Are xpan negs MF quality?

[Wiyum]

-You have responded that the xpan takes images that are the same as 2 35mm's stitched together. This suggests that MF lenses are designed in the same manner as 35mm lenses(which we know they are not) Some have even suggested that they have a large 'sweet spot'...

Basically I am asking if the xpan print will look like a strip out of the center of a 6x7(with all the tonality of MF)...

Is tonality partly a function of MF lenses?

I know, the term 'tonality' is very subjective, but I hope my response will better describe what I mean. The x-pan looks like an excellent camera to me. If it can give me the tonality I want on a 35mm format , I will be happy. 🙂

Lincoln,

You bring up a good point, and you reveal that I did in fact misstate the facts earlier. An X-Pan print will not look exactly like two 35mm negatives stitched. Here's why.

You're right in stating that 35mm lenses and medium format lenses are not designed in the same way, but also quite wrong. All lenses are designed with a certain format in mind, and all lenses "draw" a projection that is a circle. Because one doesn't typically find circular formats, the rectangle of the format is inscribed within the image circle of the lens' projection. In a perfect world, there would be a uniformity of image quality within that rectangle, but this is rarely, if ever, the case. Lens design is a science of compromises, and the edge of that image circle always involves a falloff of both exposure and resolution. Unfortunately, the corners of a format often fall into this falloff area, and as a result there is a quality loss in the corners. This loss is typically slight in real-world use, but you can't enter an internet photography forum without finding people arguing about the soft corners of lens X or the irrefutable corner performance of lens Y. Regardless, there is usually a point where the image circle is falling off contained within the corners of the format rectangle.

For this reason, two stitched 35mm negatives would have corner falloff at the seam that wouldn't exist in the X-Pan print.

Medium format lenses quite certainly have larger sweet-spots, but that is only because there is a larger negative to cover. Viewed as a proportion of the negative that falls within the sweet spot, my guess, untested, is that you're looking at a similar percentage, and one that varies not only manufacturer to manufacturer, but also specific lens to specific lens.

The lenses for a 35mm camera should draw a circle with a minimum diameter of 43.27mm. The lenses for the X-Pan should draw a circle with a minimum diameter of 69.28mm. The lenses for a 6x7 camera should draw a circle with a minimum diameter of 86.04mm. These are again minimums, but they are the diagonal measure of the format rectangles. Lenses will always project a circle with a larger diameter, but the falloff will still creep in a bit.

For this reason, the cropped 6x7 negative would perhaps be slightly sharper than an X-Pan negative, assuming a center crop, because the corners of the resulting print aren't really going too close to the edge of that 86mm circle.

Notice, though, that I said sharpness. That's because sweet-spots pertain to resolution, sharpness, and exposure falloffs. MTF charts describe exactly this phenomenon, usually measured in line-pairs per mm, from the center of the image circle to the corner of the frame (the most extreme part of the circle being used).

Perhaps this is pertinent to your quest for tonality, and perhaps not. When I discuss tonality, I'm typically using it to describe differences in film stocks, and not formats or lens manufacturers. Regardless, I hope this is helpful in explaining what "medium-formatness" you could reasonably expect from the X-Pan.

Will

 

[Wiyum]

Here's a visual representation of what I described before. The red circle is the minimum image circle for 6x7, the green circle is the minimum image circle for X-Pan, the blue rectangle is the format rectangle for 6x7, and the black rectangle is the format rectangle for the X-Pan.

As you can see, that center crop of the 6x7 negative isn't going anywhere near the edge of the image circle for those lenses.

Will

 

[Lincoln]

Lincoln,

You bring up a good point, and you reveal that I did in fact misstate the facts earlier. An X-Pan print will not look exactly like two 35mm negatives stitched. Here's why.

You're right in stating that 35mm lenses and medium format lenses are not designed in the same way, but also quite wrong. All lenses are designed with a certain format in mind, and all lenses "draw" a projection that is a circle. Because one doesn't typically find circular formats, the rectangle of the format is inscribed within the image circle of the lens' projection. In a perfect world, there would be a uniformity of image quality within that rectangle, but this is rarely, if ever, the case. Lens design is a science of compromises, and the edge of that image circle always involves a falloff of both exposure and resolution. Unfortunately, the corners of a format often fall into this falloff area, and as a result there is a quality loss in the corners. This loss is typically slight in real-world use, but you can't enter an internet photography forum without finding people arguing about the soft corners of lens X or the irrefutable corner performance of lens Y. Regardless, there is usually a point where the image circle is falling off contained within the corners of the format rectangle.

For this reason, two stitched 35mm negatives would have corner falloff at the seam that wouldn't exist in the X-Pan print.


