Problem with Linhof Multifocus Viewfinder

[emrys]

I recently bought a multifocus viewfinder (MFV) for use with my Ebony

4x5 camera. While I didn't intend to use the MFV mounted on the

camera (it wouldn't fit anyway), I was looking forward to using it to

help me quickly decide what lens to use at a given location.

 

However, after shooting a few Polaroids, I discovered that the field

of view given by the MFV did not match up to the field of view of the

lens.

 

Case in point:

 

I set up my camera to take a photograph of a single tree, and after

consulting the MFV, I opted for a 90mm lens. The camera was

positioned and movements were applied such that the tree was in the

centre of the image: in the same place that it had been when looking

through the MFV. I didn't bother to check the image around the edges

(as this was a test) and quickly shot two Polaroids, one landscape,

one portrait.

 

Looking at the Polaroids, it was immediately obvious that the image

taken using a 90mm lens on the camera was actually equivalent to a

75mm setting on the MFV. I'm aware that Polaroids backs are actually

slightly smaller that 4x5 so if anything, the images should have been

slightly narrower that the view through the MFV. I repeated the test

with a different lens (a 150mm) and got the same result.

 

As you can imagine this is pretty depressing for me, as the MFV

wasn't cheap. Is there something I'm doing wrong here?

 

For the record, this is the equipment used:

 

Ebony SV45

Nikkor 90/8

Schneider 150/5.6

Polaroid 545 Pro back

New Linhof Multifocus Viewfinder

 

Both lens were focussed at infinity.

[emrys]

Forgot to add, that I was using the MFV with the 4x5 mask, which I hope was obvious anyway.

[luis_de_santos]

Mike,I have had a similar experience with the linhof viewfinder.

I bought two hoping they will help me with quick evaluation of the field of view and decide on which lens to select .They have proven not very useful and quite inacurate particularly on the wider side.

A plain cardboard cutout as Fred Picker used to recomend works better and costs nothing,very quickly you learn how far to place it from your eye to simulate different lens sizes.

I am planing to sell my Linhof viewers for whatever I can get.

Good luck

Luis

[bob_salomon]

Which version of the Linhof Multifocus Finder? Current style with 2 rings

around the eyepiece or the old pull apart kind?

What mask? 4x5" or 9x12cm?

What Polaroid? Sheet or pack back?

Is your film negative larger then your Polaroid size?

 

That was one reason why a Polaroid Mask was offered for the Multifocus

Finder.

 

At what distance?

 

The frame size of the Multifocus finder does not increase qand decrease with

the distance setting on the finder.

[emrys]

Luis: I suspect you're right :/ We'll see...

 

Bob: the MFV is the newer kind. It has two rings, one for selecting focal length, and one for selecting distance. The mask reads 4x5" on the outside, and (pulling it off), reads "for 9x12/4x5 Cameras" on the inside. I'm using Polaroid 72 sheet film in a Polaroid 545 Pro back. My Velvia trannies are slightly larger than my Polaroids.

 

I understand the argument here, but the way I see it is that my trannies would have an even wider FOV than my Polaroids, which means that the MFV would be even more innacurate for them. (just a reminder: the problem I'm getting is that the FOV on the MFV is narrower than what the lens sees).

 

The tree in question was approx. 30 feet away (it's a big tree). I was focused slightly beyond it, so effectively at infinity. The MFV distance ring was set to infinity for both lenses (I turned the distance ring to match the color code for the lens - white for 90mm and red for 150mm).

[per_volquartz1]

Without a doubt the Linhof finder is a beautifully machined item and costly I'm sure.

 

Therefore I hate to suggest the following: Use a black card - size 8X10 with a cut out that is proportionate to the film size you are using. By moving the card towards your face or away you will simulate different focal lenths. Soon you'll learn to recognize different focal lengths based on the distance of the card from your nose.

[emrys]

I appreciate the answers so far.

 

Re: using cut out card, one of the reasons the MFV appealed to me was that I could slip it in my pocket.

[tim_atherton2]

if you are using an Ebony, you can get their titatinum viewing frames, much classier than carboard, and your LF ensamble will all match then. Flog the Linhof viewer and buy another camera with the proceeds ;-)

[peter_hamilton]

It strikes me that you may have a problem with the alignment or

setting of the finder itself, if the difference is significant between

finder and image recorded. I have just checked out the

relationship between my Linhof MFV (older type) and the Super

Technika V for which it was designed. Basically it confirmed what

I knew, but I thought I would give it the same test as you did in

respect of focal length. Like pretty much all such finders, it offers

you a slightly smaller image at any given distance from about 2.5

ft to infinity than a 5x4 film will record with all the lenses covered

by the MFV (mine goes from 90-360mm in the usual steps). This

is a safety net for those using the camera hand-held (yes, it is

possible with a Super-Technika). The MFVs are useful, but like

all such things with LF, you have to know how to use them to

best effect.

