bernard_lazareff

Normally, I dislike such "pseudo-HDR" images with enhancement of local contrast. But... that one is so much over-the-top as to make iv a viable proposition in the "abstract" genre.

No, It's still the same physical aperture, maximum. But, as seen from a point in the focal plane, the aperture "circle" (technically, the exit pupil) is farther (because the lens moved forward), and therefore looks smaller and delivers less light in the focal plane. This feature of the 35/2.8 spares the user the calculation of exposure compensation.

This is going to be much more expensive than buying another 180mm lens. Bought one 1 year ago at photo fair for (IIRC) 80€. How many hours do you think (probably underestimate) it takes to fabricate a lens within specs (assuming you have the specs)? How much do you pay for qualified manpower, e.g. a mechanic (likely an underestimate compared with a qualified optician) repairing your car? Make the product of these two numbers... Plus, the optical elements of the viewing and taking lenses are supposed to be identical (they better be, if you hope the focus to be correct). So why not exchange the elements (both front and rear) between taking and viewing lenses? Depends on the kind of damage (you did not specify that) but possibly the damaged lens is good enough for focusing and framing.

+1

1/3 of an f-stop. (with due respect) The rest of Alan Marcus's post is 100% valid, including that even 1 stop overexp would be nothing to worry about.

Don't feed the troll.

+1 +1 to getting thin plate glass from a picture framers, or just any decent glaziers. Also consider this is your opportunity to transform your V700 into a V750. At least hardware-wise. Just ask your supplier for "museum glass"; Expensive stuff, almost reflection-free. Gone the flare, the actual Dmax might be closer to the advertised specs. As concerns the thickness. Say you replace 2.5mm glass by 2mm glass. The first-order effect is that the sensor optics are now (0.5)x(0.5)=0.25mm closer to the film. (one of the (0.5) is the difference in thickness; the other the glass index minus one). This should be within the range of the holder adjust. If you can find 2.5mm, even better.

Discard when the clearing time is twice what you measured with fresh fixer. Don't wait until fixer becomes dark (never saw that for fixer) or has solids floating.

This. The woman in background should also be "burned ou, as suggested above by rodeo_joe. But I don't feel like firing up PS.

@allancobb: what is the plane(s) on the first image of your post #10? I see two front-facing propellers (unlike the B-36 on the second photo) and two pod-mounted jet engines. First reaction is they belong to distinct planes, but the shadow on the ground is of a single wing. What is that frankenplane? A test bed for early jet engines? Splendid tonality in the metal and the clouds.

Remember (see my first post) this is not for viewing stereo pictures. Both eyes are looking at the same point in the space just in front of the ground glass, as i could check with my finger. "pseudo-stereo" effect Maybe; maybe also promotional language relieving eye strain I'm more inclined to believe that stereo pictures in one frame, (...) need a way to view them. unfortunately not. By the way, when I wrote "I came across" in the original post, this item is on sale at our local charity, where I manage the photo section. And, in the same display, there is a real stereo viewing device.

Cool factor: Penti. Half-frame. Exists in many funky (East German) colors. Requires Rapid cassettes. http://cameracollector.proboards.com/thread/7002 Class (however you define that): Voigtlander Vito IIa.

Slides: possibly, probably. Microscope slides: not enough magnification. That is probably the idea of that device.

I came across the object shown in the picture. Binocular vision, but of a single image. Each eye is redirected to the central are via prisms (definitely) and a semi-transparent mirror (presumably). The plane of focus is somewhere in the gap between the bakelite body and the piece(s) of ground glass. Sure, even without stereo vision, binocular viewing is more comfortable than squinting, but, is it worth the extra complexity? Has anyone seen such a device before?

I would have thought that for toning, the bleach should be re-halogenating, i.e. include some bromide. And, when doing ordinary bleaching with ferricyanide, the effect materializes when the print is put into fixer (sometimes to diiscover it's over-done). For instance, here is the bleach part of the thiourea toner, from Anchell's Cookbook. Bleach: Water at 125F/52C, 750.0 ml Potassium ferricyanide, 50.0 g Potassium bromide, 10.0 g Sodium carbonate, monohydrate, 20.0 g Water to make 1.0 liter This solution should be stored in the dark as ferricyanide solutions are light sensitive. Should the solution turn blue the bleach should be discarded. Try adding 10g/l of bromide, as suggested by Alan Marcus above. You should see a prompt bleaching action. You could also try taking one of your ferricyanide-only bleached prints into fixer and see the bleach action, but that one cannot be toned any more because the silver halide is gone!

@ Mike; I also agree.

