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Lens board/focus rail questions.
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misgive



Joined: 08 Sep 2009
Posts: 4
Location: Fort Wayne, IN

PostPosted: Tue Sep 08, 2009 3:44 pm    Post subject: Lens board/focus rail questions. Reply with quote

I wish to replace the 103mm Graftar lens on my Baby Century Graphic with a Graflex Optar 101mm lens. The Optar won't fit the lens board---so what lens board do I need and where might I find one at a low price? Also do I need to adjust focus settings on the focusing rail---there being a slight difference in focal length between the two lenses?? If so, what do I do?? Thanx. TOM :
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Les



Joined: 09 May 2001
Posts: 2682
Location: Detroit, MI

PostPosted: Tue Sep 08, 2009 4:10 pm    Post subject: Reply with quote

I'm guessing the lens doesn't fit the hole in the lensboard left by the Graftar. You'll need a new lensboard with the right diameter hole. I'm not exactly sure what size it takes, I'm sure others will post that.

as to where, you can try ebay, Midwest photo exchange in Ohio (www.mpex.com) or others listed on our home page.

next up is the what to do about the stops. The answer depends on whether or not you want to use the rangefinder or the focus scale.

If the answer is yes, then yes, you have to move the stops and re-adjust the range finder.

If you only use the ground glass to focus and compose then you don't really need to move them, you'll just lock the lens / front standard down a bit short of the stops and focus with the ground glass.

The focus scales that are currently on the camera are for the 103, and technically, they don't work with the 101. In practice, I contend if you adjust the infinity stops so the lens is at inf when the scales are at inf, they will be 'close enough' as long as you stop down to say f8 and don't rely on the scales closer than about 8-10ft.
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misgive



Joined: 08 Sep 2009
Posts: 4
Location: Fort Wayne, IN

PostPosted: Tue Sep 08, 2009 7:19 pm    Post subject: setting focusing scales on my Baby Graphic. Reply with quote

Les--Thanx for the reply. I use the focusing scales--haven't figured out the rangefinder yet but will. So I must adjust the scale---so, do I move the stops in the rails? Seems likely--so do I mount the camera on a tripod and manually try to focus in on a ground glass and cut new marks in the scale? Do I move the stops in the rail slide? Better yet is there a how-to book or a book with such "how to" available? Seems to me the makers of Graphic cameras would have had a lot of customers switching lenses---they'd need a lesson available to do the fine tuning----one reason why I picked up the Optar lens was my belief it'd give me sharper pics at any aperture as compared to the Graftar lens. My phone is 260-918-1951 if you can call. TOM
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Les



Joined: 09 May 2001
Posts: 2682
Location: Detroit, MI

PostPosted: Tue Sep 08, 2009 8:10 pm    Post subject: Reply with quote

Actually Graflex had different scales for just about all the variations in lenses.

the simple physics is thus: A longer focal length lens needs more movement of the lens than a short focal length lens. For instance, a focus scale for a 90mm lens shows the distance the lens moves to go from inf to say 10 ft is about 1/4", but a 250mm lens the distance the lens moves to from inf to 10' maybe more than 1/2" (I'm guessing here, don't have time to do the math)

So the error increases as you get closer to the subject.

Most of the lenses, well infact all of the lenses made have a general focal length engraved on them, the actual focal length could vary up to a couple of mm. and Graflex had different scales for the exact focal length of any lens.

In your case the difference of 2mm (or about 2mm) is only significant as you get closer to the subject. Some helpful factors are stopping down to gain depth of field, getting lucky and having the 103 really be a tad short and the 101 be a tad long in their actual focal lengths, and finally testing to see just how off the scale is at 8ft, 6ft and 4 ft.

If I were in your camera case, I'd set the camera on a tripod, set the rails so the focus scales are reading "INF" then clamp the rails down. With a c-clamp or buldog paper clip or something.

Now push /pull the lens standard so the 101 Optar is focused on something 1-2 blocks away. Lock it down. Now move the INF stops until they meet the standard.

Now you can test the scale. measure 6 ft from a target, focus the camera and see what the scale says.

