philip_y._graham

William,

<p>

Thanks for the information. One of the reasons this site is so

interesting is not just the information on offer but also the way it

can help correct mistaken beliefs. Thanks again.

I�ve sent my Fuji Quickloads to Metro Imaging in London

(http://www.metroimaging.co.uk) for about 5 years with no problems.

Sandy,

<p>

For large format cameras there is no advantage in buying a circular

polariser and they are usually more expensive. However, a circular

polariser may need to be considered if you also plan to use the

filter on a MF or 35mm camera since linear polarisers can interfere

with the autofocus and metering systems of certain of these cameras.

<p>

I am not sure about John�s comment that linear polarisers are more

effective. My understanding has always been that there is no

practical difference between the two types of polarising filter but I

may wrong about this.

Daniel.

<p>

I agree with you that centre filters are a pain. Not only their

expense but something else for me to carry, to get lost or to get

broken. I have also ended up having to buy a separate centre filter

for each of my wide-angle lenses.

<p>

Although I can see that it is possible to improve light fall-off by

dodging in the darkroom or using Photoshop on the computer, my query

is whether this is as effective as using a centre filter?

<p>

With a wide-angle lens, the light fall-off can be up to 3 stops at

the edge of the image circle which means that if a centre filter is

not used then the edges of the negative or transparency may be

significantly under-exposed assuming the centre is correctly exposed.

As has been mentioned above, this under-exposure will lead to some

loss of detail and clarity and am I not correct in thinking that

although Photoshop can correct the difference in brightness between

the centre and the edge, it cannot restore this lost detail?

<p>

It seems to me that if you scanned and manipulated a negative or

transparency that was 2-3 stops under-exposed you might be able to

get a reasonable print but I�m not sure it would be as good as the

print that you would get from a correctly exposed negative or

transparency. In effect isn�t this what you are doing to the edges of

your negative or transparency by not using a centre filter. I suppose

that increasing the initial exposure would help to reduce the under-

exposure at the edges but at the cost of producing some degree of

over-exposure at the centre.

<p>

Since I shoot mostly transparency film (as the end product) then

darkroom or computer manipulation has not been of any particular

relevance to me but, time permitting, I have recently decided to

delve into the digital world and so I would be grateful to hear what

you feel of my beginner�s comments.

<p>

I like the elegant way you have created a gradient mask

individualised to your 72mm SA XL but I wonder how well this works

when you are using camera movements where the light fall-off problem

on the negative or transparency may become asymmetric.

<p>

As to the question above about the 90mm SA XL, I consider that if no

camera movements are being used then the light fall-off is not a big

problem and a centre filter is not always essential. However, with

significant movements I would personally always use a centre filter.

I replaced the standard focusing screen on my 645n with an AG-80 Cross-Lined Matte about a year ago.

The new screen comes with tweezers to let you remove and replace the screens. It takes about a minute to do once you work out the correct direction of pull and I don't think that most photographers would have any difficulty doing it themselves.

With a Calumet electronic shutter tester I find that all my large

format shutters are rarely closer than 1/6 stop to the indicated

shutter speed (and these are all on new and well looked after lenses).

<p>

According to Calumet this means that at an indicated speed of 1

second the actual shutter speed can range from 0.89-1.12 seconds.

This is about a 12% error.

<p>

I�ve also tested how accurate the shutter speed is on the B setting

using my wristwatch second hand as the timer at 2, 4 and 8 seconds. I

found that there was always less than a 10% error. I was never even

close to a 1/4 second error on a 2 second exposure timed with my

wristwatch. I doubt if there�s any point in being more accurate.

From Carl Zeiss Camera Lens News No. 10, Summer 2000

Is rollfilm 220 better than 120 in terms of film flatness?

Zeiss has recently developed a new measuring system to evaluate film flatness in medium format photography.

The new system is based on an computerized microscope that can automatically scan and focus on multiple points of a film frame in a medium format camera magazine. The obtained focusing data are recorded by a computer and evaluated by a propriatory Zeiss software. The result is a mapping of the film topography with an accuracy of one millionth of a meter (1 micron), according to the developer of this system.

