has to offer but a MF lens on these cameras can do a whole lot more than a MF lens on my F3.

[keirst]

Good, Eric, we'll agree to disagree. I also shot some formal photos at the handful of

weddings I've shot for friends. I just would not say there's anything special about those.

I'm sure the families value both kinds, but I don't. Whatever works for you is fine, it

doesn't affect me after all. By the way, he worst wedding photo's I've been associated with

were ones I printed shot by another photographer, with a Hasselblad and Zeiss lenses.

Many were poorly exposed and the negatives cut into single frames. They were so dirty I

had to hand wash every one my friend wanted printed.

 

I don't reverence any particular lens or camera company. Nikon, Zeiss and Leica have all

made good and bad products. I like a lot of the Nikkor Teles I have, and even sprung for

an AF-S 300mm/4 and AF-D 85mm/1.4 recently. But I haven't liked any of the AF

wideangle primes I've owned. None were very good wide open. I regret most trading my

28mm/2.8 AIs Nikkor for the 28mm/2.8 AF lens. If Zeiss cones out with a lens that is

better than the 28mm/2.8 AIs, I'll trade a couple Leica lenses I don't like for it (90mm

Apo-Summicron and 21mm/3.4 Super Angulon). If not I'll just buy a used AIs 28mm.

[keirst]

Shun, I did not realize the picture size limit also applied to off-site images. My two images

above are being linked from our webserver at Harvard, and take up no space on Photo.net

(other than the html image source link). But I'll resize next time.

[ilkka_nissila]

The 28/2.8 AF is an infamous lens, you did indeed do a bad trade. You can still buy the 28/2.8 Ai-S even new. Regrettably, the 28/2 is no longer included in the list of manufactured lenses, although it can still be mail-ordered new in some places.

[eric friedemann]

As to Nikon 28mms, I've owned or used at least one of every model from the first AI forward. I've been wowed by my current 28mm f/1.4 AFD. It is reasonably sharp wide open, but it really shines from f/2.8-4.0, two to three stops off maximum aperture.

 

 

The bokeh of the lens is pretty good, but it is an ASPH lens. So, out-of-focus point light sources look a little odd.

 

 

That the lens has been discontinued is not surprising given the 28mm f/1.4's price and that the lens is a 42mm on Nikon DSLRs, which now dominate the Nikon line. It was quite dissapointing that Nikon didn't introduce a fast 18mm or 19mm DX prime lens at PMA.

[keirst]

<a href="http://www.photo.net/frequent-questions#upload_forum_images"> http://

www.photo.net/frequent-questions#upload_forum_images</a> does not specify a size

limit on "img" tag images, linked to another server. It says "If you use this approach,

please be polite to other forum readers, and do not embed very large images in your

posts..." A vague guideline should be interpreted in favor of a poster, especially since no

one was hurt and no server space on Photo.net wasted.

So I'm a bit miffed my post above was deleted, text and images both. I'm not retyping the

thing.<br><br>

If you care to see the only two wedding photos that I took that I actually like, see <br><a

href="http://www.people.fas.harvard.edu/~keirst/friends/friends2.html">http://

www.people.fas.harvard.edu/~keirst/friends/friends2.html</a> <br>and <br><a

href="http://www.people.fas.harvard.edu/~keirst/friends/friends3.html">http://

www.people.fas.harvard.edu/~keirst/friends/friends3.html</a><br>for the large

(warning: 800 pixel wide!) images. Both shot with F4, 24mm/2 AIs Nikkor, first with

available light second with TTL flash via SB-26. The second was published in Diversion

magazine, a journal of what physicians do in their free time, in an article on Dr. Lisa

Adams.<br><br> Good night.

[ShunCheung]

Steven, almost weekly we are reminding people in this forum to limit the size of their images. I happened to be away from home during the day and was using a public computer. Your two 200K images got stuck half way during the download and 800 pixels across is very annoying.

 

I was editing everybody's over-sized post and it has reached a point that I'll just keep deleting those posts until people comply.

 

Your original post was included in the delete e-mail notification so that you can easily cut and paste your post back here (assuming you received that e-mail), if you choose to.