I've been known to create my own scales out of high quality tape and a fine pen (Rapidiograph 6x0, but I'm dating myself) Actually a finely sharped pencil makes a very fine line, some scotch tape over it will protect it well enough.
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Henry



Joined: 09 May 2001
Posts: 1427
Location: Allentown, Pennsylvania

PostPosted: Tue Sep 08, 2009 11:55 pm    Post subject: Reply with quote

Recalibrating the Kalart is a royal pain. Consider first how you are going to use the camera. If you contemplate much hand-held work, leave it as-is; the Graftar is by far the better choice because it is self-cocking. You likely wouldn't use it with ground-glass focussing anyway because its coverage permits only limited use of perspective-correction movements. OTOH, the 101 Optar is ideal for tripod shots with gg focussing; you wouldn't use the Kalart for that anyhow, and the Optar's coverage permits full use of the Century's movements.

I speak from experience, having a Century with Kalart, and a 103 Graftar as well as an Optar 101.
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pv17vv



Joined: 22 Dec 2001
Posts: 255
Location: The Ardennes, Belgium

PostPosted: Wed Sep 09, 2009 5:43 pm    Post subject: Reply with quote

Quote:
OTOH, the 101 Optar is ideal for tripod shots with gg focussing


Henry, may I ask why ?
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Henry



Joined: 09 May 2001
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Location: Allentown, Pennsylvania

PostPosted: Thu Sep 10, 2009 1:51 am    Post subject: Reply with quote

Well, I gave some of the reasons in my post, q. v., but in addition the Optar is a much better lens (four-element Tessar type, as opposed to the three-element Graflar) capable of really high-definition enlargements on out to 12"x15". Now the Graflar is perfectly adequate when used with respect to its limitations, and the self-cocking Century shutter is mighty convenient when shooting hand-held through the sports finder, but I would never ask or expect it to yield the kind of critical results I can achieve with the Optar.
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Dan Fromm



Joined: 14 May 2001
Posts: 1863
Location: New Jersey

PostPosted: Thu Sep 10, 2009 8:35 am    Post subject: Reply with quote

Henry, you're repeating the conventional wisdom. I shared it until I did some formal lens testing. Y'know, with USAF 1951 targets and all that.

Because of problems with the tests as I ran them I'm not as confident of the results as I'd like to be, but my 103/4.5 Graflar tested better than my beloved 101/4.5 Ektar. Significantly better. I don't think I'm the only person to have got this result.

We know from tests -- not mine -- of other Wolly and EKCo lenses that Kodak made better tessar types than Wollensak. So if I were the original poster I'd use my Graflar and be happy. If I were internally consistent and didn't have a heap of normal lenses for 2x3, I'd retire my little Ektar and use my Graftar.

I've settled on a Symmar type that lives, alas, in a #1 shutter; a 2x3 Graphic won't close with it mounted. But, and this is a point that we obsessive accumulators and testers often miss, one could be happy with any of the lenses I've mentioned. They're all better than good enough to use.

Cheers,

Dan
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Henry



Joined: 09 May 2001
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Location: Allentown, Pennsylvania

PostPosted: Thu Sep 10, 2009 3:28 pm    Post subject: Reply with quote

OK, pv17vv: there you have it. The OP can try both and compare the results. As for me and my requirements, I can't use a lens that doesn't permit even small amounts of front rise without vignetting at the corners. Thus the Optar on tripod, etc. OTOH, for hand-held it's the Graflar in Century, for reasons stated.

Dan, you could very well be right about your particular samples of those two lenses. Conventional wisdom, borne out by experience, tells us that sample variations can account for widely differing results, however. And to tell the truth, I've never tried to enlarge an image taken with the Graflar to anything much bigger than c. 3.5" x 5". Maybe I got lucky with my Optar, but it's very sharp, and it does everything I need it to do---as does the Graflar, each in its own special way.

Later correction: Graftar, not Graflar, is what I have.
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Dan Fromm



Joined: 14 May 2001
Posts: 1863
Location: New Jersey

PostPosted: Thu Sep 10, 2009 4:28 pm    Post subject: Reply with quote

Henry, I just checked, mine is a Graftar too. I've got to be more careful.