Will, I fully understand the principals of light falloff, but I appreciate your chart and taking time to accurately describe the effect. This effect of light falloff is certainly relative to tonality, but I'm not sure how. The suggested capture for images destined for stitching is to overlap images by 1/3 or 1/4. This is mainly to overcome distortion in the stitching process. It must also go some distance in mitigating the falloff effect at the stitched seams.

Some posters have suggested that tonality is purely a matter of 'real estate' ie, the more neg there is, the more tonality you will get. If tonality is *not* a function of MF lenses then I should be able to test this effect with my 35mm Contax G2. I am going to try to stitch together several images shot with my 90mm lens. Hopefully, I can compare this stitched image with a single exposure taken with my 28 mm. If I am successful with this test, I will be able to compare apples to apples. Or at least, a long stitched image will giive me more 'real estate' for the same view area.

Thanks for your thoughtful input, you've gotten me thinking hard on the subject. 🙂

Lincoln

 

[Kawabatnam]

Xpan + Scan quality w/ Epson 4490?

Xpan + Scan quality w/ Epson 4490?

Here's a visual representation of what I described before. The red circle is the minimum image circle for 6x7, the green circle is the minimum image circle for X-Pan, the blue rectangle is the format rectangle for 6x7, and the black rectangle is the format rectangle for the X-Pan.

As you can see, that center crop of the 6x7 negative isn't going anywhere near the edge of the image circle for those lenses.

Will

Hello, I am considering a Xpan camera and wouldl scan the negatives with the Epson 4490. Since I get poor results while scanning 35mm negatives but quite good ones (in comparison) with MF negatives (actually 6x4.5 negatives from a Fuji ga645) I am wondering what to expect from the Xpan...
I understand the Xpan has a dual format capacity, panoramic format and standard 35mm format. What I don't understand is this: when shooting the same subject matter in each format (same lens of course), what do we get?

1) Is the 35mm format a "crop" from the panoramic format, with both sides cut? If this is the case, then the panoramic scan should result (with my particular scanner) just as poor as any 35mm format since for instance adding information to the left and the right sides won't improve the final scan quality.

2) Or does the panoramic format show more or less an "Xpanded" view of what is covered by the 35mm format (= not adding information to both sides of the 35mm format, but "drawing" about the same information on a wider piece of film)? In that latter case, scan quality should be comparable to what I already get with 6x4.5 negatives.

Sorry if all the above seems a bit basic, but I have no experience with the Xpan and hope that option 2) is correct...
Thanks for any information.

 

[Kawabatnam]

Sorry to insist, but really no Xpan user to answer my previous post?

 

[sienarot]

If I understand the question correctly, I'd say #1, because it's just the frame mask that changes size. #2 sounds like that'd be accomplished by changing focal lengths.

 

[markuspd]

SWC and 35mm film?.

SWC and 35mm film?.

After using hasselblads for years and really never looking into xpans I am now in the market for one.
After reading though about the need for the centre filter and the use of a tripod due to the long speeds needed on many occasions I am now going off the idea.
Wondering has anyone tried using 35mm film in a hasselblad magazine?.
My idea is to use my SWC and a voigtlander finder which I can turn sideways which may allow for the use of 35mm film with a bit of a mask on the finder?.
What do you people think possible, worth the effort?, I can see no reason why it would not be great pano alternative.

 

[arturo]

After reading though about the need for the centre filter and the use of a tripod due to the long speeds needed on many occasions I am now going off the idea.
quote]

It is all a question of compromises. A SWC has a 38mm f4.5 lens, an XPan has either 45mm f4 or 30mm f5.6. The 45mm is slighlty less wide and slightly faster (without filter) or slightly slower (with filter). MY experience about the need for centre filter is this: if you shoot B&W or negative film you can pass without it, if you shoot slide you do need it. I believe the situations in which you need tripod are basically the same with a SWC or with an Xpan/45. The 30mm lens is a completely different beast, is much slower but also much wider.

In general, this thread seems to be about whether an Xpan delivers MF image quality. I think the question is wrongly posed. The Xpan delivers the same as a cropped MF. Full stop. The lenses are MF, the film is 35mm. The camera size is something in between. You can scan the film as if it was MF (with a flat scanner) or as 35mm (with a 35mm film scanner and stitching pictures). Everywhere I read that the latter is better.

I think people that approach this camera as a pocketable MF tend to be deceived. The point of this camera is the panoramic view. There is no free lunch, from a smaller camera you get smaller film size and you must limit print size.

 

[rxmd]

I understand the Xpan has a dual format capacity, panoramic format and standard 35mm format. What I don't understand is this: when shooting the same subject matter in each format (same lens of course), what do we get?

1) Is the 35mm format a "crop" from the panoramic format, with both sides cut? If this is the case, then the panoramic scan should result (with my particular scanner) just as poor as any 35mm format since for instance adding information to the left and the right sides won't improve the final scan quality.