The purpose of this new device is to find out how well film magazine mechanics are designed in today's medium format camera systems, how precise they position the film and how well they hold it flat. From these findings Zeiss can draw conclusions about the field flatness required for medium format lenses and Zeiss can also trace causes for lack of sharpness in customer's photos. This is particularly interesting since more than 99% of all customer complaints about lacking sharpness in their photos can be attributed to misalignments of critical components in camera, viewfinder, or magazine, focus errors, camera shake and vibrations, film curvature, and other reasons.

So far, Zeiss has found that film curvature can have a major influence as a source of unsharpness. This has also been known by Zeiss' camera making partners Alpa, Hasselblad, Kyocera (Contax) and Rollei. Since Zeiss' evaluation program is not completed yet, we would like not to draw too many conclusions prematurely. But two things can be stated already as hints to enable sharper photos with medium format cameras at wide open apertures, since exactly those are invited by the high level of aberration correction in Zeiss lenses:

1.

220 type rollfilm usually offers better flatness than 120 type by a factor of almost 2. This is an advantage with fast, motorized cameras like the Contax 645 AF, Hasselblad 555 ELD (and previous motorized Hasselblad cameras) and Rolleiflex 6000 series cameras.

2.

Film flatness problems are mainly caused by the combined influence of two factors: the rollers in the camera or magazine that bend the film, and the time a certain part of the film is bent by such a roller.

Camera manufacturers usually space the rollers in a way that bent portions of the film will never be positioned near the center of the image. Therefore only marginal regions of the image should be affected by sharpness problems due to film flatness errors.

Since the photographer cannot alter the geometry and mechanics of his camera, he can only influence the other factor: time. A film run through the camera without much time between exposures should result in good flatness and hence sharpness. Five minutes between exposures may be some sort of limit, depending on brand and type of film. 15 minutes are likely to show an influence of bending around rollers. Two hours definitively will.

As a rule of thumb: For best sharpness in medium format, prefer 220 type roll film and run it through the camera rather quickly.

Maybe its wrong but I do get pleasure from hauling around 10 kg of

camera equipment, sweating away under a dark cloth on a hot summer�s

day, straining my eyes to see what�s in focus on the ground glass and

then spending hours handling noxious chemicals.

<p>

However, I also enjoy the time I spend scanning my black and white

negatives onto the computer and playing around in Photoshop.

<p>

From my own results and the results of others, I am convinced that

within a few years (or even sooner) the quality of digital printing

is going to equal or even surpass traditional darkroom techniques in

all formats including large format.

<p>

But so what. There isn�t anything mythical about traditional darkroom

printing techniques. If the same or better results can be obtained

more consistently and more reliably by other techniques then it�s

time to change. I very much doubt that photographers brought up on

digital photography will mourn the passing away of the traditional

darkroom.

<p>

After all its the quality of our pictures that counts, however they

happen to be produced.

As you can see, tilts and swings produce weird and wonderful effects

on the plane of focus and depth of field. Harold Merklinger�s

book, �Focusing the View Camera� provides a good insight into this

subject although it isn�t a particularly easy book to read.

<p>

Tilts can be very useful in certain �near-far� type landscape shots

where there is a single plane which you would like to be in focus but

they may not be useful when there is more than one plane which needs

to be in focus. For example, when you have a tall foreground object

such as a tree. The use of tilts in this case may allow the bottom of

the tree and the distant landscape to be in sharp focus but in doing

so the top of the tree may well end up out of focus even if you stop

down to a small aperture.

<p>

Some photographers use mainly front tilts whereas others prefer to

use a combination of front and rear tilts. If possible try and get a

camera with both types of movements and decide which you find best.

<p>

Although I love my large format camera, I regard it as an addition to

my medium format equipment rather than an alternative. View cameras

can do certain things extremely well (especially landscape and

architectural photography) but they do have their limitations. Think

very carefully before making a move entirely to large format.

