Tuesday, June 28, 2016

First "Real" Lathe Project - Argus Cintagon II 48mm f2

My buddy Cliff got me some aluminium rounds and now I can actually do some "real" lathe project :)

The aluminium rounds came in 12-inch lengths.  I really should have them cut into 2 inch pieces, because cutting a 2.5" diameter round took almost 20 minutes with a hack saw by hand.  I originally thought that I would cut each piece to the lengths I want, so I won't waste any materials as they are quite expensive, but that does not seem like a great idea now.  In any case, the very first lens I want to make usable on my A7 is the Argus Cintagon 48mm f2 lens that came from a Argus rangefinder.

The reason I choose this lens is because it's the easiest one to do.  All it needs is a proper length of tube between a mount and the lens.  I thought it would be a piece of cake.  I just needed to bore out the piece, drill and tap the screw holes and it's done.  What could be simpler?

The pieces - Left: thin mount, middle: tube I worked on, left: the lens 

Well, it's not really hard, but it has taken far longer than I thought.  As my first time turning and facing a piece of solid metal, there were (and still are) lots of things to learn.  What tool bits to use, truing the work piece, etc.  While boring out the required space to fit the lens, the weakness of a micro lathe is quite apparent.  There is simply not much power/torque for deep cuts/turns.  Everything must be done slowly, even on soft metal like aluminium.

I am happy to say, the piece is is almost done, except I need to drill, and tap the screw holes for the tube on the side, and the mount at the back, and there is only one problem.  I don't have any small tap tools, drill bits, and a drill stand.  This whole business of lens conversion takes so many other tools and accessories that I didn't think of at first.  In any case, I ordered a Flexshaft for my Dremel 4000 from Amazon, and it came in a couple of days.  I am going to mount it on the cross-slide, somehow, and drill the holes on the side with the tube/lens mounted on the lathe chuck.  For the mount, the holes need to be drilled on the back, I think I will mount the Flexshaft on the tail-stock and hold the mount/tube with the chuck.  For all this to work, I have to make a mounting jig for the Flexshaft and secure it on the cross-slide and tail-stock.

All fitted together.  Still need to be screwed together.

It's almost impossible to buy a set of micro tap and tiny screws locally at reasonable prices, if you could find them at all.  I order a thousand pieces of M2 (two millimeter x 5mm) screws, a set of small drill bits and a set of 10 micro taps with size from M1 to M3.5, with handle for about $40 from AliExpress. The only problem is, shipping usually takes at least a month, and on top of that, Canada Post is likely going on strike next week and who know for how long.  In the mean time, I have an urge just glue this thing together until all the parts arrive :)

It's very gratifying to see all the pieces fit together and I am very glad I bought the lathe.  I think I am going to enjoy this.

Argus Cintagon II 48mm f2 Sample

Thursday, June 16, 2016

Benoist Berthiot 100mm f2.2 Cinestar N2 Projection Lens

When I saw a beautiful portrait taken by Jérôme B. on Flickr with the Benoist Berthiot 150mm f3.3 cine lens, I was intrigued.  I have always loved French lens.  When I got a bunch of projection lenses from the camera show last time, and it included not one, but two French lenses, I was really happy.  One of the lenses was a Benoist Berthiot 100mm f2.2 Cinestar N2.

Benoist Berthiot 100mm f2.2 Cinestar N2.  My second lens project with the lathe, which turned out much better than the last one.

I assume that this lens was probably derived from a cine lens, since it has a name like Cinestar.  The lens covers full frame, even at infinity.  But the lens was really made for 16mm projectors, so even when there is no vignetting, the edges are mushy.  But this is not a landscape lens, edge sharpness is not important at all.  For the kind of pictures that are normally taken with a lens like this, rendering character is far more a consideration.

I put this lens on the lathe last night and turned it enough just to remove the grooves on the lens, and slip on a 37-52mm step-up ring, and it goes on a modified Vivitar 2X macro teleconverted helicoid.  The lathe job is much much better than my last attempt.  I used a 4-jaw chuck, and with the aid of a dial indicator, I was able to get the lens to turn pretty round, hence the much smoother finish.

Sitting at the dock of the lake - Benoist Berthiot 100mm f2.2 Cinestar N2 & Sony A7.

The lens hood I used was slightly too long, and it created some vignette at longer focus distance.  That's completely OK by me.  As expected, the center sharpness is very impressive.  The rendering style is very much like the 150mm f3.3 lens Jérôme B used, so maybe they share similar optical designs.

This lens can create some interesting portraits, like the 150mm version does. I think I will explore more with this interesting gem.

Swirly Bokeh - Benoist Berthiot 100mm f2.2 Cinestar N2 & Sony A7

Man & his best friend - Benoist Berthiot 100mm f2.2 Cinestar N2 & Sony A7

Wednesday, June 8, 2016

First Lathe Lesson - Centering the Work Piece

I want to share my experience with anyone who is considering or starting to play with a metal lathe, and will post whatever I consider useful.