2) Or does the panoramic format show more or less an "Xpanded" view of what is covered by the 35mm format (= not adding information to both sides of the 35mm format, but "drawing" about the same information on a wider piece of film)? In that latter case, scan quality should be comparable to what I already get with 6x4.5 negatives.

Sorry if all the above seems a bit basic, but I have no experience with the Xpan and hope that option 2) is correct...

Unfortunately option 1) is correct.

If option 2) were correct, the camera would have to switch the lens to an anamorphotic projection that projects images wider than they are tall. This would make no sense: (a) the lens would otherwise remain the same, so the quality of the anamorphotic picture wouldn't be better even though the projected image is bigger, and (b) in the final print one would have to correct everything back so there would be no point.

The XPan is a panoramic camera. If you're not interested in the panoramic image format, there is no point in getting an XPan. Get a better scanner instead, it costs less and you get more out of it.

Philipp

 

[markuspd]

After reading though about the need for the centre filter and the use of a tripod due to the long speeds needed on many occasions I am now going off the idea.
quote]

It is all a question of compromises. A SWC has a 38mm f4.5 lens, an XPan has either 45mm f4 or 30mm f5.6. The 45mm is slighlty less wide and slightly faster (without filter) or slightly slower (with filter). MY experience about the need for centre filter is this: if you shoot B&W or negative film you can pass without it, if you shoot slide you do need it. I believe the situations in which you need tripod are basically the same with a SWC or with an Xpan/45. The 30mm lens is a completely different beast, is much slower but also much wider.

In general, this thread seems to be about whether an Xpan delivers MF image quality. I think the question is wrongly posed. The Xpan delivers the same as a cropped MF. Full stop. The lenses are MF, the film is 35mm. The camera size is something in between. You can scan the film as if it was MF (with a flat scanner) or as 35mm (with a 35mm film scanner and stitching pictures). Everywhere I read that the latter is better.

I think people that approach this camera as a pocketable MF tend to be deceived. The point of this camera is the panoramic view. There is no free lunch, from a smaller camera you get smaller film size and you must limit print size.

I guess you are right, I am getting an xpan anyhow, just wondered if anyone tried this with a hasselblad.
Cameras and lenses have really not come very far as you would expect, still very limited considering how damn great they were were 50 years ago!, in fact the technology may have gone backwards!.:bang:

 

[rxmd]

Cameras and lenses have really not come very far as you would expect, still very limited considering how damn great they were were 50 years ago!, in fact the technology may have gone backwards!.:bang:

It hasn't gone backwards; only the direction how it has gone forward is not what some people would like. As much as I would like a compact 30/f2 Biogon for medium format, the reason why such a beast doesn't exist is not a lack of progress, but the laws of optics, which unfortunately imply speed limits for wideangles with large image circles. Etc. pp.

For how to run 35mm through a Hasselblad back, take a look at http://www.kievaholic.com/panoramic.html - it's a Kiev site admittedly, but it's 100% applicable to the Hasselblad A12 back.

If a Hasselblad SWC does it for you because it is wide and moderately fast, fine. The XPan gives you little amenities such as interchangeable lenses, a rangefinder, light metering, a wider negative, switchable image formats on one roll, and motoric film transport. If that's not what you're interested in, the XPan is obviously not for you, but there is certainly no reason to say that technology has gone backwards.

Philipp

 

[markuspd]

Hi thanks for the link that is great, some really good ideas there especially the foam!.
I love xpans and the is no way I am not getting one after seeing the images it makes.
But for your reasons to use it I am not so sure the choice of interchangable elnses is a major plus, just do what ansell adams, said take a few steps back and wallah wideangle!, I mean there are only three lenses here anyhow.
Motorised film transport yes good but really necessary, not at all.
A wider neg, is it?, wider than 6cm.
A light meter, I rarely use the one in a camera anyhow.
Switchable image formats well I can have lots of different backs on my superwide.
Rangefinder yes that is a plus over the SWC for sure, I like to be able to focus spot on ttl.
I did a test yesterday with an acute matte D screen the latest plain with split image against a bright screen in an old 500C (1959) and there is little if any difference!, I was amazed.
I don`t think photography has moved forward at all, not a bit.
Anyhow I still want an xpan, why?, its size, its a rangefinder and of course it s a pano.

 

[rxmd]

I am not so sure the choice of interchangable elnses is a major plus, just do what ansell adams, said take a few steps back and wallah wideangle!

Ansel Adams is wrong - and you yourself are the proof. Why do you bother with an SWC? Just take a plain old 503 with an 80/2.8 or a 110/2 and take a couple of steps back. Lens are a couple of stops faster, you get spot-on TTL focusing, and with the 80/2.8 it's also a whole lot cheaper.

But then Ansel Adams is overrated anyway. 😛

A wider neg, is it?, wider than 6cm.

65mm.

A light meter, I rarely use the one in a camera anyhow.

