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Ross Martin
19-Feb-2001, 14:17
Hello All,

I shoot a lot of 4x5 transparency landscapes and am considering the tremendous c ost savings in film and processing by switching to 6x9cm (using a roll film back in my view camera). Other advantages would be access to excellent new medium f ormat scanners, ability to easily bracket when needed, ability to use wider aper ture for equivalent depth of field and get faster wind-stoppong shutter speeds, much wider availability of film emulsions, and less weight and bulk of film.

I have rented and used a roll film back but am still undecided. I would appreci ate hearing from any of you who have shot extensively with 6x9 or 6x7 in a view camera (I must have movements). What are the good and bad points in actual fiel d use? How is your print quality compared to 4x5? Do you get used to that tiny ground glass image?

Thanks for your input.

Mark_437
19-Feb-2001, 14:52
My experience with the Calumet C2 back was less than satisfactory. Besides problems inherent to that particular model (sharp bend in film path, uneven spacing, etc.) I found that the accuracy of the rollback-to-camera spacing with regard to film registration had pretty sloppy tolerances (i.e. things weren't so sharp).

I don't see how you can "use wider apertures for equivalent DOF", especially since you'll be enlarging your film to a greater degree for same-size prints vs. 4x5 film.

It wasn't too hard to get used to the GG image. I made a mask out of a piece of (black) scrap 4x5 film to go over the GG.

Good luck,

Ross Martin
19-Feb-2001, 16:19
Mark,

For the same subject magnification and same aperture, there is less depth of field as you move up in film size. For example, without using movements, you would need to stop down an additional 3 2/3 stops in 4x5 to equal the depth of field of the same shot in 35mm. By my calculations you need to stop down about 1 stop less in 6x7/6x9 compared to 4x5, thus offering 1 shutter speed faster and also giving less sharpness-degrading diffraction and more resolution(helping compensate for the fact that you are enlarging your 6x9 more compared to 4x5).

John H. Henderson
19-Feb-2001, 16:55
The conventional circles of confusion used for various formats to calculate depth-of-field already take into account the amount of magnification. (e.g., 0.025 mm may be be used for 35mm, and 0.1 mm for 4x5 [or am I off my an order of magnitude?) Anyway, I think the equations for near distance and far distance are:

near distance = hd/(h+d)

far distance = hd/(h-d)

where h is the hyperfocal distance and d is the actual distance at which you are focussed.

h = f*f/(N*c)

where f is the focal length of the lens, N is the f-number, and c is the circle of confusion.

It's the square of the focal length that causes the big depth-of-field difference between formats even when adjusting c for the amount of enlargement. A "normal" lens for 35mm format is 43mm (f = format diagonal) and is about 150mm for 4x5. Square those numbers and you get a big difference in the hyperfocal distance.

(BTW - look up those equations before you take them as gospel - I'm recalling them from memory. And I think there are simplifications involved that assume that you are focussed many focal lengths from the camera so whether you're measuring from lens board or film plane is no important.)

I haven't tried 6x9 yet, but am tempted to. Your reasons sound good and legitimate. In the end, it's what works for you. I wonder if the difference between 6x7 (or 6x9 or 6x12) and 4x5 is enough to notice for anything I do. I don't see making 30x40 prints. One of my motivations would be to reduce camera size, too, in addition to those you stated. Furthermore, if you go along with the generally-accepted practice of allowing your circle of confusion to get larger as format gets larger, you're cancelling some of the increase in sharpness that you can achieve. That's always bothered me from the first time I read that CoC should vary with format size.

Paul Schilliger
19-Feb-2001, 17:16
Ross, I have used a Wista 6x9 back and the shots are very sharp. I enlarge them up to 14 x 20 with plenty of details (of course a full 4x5 has more detail). I simply marked the corners of the forma t on the sleek side of my GG with a permanent marker. As you say, it's a great cost saving solution, along with the other advantages you mention. Something to consider is the possibility to bracket and to try take from differe nt angles, which leads in more choice and more chances to have a good one. I would highly recommend for stock, unless you use a medium format along with the view camera.

Jeffrey Goggin
19-Feb-2001, 17:20
Assuming you have modern, high-quality lenses, one other benefit of shooting in the 6x? format is that even with movements, you're only using the center portion of the lens, which is usually sharper than the edges. On the other hand, if you own only older, lower quality lenses, as I unfortunately do, then you may notice a slight loss of resolution as compared to your 4x5 originals since 6x9 will have to enlarged more for the same size print. (This is especially true if you intend to crop your 6x9 and 6x7s to 4x5 proportions.)