I wrote last time about the very bad run out of the 3-Jaw chuck.  Did some more research and found that there isn't too much can be done about the chuck itself, other than buying a high quality one with high precision.  But that is just one of the factors that affect the precise centering of the work piece.  A 4-Jaw chuck is still a little better, but it takes much longer to get everything true.  I have a dial gauge with a magnetic base on order and should be here soon.  In the mean time, I learned that using a ball bearing can make the work piece on a 3-Jaw chuck run much more true than without.

Got a broken bicycle bottom bracket that has a ball bearing still on, and it broke at the perfect place.  I really don't need to modify it, except to thread a screw on it, and then clamp it on a tool post, like this:

Work piece centering tool using a ball bearing from a broken bicycle bottom bracket.

To use it, mount the work piece just tight enough that it won't come off when the lathe is turned on.  Run the lathe in slow speed, and gradually a advance the ball bearing until the bearing start to turn.  The work piece should now run true enough to start turning.  I don't have the dial gauge yet to check the run out, but to my eye, it was light years better than when I was turning the Angenieux 70mm f1.5 projection lens.

All these changing of tool posts and change the belt position for different speed of the lathe is quite tedious.  All the more motivation to convert this lathe to use a variable speed DC motor, and buy a quick change tool post.

Water Quality Sampler Post - Zeiss Opton Tessar 75mm f3.5 & Sony A7

Monday, June 6, 2016

My First [Simple] Lathe Project

Yesterday I finally found some space to setup the lathe.  Unfortunately I have no metal rounds to practice with, so I used a projection lens I bought from the camera show couple weeks ago as the practice piece and first project.  Yes, I know.  I am trying to walk before I learn how to crawl, but hey, I have many hours of YouTube experience under my belt.  That's got to be good enough to get started, right?

Immediately, I found many problems. The carriage had quite a bit of play.  A quick consultation with the Taig Micro Lathe guide fixed it by adjusting the gib screws. Then the 3-Jaw chuck is grossly out of true.  It's so bad you can see the wobble and it would be impossible to turn anything like this until I find a way to true it. The 3-Jaw chuck is supposed to be self centring, as all the jaws move at the same time when you tighten/loosen it, but it's not doing a good job at it. Luckily, there is the 4-Jaw chuck that was included with the lathe, but that brought up another problem.  The 4-Jaw chuck's jaws are independent.  You can tighten each of the 4 jaws individually.  But, in order to make the work piece perfectly centred, one needs a dial gauge, which I have, but I don't have the base to set it.  So in the end, I just did many trial and error tightening and retightening until it was visually running true. This is a laborious and imprecise process without the dial gauge.

Finished - I will not show you the 100% crop of the turned area.  It just looks disgusting.

I removed the lens elements from the lens; they came off easily by unscrewing the front and rear groups.  This is part of the reason I wanted to use this lens.  The lens barrel was then mounted on the 4-Jaw chuck with as true as I could visually tell, and started turning.  I just wanted to remove the grooves on the lens so that it would have a smooth surface, and it would also provide a stop for the step-up ring that I would use to mount it to the focus helicoid.  This turned out really bad ugly.  For one thing, the tool bits were all dull, and I think the speed I was using was a bit too slow.  I am not sure what kind of metal the lens barrel was made of, but it was not aluminium or brass. In the end, I removed the large, smooth grooves on the lens, but left behind tiny and sharp grooves.  It looks nothing like the smooth finish I see on YouTube!

Angenieux 70mm f1.5 Projection Lens on the helicoid

Next I wanted to bore the hole larger on the 30-52mm step-up ring, just large enough to slip on the lens barrel.  This part was done relatively painlessly.  The aluminium of the step-up ring was much easier to work with.

So, in a way, it was a success, only because I was able to use the lens and I didn't have to go nuts trying to find a ring that fits the lens barrel and trying to glue it so that it's parallel to the mount.

What did I learn from the first lesson in using a metal lathe?  It's kind of fun, but what overwhelmed me was the sheer amount of metal shavings from such a small and simple project.  A Shopvac is a must.  To make the lathe run smoothly and efficiently, it needs to be optimally conditioned: true chucks, sharp bits, right kind of bits, right accessories and most of all, the skills to make it sing.  I will keep doing simple projects until I am comfortable to convert a real lens.

Daisies - Angenieux 70mm f1.5 Projection Lens & Sony A7

Friday, June 3, 2016

Making Your Own Photobooks

To me, nothing beats a physical photo book that you can hold in your hands and flip through to enjoy.  There is a sense of timelessness to browsing and reading a physical book.  It's even more gratifying to hold a book that's made by you.

