Project Logs

Collapse

• Third test

  [zit] Olivier Gade • 06/01/2022 at 18:07 • 0 comments

  From another point of view, close to the red super moon raising axis I'd like to shoot for my son's birthday (he's in Japan and can't see it).

  There's again a lot of wind, but I'm beginning to like that lens a lot, it gives incredible compression of the space.

  Ok, there's so much wind that the crane's been moving, so I had to adapt my frame.

  For the speed, it's good, but there's a blurry trouble.

  I finally had to go inside as the firs rain in a month arrived just for the raising moon schedule.

  Next day, from inside, the air is clean, the grey thing on the front is at  between 1 and 2 km, the white building behind is at about 2,5 km, the television tower is at around 9 km, and the buildings on the back, I didn't even know I could see something that far.

  This is at about 1 km from home.

  Same shot, different lens aperture.

  That's not even the fastest speed of the homemade shutter, so I sure can take picture in bright daylight now.

  There's still that blurry trouble, I suspect a bounce back of the rear of the build, where the camera is mounted, when the bungee's released, the movement is very fast and stops : there are clearly 2 images, one is slightly less exposed (lighter) and another nearly well exposed (darker), it's not a blurry line.

  The rear end isn't fixed at all on anything, it just lies on a square aluminium tube mounted on a tripod.

  It's for sure easier to manipulate to aim, but it must be tightly fastened when taking a picture : easy fix.

  And, all those tests have been made with an Olympus digital camera which sensor size is 24 x times smaller than the 4 x 5 " film that feeds the film camera.

  This is from the Olympus.

  This is what the image is going to be on film.

  So I'm very optimistic about the blur. Of course the rear end must be fastened, and then I can make more tests, with B & W films loaded for the first time in more than 30 years : it's cheaper and more convenient to process, and also the lens has some optical characteristics that can be very interesting in B & W.

  I think it's some kind of requirement for a lens shooting from above, at a far distance, to have a very small dynamic range : when looking at the histogram, in the viewfinder when shooting, to have the best exposure, and in the raw developing software, it's very narrow :

  This is the unprocessed file, no risk of highlights clipping or too dark shadows.

  Same camera, cheap (but not bad) zoom lens, the histogram is much wider.

• Family picture

  [zit] Olivier Gade • 06/01/2022 at 11:24 • 0 comments

  Every part build since about 3 month, on the back from the left, the previous lens board, the Sinar board replica strapped on the below, the shutter, the lens, and in the front the Sinar bench tube adapter, another Sinar Board replica with the Nikon F baïonnette and the blade.

• Lens caps

  [zit] Olivier Gade • 06/01/2022 at 10:55 • 0 comments

  Any lens, even the biggest ones, deserve a lens cap. The two circles remaining of the shutter frame are going to be perfect.

  Milled with the 2 mm bit was very fast and easy.

  Now the beast is secured.

  Before, I had to, very, VERY carefully make the front opening round again with a nice hammer, as the lens might have felt on the floor because the brass surrounding had an impact mark and was deformed.

• Tightening the bungee

  [zit] Olivier Gade • 06/01/2022 at 10:42 • 0 comments

  As the speed was too slow to have the possibility to take pictures on a bright sunny day, the bungee needed to have more tension.

  After a too violent trial with 300 mm off, it's about 200 mm shorter now and it will give a faster speed.

  The tightening of the bungee is achieved with a Serfex clamping ring.

• Nuts

  [zit] Olivier Gade • 06/01/2022 at 09:10 • 0 comments

  A brass hexagonal 27 mm bar gives the necessary material, it had been used as a chisel or something as the end part's been completely deformed by a hammer's numerous hits.

  The center part's still red hot of the light saber cut (a reflection of the very rare sun in my workshop on a red plastic can).

  Using an équerre à centrer (centering square) to mark the place to drill the central hole.

  Makes so nice chips !

  Trying to mill, it's long, not the appropriate bit for the shape needed.

  Hand filling's faster and doesn't make noise, vibrations, and gives my arms and hands a good exercise.

  First a tough file, and a smoother, and a much smoother, and sand paper, from 400 to 2000 grain, brass is very pleasant to work with.

  It'll give a good grip.

  It needs a shoulder, in the center, the head size's perfect.