Although my experience with the 4x5 format is limited, I own a Toyo 23G view camera -- a scaled-down 2x3/6x9 version of their 45G, thus its model designation -- and have plenty of experience with the 6x9 format as I shot with a Galvin 2x3 and Century Graphic in the past. For prints up to 16x24, which is about as large as I've had made, I have no complaints about the 6x9's image quality. Friends have had 20x30 prints made from some of my 6x9 originals and they seem happy enough although IMO, that's probably pushing things a bit too far.

If you're coming from 35mm, as I was when I bought the Galvin a few years ago, the 6x9 ground-glass will seem quite large. Although it does make using a loupe somewhat difficult, I recently abandoned the darkcloth-and-loupe approach in favor of Toyo's monocular viewer.

It isn't all that bulky to carry, is much lighter than a dark cloth, has a built-in low-power magnifier and overall, makes the camera so much easier to use, especially during hotter weather (important here in Arizona!), that I don't know why I waited so long before trying it.

The only complaint I have -- and this is somewhat camera dependent, of course -- is that I find it a PITA to remove the ground-glass in order to mount the rollfilm back. Some cameras, such as the Galvin, let you slide them under the ground-glass, as you can with the film holders on your 4x5, but most require you to remove the ground-glass assembly. I understand that some high-quality backs are thin enough to fit under the ground-glass -- Sinar zoom, Linhof Rapid Rollex, etc. -- but they are also quite costly compared to those from Horseman, Mamiya, etc., hence the reason why I haven't looked into this any further yet.

Ken Burns
19-Feb-2001, 17:43
I have used a Calumet roll film back with my 4x5 field camera quite a number of times. I usually shoot 4x5 B&W, but sometimes I use the roll film back for color transparencies. The only real problem I have had is with the shorter focal length lenses. Since the 6x7's equivalent focal lengths are about half the 4x5's focal lengths, my shortest lens (65mm) doesn't always turn out short enough. In the 4x5 format, 65mm is unltrwide, but in the 6x7 format, it is only moderately wide. This is the shortest lens I can use on my field camera, so if I need a wider lens for the 6x7 format, I'm just out of luck.

Ellis Vener
19-Feb-2001, 21:09
I use a Horseman 6x9cm back on my 4x5 Arca-Swiss and Canham DLC cameras. I've also used the Horseman 6x12 back and the Sinar 6x7cm rollfilm back.

The gross difference is the need for shorter lenses. A 65mm lens with a 6x9cm is the equivalent of a 90mm on 4x5.

The next difference as someone else has already pointed out is the need to use different standards of what you consider sharp --i.e., smaller circles of confusion.

With the 4x5 cameras I don't really feel confined by the smaller groundglass, As a matter of fact it makes it a little easier for me to consider other compositional options. Both the Canham and the Arca have well defined, and for my 6x9 film back, accurate frame markings. But I do take a little more time checking focus. And fortunately the film plane for my Horseman back, for the Fuji Quick Load holder and for the Polaroid 545i back all coincide. This is worth testing.

Ken Burns
19-Feb-2001, 22:56
Actually, a 65mm in the 6x9 format is about equal to a 120mm in 4x5.

Glenn Kroeger
19-Feb-2001, 23:10
Ross:

I liked 6x9 so much, I sold my 4x5 and got an Arca Swiss 69FC. While you might not want to go that far right away, roll film does have its advantages. You are correct that you get approximately 1.2 stops of extra DOF, assuming you use lenses that are about 2/3 the focal length for 4x5

You also get to use just the juicy center of nice lenses. The 55 Apo- Grandagon has the same angle of view of a 24mm on 135. I also like long focal length lenses, and with 6x9, the equivalent lenses are smaller, faster and I have alot less bellows/camera to sway in the wind. Combined with that one extra stop, I get shots I could not get with 4x5 in windy conditions (are there non-windy conditions?).

You also have a wider selection of films, for example some of the new fast color negative films, and Provia400F.

I find that with Velvia and Provia F, scanning on a Tango scanner and printing on a Lightjet, I cannot see a difference unless I go to sizes greater than 16x24. At 20x30 the difference is just barely perceptable, and I can make very satisfying 24x36 inch prints.

Film flatness is critical. I cannot recommend the Calumet backs. I used one for several years on a 4x5 camera with unreliable results. My results with Horseman backs on the Arca are drastically better. If you want a slide-in back, you can try the Toyo if your camera has enough opening under the ground-glass. The Toyo has excellen film flatness but is very thick. Or, the Sinar holders are superb, but very costly.

Glenn Kroeger
19-Feb-2001, 23:11
P.S. The Arca binocular viewer solves the problem of the smaller ground glass as well as some problems with my aging eyes.