Why help out a manufacturer who discontinues your favourite film?

<p>

Better to leave them with thousands (or even tens of thousands) of

rolls of unsold film on their hands.

<p>

Try to find a manufacturer who has a long-term commitment to your

needs and support them instead.

Possible - yes. Practical - no.

<p>

As mentioned above there are a number of pre-1990 35mm SLR cameras

with spot-metering capability.

<p>

Even my 20 year old Leica R4 (and also I believe its predecessor the

R3 from 1976) can selectively meter from a central 7mm diameter

circle (about 5% of the frame) - although this only starts to

approach a one degree angle of measurement when the camera is used

with a 250mm or longer lens.

<p>

When I read your question, I wondered how the R4 camera plus 250mm

lens combination would compare to my Minolta Spotmeter F. It actually

works surprisingly well, measuring highlight and shadow readings

within half a stop of the spotmeter (although with a somewhat shorter

overall measuring range) but it weighs nearly 2kg and measures 25cm

in length - not something that would easily slip into your pocket.

Any distortion of the image, whether caused by diffraction, lens

aberration, problems with film flatness etc. will of course become

more obvious the more that the negative is enlarged.

<p>

However, that is only part of the reason why diffraction is a greater

problem for smaller format cameras when they are stopped down.

<p>

Diffraction occurs when light travels through a small opening. The

smaller the opening then the greater the degree of diffraction. When

diffraction occurs there is a scattering of some of the light which

tends to degrade the quality of the image.

<p>

But whereas the amount of diffraction that occurs is directly linked

to the diameter of the aperture, it is only indirectly linked to the

f stop.

<p>

A 50 mm lens set at f16 will have an aperture diameter of 50/16 or

approximately 3 mm. A 300 mm lens set at f16 will have an aperture

diameter of 300/16 or approximately 19 mm. Therefore the degree of

diffraction on the 50 mm lens at f16 is going to be much greater than

on the 300 mm lens at the same f stop. In fact you would have to stop

the 300 mm lens down to about f90 for the lenses to have the same

aperture diameter and so the same degree of diffraction.

<p>

Large format cameras tend to be used with longer lenses and so

diffraction is only going to be problematic when the lens is stopped

down to a greater extent. But the difference in diffraction between

the formats disappears if the same focal length lens is considered.

And to say, for example, that on 4x5 cameras diffraction does not

have an effect until the lens is stopped down to f32 or less is

almost certainly true for a standard 150 mm lens but it is probably

not true for a 47 mm lens.

How many of us would use a view camera if its only advantage was the

larger size of the negative (or positive)? With the problems of film

flatness, the shrinking availability of film types, the extra weight

of the equipment etc. combined with the excellence of medium format

cameras and films, why bother?

<p>

Of course the answer, at least for me, is the amazing control of the

image that camera movements can provide.

<p>

I enjoy the intellectual exercise of looking at a scene and trying to

visualise how the application of various movements will affect the

focus, position, and shape of the image on the ground glass (and then

seeing if I'm right). To do this successfully requires an

understanding of what each movement or combination of movements does

to the image. Whether your camera has axis or base or asymmetrical

tilts doesn't really matter as long as you appreciate that the effect

of tilting the lens does vary between the various types.

<p>

I prefer axis tilts because of the relatively minor effects they have

on focusing. Base tilts not only alter the distance between the

centre of the lens and the film plane (requiring a greater degree of

refocusing), they also inevitably produce a slight fall in the

position of the centre of the lens - so using base tilts can make it

more difficult to accurately predict what effect the sum of all

planned movements will produce.

<p>

As to yaw, I agree with Bill and Ellis that it is of little or no

relevance to most landscape photographers and all else being equal, I

would personally go for a camera with axis tilts rather than one with

a yaw-free design.

Larry is absolutely right, you can gain access to the rear element of

the lens through the rear standard once the back is removed and this

is certainly an option if you aren't changing the bellows at the same

time (although the design of the bellows on the TK45S means they can

be removed and replaced very quickly).