  Milling is easy.

  Not very fast but not too long.

  A little filling, to have a nice rond shape.

  And that's it : a completely home made 3/8 " screw with its tightening nut.

  The second one was faster to achieve and has a nice guilloché finish.

• Adding a cute spirit level

  [zit] Olivier Gade • 06/01/2022 at 09:00 • 0 comments

  Searching for something completely different in a small drawer, that very cute vintage and still accurate German Linhoff camera spirit level was found, I must use it !

  The price tag, 33 francs (around 5 €) and the all aluminium build let think that it's something sold in the early 70's (the orange color of Odeon photo, the shop's name, is another significant clue).

  You can see that my wood bench is quite well leveled.

  Once again, those nicely machined aluminium parts are going to be used, as it's exactly the right thickness.

  Cut with a metal hand saw and, as it's impossible to bend, the mini vice-grip will help cut the inner edge easily.

  It fits exactly.

  as the existing holes where too close to the level path, it had to be drilled again, not very elegant, but... it's a prototype.

  Drilling, taping, just in the center, between the ears.

  Parfait ! ugly, but nobody will ever notice it.

• Spring time again

  [zit] Olivier Gade • 06/01/2022 at 07:36 • 0 comments

  Some more 35 mm film canisters are easily cut : the blade needs more bumpers at the end of the movement.

  Easy to shape.

  In the small vise, you can see how mat is the inner black paint on this picture.

  A forest of springs !

  Finally, two of them are going to be taken away, as they where touching the back of the blade, the breaking is enough with 6 springs (the blade finishes it's run by a smooth 4 centimeter upwards movement) .

• Reinforcing the build

  [zit] Olivier Gade • 05/31/2022 at 17:39 • 0 comments

  Another of these 5 mm thick aluminium L is going to be used, cut in two halves.

  The 2 mm square tube is too weak. That'll be stronger.

  Drilling, taping, as you can see, stainless steel screws are used.

  It's nice to have a big jaws vise on the bench.

  M3 screws in an 5 mm thick plate, it'll do, but it was close to the disaster.

  As the L shape are bigger than the 30 mm square tube, the alignement with the rear part of the build is perfect and easy now.

• Second try, is the shutter fast enough ?

  [zit] Olivier Gade • 05/31/2022 at 17:28 • 0 comments

  That television tower is at about 10 kilometers from home, the blur is mostly due to the air pollution.

  This has been taken with the shutter of my Olympus camera.

  This is with the shutter I made, it's much more blurry and at the fastest speed, not fast enough.

  Let's try a closer easier to focus frame.

  From the TV tower to the (much closer) TV antennas. (Olympus shutter 1/125 s.)

  Nearly the same exposure value with my shutter, but... ok, the wind was very strong, but... something must be made to strengthen the system.

  And the bungee string must be tightened to have a faster speed.

• Coin-coin (two wedges)

  [zit] Olivier Gade • 05/31/2022 at 17:04 • 0 comments

  After a release, it slipped nearly 5 mm.

  The blind is slipping, even with the screw completely tighten, the shock of the shutter release mechanism is too strong, so some wedges are necessary.

  This very soft aluminium recuit (annealed) is really easy to bend.

  But adjustment is not simple at all, and it's absolutely necessary that the shutter speed change do not affect the framing of the picture, it must be easy to do and fast.

  A pair of coins (wedges) are made with the help of the vise with that mellow aluminium, the sharp end is thinner than half of the thickness of the material.

  After a try, no move, the design is validated.

  Some more of the nice sintered parts are used to have a good grip : it's wedges, so it's hard to put in place, and its good to have a lever to take it off.

  The first uses of the screw had the skin of my finger tips completely worn : some rounding, softening is necessary. Rond File.

  Sanding.

  A moment in the M 6 die to have perfect entrance.

  I don't want to loose those wedges, after unsuccessful search for some very small bungee strings, I finally chose to make a string out of that enameled steel wire, it's very strong (hard to brake) and very soft (easy to bend).

  Tresser, c'est facile ! (weaving is easy !), Never done that before, but it's a gesture that's been done so many times by our ancestors, that I feel my body remembers their actions.

  I didn't need so much of that stuff... next time, another use.

View all 56 project logs