Wayne Crider
20-Feb-2001, 00:48
Ross I use a Century Graphic with a roll back on all the time. I shoot landscapes using the sportsfinder and have very good accuracy. I never carry a darkcloth, just a magnifying glass for GG shots if needed and I get them tack sharp. I can handhold the camera easily and I shoot by scale usually. I use a 80mm componon in shutter for closeup's. I don't think the 4x5 will be getting much use from now on, as this unit is so light that I can carry my Nikon outfit with it and have room for sandwiches and a raincoat to boot in a small backpack. Only problem is the short bellows. Best way to go for landscapes, and the film is easily and cheaply processed anywhere. You'll love the format.

paul owen
20-Feb-2001, 14:35
Ross, Strangely enough I am considering the reverse!! I've just returned from a trip this weekend. Because of the distance, 1400 miles round trip! I took along my silvestri (6x9) as well as my 5x4. I have not used the silvestri for a few months and when I used it this time I had a real shock....the GG is SO SMALL! I also took along a 6x12 horseman film back and had a similar shock when I slipped the mask onto the GG. I have been shooting 5x4 exclusively for the last 6 months and my roll film backs have not seen the light of day. I guess I have got very used to the larger screen area. In fact, on a few shots I could have gotten used to 10x8!! I for one would not trade down, despite the advantages that you mention.I would consider trading in the silvestri!! (after my GG shock) but would still keep the roll film backs, just in case! Regards Paul

Trevor Crone
20-Feb-2001, 16:04
Ross, I use both 6x9 and 4x5 with a 6x9 back. The 6x9 field camera (Ebony SW23) comes into its own with regards to less weight/bulk. Its disadvantage is the ne ed for some kind of mag. viewer because the GG is small so I find that it's slow er to use then my 4x5 (Ebony SW45). Although here again things are slowed down b y the need to remove the GG back to mount the roll film back. For what its worth I use Horseman backs which I find to be most reliable.

With regards to "quality" I find my 6x9 work equals my 4x5 providing I don't ove r enlarge the image. All film stock (120/45) is processed with the same develope r. Regards,

Ellis Vener
21-Feb-2001, 06:21
"Actually, a 65mm in the 6x9 format is about equal to a 120mm in 4x5. "

Nope. And I've got the film to prove it. The angle of view as measured along the long side of both formats is the backbone of my contention that the 65mm (on 6x9) roughly equals that of a 90mm (on 4x5).

Ken Burns
23-Feb-2001, 16:06
Ellis: Nope, you're wrong, and I have the film to prove it. You're contention based on the angle of view along the long dimension of the formats is invalid since the aspect ratios of the two formats are not equal. For the same reason, comparison of the diagonal dimensions of the formats is invalid.

The best and most valid comparison of two formats with different aspect ratios is made based on the linear magnifications of the two formats and the lens focal lengths necessary to produce these magnifications. Based on this valid approach of comparison, the 65 used in the 6x9 format is undoubtedly far closer to the equivalent of the 120 in the 4x5 format than the 90. Of course, in doing the indisputable mathematical computations, I did round off the focal length to one that is readily available.

Bob Eskridge
23-Feb-2001, 18:51
It seems that the arguments are from using two different methods of angles of view. One is the horizontal and the other is diagonal.

Due to the fact that I also use square format often in landscape and architectual photography, it is important to compare a lens' angle of view solely on the horizontal measurement. And I do this by comparing them to the 35mm format equivalent.

A 120 lens on 4X5 (which is 120mm long on the long dimension) is 120/120 = 1.00 X 36mm = 36 (or a 35mm lens in the 35mm format.

Likewise a 65 lens on 6X9 converted to 35mm format is: 65/82 = .79 X 36mm = 28.5 (or a 28mm lens in the 35mm format.

A 90 lens on a 4X5 using the same ratios is equivalent to a 27mm lens in a 35mm format.

The above is important in my experience for architecture and landscapes. In portrait photography however a comparison of DIAGONAL angles of view tend to be more useful. A 80 mm lens on a Hasselblad is "normal" for people but often to long for landscapes. (44.5mm equiv. in 35mm format and 52mm the horizontal equivalent to 35mm.)

Hope this is clear.

Ken Burns
23-Feb-2001, 20:11
Let us say that we are planning to shoot a photo of a car once owned by Elvis. We need to shoot it in both color and B&W. We plan to make 8x10 prints from both negs, and we want the final image of the car to be 8 inches long in both prints. We will shoot the color neg with a 6x9 format camera using a 65mm lens. The B&W negative will be shot using a 4x5 camera. What focal length lens will we need to use on the 4x5 camera.