<p>

There is also something else to consider. Bob Salomon e-mailed me

with regards to my above reply. He considers that the rear element of

lenses, especially wide angle lenses, should never be

removed/replaced repeatedly because of the possible damage to the

delicate threads and the possible loss of shims which could end up

ruining the lens performance.

<p>

I think he has a very good point.

<p>

Although I have used the 90mm XL on my TK45S for about three years

without there being any obvious problem, everytime I remove/replace

the rear element of the lens I am acutely aware that the slightest

slip could lead to permanent damage. I am sure that by doing this

there is a potential shortening of the lifespan of the lens.

<p>

However, there are certain large format lenses - such as convertible

lenses and the Nikkor-T lenses - which routinely have their rear

elements removed and replaced and I wonder if anyone has experienced

damage or problems with such lenses.

To answer your question - I don't believe you can hand-hold a Hasselblad 501 at any of its shutter speeds and obtain consistently sharp results (except perhaps using studio flash), although you may still get good images.

For me, Hasselblad SLR = Slow Film + Tripod + Mirror Lock Up.

But if you want to hand-hold, then use fast film, the fastest shutter speed possible, use the waist level finder, cradle the camera body on your two hands holding it firmly against your chest, using the fingers of your left hand to focus and your right index finger to press the shutter release. Trying to use mirror lock up when the camera is hand-held is not a good idea. Also it is more difficult to hand hold the camera firmly if a prism viewfinder (especially the 90 degree one) is being used - you have to hold the camera higher and cannot easily use your chest for support.

There is an accessory grip available which may give extra support for hand-held shots.

I do not like monopods but many photographers find them very useful.

Hand-holding a camera does add a certain freedom to your photography - there are even some photographers who hand-hold their large format cameras. But if you do want to routinely use a MF camera hand-held then I would agree that a rangefinder MF camera is the best option. For a recent project, I took some river scenes with my 5x4 camera set up on a sturdy tripod. At the same time I took a few shots hand-held with my Fuji GA645. I ended up using the pictures taken with the Fuji - not as large or perhaps as sharp but they were better images.

Yes you can, but with some effort.

<p>

The rear element of the 90mm XL is too large to fit through the

opening of the front standard of the Technikardan 45S.

<p>

With the lens mounted on a suitable lensboard, you need to unscrew

the rear element, attach the lensboard to the camera, and then screw

the rear element back on from behind. Of course to do this means

detaching or removing the bellows which then has to be replaced.

<p>

It's actually quite easy to do in practice especially if you are also

changing from the standard bellows to the wide-angle bellows at the

same time. The main worry is that the rear element of the lens is at

more risk of damage / wear and tear.

<p>

In my opinion, there is no practical difference in lens performance

between the major lens manufacturers - the results from my Rodenstock

lenses seem as good to me as the results from my Schneiders which

seem as good as the results from my Fujinons. The main advantage of

the 90mm XL is that it has an image circle at least 20mm larger than

the equivalent lenses from Rodenstock, Fuji, and Nikon. If this is

important to you then the added difficulty of using the 90mm XL is of

little relevance.

<p>

I was told by Lihhof in England that it is possible to shave down the

rear element of the 90mm XL allowing it to fit through the opening of

the front standard of the 45S. For obvious reasons I decided against

having this done.

The instruction booklet for the GA645 is not the clearest of manuals but it does contain a lot of information in its 30+ pages. A number of the minor functions of this camera are not at all obvious until the manual is carefully scrutinised.

The older models of this camera would only give 15 exposures on a roll of 120 film, whereas the newer models give 16.

Fuji do not guarantee that other brands of lens hood will not interfere with light entering the autofocus window but if you are not having problems then there would probably be little benefit in getting the official lens hood. One thing Fuji do recommend is that when shooting with the camera held vertically, the camera grip is on the bottom otherwise the shadow of the lens cap could fall on the autofocus window causing a focusing error.

It is possible to look the AE and AF separately although it is rather fiddly.

- Press the shutter release halfway to focus on your subject.