[michael_kadillak6]

This post really got me going as I absolutely love my Linhof equipment. Even though I have never had a problem with the disarity mentioned above, I got out my Master Technica with the 75, 90, 150 and 210 lenses and put the viewfinder on top of the camera and used several point light sources to carefully select the frame edge in all four directions on the ground glass. All I can say is "Remarkable Precision". I would expect nothing less from a company known for functionality in its purest form. Taking the deductive road, I cannot imagine a product that has been in production for probably 50 years that is this expensive and did not work exactly as it was designed and intended.

 

As a result, I can only deduce that the reason for your dissatisfaction with this product is as follows:

 

Given the fact that at any focal length (and particularly at 75 and 90mm) with such a considerable angle of view, without the viewfinder anchored at the precise common angle to the lens being used, operator error is a distinct possibility and most likelybly the reason for your comments. As a result of this fact, I feel that the finder is being scrutinized to an accuracy beyond its design.

 

Another point is that it appears that hand held, the angle of the eye through the finder could change the perspective slightly. On the camera, this becomes a non-event as you can only get so close to the eyepiece. The distance scales are moot for your application as they require a solid base to be effective.

 

However, in a very positive and cooperative note, if you feel that the product is not working for you, I (and many others) would be more than happy to work our a deal with you on it. Good Shooting.

[wayne_crider4]

First for now, get over the idea of using it as a handheld eyesight

for composure. Then set up your camera with a reference

subject for width and height if you can get it. Set the viewfinder on

top and move it forward or back till the image in the finder

matches the gg. Mark that spot for that lens at that distance at

whatever focal length. A brick wall for close focusing would be

usefull. Then try it at infinity with trees or otherwise as the

reference marks for width. Remember that on the older finders

there's a 6x9 grid in the middle. On my finder there's about

20mm or so between the film plane and the forward reference

point on the back of the finder for mounting. If your holding it to

your eye it has no relationship to a film plane regardless if it's

too wide or narrow. If your actuall image is wider than the

viewfinder when held at the eye just compensate. Maybe the

75mm setting will work better if you have one. Either way, when

once adjusted to the camera as you should be doing, it should

always be right when used "on" the camera. Effectively what you

are noting is that the finder would have to be in back of the film

plane to correspond to the actual image. I doubt this unless

there's a problem with the elements.

[emile_de_leon9]

I've found these viewfinders too be very helpful and accurate. Make sure you are using it right or compensate a bit for the lens in use. I even use the Linhof viewfinder on my 12x20 as in dim light the corners are always problematical with wide angles. The Voightlander finders are good too and smaller. Just get one to match your lens. I use the Voightlander 15mm viewfinder for my 165mm on 12x20 and it really helps.Its nice to use these to get quick ideas for camera/lens placement too.

[brian_ellis3]

If you're unable to use the multifocus viewfinder in the manner for which it was designed, i.e. to fit in the accessory shoe of the camera, is it possible to draw any valid conclusions about its operation?

[michael_fox]

Mike, is it possible that this is an angle of view problem? Many/most of the 90mm lenses out there seem to have a 100 degree angle of view. Yes, the newer XLs, etc. are wider - 110 degrees - but the "older" ones seem to be about 100 degrees. The Nikkor 90/8 SW has a 105 degree angle view. Most of the 75mm lenses seem to have a 105 degree angle of view. Therefore, it would not seem unreasonable for the viewer to see interpret what you see through your 90/8 SW as a 75mm lens? Does this make sense?

[michael_kadillak6]

In response to your last questions Mike, I am not sure that the number you quoted for the Nikon 90mm F8 of 105 degrees which is the covering power is synonymous with angle of view. Maybe we can illicit some expertise on this issue as you do bring up a good point.

[michael_fox]

Michael, yes, you're probably right. That is, angle of view is some function of coverage angle and focal length. I'm too lazy to do the trigonometry on this one to see if it works out to the exact problem reported (Nikkor 90mm/8 matches up with viewfinder 75mm). However, since lenses of a given focal length do vary in coverage angle, I would also expect them to vary in angle of view and to vary enough to make the multi-focus viewfinder not match up exactly to a particular lens.

[emrys]

Re: operator error (Mike K), I was standing next to the camera, and the FOV was determined from the background which was a set of hills approx. 1 mile away. I doubt that me moving a couple of feet one way or the other would have made a difference to the background.