When the 6x9 neg is enlarged to 8x10, the shorter dimension of the neg (which is usually about 55mm) will determine the linear magnification required to make a full 8x10 print. That magnification is about 3.7X. To make the car 8 inches long in the final print, the image on the negative will need to be about 2.1" long.

When the 4x5 neg is enlarged to 8x10, the shorter dimension of the neg (which is usually about 95mm) will determine the linear magnification required to make a full 8x10 print. That magnification is about 2.1X. To make the car 8 inches long in the final print, the image on the negative will need to be about 3.7" long.

Since differences in image magnification are proportional to differences in lens focal length, the 4x5 camera will require a lens that has focal length that is about 1.8 (3.7/2.1) times the focal length of the lens used on the 6x9 camera. The 4x5 camera will require a lens that has a focal length of about 117mm (65mmx1.8).

I elected to call that a 120mm lens. However, because of some inaccuracies resulting from rounding off, I might have been better off to have said a 115 or 110 since these focal lengths are also readily available. But 90mm definitely is definitely incorrect.

Glenn Kroeger
23-Feb-2001, 21:36
Ok guys... calm down... obviously you get different answers if you compare short or long sides, or diagonals when the formats are of different proportions.

If you take the size of image area on a 4x5 to be a Fuji Quickload, you get about 94x117 mm of usable image. A Horseman 6x9 back give about 55mm x 82mm. So the short side ratio is 94/55 = 1.7, and the long side ratio is 1.4. If you like a 3:2 ratio in your images, use the 1.4 factor, if you always print 5:4 ratio, use the 1.7 factor.

In practice, I find 1.5-1.6 to be a reasonable factor. A 75mm lens on 6x9 behaves pretty much like a 120mm lens on 4x5. A 55mm lens on 6x9 behaves like a 75mm on the short side of 4x5, and a 90mm on the long side of 4x5.

Erik The Viking
24-Feb-2001, 16:56
Please enlighten: what would the equivalent focal length of 65mm in 6X9 be in 4"x5" if I were to use 11"X14" paper? In Europe, the 8.5"X11" and 12"X16" print paper sizes are also popular; what is the equivalent angle in 4"X5" then?

I am confused.

Glenn Kroeger
24-Feb-2001, 23:15
Eric:

Here is how you do it:

11x14 is more square than 6x9, so the short side determines the enlargement. 11 inches is 279.4mm from 55mm (short side of 6x9 film area) of film gives an enlargement of 5.08 from 6x9.

From 4x5, you have to use the long side, so 14 inches is 355.6mm from 117mm of film (based on the long side of a 4x5 from Fuji Quickload) gives an enlargement of 3.04.

So the ratio is 5.08/3.04 = 1.67.

So the 65mm would be equivalent of a 108mm lens or closest to a 110mm.

In practice, a 100mm, 110mm or 115mm will give similar views.

John Cooper
16-Sep-2001, 19:53
Ross: As the tragic week continues to unfold, today (sunday) the weather here in Florida suddenly turned sunny as a cold front replaced the very wet storm of the last few days.

I took my Technika V 6X9 with 7 lenses and 3 film backs out onto the Acosta Bridge overlooking downtown Jacksonville to shoot the same scene on each lens and each film back; 120 Agfa Scala (200); 120 Kodak 400BW; and, 220 Fuji NHG II (800). I had loaded the faster films earlier, expecting the foul weather to continue. It took about an hour and twenty minutes to shoot 21 shots from the same viewpoint, plus 6 more of another view. The quick lever removal for the back made the change from focusing back to film back very quick. The 7 lenses I was testing were as follows 65mm Super Angulon F:8, 75mm Super Angulon F:8, 80mm Noritar F:2.8, 105mm Zeiss Tessar F:3.5, 165mm Dagor F:6.8, 180mm Tele Arton F:5.5 and 240mm Tele Xenar F:5.5.

I find that the ease of use and ability to fine focus on the ground glass exceed my prior use of Technika V 4X5 and its lenses; also the weight of the outfit is more manageable for the walk up the bridge.

120 and 220 film is great for projection in the 6X7 format and the 6X9 format is closer to the 35mm format than 4X5. I still use 4X5 for indoor use, specifically Fuji 64T in Quickloads for copying art work, but for outdoor projects I think I will be using the 6X9 gear most of the time.

I would like to reduce my lenses to an 80mm Super Symmar XL and a 120mm Super Symmar HM both of which can be used on 4X5 and at a stretch on my 5X7 Kardan with or without its 4X5 back.

Best wishes in your 6X9 exploits,

John