- Press and keep pressing the Manual Focus button with one of the fingers of your left hand. This locks the AF until the button is released. (To show it is locked, the distance measurement in the viewfinder flashes.)

- Release the shutter release button and move the camera to obtain the required exposure.

- Pressing the shutter release halfway locks in this value.

- Continue holding the shutter release button halfway while you compose your shot and then press the shutter release button fully to release the shutter.

To set date and time:

1. Set Selecting Dial to P.

2. Press in Data Button to see Year Month Day in LCD (Sometimes you need to press it more than once).

3. Press Autofocus Button to make Year blink.

4. Set the Year by rotating the Up/Down Dial.

5. Repeat 3. and 4. for Month and Day.

6. Press in Data Button to see Day Hour Minute.

7. Set these as above.

To change data format (when battery is changed it resets to printing off):

1. Press Data Button until desired format appears (there are six options - Printing Off, Y M D, D H M, Exposure Data, Y M D / Exposure Data, Y M D / H M.).

2. Data sign appears in LCD apart from when printing is off.

Earlier this year I shot several rolls of film on my 35mm camera to

work out the best shutter speeds to obtain various degrees of

blurring for moving objects.

<p>

The degree of blurring is primarily affected by the shutter speed but

subject distance and the focal length of the lens do have a very

significant effect (of course so does the speed of the subject). To

obtain obvious blurring of distant moving objects with a wideangle

lens requires a surprisingly long shutter speed - sometimes 1/2

second or longer. However, close moving objects shot using a longer

focal length lens can be obviously blurred at 1/125 second. For the

type of interior shots you are planning, presumably with a wide lens,

I would start off by trying a 1/4 second exposure (equating to about

9 inches of subject movement at normal walking speed). This is one of

those situations where a Polaroid back is helpful.

<p>

From an artistic point of view I personally feel that blurring should

either be fairly obvious or not present at all. Slight blurring often

looks like sloppy technique.

Is the AF240Z a TTL flash unit.

http://phred.org/pentax/k/flashes/non-TTL/index.html

I can't help you with a direct comparison but I have also been researching these two lenses.

The Zeiss lens despite being half a stop slower than the Schneider is about 40% heavier in weight and, in England at least, the Zeiss lens costs about 10% more than the Schneider.

The Schneider lens has automatic floating element correction but on the Zeiss a manual correction of the floating elements is necessary via a secondary 'focussing' ring.

To my eyes, the MTF curves from Rollei suggest that the Zeiss lens outperforms the Schneider at maximum aperture but at f8 the Schneider has a small advantage.

I'm in a similar position to you with regards to purchasing a new medium format camera. I have also heard rumours (but nothing definite) that there may be a new 'autofocus' camera from Rollei this year.

I've personally decided to delay buying anything until next month and see what's introduced at Photokina.

The main advantage of the Sinar zoom 2 rollfilm holder is that in a

single piece of equipment, not that much larger than a Polaroid film

back, five different formats can be used, ranging from 6x4.5 to 6x12.

In England the cost is about $1800 which would buy you at least two

fixed format rollfilm backs. Which to buy depends on your

requirements.

I have used it for several months on a Linhof Technikardan S but I

understand from a review in View Camera Magazine that it does not fit

all camera backs. I would advise trying it out on your camera before

buying.

Although well designed, the instructions do need to be followed

carefully. With careful use it should give years of trouble free use

but I don�t feel it would tolerate much mishandling.

It does take time to replace the film and inserting the holder into

the film back can disturb the position of the camera. On the

Technikardan I find it works best to remove the film back from the

camera, insert the film holder, and then reattach the back to the

camera. I have noticed that with the weight of the holder (32

ounces), the back of the camera may drop slightly after the holder is

inserted. Watch the spirit levels closely and adjust as necessary.

Overall the film holder is well built but on each side of the front

of the holder are two narrow channels running most of the length of

the holder, which because of their depth could allow light to leak

through. A small amount of filler inserted into these channels has

solved this problem.