To each his own.

Switchable image formats well I can have lots of different backs on my superwide.

Well those two are technically solutions to orthogonal problems, since Hasselblad backs won't allow you to shoot 6x6 and 6x17 on the same roll, while the XPan won't allow you to change between films mid-roll.

I don`t think photography has moved forward at all, not a bit.

Again, to each his own. I'm not trying to convert you or something. There are other people who appreciate motorized cameras, built-in light meters and all the other stuff and put it to good use.

This is not a question of whether photography has moved forward, this is a question of whether we ourselves move forward.

I don't know what kind of innovation you would consider possible that (a) photography has missed and that (b) would be feasible at all from a technical point of view. I know quite a number of photographers who are perfectly happy with 1950s cameras and consider them the epitome of camera-building. It's a perfectly legitimate viewpoint to have, but we should be aware of its implications. To these people, photography hasn't progressed since then, but then again, their own ideas of how photography should be done usually leave little room for progress.

Philipp

 

[sjw617]

XPan won't allow you to change between films mid-roll.

On the XpanII you can change rolls in the middle and leave the tab out.

Steve

 

[urban_alchemist]

Why do you bother with an SWC? Just take a plain old 503 with an 80/2.8 or a 110/2 and take a couple of steps back. Lens are a couple of stops faster, you get spot-on TTL focusing, and with the 80/2.8 it's also a whole lot cheaper.

Philipp

Damn! I must have bought a dud. My 503CW doesn't have a meter!

FYI: TTL is flash-sync only...

 

[markuspd]

Ansel Adams is wrong - and you yourself are the proof. Why do you bother with an SWC? Just take a plain old 503 with an 80/2.8 or a 110/2 and take a couple of steps back. Lens are a couple of stops faster, you get spot-on TTL focusing, and with the 80/2.8 it's also a whole lot cheaper.

But then Ansel Adams is overrated anyway. 😛


65mm.


To each his own.


Well those two are technically solutions to orthogonal problems, since Hasselblad backs won't allow you to shoot 6x6 and 6x17 on the same roll, while the XPan won't allow you to change between films mid-roll.


Again, to each his own. I'm not trying to convert you or something. There are other people who appreciate motorized cameras, built-in light meters and all the other stuff and put it to good use.

This is not a question of whether photography has moved forward, this is a question of whether we ourselves move forward.

I don't know what kind of innovation you would consider possible that (a) photography has missed and that (b) would be feasible at all from a technical point of view. I know quite a number of photographers who are perfectly happy with 1950s cameras and consider them the epitome of camera-building. It's a perfectly legitimate viewpoint to have, but we should be aware of its implications. To these people, photography hasn't progressed since then, but then again, their own ideas of how photography should be done usually leave little room for progress.

Philipp

Well I think Adams was making a general comment about too much reliance on gear.
I don`t see how he can be overated to be honest but I don`t want to start on that.
SWC`s always seem to have their use even if only for tight interiors etc when you can`t step backwards, also as they are known or have been known to be one of the most versatile cameras ever made I don`t need to defend them I just love `em anyhow.
My xpan is on the way so I guess I will find out if I use it enough to keep it long term.

 

[rxmd]

Damn! I must have bought a dud. My 503CW doesn't have a meter!

I think I put the word "focusing" in there to make it clear what I was talking about. 😀

Philipp

 

[JohnTF]

Anyhow I still want an xpan, why?, its size, its a rangefinder and of course it s a pano.

Hurry, if you can, everything I hear is the camera is a hot commodity and prices are rising, you may still snag one from someone who is singing the digital blues?

Am not sure I can find or afford a second lens, and the Xpan II is even a rarer bird. FYI, but you probably knew this?

You probably also know the black marks easily, so a "user" with some marks is not necessarily an abused child.

Guy who sold me mine wants it back to resell. He carries one when he travels.


John

 

[C R Maclauchlan]

not sure I understand

not sure I understand

Kawabatnam
I have just read your question but I'm not at all sure how to answer it.

I have an xPan and an Epson scanner (V700). My results with the xPan are quite excellent...but so are the results from my TVs (35mm) so I wonder what you are having troubles with. Re the xPan's formats...the camera has a lens capable of covering twice the length of a 35mm frame. In the single frame format the opening over the film is 35mm wide from the middle...theoretically this would get the middle of the lens and be the best part. In practice however I find that any format with this camera (or the TVs) exceeds the capabilities of the scanner.

You can e-mail me and i will do my best to answer your questions

dmaclau@mac.com

 

[C R Maclauchlan]

for Kawabatnam

for Kawabatnam

I have re read your post a couple of times and think I understand what you are asking. In the 35mm format it is a 35mm with a 45mm lens and has the FOV of that combination. In the wide mode, pano, the FOV is roughly double...it "see's" twice as wide. Is that what you asked?