<blockquote> <p>the biggest problems I faced haven't been addressed in this thread: film flatness and Newton rings. If you taped down the film to get it as flat as possible, Newton rings spoiled the scan. If you used a film holder that kep the film off the glass, only part of the image would be in sharp focus.</p> </blockquote> <p>Better Scanning holder. Piece of "anti-glare" glass (actually lightly frosted) from arts/framing store, cut to width of film (60mm). Film strip ends taped with back against glass. Deposit film down (emulsion down) in channel of B.S. holder; channel edges plus residual curvature take care of the long sides of the film strip, results in film flat against glass surface. Need to activate mirror option in scanning software.<br> Once-for-all focus adjust of B.S. holder. USM restores spatial frequencies where FTM of scanner is dropping; of course, totally absent information canot be resurrected, but the improvement is significant. I can display side-by-side a hybrid workflow print and an enlarger print (Componon lens) from same MF format: no obvious difference in quality either way.<br> Not disputing that a digital MF image (or even FF 24x36) would be sharper and generally "better".</p>

<blockquote> <p>For front element focusing lens, the relationship between the front element rotation angle vs distance is more complex</p> </blockquote> <p>Not so. In either case, the moving element (whole lens or front element) must image the object onto a predermined plane; either film plane (unit focusing) or the conjugate of the film plane through the non-moving elements (front cell focusing). Just use for "f" the focal length of the front (moving) cell.</p>

<p>How about explaining your problem/question using sentences, paragraphs, etc?</p>

<blockquote> <p>I think, that in the Exaktas and Exas that I have, the image plane is in the Camera body and not in the View Finder.</p> </blockquote> <p>I don't think so. Please look at: http://www.ebay.fr/itm/Original-Exa-Lichtschacht-waist-level-Finder-inklusive-Focusing-Screen-/151894115776? (second pic) or http://www.ebay.fr/itm/Viseur-de-poitrine-capuchon-Jhagee-EXAKTA-ou-EXA-bon-etat-/282246688408?hash=item41b736ae98:g:CeEAAOSwV0RXr0aR (third pic, also showing how the leafsprings (#1 in my OP) grab the sides of the ground glass.</p> <blockquote> <p>Besides, EXAs are exceedingly easy to find at flea markets in Germany for next to nothing.</p> </blockquote> <p>That low market value is in fact the problem. Please keep in mind I'm not restoring an Exa for my own use; in which case I'd rather buy this: http://www.ebay.de/itm/Exa-Ihagee-Dresden-inkl-Jena-50mm-1-2-8-Objektiv-lichtschachtsucher/252623428491 with the nice little "handbrake". But I've sworn to myself not to start a new system beyond Nikon, Canon FD/FL, M39 and M42 (no restrictions on fixed-lens rangefinders, eh eh). And, I found out that a reflex camera without at least diaphragm pre-selection is very slow/inconvenient. But I digress.<br> As I mentioned in the OP, I am preparing (trying at least) this Exa to be sold at the local charity. Exa aficionados are rare in this semi-rural location; most potential buyers just want a camera that works and is cheap. Investing 15€ (postage!!) into a viewfinder for a camera that will be on sale for maybe... 15€ and may sit on the shelf forever is a risky gamble.</p> <p>Thank you all for your contributions.</p>

<p>@ Subbarayan: Thanks for the hint re:Praktika. Actually, I have somewhere two Prakticas, one of which does not work, and might donate an organ. <br> Re: the split image focusing screen, I might be tempted; but:<br> (a) The camera is to be sold at a charity, who knows if it can find a buyer for ~20€??<br> (b) The Tessar has no pre-selection, making the split image inoperative beyond (I guess) f/4. <br> I'll keep you informed concerning the transplant Praktica -> Exa. If it does not work out, there are other options on the auction site. </p>

<p>Thank you JDM von Weinberg for this fast response.<br> The article on wrotniak.net discusses at some length the compatibility between finders and bodies, but one has to read between the lines to some extent to conclude that screens are fully interchangeable.<br> My Ebay options are constrained by (a) I reside in Europe, and transatlantic postage is prohibitive; (b) I would rather have a ground glass/lens combination, that should be brighter over the whole field. But still, I see there are quite a number of screens for sale. I failed previously because I searched for "ground glass exa". Anyway, repeating the search I found this: http://www.ebay.fr/itm/Viseur-de-poitrine-capuchon-Jhagee-EXAKTA-ou-EXA-bon-etat-/282246688408?hash=item41b736ae98:g:CeEAAOSwV0RXr0aR that looks pretty good, including the field lens.<br> Many thanks again. Maybe I'll be tempted to buy that Exa for myself. Though, I would prefer the first "Rheinmetall" version.</p>

<p>Now for the back side. I have annotated potentially relevant elements:</p> <ol> <li>Leafsprings, one pair along each of the long sides;</li> <li>Protrusions from the wall, one pair on each of the long sides;</li> <li>Cylindrical rivet heads(?), one pair on each of the short sides;</li> <li>Dual piano wire springs, one on each of the short sides.</li> </ol> <p>What parts play a role, and which role, in holding the GG, with the image plane at the right place? Thank you in advance for relevant information.</p><div></div>

<p>I have this Exa I hopefully to be put up for sale at a local charity. But the waist-level viewfinder appears to be missing the ground glass. Procuring the missing part is not economically viable. But I have some more recent reflex cameras, some beyond repair, from which I might steal a fresnel/groundglass. Or I could cut a piece of plain ground glass, but the luminosity might be poor. Either way it will not be historically correct.<br> I have two closely related questions to the knowledgeable persons (hmm who could that be?) on this forum:</p> <ul> <li>how is the fixation of the GG arranged in that Exa I v/f?</li> <li>how is the GG image plane mechanically defined?</li> </ul> <p>I attach two pictures: one from the top side to help identify the model, the other from the back side. </p> <div></div>