In the past, if you want to print a book, you would have to find a publisher, and print in large quantities.  But now, print on demand is extremely accessible to everyone.  You can print one book, if you wish, or a thousand if you want to sell it, and there are many companies now offering this book printing service.  I will talk about two that I have used: Blurb and Photobook Canada (or Photobook America/Worldwide).

Blurb -- This is the first book printing company I used.  I printed a total of three books, but none for myself.  Two wedding books for my sister-in-law, and a soft cover book for a friend.  It has been at least 6 or 7 years since I used them last time, so my past experience might not match how they operate now.

What I like best:

  • Print quality.  In my opinion, it's slightly better than Photobook Canada, but it's a close call.
  • Sophisticated book making software (free)
  • Generally lower price than others (until I discovered Photobook Canada)
  • Fast turn around
  • A lot of paper upgrade options, but it also quickly makes the book expensive.
  • If you want to sell your book Blurb has connections selling to both Amazon and Apple iTune/iBook store.

What I don't like much:

  • Book making software is not as easy to use as others (this could be different now, though)
  • Promotions (they often have 25% to %40 off specials) only lasts a few days and if you don't already have a book created and ready, you will miss it. 
  • Higher cost (compared to Photobook Canada)
  • Smaller book sizes.  Instead of 11" x 8.5", Blurb offers 10x8 inch.  I like the slightly larger size and the aspect ratio of the standard 11x8.5 inch paper.
  • Default paper is not as nice as that used by Photobook Canada

When I started using Blurb, the default page count of an 10x8 inch book was 40 pages and cost less than $40, which was excellent price.  But now I just checked their web site and the default page count is 20, like pretty every other book publishers and it costs around $37CAD.  So the price has gone up significantly and is no longer the most affordable printer.

Photobook Canada [or Photobook America or Photobook Worldwide] -- This is the service I use right now.  I have printed 8 books so far from 11" x 8.5" to 17.5" x 12".  Generally, I like the image quality, but don't expect commercial photobook grade.  The books are printed in Malaysia and shipped to Toronto (for me) by DHL.

What I like

  •  Excellent default paper.  Paper upgrade is available, although not as extensive as what Blurb offers, but I find the default Premium Silk paper to be excellent, especially on the 17.5" x 12" inch size.
  • The best price of any book printer I have found, if you wait for the promotion (pretty much weekly).  Often you can buy 8.5"x11" hardcover books for $20 to $25 CAD, including taxes but shipping is usually extra.  Occasionally, they offer free shipping with some promotions. I purchased three 40 page 14" x 11" size books at $25 CAD each, including taxes, plus $13 shipping by DHL for each book, and a 17.5" x 12" 40 page book for $45CAD, just want to see what my pictures look like in a large format book.  That's crazy good price for large format hard cover books.  Best of all, with the promotion, you can purchase the book voucher, and do your book later.  The voucher is good for 3 to 6 months, depending on how many vouchers you buy or number of pages of the book you purchase at the time.  This also forces you to actually create the book or you will lose the vouchers.  In contrary, when Blurb has a promotion, it's usually only good for a few days.  If you don't have a book already to print, too bad, unless you can create a book in 3 days.
  • Print quality is very acceptable.  At first you may be disappointed that the pictures printed does not look as vibrant or has the same shadow details as the picture on your monitor, but you have to remember that paper/ink does not have as wide a colour gamut as your monitor.
  • The software can generate a low quality proof of the book that you can share with friends and family, without watermarks.
  • Extremely fast turn around.  I almost always get the book within 5 business days after uploading to their server.  DHL usually delivers the book within 3 business days while the printing takes a day or two.  I was originally a bit unhappy about the high delivery cost, as Blurb cost around $8 when I did books with them (it could be more, or less than that now, I am not sure) but I have realized the book comes from Malaysia and it ends up in my hands in Toronto in a few days is quite amazing.

What I don't Like

  •  I would like the print quality to be a bit better.  I think the compression is a bit too much when they assemble the book for upload.  This is the same for Blurb.  For Blurb, an 80 page, 10" x 8" inch book came out to be less than 90MB.  Photobook Canada does not leave the finished book behind once it's uploaded to the server, so I don't know exactly how large the file is.
  • Relatively high delivery cost.  Would be nice to have a lower cost option for slower delivery.
  • Book making software not very sophisticated.  The most annoying aspect of the software is that it pauses every 10 to 15 minutes to do some housekeeping tasks and that freezes the app until it's done.  Saving also takes a long time.  I like Blurb's software, that it automatically and continuously saves all the changes.   

In the end, it does not matter which service you use.  Having your own book in your hands is a great feeling of accomplishment.  Books are better archival mediums than hard drives and optical discs, and you can pass them around for others to enjoy.  So far I have made one book for each of my kids (and there will be at least a few more for each), and I am sure they will like it when they grow older and see the pictures of themselves and they may even pass the books to their kids.

Size comparison: Top - 11" x 8.5", middle - 14" x 11", bottom: 17.5" x 12"