Cheers,

Dan
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Henry



Joined: 09 May 2001
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Location: Allentown, Pennsylvania

PostPosted: Thu Sep 10, 2009 5:57 pm    Post subject: Reply with quote

I wonder what, if any, difference there is between them? I believe both are triplets, but beyond that---?? FWIW, the 1954 (10th) edition of "Graphic Graflex Photography" mentions only the Graftar (e.g., pp. 17, 30), at least according to the index.
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misgive



Joined: 08 Sep 2009
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Location: Fort Wayne, IN

PostPosted: Thu Sep 17, 2009 6:35 pm    Post subject: lens board/focus questions Reply with quote

Thank you all for the various suggestions---I will test the 101mm and 103mm lenses to see if they are significantly different in resolving power---then if I decide the 101 is better--I'll try to figure out the focusing scale. The 101 has a 400th shutter which interests me---I already use a well used Medalist II (modified for 120 film) with 101mm Ektar which is a good lens mounted on a 400th shutter. Just trying to bring the Baby G up the Medalist level.
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Dan Fromm



Joined: 14 May 2001
Posts: 1863
Location: New Jersey

PostPosted: Thu Sep 17, 2009 7:30 pm    Post subject: Reply with quote

Um. er, ah, y'r Medalist's 100/3.5 is a heliar type (5 elements in 3 groups, nearly symmetrical) lens. The 101/4.5 Optar is a tessar type (4 elements in 3 groups, quite asymmetrical).

There's disagreement about whether the 101/4.5 Optar is as good as the 101/4.5 Ektar, also standard issue for 2x3 Pacemaker Graphics. To the extent that there's a consensus it is that the Ektar is better, and that the higher quality is most noticeable towards the edges of the image. Some say it depends on the individual lens; Wollensak QC wasn't as good as EKCos, and it seems that some Optars are better than others.

So what? Well, there's a consensus that the 105/3.7 Ektar (essentially the same lens as the Medalist's 100/3.5) is better than the 101/4.5 Ektar. I have two 101/4.5 Ektars in hand, also one 105/3.7 and have had another 105/3.7 that I sold because I thought the 101s shot better. I later repented, got the 105 I still have.

As best as I can tell my 101/4.5 Ektars produce better image quality, in the center of the image and even more so towards the edges, than my 105/3.7. And as best as I can tell my 103/4.5 Graftar is actually a little better than my 101/4.5 Ektar. So much for the popular wisdom.

So your Century with its 103 Graftar is likely, if you can focus it, to shoot better than your Medalist. I'm not sure where your 101 Optar will come out in all this.

Good luck, make your own decisions,

Dan
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misgive



Joined: 08 Sep 2009
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Location: Fort Wayne, IN

PostPosted: Fri Sep 18, 2009 7:58 pm    Post subject: Reply with quote

Dan--Thanx for the correction. Yes the F3.5 Medalist Ektar is 100mm. Blinkus of the thinkus---thought it was 101mm. Anyway, I like the Medalist. I felt the Graftar was inferior. Maybe not. We'll see. Maybe It'll turn out the Graftar is a great lens and I won't have to frog around with focusing scales! The very best lens I've ever used in large format was on an old Kodak folder--116 film--f7.7. Forgot the focal length. I was about 13-14 years old. HA.
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glennfromwy



Joined: 29 Nov 2001
Posts: 903
Location: S.W. Wyoming

PostPosted: Sun Sep 20, 2009 3:06 am    Post subject: Reply with quote

I had a a 103 Graftar. It was quite sharp and contrasty. Until the shutter crapped out. I think I still have the cells in my box-o-stuff. Some of the various triplets can be very sharp indeed when stopped down. For example, I recently returned from a shoot with a 135/4.5 Zeiss Novar. Usually regarded as too silly to consider, the 4X5 negs are tack sharp. This one is a strange configuration I've not seen before. Coated, too. Anyhoo, I think, if not mistaken, the 103 Graftar is a 4 element lens. The Graflar was the low end budget triplet. Do your test shots. You may be pleasantly surprised.
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