 

Re: mounting the MFV on camera (Brian E), according to the instruction booklet that accompanied it: "...besides accurately determining the selected picture area, the multifocus viewfinder can also be used a) to determine the focal length if the location is already known. The photographer can use the viewfinder by itself to establish the focal length and selected picture area by turning the focal length right." Accompanying the text is a picture of a person holding the MFV directly to their eye, which is what I've been doing.

 

Re: angle of view / coverage (Mike and Mike), my understanding is that angle of view has nothing whatsoever to do with angle of coverage (which is dependent on the design of the lens). I have always been led to believe that angle of view is directly related to focal length for a given film format.

 

The following URL appears to back this up:

 

http://www.lighttec.com/angle.html

[emrys]

I've been taking a closer look at the MFV, and it looks like it's had a few knocks. The salesman told me it was an ex-demo model, but was in perfect working order. Well:

 

a). there's a screw missing from the distance ring

b). removing the mask, it's apparant there's a chip of paint / metal inside the elements

c). there's a scratch around the mask holder ring that has removed the paint from it

 

I've sent a mail to the supplier and I will be phoning them tommorow to try and sort out a replacement as I can only assume, based on the above testimonials, that the one I have is faulty. I will update when I get a response.

[michael_fox]

Mike T: I read the URL. It says that angle of coverage and angle of view are different parameters. Unfortunately, it uses different frames of reference for the two parameters. Yes, for a given fixed position of the 4x5 film, the angle of view of any two 90mm lenses will be the same.

 

What the article doesn't cover is that the image circle is larger than the film. Therefore, the angle of view of the entire area of the image circle is wider on lenses that have wider angles of coverage.

 

However, now that I think about it, that has nothing to do with the problem you are reporting since you're using the 4x5 mask, thereby restricting the viewing area back to the fixed case. Therefore, consider my comment withdrawn.

[jeffrey_scott]

As to the angle of view vs. angle of coverage I believe that the two are approximately the same. The angle of view of an image circle if projected on the film showing the complete circle would be about the same as the stated angle, ie: 100 degrees, 105 degrees, etc. If I were to make a photograph with my 90/8 SA on an 8x10 piece of film, the area seen of the subject would be 100 degrees, since the whole image circle can be seen (a circular image). But on a piece of 4x5 film it is much narrower since the whole image circle is not seen, just a section of it.

[george_jiri_loun]

Jeffrey, the angle of view is a function of the film format in use and the focal length of the lens. The angle of coverage is a function of the lens design thus the two are different things.

[george_jiri_loun]

Mike, one MFV which you have always with you (and yes, it slips into your pocket) are your fingers. Make with them the desired film format (as when showing to somenone how big your format is) stretch your hands out to the desired focal length, take a look through them and see... Seriously, it works! (even if it attracts strange looks from onlookers...) For me it works up to 650mm focal length... so when I need to visualise the view of my 800 mm Nikon I make the film format half its size and project it on a 400 mm distance - the result is the same.

[jeffrey_scott]

George,

 

What I am saying is that the angle of view and the angle of coverage are about the same when the whole image circle is taken into consideration. The same focal length lens would have different angles of view depending on the film format of choice, thus a 90mm lens is a very wide lens on 4x5 but only moderately wide on 6x9 for example. Regardless of that, if you were to measure the angle of incidence in front of the lens and behind the lens they would be about the same.

[peter_hamilton]

I'm relieved that Mike's problem seems to have been 'only' a

faulty MFV, because he can hopefully get it fixed by the dealer.

But I did wonder how much we (the large format community)

spent on Polaroids checking this out?

I'm also grateful to Mike because his problem made me think

about the assumptions I make when using MFVs, which I do

either on my LF equipment or my Leica Ms. One huge advantage

of this way of visualising the subject is that the image selected

through the viewfinder 'frames' it in the same way as one would

when setting up a painting or drawing on an easel, and I have

found this much easier than attempting to compose the image

on the ground glass, either of a LF camera, or an SLR. Of course

the framing card is a simple and cheap version of this, but I find

that the reduction of image size that a MFV offers 'concentrates'

the composition into its constituent elements a little more easily.

[emrys]

I'm feeling a bit guilty now for all the Polaroids that have been shot. I think it's a reflection of the LF community as a whole that people are prepared to go to lengths over an issue such as this.

 

Thanks to all.

 

I have contacted the dealer, Robert White, this morning. They have been most helpful and are speaking to Linhof as I write this. I will update as soon as they get back to me, and, assuming that I get a replacement (which judging by my previous dealings with RW seems likely), I will update with my experience of the new viewfinder.